@article{cooper-khan_frankovich_thompson_thomovsky_lewis_2024, title={Clinical Findings and Outcome in 30 Dogs with Presumptive or Confirmed Nerve Sheath Tumors}, volume={11}, ISSN={2306-7381}, url={http://dx.doi.org/10.3390/vetsci11050192}, DOI={10.3390/vetsci11050192}, abstractNote={Nerve sheath tumors (NSTs) are well-recognized primary nervous system tumors, but there is relatively limited information in dogs including comparison of NSTs in different anatomical locations. This retrospective study describes the clinical features and outcomes in a group of dogs with NSTs affecting the cranial nerves or spinal nerves. Thirty dogs were included, 25 with a presumptive diagnosis and five confirmed by histopathologic analysis. Seven dogs also had cytology of tumor samples, which were supportive of the NST diagnosis in four. Eight dogs had cranial nerve-associated NSTs, with six involving the trigeminal nerve. Twenty-two dogs had spinal nerve-associated NSTs including 13 invading the spinal canal and nine peripheral to the spinal canal, with the majority affecting nerves or nerve roots of the brachial plexus. The prognosis was poor, with dogs being euthanized eventually because of disease progression. Among dogs alive 1 week after diagnosis, the median survival time was 4 months but ranged from 2 weeks to >2 years. While there was a broad overlap between NST locations, survival was generally longer for dogs without spinal canal or intracranial involvement. The results expand available information on NSTs in dogs but should be interpreted with caution given the small number of dogs with a definitive diagnosis. Further investigation is warranted to determine how tumor location, invasiveness, and treatments pursued impact outcome.}, number={5}, journal={Veterinary Sciences}, publisher={MDPI AG}, author={Cooper-Khan, Rachel S. and Frankovich, Alexandra N. and Thompson, Craig A. and Thomovsky, Stephanie A. and Lewis, Melissa J.}, year={2024}, month={Apr}, pages={192} } @article{lewis_2024, title={Electrodiagnostic testing in dogs with disorders of the spinal cord or cauda equina}, volume={304}, ISSN={1090-0233}, url={http://dx.doi.org/10.1016/j.tvjl.2024.106082}, DOI={10.1016/j.tvjl.2024.106082}, abstractNote={Electrodiagnostic (EDX) testing is uncommonly utilized in dogs other than for investigation of disorders of the neuromuscular system. In dogs with diseases affecting the spinal cord or cauda equina, EDX testing can provide functional data complementary to imaging information that together can guide therapeutic and management approaches. Additionally, in some clinical scenarios, EDX testing prior to advanced imaging is integral to identifying if there is spinal cord or cauda equina involvement and can aid in determining the appropriate diagnostic path. This review will outline EDX testing methods that have been reported in dogs relating to the diagnosis, monitoring or prognosis of various conditions affecting the spinal cord and cauda equina. The various tests will be briefly outlined regarding how they are performed and what information is provided. The main focus will be on clinical applications including highlighting situations where EDX testing is useful for differentiating between neurologic and non-neurologic presentations. Additional ways these EDX techniques could be incorporated in the management of diseases of the spinal cord and cauda equina in dogs will be presented.}, journal={The Veterinary Journal}, publisher={Elsevier BV}, author={Lewis, M.J.}, year={2024}, month={Apr}, pages={106082} } @article{togawa_lewis_devathasan_2024, title={Outcome in paraplegic dogs with or without pain perception due to thoracolumbar fibrocartilaginous embolic myelopathy or acute non-compressive nucleus pulposus extrusion}, volume={11}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2024.1406843}, DOI={10.3389/fvets.2024.1406843}, abstractNote={Fibrocartilaginous embolic myelopathy (FCEM) and acute non-compressive nucleus pulposus extrusion (ANNPE) are common causes of acute spinal cord injury in dogs. Outcome among paraplegic deep pain positive (DPP) and deep pain negative (DPN) dogs with either condition and factors influencing recovery have not been clearly established.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={Togawa, Go and Lewis, Melissa J. and Devathasan, Dillon}, year={2024}, month={May} } @article{lewis_early_bergman_love_nelson_2024, title={Quantification of metallic artifact on CT associated with titanium pedicle screws}, volume={11}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2024.1448188}, DOI={10.3389/fvets.2024.1448188}, abstractNote={In dogs undergoing vertebral column stabilization, post-operative computed tomography (CT) evaluates implant placement. The impact on the interpretation of metallic artifact associated with titanium implants in dogs remains to be established. Our objective was to quantify metallic artifact on CT associated with titanium pedicle screws.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={Lewis, M. J. and Early, P. J. and Bergman, R. and Love, K. and Nelson, N.}, year={2024}, month={Jul} } @article{ostrager_bentley_lewis_moore_2024, title={Survival in dogs with meningoencephalomyelitis of unknown etiology with and without lesions detected by magnetic resonance imaging}, volume={38}, ISSN={0891-6640 1939-1676}, url={http://dx.doi.org/10.1111/jvim.17109}, DOI={10.1111/jvim.17109}, abstractNote={Abstract Background The prognosis of individual dogs with meningoencephalomyelitis of unknown etiology (MUE) remains difficult to predict. MUE cases with no lesions detected by magnetic resonance imaging (MRI) occur, but it is unknown whether this finding is associated with prognosis. Hypothesis MUE cases without detectable lesions on MRI have a better outcome than cases with detectable lesions. Animals Study included 73 client‐owned dogs with MUE presenting to Purdue University Veterinary Hospital from 2010 to 2020. Methods Retrospective study. Dogs with a clinical diagnosis of MUE were identified by medical record search. MRI reports were reviewed for presence or absence of lesions consistent with MUE. Clinical findings at presentation, treatment, disease‐specific survival, and outcomes including rates of remission and relapse were compared between cases with normal MRI or abnormal MRI. Results Overall, 54 dogs (74%) were classified as abnormal MRI, and 19 dogs (26%) were classified as normal MRI cases. Death caused by MUE occurred in 1/19 (5%) normal MRI dogs and 18/54 (33%) abnormal MRI dogs ( P = .016). Median survival was >107 months in both groups, but survival was significantly longer in the normal MRI group ( P = .019). On multivariate analysis, abnormal MRI was significantly related to death (hazard ratio, 7.71; 95% confidence interval 1.03‐58.00, P = .0470), whereas significant relationships with death were not identified for either the use of secondary immunosuppressive medications or cerebrospinal fluid nucleated cell count. Conclusions MUE dogs with no detectable lesions on MRI have reduced disease‐related death compared with dogs with abnormal MRI. The presence or absence of MRI lesions in MUE dogs is prognostically relevant.}, number={4}, journal={Journal of Veterinary Internal Medicine}, publisher={Wiley}, author={Ostrager, Arielle and Bentley, R. Timothy and Lewis, Melissa J. and Moore, George E.}, year={2024}, month={May}, pages={2204–2213} } @article{linder_mehra_miller_lewis_bentley_thomovsky_2024, title={Use of levetiracetam for the successful treatment of suspected myoclonic seizures: five dogs (2016‐2022)}, volume={65}, ISSN={0022-4510 1748-5827}, url={http://dx.doi.org/10.1111/jsap.13719}, DOI={10.1111/jsap.13719}, abstractNote={Myoclonic seizures are considered a type of generalised seizure characterised by brief, jerking movements of the body. The aim of this study is to describe cases of suspected canine myoclonic seizure of idiopathic aetiology and to discuss the successful use of the anticonvulsant levetiracetam as treatment in each of these cases.}, number={6}, journal={Journal of Small Animal Practice}, publisher={Wiley}, author={Linder, J. and Mehra, J. and Miller, S. and Lewis, M. J. and Bentley, R. T. and Thomovsky, S.}, year={2024}, month={Apr}, pages={402–408} } @article{lewis_thomovsky_moore_2023, title={Adaptation of land treadmill scoring system for underwater treadmill in dogs with thoracolumbar intervertebral disc extrusion}, volume={300-302}, ISSN={1090-0233}, url={http://dx.doi.org/10.1016/j.tvjl.2023.106039}, DOI={10.1016/j.tvjl.2023.106039}, abstractNote={The underwater treadmill (UWTM) is utilized in dogs recovering from thoracolumbar intervertebral disc extrusion (TL-IVDE). Gait scoring is validated for dogs with TL-IVDE walking on the land treadmill (LT) but has not been reported for the UWTM. Our objective was to investigate if LT gait analysis could be applied to the UWTM and if non-ambulatory dogs walking unassisted on the UWTM, at a standardized water level, would be more likely to generate gait scores compared to on the LT. This was a prospective, observational study in dogs with TL-IVDE managed surigcally. At 0, 2, 4, 8 and 12 weeks post-operatively, paired video footage of dogs walking on the LT and UWTM (water level at the greater trochanter) was used to generate 0-100 stepping (SS) and coordination (regularity index, RI) scores. Scores were compared between treadmill type and over time. Twenty dogs were enrolled and seventy-eight paired recordings were available for review. Median gait scores increased over time but did not differ by treadmill type (P = 0.262 for SS, P = 0.533 for RI). Combining SS and RI, more recordings received scores of 0 for the LT (n=58/156; 37.2%) compared to the UWTM (n=44/156; 28.2%; P = 0.043). Scores of 0, at visits when there was at least movement present at multiple joints, was more common on the LT (n=11/108; 10.2%) compared to the UWTM (n=2/108, 1.9%; P = 0.026). In dogs recovering from TL-IVDE, LT-based gait scoring was feasible in dogs walking on the UWTM and might complement other gait analysis methods, especially for non-ambulatory dogs.}, journal={The Veterinary Journal}, publisher={Elsevier BV}, author={Lewis, M.J. and Thomovsky, S.A. and Moore, G.E.}, year={2023}, month={Oct}, pages={106039} } @article{mehra_tolbert_guadiano_steiner_moore_lewis_2023, title={Double‐blinded placebo‐controlled clinical trial of prophylactic omeprazole in dogs treated surgically for acute thoracolumbar intervertebral disc extrusion}, volume={37}, ISSN={0891-6640 1939-1676}, url={http://dx.doi.org/10.1111/jvim.16642}, DOI={10.1111/jvim.16642}, abstractNote={Abstract Background Proton pump inhibitors are administered prophylactically in dogs treated surgically for acute thoracolumbar intervertebral disc extrusion (TL‐IVDE). However, their efficacy in decreasing gastrointestinal (GI) complications is unknown. Hypothesis Omeprazole does not decrease the frequency of GI complications compared to placebo in dogs treated surgically for acute TL‐IVDE. Animals Thirty‐seven client‐owned dogs undergoing hemilaminectomy for acute TL‐IVDE. Methods Randomized double‐blinded placebo‐controlled prospective clinical trial. Dogs received PO placebo or omeprazole at 1 mg/kg q12h for 5 days during hospitalization. Development of GI signs (e.g., diarrhea, vomiting, regurgitation, hematochezia, melena) was recorded daily. Clinicopathologic testing performed during hospitalization and at 2 and 4‐week re‐evaluations included: fecal occult blood, PCV, blood urea nitrogen/creatinine ratio, fecal calprotectin, canine pancreatic lipase immunoreactivity and fecal alpha‐1 proteinase inhibitor concentrations. Omeprazole and placebo groups were compared using chi‐squared or Fisher's exact tests. Results Gastrointestinal signs developed in 10/20 (50%) dogs in the omeprazole group and in 7/17 (41%) dogs in the placebo group ( P = .59). Diarrhea was common (8/20 omeprazole, 5/17 placebo), hematochezia was rare (1/20 omeprazole, 1/17 placebo); melena was not observed. Clinicopathologic evidence suggestive of bleeding was present in 9/20 dogs treated with omeprazole and in 11/17 dogs that received placebo ( P = .23). Fecal occult blood positivity was more common in dogs with GI signs ( P = .03). Canine pancreatic lipase immunoreactivity was higher during hospitalization compared to re‐evaluations ( P = .01). Conclusions and Clinical Importance Short‐term, prophylactic omeprazole treatment did not decrease clinically detectable GI complications in dogs with acute TL‐IVDE.}, number={2}, journal={Journal of Veterinary Internal Medicine}, publisher={Wiley}, author={Mehra, Jaya M. and Tolbert, M. Katherine and Guadiano, Phillip and Steiner, Jörg M. and Moore, George E. and Lewis, Melissa J.}, year={2023}, month={Feb}, pages={586–597} } @article{olby_olby_moore_brisson_fenn_flegel_kortz_lewis_tipold_2022, title={ACVIM consensus statement on diagnosis and management of acute canine thoracolumbar intervertebral disc extrusion}, volume={36}, ISSN={0891-6640 1939-1676}, url={http://dx.doi.org/10.1111/jvim.16480}, DOI={10.1111/jvim.16480}, abstractNote={AbstractBackgroundThoracolumbar intervertebral disc extrusion (TL‐IVDE) is the most common cause of acute paraparesis and paraplegia in dogs; however, guidelines on management of the condition are lacking.ObjectivesTo summarize the current literature as it relates to diagnosis and management of acute TL‐IVDE in dogs, and to formulate clinically relevant evidence‐based recommendations.AnimalsNone.MethodsA panel of 8 experts was convened to assess and summarize evidence from the peer‐reviewed literature in order to develop consensus clinical recommendations. Level of evidence available to support each recommendation was assessed and reported.ResultsThe majority of available literature described observational studies. Most recommendations made by the panel were supported by a low or moderate level of evidence, and several areas of high need for further study were identified. These include better understanding of the ideal timing for surgical decompression, expected surgical vs medical outcomes for more mildly affected dogs, impact of durotomy on locomotor outcome and development of progressive myelomalacia, and refining of postoperative care, and genetic and preventative care studies.Conclusions and Clinical ImportanceFuture efforts should build on current recommendations by conducting prospective studies and randomized controlled trials, where possible, to address identified gaps in knowledge and to develop cost effectiveness and number needed to treat studies supporting various aspects of diagnosis and treatment of TL‐IVDE.}, number={5}, journal={Journal of Veterinary Internal Medicine}, publisher={Wiley}, author={Olby, NJ and Olby, Natasha and Moore, Sarah and Brisson, Brigitte and Fenn, Joe and Flegel, Thomas and Kortz, G and Lewis, Melissa J and Tipold, Andrea}, year={2022}, month={Jul}, pages={1570–1596} } @article{olby_moore_brisson_fenn_flegel_kortz_lewis_tipold_2022, title={ACVIMconsensus statement on diagnosis and management of acute canine thoracolumbar intervertebral disc extrusion}, volume={36}, ISSN={0891-6640 1939-1676}, url={http://dx.doi.org/10.1111/jvim.16480}, DOI={https://doi.org/10.1111/jvim.16480}, abstractNote={Abstract Background Thoracolumbar intervertebral disc extrusion (TL‐IVDE) is the most common cause of acute paraparesis and paraplegia in dogs; however, guidelines on management of the condition are lacking. Objectives To summarize the current literature as it relates to diagnosis and management of acute TL‐IVDE in dogs, and to formulate clinically relevant evidence‐based recommendations. Animals None. Methods A panel of 8 experts was convened to assess and summarize evidence from the peer‐reviewed literature in order to develop consensus clinical recommendations. Level of evidence available to support each recommendation was assessed and reported. Results The majority of available literature described observational studies. Most recommendations made by the panel were supported by a low or moderate level of evidence, and several areas of high need for further study were identified. These include better understanding of the ideal timing for surgical decompression, expected surgical vs medical outcomes for more mildly affected dogs, impact of durotomy on locomotor outcome and development of progressive myelomalacia, and refining of postoperative care, and genetic and preventative care studies. Conclusions and Clinical Importance Future efforts should build on current recommendations by conducting prospective studies and randomized controlled trials, where possible, to address identified gaps in knowledge and to develop cost effectiveness and number needed to treat studies supporting various aspects of diagnosis and treatment of TL‐IVDE.}, number={5}, journal={Journal of Veterinary Internal Medicine}, publisher={Wiley}, author={Olby, Natasha J. and Moore, Sarah A. and Brisson, Brigitte and Fenn, Joe and Flegel, Thomas and Kortz, Gregg and Lewis, Melissa and Tipold, Andrea}, year={2022}, month={Jul}, pages={1570–1596} } @article{devathasan_murakami_miller_thomovsky_lewis_2022, title={Case Report: Recurrence of an Extradural Spinal Epidermoid Cyst Following Surgical Excision in a Dog}, volume={9}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2022.871023}, DOI={10.3389/fvets.2022.871023}, abstractNote={Congenital epidermoid cysts are slow-growing, mass lesions caused by the abnormal inclusion of neuroectodermal tissue within the developing central nervous system. Subtotal excision of epidermoid cysts increases the risk of early recurrence of clinical signs. A 4-year-old female spayed boxer was presented with a 4-month history of ambulatory paraparesis and proprioceptive ataxia. Neurological examination localized a T3-L3 myelopathy. MRI revealed a T1 iso- to hypointense, T2 and FLAIR hyperintense, rim-enhancing mass at the level of the T9-T10 vertebrae resulting in extradural compression of the spinal cord. This was histopathologically confirmed as an extradural epidermoid cyst following subtotal excision. MRI performed 2 months post-operatively revealed a significant decrease of the lesion volume. The dog was neurologically normal following the surgery however re-presented 28 months later with recurrence of clinical signs. A 28-month post-operative MRI revealed substantial enlargement of the epidermoid cyst. The dog was subsequently taken for repeat decompressive surgery. At 6 months from the repeat surgery, the dog was neurologically static with mild proprioceptive deficits. The case report highlights the clinical and MRI features of a recurrent extradural spinal epidermoid cyst treated by subtotal excision.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={Devathasan, Dillon and Murakami, Masahiro and Miller, Margaret A. and Thomovsky, Stephanie A. and Lewis, Melissa J.}, year={2022}, month={Apr} } @article{lewis_bowditch_laflen_perry_yoquelet_thomovsky_2022, title={Pilot Study on Feasibility of Sensory-Enhanced Rehabilitation in Canine Spinal Cord Injury}, volume={9}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2022.921471}, DOI={10.3389/fvets.2022.921471}, abstractNote={Physical rehabilitation is frequently recommended in dogs recovering from acute thoracolumbar intervertebral disc extrusion (TL-IVDE), but protocols vary widely. The objective of this study was to evaluate the feasibility of incorporating sensory-integrated neurorehabilitation strategies into a post-operative rehabilitation protocol in dogs with TL-IVDE. Non-ambulatory dogs with acute TL-IVDE managed surgically were prospectively recruited to this unblinded cross-over feasibility study. Eligible dogs were randomized to start with tactile-enhanced (artificial grass) or auditory-enhanced (floor piano) basic rehabilitation exercises performed twice daily for the first 4 weeks before switching to the opposite surface for the subsequent 4 weeks. Neurologic examination, open field gait scoring, girth measurements and an owner-completed feasibility questionnaire were performed at baseline and 2, 4, 6, and 8 weeks post-operatively. Twenty-four dogs were enrolled, 12 randomized to each order of exercises. Gait scores did not differ between the two groups at baseline, 4 or 8 week visits. All modified exercises could be performed and compliance was high. Adverse events potentially attributable to the study surface were mild, self-limiting and occurred in 2/24 dogs. The most common surface-related limitations were that the piano was slippery and that both surfaces were too short. The artificial grass was preferred by owners and dogs compared to the floor piano surface, but this was influenced by which surface was utilized first. Auditory and tactile modifications were feasible and safe to incorporate into a standardized rehabilitation protocol. This pilot study could prompt larger efficacy studies investigating the benefit of sensory-integrated rehabilitation in dogs with TL-IVDE.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={Lewis, Melissa J. and Bowditch, Jessica and Laflen, Brittany and Perry, Nicole and Yoquelet, Rachel and Thomovsky, Stephanie A.}, year={2022}, month={Jun} } @article{amaral marrero_thomovsky_linder_bowditch_lind_kazmierczak_moore_lewis_2022, title={Static Body Weight Distribution and Girth Measurements Over Time in Dogs After Acute Thoracolumbar Intervertebral Disc Extrusion}, volume={9}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2022.877402}, DOI={10.3389/fvets.2022.877402}, abstractNote={Dogs with thoracolumbar intervertebral disc extrusion (TL-IVDE) can exhibit variable neurologic deficits after decompressive surgery. The objectives of this study were to quantify changes in static weight distribution (SWD) and limb and body circumference over time in dogs recovering from surgery for TL-IVDE. Dogs with acute TL-IVDE were prospectively evaluated at baseline (48-72 h post-operatively), 2, 4, 8, and 12 weeks post-operatively. Commercially-available digital scales were used to measure weight distributed to the pelvic limbs (PL%) and asymmetry between left and right pelvic limbs (LRA), each expressed as a percentage of total body weight. Trunk and thigh circumference measurements were performed using a spring-loaded tape measurement device. Measurements were performed in triplicate, compared to neurologically normal small breed control dogs and analyzed for changes over time. P <0.05 was significant. Twenty-one dogs were enrolled; 18 regained ambulation and 3 did not by study completion. PL% increased from 27.6% at baseline to 30.7% at 12 weeks but remained lower than in control dogs (37%) at all time points (p < 0.0001), even excluding dogs still non-ambulatory at 12 weeks (p < 0.025). LRA was similar to the control dogs, and did not have an association with surgical side. Caudal trunk girth decreased over time to 95% of baseline (p = 0.0002), but this was no longer significant after accounting for reductions in body weight (p = 0.30). Forward shifting of body weight persisted in dogs with TL-IVDE 12 weeks after surgery even among ambulatory dogs. SWD and circumference measurements could provide additional objective measures to monitor recovery.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={Amaral Marrero, Natalia P. and Thomovsky, Stephanie A. and Linder, Jessica E. and Bowditch, Jessica and Lind, Mallory and Kazmierczak, Kristine A. and Moore, George E. and Lewis, Melissa J.}, year={2022}, month={Apr} } @article{lewis_shomper_williamson_vansteenkiste_bibi_lim_kowal_coates_2021, title={Brain diffusion tensor imaging in dogs with degenerative myelopathy}, volume={35}, ISSN={0891-6640 1939-1676}, url={http://dx.doi.org/10.1111/jvim.16248}, DOI={10.1111/jvim.16248}, abstractNote={Abstract Background Degenerative myelopathy (DM) in dogs shares similarities with superoxide dismutase 1‐associated human amyotrophic lateral sclerosis (ALS). Brain microstructural lesions are quantified using diffusion tensor imaging (DTI) in ALS patients. Objective Characterize brain neurodegenerative changes in DM‐affected dogs using DTI. Animals Sixteen DM‐affected and 8 control dogs. Methods Prospective observational study. Brain DTI was performed at baseline and every 3 months on DM‐affected dogs and compared to controls. Fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity were calculated on specified regions of interest. Gait scores (0, normal to 14, tetraplegia) were assigned at each scan. Diffusion tensor imaging values in DM‐affected dogs were compared to controls, gait scores, and evaluated over time. Results Mean age was 5.7 years (SD 3.2) in controls and 9.7 years (SD 1.4) in DM‐affected dogs. In DM‐affected dogs, mean baseline gait score was 4 (SD 1), and mean score change from baseline to last scan was 4.82 (SD 2.67). Nine dogs had ≤3 scans; 7 had >3 scans. Accounting for age, no differences in DTI indices were identified for any brain or proximal spinal cord regions between DM‐affected dogs and controls ( P > .05). Diffusion tensor imaging values poorly correlated with gait scores ( R 2 < .2). No significant changes were identified in diffusion indices over time ( P > .05). Conclusions and Clinical Importance Diffusion tensor imaging indices did not differentiate DM‐affected from control dogs, detect longitudinal changes, or differentiate disease severity. Findings do not yet support brain DTI as an imaging biomarker.}, number={5}, journal={Journal of Veterinary Internal Medicine}, publisher={Wiley}, author={Lewis, Melissa J. and Shomper, Jeremy L. and Williamson, Baye G. and Vansteenkiste, Daniella P. and Bibi, Katherine F. and Lim, Stefanie H. Y. and Kowal, Joseph B. and Coates, Joan R.}, year={2021}, month={Aug}, pages={2342–2349} } @article{lewis_shomper_williamson_vansteenkiste_bibi_lim_kowal_coates_2021, title={Brain diffusion tensor imaging in dogs with degenerative myelopathy}, volume={35}, ISSN={0891-6640 1939-1676}, url={http://dx.doi.org/10.1111/jvim.16248}, DOI={https://doi.org/10.1111/jvim.16248}, abstractNote={Abstract Background Degenerative myelopathy (DM) in dogs shares similarities with superoxide dismutase 1‐associated human amyotrophic lateral sclerosis (ALS). Brain microstructural lesions are quantified using diffusion tensor imaging (DTI) in ALS patients. Objective Characterize brain neurodegenerative changes in DM‐affected dogs using DTI. Animals Sixteen DM‐affected and 8 control dogs. Methods Prospective observational study. Brain DTI was performed at baseline and every 3 months on DM‐affected dogs and compared to controls. Fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity were calculated on specified regions of interest. Gait scores (0, normal to 14, tetraplegia) were assigned at each scan. Diffusion tensor imaging values in DM‐affected dogs were compared to controls, gait scores, and evaluated over time. Results Mean age was 5.7 years (SD 3.2) in controls and 9.7 years (SD 1.4) in DM‐affected dogs. In DM‐affected dogs, mean baseline gait score was 4 (SD 1), and mean score change from baseline to last scan was 4.82 (SD 2.67). Nine dogs had ≤3 scans; 7 had >3 scans. Accounting for age, no differences in DTI indices were identified for any brain or proximal spinal cord regions between DM‐affected dogs and controls ( P > .05). Diffusion tensor imaging values poorly correlated with gait scores ( R 2 < .2). No significant changes were identified in diffusion indices over time ( P > .05). Conclusions and Clinical Importance Diffusion tensor imaging indices did not differentiate DM‐affected from control dogs, detect longitudinal changes, or differentiate disease severity. Findings do not yet support brain DTI as an imaging biomarker.}, number={5}, journal={Journal of Veterinary Internal Medicine}, publisher={Wiley}, author={Lewis, Melissa J. and Shomper, Jeremy L. and Williamson, Baye G. and Vansteenkiste, Daniella P. and Bibi, Katherine F. and Lim, Stefanie H. Y. and Kowal, Joseph B. and Coates, Joan R.}, year={2021}, month={Aug}, pages={2342–2349} } @article{mehra_tolbert_moore_lewis_2021, title={Clinical Features and Risk Factors for Gastrointestinal Complications in Dogs Treated Surgically for Thoracolumbar Intervertebral Disc Extrusion}, volume={8}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2021.785228}, DOI={10.3389/fvets.2021.785228}, abstractNote={Gastrointestinal (GI) complications and their clinical implications are poorly characterized in dogs treated surgically for acute thoracolumbar intervertebral disc extrusion (TL-IVDE). The objective of this retrospective study was to characterize GI signs (including vomiting, diarrhea, melena, and hematochezia) in dogs undergoing hemilaminectomy for acute TL-IVDE. One-hundred and sixteen dogs were included. Frequency, type and severity of GI signs during hospitalization, duration of hospitalization and outcome were obtained from the medical record. Potential risk factors for the development of GI signs were explored using univariable and multivariable analyses. Gastrointestinal signs occurred in 55/116 dogs (47%); 22/55 dogs (40%) had one episode and 21/55 (38%) had ≥5 episodes. Diarrhea was the most common (40/55, 73%) while melena was rare (1/55, 2%). GI signs developed in 8/11 dogs (73%) treated perioperatively with both non-steroidal anti-inflammatories and corticosteroids with or without a washout period and in 25/52 dogs (48%) treated prophylactically with proton pump inhibitors. Median hospitalization was 7 days (4-15 days) vs. 5 days (4-11 days) in dogs with or without GI signs, respectively. Duration of hospitalization was associated with development of any GI signs, diarrhea and more severe GI signs (p = 0.001, 0.005, 0.021, respectively). Pre-operative paraplegia with absent pain perception was identified on univariable analysis (p = 0.005) and longer anesthetic duration on multivariable analysis to be associated with development of more severe GI signs (p = 0.047). In dogs undergoing surgery for acute TL-IVDE, GI signs were common and associated with duration of hospitalization and anesthesia. The influence of specific medications and neurologic severity on development of GI signs requires further investigation.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={Mehra, Jaya M. and Tolbert, M. Katherine and Moore, George E. and Lewis, Melissa J.}, year={2021}, month={Dec} } @article{hong_thomovsky_lewis_bentley_shelton_2021, title={Clinical characteristics of non‐infectious inflammatory myopathy in the boxer dog}, volume={62}, ISSN={0022-4510 1748-5827}, url={http://dx.doi.org/10.1111/jsap.13350}, DOI={10.1111/jsap.13350}, abstractNote={Objectives To evaluate the clinical characteristics, treatment, outcome and potential association between non‐infectious inflammatory myopathy and malignancy in boxer dogs. Materials and Methods Boxer dogs histologically diagnosed with non‐infectious inflammatory myopathy at the Comparative Neuromuscular Laboratory, University of California San Diego from 2010 to 2018 and with complete medical records were included in this retrospective study. Signalment, history, clinical signs, clinicopathologic findings, treatment and outcome were documented. Results Twenty‐eight boxer dogs with non‐infectious inflammatory myopathy, aged 1 to 11 years, were included. Eighteen were male (16 neutered; two entire) and 10 were female (seven spayed; three entire). Clinical signs included generalised weakness (n=17), dysphagia (n=11) and weight loss (n=10). Serum creatine kinase activity was elevated in all 20 cases tested (range 908 to 138,000 IU/L). One dog had undifferentiated round cell neoplastic infiltration within the muscle at the time of inflammatory myopathy diagnosis. Five dogs historically had mast cell tumours and 21 dogs were not diagnosed with neoplasia prior, at the time of or after inflammatory myopathy diagnosis. Treatment included glucocorticoid monotherapy (n=12), cyclosporine monotherapy (n=1) or multiple immune‐suppressive medications (n=14). Six dogs neurologically improved, 11 improved but relapsed while on treatment, seven did not improve. Eight dogs were euthanased, one died, four were lost to follow‐up. Clinical Significance Boxer dogs with non‐infectious inflammatory myopathy can present for generalised weakness and dysphagia; long‐term successful outcome is uncommon. The relationship between neoplasia and non‐infectious inflammatory myopathy in boxer dogs remains unclear; future prospective studies evaluating a larger cohort are warranted.}, number={9}, journal={Journal of Small Animal Practice}, publisher={Wiley}, author={Hong, H. P. and Thomovsky, S. A. and Lewis, M. J. and Bentley, R. T. and Shelton, G. D.}, year={2021}, month={May}, pages={765–774} } @article{linder_thomovsky_bowditch_lind_kazmierczak_breur_lewis_2021, title={Development of a simple method to measure static body weight distribution in neurologically and orthopedically normal mature small breed dogs}, volume={17}, ISSN={1746-6148}, url={http://dx.doi.org/10.1186/s12917-021-02808-x}, DOI={10.1186/s12917-021-02808-x}, abstractNote={Abstract Background Objective outcome measures capable of tracking different aspects of functional recovery in dogs with acute intervertebral disc herniation are needed to optimize physical rehabilitation protocols. Normal, pre-injury distribution of body weight in this population is unknown. The aims of this study were to quantify static weight distribution (SWD) using digital scales and to establish the feasibility of different scale methods in neurologically normal, mature, chondrodystrophic small breed dogs predisposed to intervertebral disc herniation. Results Twenty-five healthy, mature dogs were enrolled with a mean age of 4.6 years (SD 2.7) and a mean total body weight of 11.5 kg (SD 3.6). SWD for the thoracic and pelvic limbs and between individual limbs was acquired in triplicate and expressed as a percentage of total body weight using commercially available digital scales in four combinations: two bathroom, two kitchen (with thoracic and pelvic limbs combined), four bathroom and four kitchen (with limbs measured individually). SWD was also obtained using a pressure sensing walkway for comparison to scale data. Feasibility for each method was determined and coefficients of variation were used to calculate inter-trial variability. Mean SWD values were compared between methods using an ANOVA. The two bathroom scales method had the highest feasibility and lowest inter-trial variability and resulted in mean thoracic and pelvic limb SWD of 63 % (SD 3 %) and 37 % (SD 3 %), respectively. Thoracic limb mean SWD was higher for the PSW compared to any of the scale methods ( p < 0.0001). Conclusions SWD in a population of healthy chondrodystrophic dogs was simple to obtain using inexpensive and readily available digital scales. This study generated SWD data for subsequent comparison to dogs recovering from acute intervertebral disc herniation.}, number={1}, journal={BMC Veterinary Research}, publisher={Springer Science and Business Media LLC}, author={Linder, Jessica E. and Thomovsky, Stephanie and Bowditch, Jessica and Lind, Mallory and Kazmierczak, Kristine A. and Breur, Gert J. and Lewis, Melissa J.}, year={2021}, month={Mar} } @misc{linder_thomovsky_bowditch_lind_kazmierczak_breur_lewis_2021, title={Development of a simple method to measure static body weight distribution in orthopedically and neurologically normal mature small breed dogs}, url={http://dx.doi.org/10.21203/rs.3.rs-62185/v2}, DOI={https://doi.org/10.21203/rs.3.rs-62185/v2}, abstractNote={Abstract Background: Objective outcome measures capable of tracking different aspects of functional recovery in dogs with acute intervertebral disc herniation are needed to optimize physical rehabilitation protocols. Normal, pre-injury distribution of body weight in this population is unknown. The aims of this study were to quantify static weight distribution (SWD) using digital scales and to establish the feasibility of different scale methods in neurologically normal, mature, chondrodystrophic small breed dogs predisposed to intervertebral disc herniation. Results: Twenty-five healthy, mature dogs were enrolled with a mean age of 4.6 years (SD 2.7) and a mean total body weight of 11.5 kg (SD 3.6). SWD for the thoracic and pelvic limbs and between individual limbs was acquired in triplicate and expressed as a percentage of total body weight using commercially available digital scales in four combinations: two bathroom, two kitchen (with thoracic and pelvic limbs combined), four bathroom and four kitchen (with limbs measured individually). SWD was also obtained using a pressure sensing walkway for comparison to scale data. Feasibility for each method was determined and coefficients of variation were used to calculate inter-trial variability. Mean SWD values were compared between methods using an ANOVA. The two bathroom scales method had the highest feasibility and lowest inter-trial variability and resulted in mean thoracic and pelvic limb SWD of 63% (SD 3%) and 37% (SD 3%), respectively. Thoracic limb mean SWD was higher for the PSW compared to any of the scale methods (p<0.0001). Conclusions: SWD in a population of healthy chondrodystrophic dogs was simple to obtain using inexpensive and readily available digital scales. This study generated SWD data for subsequent comparison to dogs recovering from acute intervertebral disc herniation.}, publisher={Research Square Platform LLC}, author={Linder, Jessica E and Thomovsky, Stephanie and Bowditch, Jessica and Lind, Mallory and Kazmierczak, Kristine A and Breur, Gert J and Lewis, Melissa J}, year={2021}, month={Jan} } @article{lewis_jeffery_olby_2020, title={Ambulation in Dogs With Absent Pain Perception After Acute Thoracolumbar Spinal Cord Injury}, volume={7}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2020.00560}, DOI={10.3389/fvets.2020.00560}, abstractNote={Acute thoracolumbar spinal cord injury (SCI) is common in dogs frequently secondary to intervertebral disc herniation. Following severe injury, some dogs never regain sensory function to the pelvic limbs or tail and are designated chronically “deep pain negative.” Despite this, a subset of these dogs develop spontaneous motor recovery over time including some that recover sufficient function in their pelvic limbs to walk independently without assistance or weight support. This type of ambulation is commonly known as “spinal walking” and can take up to a year or more to develop. This review provides a comparative overview of locomotion and explores the physiology of locomotor recovery after severe SCI in dogs. We discuss the mechanisms by which post-injury plasticity and coordination between circuitry contained within the spinal cord, peripheral sensory feedback, and residual or recovered supraspinal connections might combine to underpin spinal walking. The clinical characteristics of spinal walking are outlined including what is known about the role of patient or injury features such as lesion location, timeframe post-injury, body size, and spasticity. The relationship between the emergence of spinal walking and electrodiagnostic and magnetic resonance imaging findings are also discussed. Finally, we review possible ways to predict or facilitate recovery of walking in chronically deep pain negative dogs. Improved understanding of the mechanisms of gait generation and plasticity of the surviving tissue after injury might pave the way for further treatment options and enhanced outcomes in severely injured dogs.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={Lewis, Melissa J. and Jeffery, Nick D. and Olby, Natasha J.}, year={2020}, month={Aug} } @article{bray_early_olby_lewis_2020, title={An update on hemilaminectomy of the cranial thoracic spine: Review of six cases}, volume={10}, ISSN={2218-6050 2226-4485}, url={http://dx.doi.org/10.4314/ovj.v10i1.4}, DOI={10.4314/ovj.v10i1.4}, abstractNote={Background: The optimal surgical approach to relieve spinal cord compression in the cranial thoracic spine is not well described, and the anatomy of the cranial thoracic vertebrae creates added surgical difficulty.Aim: This study describes the surgical approach, treatment, and outcome of three dogs and three cats that underwent a cranial thoracic hemilaminectomy for the treatment of extradural spinal cord compression. Surgical positioning was tailored to avoid extensive dissection and provide for a restricted, careful approach.Methods: Three dogs and three cats presenting for cranial thoracic spinal cord compression requiring surgical intervention were included.Results: All patients were discharged within 5 days. No patients experienced postoperative deterioration in neurologic status, and four animals had improved neurologic status at discharge.Conclusion: In cases with cranial thoracic spinal cord compression, the spinous processes can be spared, extensive muscle dissection minimized, and successful outcomes achieved with the appropriate positioning and limited approach. Keywords: Hemilaminectomy, Intervertebral Disc Disease, Myelopathy, Thoracic.}, number={1}, journal={Open Veterinary Journal}, publisher={ScopeMed}, author={Bray, Kathryn Y. and Early, Peter J. and Olby, Natasha J. and Lewis, Melissa J.}, year={2020}, month={Apr} } @article{bray_early_olby_lewis_2020, title={An update on hemilaminectomy of the cranial thoracic spine: Review of six cases}, volume={10}, ISSN={2218-6050 2226-4485}, url={http://dx.doi.org/10.4314/ovj.v10i1.4}, DOI={https://doi.org/10.4314/ovj.v10i1.4}, abstractNote={Background: The optimal surgical approach to relieve spinal cord compression in the cranial thoracic spine is not well described, and the anatomy of the cranial thoracic vertebrae creates added surgical difficulty.Aim: This study describes the surgical approach, treatment, and outcome of three dogs and three cats that underwent a cranial thoracic hemilaminectomy for the treatment of extradural spinal cord compression. Surgical positioning was tailored to avoid extensive dissection and provide for a restricted, careful approach.Methods: Three dogs and three cats presenting for cranial thoracic spinal cord compression requiring surgical intervention were included.Results: All patients were discharged within 5 days. No patients experienced postoperative deterioration in neurologic status, and four animals had improved neurologic status at discharge.Conclusion: In cases with cranial thoracic spinal cord compression, the spinous processes can be spared, extensive muscle dissection minimized, and successful outcomes achieved with the appropriate positioning and limited approach. Keywords: Hemilaminectomy, Intervertebral Disc Disease, Myelopathy, Thoracic.}, number={1}, journal={Open Veterinary Journal}, publisher={ScopeMed}, author={Bray, Kathryn Y. and Early, Peter J. and Olby, Natasha J. and Lewis, Melissa J.}, year={2020}, month={Apr} } @article{granger_olby_nout-lomas_2020, title={Bladder and Bowel Management in Dogs With Spinal Cord Injury}, volume={7}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2020.583342}, DOI={10.3389/fvets.2020.583342}, abstractNote={Spinal cord injury in companion dogs can lead to urinary and fecal incontinence or retention, depending on the severity, and localization of the lesion along the canine nervous system. The bladder and gastrointestinal dysfunction caused by lesions of the autonomic system can be difficult to recognize, interpret and are easily overlooked. Nevertheless, it is crucial to maintain a high degree of awareness of the impact of micturition and defecation disturbances on the animal's condition, welfare and on the owner. The management of these disabilities is all the more challenging that the autonomic nervous system physiology is a complex topic. In this review, we propose to briefly remind the reader the physiology of micturition and defecation in dogs. We then present the bladder and gastrointestinal clinical signs associated with sacral lesions (i.e., the L7-S3 spinal cord segments and nerves) and supra-sacral lesions (i.e., cranial to the L7 spinal cord segment), largely in the context of intervertebral disc herniation. We summarize what is known about the natural recovery of urinary and fecal continence in dogs after spinal cord injury. In particular we review the incidence of urinary tract infection after injury. We finally explore the past and recent literature describing management of urinary and fecal dysfunction in the acute and chronic phase of spinal cord injury. This comprises medical therapies but importantly a number of surgical options, some known for decades such as sacral nerve stimulation, that might spark some interest in the field of spinal cord injury in companion dogs.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={Granger, Nicolas and Olby, Natasha J. and Nout-Lomas, Yvette S.}, year={2020}, month={Nov} } @article{fenn_olby_2020, title={Classification of Intervertebral Disc Disease}, volume={7}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2020.579025}, DOI={10.3389/fvets.2020.579025}, abstractNote={Intervertebral disc disease (IVDD) has been recognized in dogs since the 1800s, when the first descriptions of extruded disc material within the vertebral canal were published. In the intervening time our understanding of intervertebral disc pathology in dogs and cats has increased dramatically, with many variations of IVDD described. Whilst the volume of literature and collective understanding of IVDD has expanded, there has also been scope for confusion as the definition of intervertebral disc disease, with its myriad different manifestations, becomes more complicated. A large volume of literature has aimed to combine the use of histopathology, diagnostic imaging and clinical findings to better understand the various ways in which IVDD can be classified. Much of this research has focused on the classification of mechanisms of intervertebral disc degeneration, centering around the differences between, and overlaps in, IVDD in chondrodystrophic and non-chondrodystrophic dog breeds. However, with the increasing availability of advanced imaging modalities allowing more accurate antemortem diagnosis, the concept of IVDD has expanded to include other clinical presentations that may not fit into traditional models of classification of IVDD. This review aims to provide an up to date overview of both historical and current systems of IVDD classification, highlighting the important findings and controversies underpinning them.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={Fenn, Joe and Olby, Natasha J.}, year={2020}, month={Oct} } @article{jeffery_olby_moore_2020, title={Clinical Trial Design—A Review—With Emphasis on Acute Intervertebral Disc Herniation}, volume={7}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2020.00583}, DOI={10.3389/fvets.2020.00583}, abstractNote={There is a clear need for new methods of treatment of acute disc herniation in dogs, most obviously to address the permanent loss of function that can arise because of the associated spinal cord injury. Clinical trials form the optimal method to introduce new therapies into everyday clinical practice because they are a reliable source of unbiased evidence of effectiveness. Although many designs are available, parallel cohort trials are most widely applicable to acute disc herniation in dogs. In this review another key trial design decision—that between pragmatic and explanatory approaches—is highlighted and used as a theme to illustrate the close relationship between trial objective and design. Acute disc herniation, and acute spinal cord injury, is common in dogs and there is a multitude of candidate interventions that could be trialed. Most current obstacles to large-scale clinical trials in dogs can be overcome by collaboration and cooperation amongst interested veterinarians.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={Jeffery, Nick D. and Olby, Natasha J. and Moore, Sarah A.}, year={2020}, month={Sep} } @article{moore_tipold_olby_stein_granger_2020, title={Current Approaches to the Management of Acute Thoracolumbar Disc Extrusion in Dogs}, volume={7}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2020.00610}, DOI={10.3389/fvets.2020.00610}, abstractNote={Intervertebral disc extrusion (IVDE) is one of the most common neurologic problems encountered in veterinary clinical practice. The purpose of this manuscript is to provide an overview of the literature related to treatment of acute canine thoracolumbar IVDE to help construct a framework for standard care of acute canine thoracolumbar IVDE where sufficient evidence exists and to highlight opportunities for future prospective veterinary clinical research useful to strengthen care recommendations in areas where evidence is low or non-existent. While there exist a number of gaps in the veterinary literature with respect to standards of care for dogs with acute thoracolumbar IVDE, recommendations for standard care can be made in some areas, particularly with respect to surgical decompression where the currently available evidence supports that surgery should be recommended for dogs with nonambulatory paraparesis or worse. While additional information is needed about the influence on timing of decompression on outcome in dogs that are deep pain negative for longer than 48 h duration, there is no evidence to support treatment of the 48 h time point as a cut off beyond which it becomes impossible for dogs to achieve locomotor recovery. Surgical decompression is best accomplished by either hemilaminectomy or mini-hemilaminectomy and fenestration of, at a minimum, the acutely ruptured disc. Adjacent discs easily accessed by way of the same approach should be considered for fenestration given the evidence that this substantially reduces future herniation at fenestrated sites. Currently available neuroprotective strategies such as high does MPSS and PEG are not recommended due to lack of demonstrated treatment effect in randomized controlled trials, although the role of anti-inflammatory steroids as a protective strategy against progressive myelomalacia and the question of whether anti-inflammatory steroids or NSAIDs provide superior medical therapy require further evaluation.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={Moore, Sarah A. and Tipold, Andrea and Olby, Natasha J. and Stein, Veronica and Granger, Nicolas}, year={2020}, month={Sep} } @article{spitzbarth_moore_stein_levine_kühl_gerhauser_baumgärtner_2020, title={Current Insights Into the Pathology of Canine Intervertebral Disc Extrusion-Induced Spinal Cord Injury}, volume={7}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2020.595796}, DOI={10.3389/fvets.2020.595796}, abstractNote={Spinal cord injury (SCI) in dogs is commonly attributed to intervertebral disc extrusion (IVDE). Over the last years substantial progress was made in the elucidation of factors contributing to the pathogenesis of this common canine disease. A detailed understanding of the underlying histopathological and molecular alterations in the lesioned spinal cord represents a prerequisite to translate knowledge on the time course of secondary injury processes into the clinical setting. This review summarizes the current state of knowledge of the underlying pathology of canine IVDE-related SCI. Pathological alterations in the spinal cord of dogs affected by IVDE-related SCI include early and persisting axonal damage and glial responses, dominated by phagocytic microglia/macrophages. These processes are paralleled by a pro-inflammatory microenvironment with dysregulation of cytokines and matrix metalloproteinases within the spinal cord. These data mirror findings from a clinical and therapeutic perspective and can be used to identify biomarkers that are able to more precisely predict the clinical outcome. The pathogenesis of progressive myelomalacia, a devastating complication of SCI in dogs, is not understood in detail so far; however, a fulminant and exaggerating secondary injury response with massive reactive oxygen species formation seems to be involved in this unique neuropathological entity. There are substantial gaps in the knowledge of pathological changes in IVDE with respect to more advanced and chronic lesions and the potential involvement of demyelination. Moreover, the role of microglia/macrophage polarization in IVDE-related SCI still remains to be investigated. A close collaboration of clinical neurologists and veterinary pathologists will help to facilitate an integrative approach to a more detailed understanding of the molecular pathogenesis of canine IVDE and thus to identify therapeutic targets.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={Spitzbarth, Ingo and Moore, Sarah A. and Stein, Veronika M. and Levine, Jonathan M. and Kühl, Bianca and Gerhauser, Ingo and Baumgärtner, Wolfgang}, year={2020}, month={Oct} } @misc{linder_thomovsky_bowditch_lind_kazmierczak_breur_lewis_2020, title={Development of a Simple Method to Measure Static Body Weight Distribution in Neurologically Normal Small Breed Dogs}, url={http://dx.doi.org/10.21203/rs.3.rs-62185/v1}, DOI={https://doi.org/10.21203/rs.3.rs-62185/v1}, abstractNote={Abstract Background: Objective outcome measures capable of tracking different aspects of functional recovery in dogs with acute intervertebral disc herniation are needed to optimize physical rehabilitation protocols. Normal, pre-injury distribution of body weight in this population is unknown. The aims of this study were to quantify static weight distribution (SWD) using digital scales and to establish the feasibility of different scale methods in neurologically normal, chondrodystrophic small breed dogs predisposed to intervertebral disc herniation. Results: Twenty-five healthy dogs were enrolled with a mean age of 4.6 years (SD 2.7) and a mean total body weight of 11.5 kg (SD 3.6). SWD for the thoracic and pelvic limbs and between individual limbs was acquired in triplicate and expressed as a percentage of total body weight using commercially available digital scales in four combinations: two bathroom, two kitchen (with thoracic and pelvic limbs combined), four bathroom and four kitchen (with limbs measured individually). SWD was also obtained using a pressure sensing walkway for comparison to scale data. Feasibility for each method was determined and coefficients of variation were used to calculate inter-trial variability. Mean SWD values were compared between methods using an ANOVA. The two bathroom scales method had the highest feasibility and lowest inter-trial variability and resulted in mean thoracic and pelvic limb SWD of 63% (SD 3%) and 37% (SD 3%), respectively. Thoracic limb mean SWD was higher for the PSW compared to any of the scale methods (p<0.0001). Conclusions: SWD in a population of healthy chondrodystrophic dogs was simple to obtain using inexpensive and readily available digital scales. This study generated SWD data for subsequent comparison to dogs recovering from acute intervertebral disc herniation.}, publisher={Research Square Platform LLC}, author={Linder, Jessica E and Thomovsky, Stephanie and Bowditch, Jessica and Lind, Mallory and Kazmierczak, Kristine A and Breur, Gert J and Lewis, Melissa J}, year={2020}, month={Sep} } @article{da costa_de decker_lewis_volk_2020, title={Diagnostic Imaging in Intervertebral Disc Disease}, volume={7}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2020.588338}, DOI={10.3389/fvets.2020.588338}, abstractNote={Imaging is integral in the diagnosis of canine intervertebral disc disease (IVDD) and in differentiating subtypes of intervertebral disc herniation (IVDH). These include intervertebral disc extrusion (IVDE), intervertebral disc protrusion (IVDP) and more recently recognized forms such as acute non-compressive nucleus pulposus extrusion (ANNPE), hydrated nucleus pulposus extrusion (HNPE), and intradural/intramedullary intervertebral disc extrusion (IIVDE). Many imaging techniques have been described in dogs with roles for survey radiographs, myelography, computed tomography (CT), and magnetic resonance imaging (MRI). Given how common IVDH is in dogs, a thorough understanding of the indications and limitations for each imaging modality to aid in diagnosis, treatment planning and prognosis is essential to successful case management. While radiographs can provide useful information, especially for identifying intervertebral disc degeneration or calcification, there are notable limitations. Myelography addresses some of the constraints of survey radiographs but has largely been supplanted by cross-sectional imaging. Computed tomography with or without myelography and MRI is currently utilized most widely and have become the focus of most contemporary studies on this subject. Novel advanced imaging applications are being explored in dogs but are not yet routinely performed in clinical patients. The following review will provide a comprehensive overview on common imaging modalities reported to aid in the diagnosis of IVDH including IVDE, IVDP, ANNPE, HNPE, and IIVDE. The review focuses primarily on canine IVDH due to its frequency and vast literature as opposed to feline IVDH.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={da Costa, Ronaldo C. and De Decker, Steven and Lewis, Melissa J. and Volk, Holger}, year={2020}, month={Oct} } @article{lewis_granger_jeffery_2020, title={Emerging and Adjunctive Therapies for Spinal Cord Injury Following Acute Canine Intervertebral Disc Herniation}, volume={7}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2020.579933}, DOI={10.3389/fvets.2020.579933}, abstractNote={Some dogs do not make a full recovery following medical or surgical management of acute canine intervertebral disc herniation (IVDH), highlighting the limits of currently available treatment options. The multitude of difficulties in treating severe spinal cord injury are well-recognized, and they have spurred intense laboratory research, resulting in a broad range of strategies that might have value in treating spinal cord-injured dogs. These include interventions that aim to directly repair the spinal cord lesion, promote axonal sparing or regeneration, mitigate secondary injury through neuroprotective mechanisms, or facilitate functional compensation. Despite initial promise in experimental models, many of these techniques have failed or shown mild efficacy in clinical trials in humans and dogs, although high quality evidence is lacking for many of these interventions. However, the continued introduction of new options to the veterinary clinic remains important for expanding our understanding of the mechanisms of injury and repair and for development of novel and combined strategies for severely affected dogs. This review outlines adjunctive or emerging therapies that have been proposed as treatment options for dogs with acute IVDH, including discussion of local or lesion-based approaches as well as systemically applied treatments in both acute and subacute-to-chronic settings. These interventions include low-level laser therapy, electromagnetic fields or oscillating electrical fields, adjunctive surgical techniques (myelotomy or durotomy), systemically or locally-applied hypothermia, neuroprotective chemicals, physical rehabilitation, hyperbaric oxygen therapy, electroacupuncture, electrical stimulation of the spinal cord or specific peripheral nerves, nerve grafting strategies, 4-aminopyridine, chondroitinase ABC, and cell transplantation.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={Lewis, Melissa J. and Granger, Nicolas and Jeffery, Nick D.}, year={2020}, month={Oct} } @article{lewis_early_mariani_munana_olby_2020, title={Influence of Duration of Injury on Diffusion Tensor Imaging in Acute Canine Spinal Cord Injury}, volume={37}, ISSN={["1557-9042"]}, DOI={10.1089/neu.2019.6786}, abstractNote={Diffusion tensor imaging (DTI) quantifies microstructural lesion characteristics but impact of the interval between spinal cord injury (SCI) and examination on imaging characteristics is unclear. Our objective was to investigate the impact of duration of injury on DTI indices in dogs with acute, spontaneous SCI due to thoracolumbar intervertebral disc herniation (IVDH) and explore associations with clinical severity. Twenty-six dogs with acute thoracolumbar IVDH of variable severity who underwent DTI were included. Neurologic severity was graded using the Modified Frankel Score (0-V). Fractional anisotropy (FA) and mean diffusivity (MD) were calculated on regions of interest within and adjacent to the lesion epicenter. Relationships between FA or MD and duration (injury to imaging interval) or neurologic severity were determined using regression analysis and Wilcoxon rank sum. Median age was 6.8 years (1-13), median duration was 1.5 days (1-9) and neurologic signs ranged from ambulatory paraparesis (MFS II) to paraplegia with absent pain perception (MFS V). Mean FA was 0.61+/-0.09 cranial to the lesion, 0.57+/-0.12 at the epicenter and 0.55+/-0.10 caudally. Mean MD was 1.18x10-3+/-0.0002 cranially, 1.09x10-3+/-0.0002 at the epicenter and 1.14x10-3+/-0.0002 caudally. Accounting for neurologic severity and age, FA caudal to the epicenter decreased with increasing duration of injury (p = 0.02). Lower MD within the lesion epicenter was associated with worse neurologic severity (p = 0.01). Duration of injury should be considered when interpreting DTI results in dogs with acute thoracolumbar IVDH. MD might differentiate injury severity in the acute setting and be worthy of development as an imaging biomarker.}, number={21}, journal={JOURNAL OF NEUROTRAUMA}, author={Lewis, Melissa J. and Early, Peter J. and Mariani, Christopher L. and Munana, Karen R. and Olby, Natasha J.}, year={2020}, month={Nov}, pages={2261–2267} } @article{lewis_early_mariani_munana_olby_2020, title={Influence of Duration of Injury on Diffusion Tensor Imaging in Acute Canine Spinal Cord Injury}, volume={37}, ISSN={0897-7151 1557-9042}, url={http://dx.doi.org/10.1089/neu.2019.6786}, DOI={https://doi.org/10.1089/neu.2019.6786}, abstractNote={Diffusion tensor imaging (DTI) quantifies microstructural lesion characteristics, but impact of the interval between spinal cord injury (SCI) and examination on imaging characteristics is unclear. Our objective was to investigate the impact of duration of injury on DTI indices in dogs with acute, spontaneous SCI from thoracolumbar intervertebral disc herniation (IVDH) and explore associations with clinical severity. Twenty-six dogs with acute thoracolumbar IVDH of variable severity who underwent DTI were included. Neurological severity was graded using the modified Frankel Score (0-V). Fractional anisotropy (FA) and mean diffusivity (MD) were calculated on regions of interest within and adjacent to the lesion epicenter. Relationships between FA or MD and duration (injury to imaging interval) or neurological severity were determined using regression analysis and Wilcoxon rank sum. Median age was 6.8 years (1-13), median duration was 1.5 days (1-9), and neurological signs ranged from ambulatory paraparesis (MFS II) to paraplegia with absent pain perception (MFS V). Mean FA was 0.61 ± 0.09 cranial to the lesion, 0.57 ± 0.12 at the epicenter and 0.55 ± 0.10 caudally. Mean MD was 1.18 × 10-3 ± 0.0002 cranially, 1.09 × 10-3 ± 0.0002 at the epicenter, and 1.14 × 10-3 ± 0.0002 caudally. Accounting for neurological severity and age, FA caudal to the epicenter decreased with increasing duration of injury (p = 0.02). Lower MD within the lesion epicenter was associated with worse neurological severity (p = 0.01). Duration of injury should be considered when interpreting DTI results in dogs with acute thoracolumbar IVDH. The MD might differentiate injury severity in the acute setting and be worthy of development as an imaging biomarker.}, number={21}, journal={Journal of Neurotrauma}, publisher={Mary Ann Liebert Inc}, author={Lewis, Melissa J. and Early, Peter J. and Mariani, Christopher L. and Munana, Karen R. and Olby, Natasha J.}, year={2020}, month={Nov}, pages={2261–2267} } @article{crawford_dreger_shelton_ekenstedt_lewis_2020, title={Juvenile‐onset motor polyneuropathy in Siberian cats}, volume={34}, ISSN={0891-6640 1939-1676}, url={http://dx.doi.org/10.1111/jvim.15963}, DOI={10.1111/jvim.15963}, abstractNote={Abstract Background Polyneuropathies are infrequently described in cats. There is a genetic predisposition in several breeds. Objective To clinically characterize a novel motor polyneuropathy in a family of Siberian cats. Animals Thirteen closely related Siberian cats, 4 clinically affected and 9 clinically unaffected individuals. Methods Retrospective study. Clinical data and pedigree information were obtained from the medical records and breeder. Electrodiagnostic testing and muscle and peripheral nerve biopsy samples were obtained from 1 affected cat. Follow‐up information was obtained for all affected cats. Results Onset of signs was 4 to 10 months in affected cats. Clinical signs were progressive or waxing/waning neuromuscular weakness (4/4), normal sensory function (4/4), and variably decreased withdrawal reflexes (3/4). All cats returned to normal neurologic function within 1 to 4 weeks. All cats had a recurrence of weakness (3/4 had 1 recurrent episode, 1/4 had 3 relapses) from which they recovered fully. In 1 cat, electromyography and motor nerve conduction studies showed multicentric spontaneous activity, normal motor nerve conduction velocity, reduced compound muscle action potential amplitude, and polyphasia. Histologic evaluation of muscle and nerve in that cat showed mild muscle atrophy consistent with recent denervation, endoneurial and perineurial edema, and mild mononuclear cell infiltration within intramuscular nerve branches and a peripheral nerve. Pedigree analysis suggests an autosomal recessive mode of inheritance, although neither a genetically complex/polygenic condition nor an acquired inflammatory polyneuropathy can be ruled‐out. Conclusions and Clinical Importance We describe a motor polyneuropathy in juvenile Siberian cats characterized by self‐limiting weakness with potential relapse.}, number={6}, journal={Journal of Veterinary Internal Medicine}, publisher={Wiley}, author={Crawford, Kelly C. and Dreger, Dayna L. and Shelton, G. Diane and Ekenstedt, Kari J. and Lewis, Melissa J.}, year={2020}, month={Nov}, pages={2595–2604} } @article{crawford_dreger_shelton_ekenstedt_lewis_2020, title={Juvenile‐onset motor polyneuropathy in Siberian cats}, volume={34}, ISSN={0891-6640 1939-1676}, url={http://dx.doi.org/10.1111/jvim.15963}, DOI={https://doi.org/10.1111/jvim.15963}, abstractNote={Abstract Background Polyneuropathies are infrequently described in cats. There is a genetic predisposition in several breeds. Objective To clinically characterize a novel motor polyneuropathy in a family of Siberian cats. Animals Thirteen closely related Siberian cats, 4 clinically affected and 9 clinically unaffected individuals. Methods Retrospective study. Clinical data and pedigree information were obtained from the medical records and breeder. Electrodiagnostic testing and muscle and peripheral nerve biopsy samples were obtained from 1 affected cat. Follow‐up information was obtained for all affected cats. Results Onset of signs was 4 to 10 months in affected cats. Clinical signs were progressive or waxing/waning neuromuscular weakness (4/4), normal sensory function (4/4), and variably decreased withdrawal reflexes (3/4). All cats returned to normal neurologic function within 1 to 4 weeks. All cats had a recurrence of weakness (3/4 had 1 recurrent episode, 1/4 had 3 relapses) from which they recovered fully. In 1 cat, electromyography and motor nerve conduction studies showed multicentric spontaneous activity, normal motor nerve conduction velocity, reduced compound muscle action potential amplitude, and polyphasia. Histologic evaluation of muscle and nerve in that cat showed mild muscle atrophy consistent with recent denervation, endoneurial and perineurial edema, and mild mononuclear cell infiltration within intramuscular nerve branches and a peripheral nerve. Pedigree analysis suggests an autosomal recessive mode of inheritance, although neither a genetically complex/polygenic condition nor an acquired inflammatory polyneuropathy can be ruled‐out. Conclusions and Clinical Importance We describe a motor polyneuropathy in juvenile Siberian cats characterized by self‐limiting weakness with potential relapse.}, number={6}, journal={Journal of Veterinary Internal Medicine}, publisher={Wiley}, author={Crawford, Kelly C. and Dreger, Dayna L. and Shelton, G. Diane and Ekenstedt, Kari J. and Lewis, Melissa J.}, year={2020}, month={Nov}, pages={2595–2604} } @article{olby_da costa_levine_stein_2020, title={Prognostic Factors in Canine Acute Intervertebral Disc Disease}, volume={7}, ISSN={2297-1769}, url={http://dx.doi.org/10.3389/fvets.2020.596059}, DOI={10.3389/fvets.2020.596059}, abstractNote={Knowledge of the prognosis of acute spinal cord injury is critical to provide appropriate information for clients and make the best treatment choices. Acute intervertebral disc extrusions (IVDE) are a common cause of pain and paralysis in dogs with several types of IVDE occurring. Important prognostic considerations are recovery of ambulation, return of urinary and fecal continence, resolution of pain and, on the negative side, development of progressive myelomalacia. Initial injury severity affects prognosis as does type of IVDE, particularly when considering recovery of continence. Overall, loss of deep pain perception signals a worse outcome. When considering Hansen type 1 IVDE, the prognosis is altered by the choice of surgical vs. medical therapy. Concentration of structural proteins in the plasma, as well as inflammatory mediators, creatine kinase, and myelin basic protein in the cerebrospinal fluid (CSF) can provide additional prognostic information. Finally, cross-sectional area and length of T2 hyperintensity and loss of HASTE signal on MRI have been associated with outcome. Future developments in plasma and imaging biomarkers will assist in accurate prognostication and optimization of patient management.}, journal={Frontiers in Veterinary Science}, publisher={Frontiers Media SA}, author={Olby, Natasha J. and da Costa, Ronaldo C. and Levine, Jon M. and Stein, Veronika M.}, year={2020}, month={Nov} } @article{schreeg_evans_allen_lewis_luckring_evola_richard_piner_thompson_adin_et al._2019, title={Cardiac Leiomyosarcoma in a Cat Presenting for Bilateral Renal Neoplasia}, volume={168}, ISSN={["1532-3129"]}, DOI={10.1016/j.jcpa.2019.02.005}, abstractNote={A 10-year-old neutered female domestic longhair cat was presented to a tertiary care veterinary hospital for evaluation of a right renal mass that was identified incidentally on abdominal radiographs and classified further as a sarcoma based on fine needle aspiration cytology. Further diagnostic workup, including ultrasound and cytology, identified a sarcoma in the left kidney. After approximately 1 month of conservative medical management, the clinical condition deteriorated and the cat was humanely destroyed. Post-mortem examination confirmed bilateral renal masses with multifocal infarction and extensive necrosis, and further identified a large mass at the apex of the heart as well as multiple pulmonary nodules. Microscopical examination of the masses identified a population of poorly-differentiated neoplastic spindle cells, consistent with sarcoma. Immunohistochemically, the neoplastic cells expressed smooth muscle actin and muscle-specific actin, but were negative for myoglobin and factor VIII. Phosphotungstic acid-haematoxylin staining was unable to identify cross-striations in the neoplastic cells. Based on these results and the pattern of lesion distribution, the cat was diagnosed with cardiac leiomyosarcoma with pulmonary and bilateral renal metastasis.}, journal={JOURNAL OF COMPARATIVE PATHOLOGY}, author={Schreeg, M. E. and Evans, B. J. and Allen, J. and Lewis, M. C. and Luckring, E. and Evola, M. and Richard, D. K. and Piner, K. and Thompson, E. M. and Adin, D. B. and et al.}, year={2019}, month={Apr}, pages={19–24} } @article{lewis_williams_langley_jarvis_sawicki_olby_2019, title={Development of a Novel Gait Analysis Tool Measuring Center of Pressure for Evaluation of Canine Chronic Thoracolumbar Spinal Cord Injury}, volume={36}, ISSN={0897-7151 1557-9042}, url={http://dx.doi.org/10.1089/neu.2019.6479}, DOI={10.1089/neu.2019.6479}, abstractNote={Gait evaluation after spinal cord injury (SCI) is an important component of determining functional status. Analysis of center of pressure (COP) provides a dynamic reflection of global locomotion and postural control and has been used to quantify various gait abnormalities. We hypothesized that COP variability would be greater for SCI versus normal dogs and that COP would be able to differentiate varying injury severity. Our objective was to investigate COP, COP variability, and body weight support percentage in dogs with chronic SCI. Eleven chronically non-ambulatory dogs after acute severe thoracolumbar SCI were enrolled. COP measurements in x (right-to-left, COPx) and y (craniocaudal, COPy) directions were captured while dogs walked on a pressure-sensitive treadmill with pelvic limb sling support. Root mean square values (RMS_COPx and RMS_COPy) were calculated to assess variability in COP. Body weight support percentage was measured using a load cell. Gait also was quantified using an open field scale (OFS) and treadmill-based stepping and coordination scores (SS, RI). Mean COPx, COPy, RMS_COPx, and RMS_COPy were compared between dogs with SCI and previously evaluated healthy controls. RMS measurements and support percentage were compared with standard gait scales (OFS, SS, RI). Mean COPy was more cranial and RMS_COPx and RMS_COPy were greater in SCI versus normal dogs (p < 0.001). Support percentage moderately correlated with SS (p = 0.019; R2 = 0.47). COP analysis and body weight support measurements offer information about post-injury locomotion. Further development is needed before consideration as an outcome measure to complement validated gait analysis methods in dogs with SCI.}, number={21}, journal={Journal of Neurotrauma}, publisher={Mary Ann Liebert Inc}, author={Lewis, Melissa J. and Williams, Kimberly D. and Langley, Taylor and Jarvis, Leighanne M. and Sawicki, Gregory S. and Olby, Natasha J.}, year={2019}, month={Nov}, pages={3018–3025} } @article{lewis_williams_langley_jarvis_sawicki_olby_2019, title={Development of a Novel Gait Analysis Tool Measuring Center of Pressure for Evaluation of Canine Chronic Thoracolumbar Spinal Cord Injury}, volume={36}, ISSN={0897-7151 1557-9042}, url={http://dx.doi.org/10.1089/neu.2019.6479}, DOI={https://doi.org/10.1089/neu.2019.6479}, abstractNote={Gait evaluation after spinal cord injury (SCI) is an important component of determining functional status. Analysis of center of pressure (COP) provides a dynamic reflection of global locomotion and postural control and has been used to quantify various gait abnormalities. We hypothesized that COP variability would be greater for SCI versus normal dogs and that COP would be able to differentiate varying injury severity. Our objective was to investigate COP, COP variability, and body weight support percentage in dogs with chronic SCI. Eleven chronically non-ambulatory dogs after acute severe thoracolumbar SCI were enrolled. COP measurements in x (right-to-left, COPx) and y (craniocaudal, COPy) directions were captured while dogs walked on a pressure-sensitive treadmill with pelvic limb sling support. Root mean square values (RMS_COPx and RMS_COPy) were calculated to assess variability in COP. Body weight support percentage was measured using a load cell. Gait also was quantified using an open field scale (OFS) and treadmill-based stepping and coordination scores (SS, RI). Mean COPx, COPy, RMS_COPx, and RMS_COPy were compared between dogs with SCI and previously evaluated healthy controls. RMS measurements and support percentage were compared with standard gait scales (OFS, SS, RI). Mean COPy was more cranial and RMS_COPx and RMS_COPy were greater in SCI versus normal dogs (p < 0.001). Support percentage moderately correlated with SS (p = 0.019; R2 = 0.47). COP analysis and body weight support measurements offer information about post-injury locomotion. Further development is needed before consideration as an outcome measure to complement validated gait analysis methods in dogs with SCI.}, number={21}, journal={Journal of Neurotrauma}, publisher={Mary Ann Liebert Inc}, author={Lewis, Melissa J. and Williams, Kimberly D. and Langley, Taylor and Jarvis, Leighanne M. and Sawicki, Gregory S. and Olby, Natasha J.}, year={2019}, month={Nov}, pages={3018–3025} } @article{trumpp_parsley_lewis_camp_taylor_2019, title={Presumptive tick paralysis in 2 American Miniature horses in the United States}, volume={33}, ISSN={0891-6640 1939-1676}, url={http://dx.doi.org/10.1111/jvim.15540}, DOI={10.1111/jvim.15540}, abstractNote={AbstractRationaleTick paralysis has not been reported in horses in North America.Clinical FindingsTwo American Miniature horses were examined for progressive weakness and recumbency. Numerous ticks (Dermacentor variabilis) were found on both horses. Horse 1 was recumbent (grade 5/5 gait deficit) on presentation, whereas Horse 2 was standing but ataxic (grade 4/5 gait deficit) and tetraparetic. Both horses had decreased tongue and tail muscle tone, and had normal spinal reflexes. Cerebrospinal fluid cytology was normal. Equine herpesvirus‐1 testing was negative.Pertinent InterventionsTicks were removed within 24 hours of presentation. Both horses were treated topically with permethrin. Supportive care included fluid therapy, treatment for corneal ulceration, and frequent repositioning during recumbency.OutcomeWithin 48 hours of tick removal, both horses were neurologically normal.Clinical RelevanceOurs is the first reported case of presumptive tick paralysis in horses in North America. Although rare, tick paralysis should be considered in horses presented with acute‐onset weakness progressing to recumbency.}, number={4}, journal={Journal of Veterinary Internal Medicine}, publisher={Wiley}, author={Trumpp, Kelsey M. and Parsley, Ashley L. and Lewis, Melissa J. and Camp, Joseph W., Jr. and Taylor, Sandra D.}, year={2019}, month={Jun}, pages={1784–1788} } @inbook{lewis_2019, place={St. Louis, MO}, edition={4th}, title={Spinal Cord Injury}, ISBN={9780323554510}, booktitle={Cote’s Clinical Veterinary Advisor: Dogs and Cats}, publisher={Mosby}, author={Lewis, M.J.}, editor={Cohn, L. and Cote, E.Editors}, year={2019} } @article{lewis_laber_olby_2019, title={Predictors of Response to 4-Aminopyridine in Chronic Canine Spinal Cord Injury}, volume={36}, ISSN={0897-7151 1557-9042}, url={http://dx.doi.org/10.1089/neu.2018.5975}, DOI={10.1089/neu.2018.5975}, abstractNote={4-Aminopyridine (4AP), a potassium channel antagonist, can improve hindlimb motor function in dogs with chronic thoracolumbar spinal cord injury (SCI); however, individual response is variable. We hypothesized that injury characteristics would differ between dogs that do and do not respond to 4AP. Our objective was to compare clinical, electrodiagnostic, gait, and imaging variables between dogs that do and do not respond to 4AP, to identify predictors of response. Thirty-four dogs with permanent deficits after acute thoracolumbar SCI were enrolled. Spasticity, motor and sensory evoked potentials (MEPs, SEPs), H-reflex, F-waves, gait scores, and magnetic resonance imaging (MRI) with diffusion tensor imaging (DTI) were evaluated at baseline and after 4AP administration. Baseline variables were assessed as predictors of response; response was defined as ≥1 point change in open field gait score. Variables were compared pre- and post-4AP to evaluate 4AP effects. Fifteen of 33 (45%) dogs were responders, 18/33 (55%) were non-responders and 1 was eliminated because of an adverse event. Pre-H-reflex threshold <1.2 mA predicted non-response; pre-H-reflex threshold >1.2 mA and Canine Spasticity Scale overall score <7 were predictive of response. All responders had translesional connections on DTI. MEPs were more common post-4AP than pre-4AP (10 vs. 6 dogs) and 4AP decreased H-reflex threshold and increased spasticity in responders. 4-AP impacts central conduction and motor neuron pool excitability in dogs with chronic SCI. Severity of spasticity and H-reflex threshold might allow prediction of response. Further exploration of electrodiagnostic and imaging characteristics might elucidate additional factors contributing to response or non-response.}, number={9}, journal={Journal of Neurotrauma}, publisher={Mary Ann Liebert Inc}, author={Lewis, Melissa J. and Laber, Eric and Olby, Natasha J.}, year={2019}, month={May}, pages={1428–1434} } @article{lewis_laber_olby_2019, title={Predictors of Response to 4-Aminopyridine in Chronic Canine Spinal Cord Injury}, volume={36}, ISSN={0897-7151 1557-9042}, url={http://dx.doi.org/10.1089/neu.2018.5975}, DOI={https://doi.org/10.1089/neu.2018.5975}, abstractNote={4-Aminopyridine (4AP), a potassium channel antagonist, can improve hindlimb motor function in dogs with chronic thoracolumbar spinal cord injury (SCI); however, individual response is variable. We hypothesized that injury characteristics would differ between dogs that do and do not respond to 4AP. Our objective was to compare clinical, electrodiagnostic, gait, and imaging variables between dogs that do and do not respond to 4AP, to identify predictors of response. Thirty-four dogs with permanent deficits after acute thoracolumbar SCI were enrolled. Spasticity, motor and sensory evoked potentials (MEPs, SEPs), H-reflex, F-waves, gait scores, and magnetic resonance imaging (MRI) with diffusion tensor imaging (DTI) were evaluated at baseline and after 4AP administration. Baseline variables were assessed as predictors of response; response was defined as ≥1 point change in open field gait score. Variables were compared pre- and post-4AP to evaluate 4AP effects. Fifteen of 33 (45%) dogs were responders, 18/33 (55%) were non-responders and 1 was eliminated because of an adverse event. Pre-H-reflex threshold <1.2 mA predicted non-response; pre-H-reflex threshold >1.2 mA and Canine Spasticity Scale overall score <7 were predictive of response. All responders had translesional connections on DTI. MEPs were more common post-4AP than pre-4AP (10 vs. 6 dogs) and 4AP decreased H-reflex threshold and increased spasticity in responders. 4-AP impacts central conduction and motor neuron pool excitability in dogs with chronic SCI. Severity of spasticity and H-reflex threshold might allow prediction of response. Further exploration of electrodiagnostic and imaging characteristics might elucidate additional factors contributing to response or non-response.}, number={9}, journal={Journal of Neurotrauma}, publisher={Mary Ann Liebert Inc}, author={Lewis, Melissa J. and Laber, Eric and Olby, Natasha J.}, year={2019}, month={May}, pages={1428–1434} } @article{lewis_olby_2017, title={Development of a clinical spasticity scale for evaluation of dogs with chronic thoracolumbar spinal cord injury}, volume={78}, ISSN={0002-9645}, url={http://dx.doi.org/10.2460/ajvr.78.7.854}, DOI={10.2460/ajvr.78.7.854}, abstractNote={Abstract OBJECTIVE To develop a spasticity scale for dogs with chronic deficits following severe spinal cord injury (SCI) for use in clinical assessment and outcome measurement in clinical trials. ANIMALS 20 chronically paralyzed dogs with a persistent lack of hind limb pain perception caused by an acute SCI at least 3 months previously. PROCEDURES Spasticity was assessed in both hind limbs via tests of muscle tone, clonus, and flexor and extensor spasms adapted from human scales. Measurement of patellar clonus duration and flexor spasm duration and degree was feasible. These components were used to create a canine spasticity scale (CSS; overall score range, 0 to 18). Temporal variation for individual dogs and interrater reliability were evaluated. Gait was quantified with published gait scales, and CSS scores were compared with gait scores and clinical variables. Owners were questioned regarding spasticity observed at home. RESULTS 20 dogs were enrolled: 18 with no apparent hind limb pain perception and 2 with blunted responses; 5 were ambulatory. Testing was well tolerated, and scores were repeatable between raters. Median overall CSS score was 7 (range, 3 to 11), and flexor spasms were the most prominent finding. Overall CSS score was not associated with age, SCI duration, lesion location, or owner-reported spasticity. Overall CSS score and flexor spasm duration were associated with gait scores. CONCLUSIONS AND CLINICAL RELEVANCE The CSS could be used to quantify hind limb spasticity in dogs with chronic thoracolumbar SCI and might be a useful outcome measure. Flexor spasms may represent an integral part of stepping in dogs with severe SCI.}, number={7}, journal={American Journal of Veterinary Research}, publisher={American Veterinary Medical Association (AVMA)}, author={Lewis, Melissa J. and Olby, Natasha J.}, year={2017}, month={Jul}, pages={854–861} } @article{lewis_olby_2017, title={Development of a clinical spasticity scale for evaluation of dogs with chronic thoracolumbar spinal cord injury}, volume={78}, ISSN={0002-9645}, url={http://dx.doi.org/10.2460/ajvr.78.7.854}, DOI={https://doi.org/10.2460/ajvr.78.7.854}, abstractNote={Abstract OBJECTIVE To develop a spasticity scale for dogs with chronic deficits following severe spinal cord injury (SCI) for use in clinical assessment and outcome measurement in clinical trials. ANIMALS 20 chronically paralyzed dogs with a persistent lack of hind limb pain perception caused by an acute SCI at least 3 months previously. PROCEDURES Spasticity was assessed in both hind limbs via tests of muscle tone, clonus, and flexor and extensor spasms adapted from human scales. Measurement of patellar clonus duration and flexor spasm duration and degree was feasible. These components were used to create a canine spasticity scale (CSS; overall score range, 0 to 18). Temporal variation for individual dogs and interrater reliability were evaluated. Gait was quantified with published gait scales, and CSS scores were compared with gait scores and clinical variables. Owners were questioned regarding spasticity observed at home. RESULTS 20 dogs were enrolled: 18 with no apparent hind limb pain perception and 2 with blunted responses; 5 were ambulatory. Testing was well tolerated, and scores were repeatable between raters. Median overall CSS score was 7 (range, 3 to 11), and flexor spasms were the most prominent finding. Overall CSS score was not associated with age, SCI duration, lesion location, or owner-reported spasticity. Overall CSS score and flexor spasm duration were associated with gait scores. CONCLUSIONS AND CLINICAL RELEVANCE The CSS could be used to quantify hind limb spasticity in dogs with chronic thoracolumbar SCI and might be a useful outcome measure. Flexor spasms may represent an integral part of stepping in dogs with severe SCI.}, number={7}, journal={American Journal of Veterinary Research}, publisher={American Veterinary Medical Association (AVMA)}, author={Lewis, Melissa J. and Olby, Natasha J.}, year={2017}, month={Jul}, pages={854–861} } @article{lewis_cohen_olby_2017, title={Magnetic resonance imaging features of dogs with incomplete recovery after acute, severe spinal cord injury}, volume={56}, ISSN={1362-4393 1476-5624}, url={http://dx.doi.org/10.1038/s41393-017-0004-8}, DOI={10.1038/s41393-017-0004-8}, abstractNote={{"Label"=>"STUDY DESIGN"} Retrospective case series. {"Label"=>"OBJECTIVES"} Describe the magnetic resonance imaging (MRI) features of dogs chronically impaired after severe spinal cord injury (SCI) and investigate associations between imaging variables and residual motor function. {"Label"=>"SETTING"} United States of America. {"Label"=>"METHODS"} Thoracolumbar MRI from dogs with incomplete recovery months to years after clinically complete (paralysis with loss of pain perception) thoracolumbar SCI were reviewed. Lesion features were described and quantified. Gait was quantified using an ordinal, open field scale (OFS). Associations between imaging features and gait scores, duration of injury (DOI), or SCI treatment were determined. {"Label"=>"RESULTS"} Thirty-five dogs were included. Median OFS was 2 (0-6), median DOI was 13 months (3-83), and intervertebral disk herniation was the most common diagnosis (n = 27). Myelomalacia was the most common qualitative feature followed by cystic change; syringomyelia and fibrosis were uncommon. Lesion length corrected to L2 length (LL:L2) was variable (median LL:L2 = 3.5 (1.34-11.54)). Twenty-nine dogs had 100% maximum cross-sectional spinal cord compromise (MSCC) at the lesion epicenter and the length of 100% compromised area varied widely (median length 100% MSCC:L2 = 1.29 (0.39-7.64)). Length 100% MSCC:L2 was associated with OFS (p = 0.012). OFS was not associated with any qualitative features. DOI or treatment type were not associated with imaging features or lesion quantification. {"Label"=>"CONCLUSIONS"} Lesion characteristics on MRI in dogs with incomplete recovery after severe SCI were established. Length of 100% MSCC was associated with hind limb motor function. Findings demonstrate a spectrum of injury severity on MRI among severely affected dogs, which is related to functional status.}, number={2}, journal={Spinal Cord}, publisher={Springer Science and Business Media LLC}, author={Lewis, Melissa J. and Cohen, Eli B. and Olby, Natasha J.}, year={2017}, month={Oct}, pages={133–141} } @article{lewis_cohen_olby_2017, title={Magnetic resonance imaging features of dogs with incomplete recovery after acute, severe spinal cord injury}, volume={56}, ISSN={1362-4393 1476-5624}, url={http://dx.doi.org/10.1038/s41393-017-0004-8}, DOI={https://doi.org/10.1038/s41393-017-0004-8}, number={2}, journal={Spinal Cord}, publisher={Springer Science and Business Media LLC}, author={Lewis, Melissa J. and Cohen, Eli B. and Olby, Natasha J.}, year={2017}, month={Oct}, pages={133–141} } @article{lewis_yap_mccullough_olby_2018, title={The Relationship between Lesion Severity Characterized by Diffusion Tensor Imaging and Motor Function in Chronic Canine Spinal Cord Injury}, volume={35}, ISSN={0897-7151 1557-9042}, url={http://dx.doi.org/10.1089/neu.2017.5255}, DOI={https://doi.org/10.1089/neu.2017.5255}, abstractNote={Lesion heterogeneity among chronically paralyzed dogs after acute, complete thoracolumbar spinal cord injury (TLSCI) is poorly described. We hypothesized that lesion severity quantified by diffusion tensor imaging (DTI) is associated with hindlimb motor function. Our objectives were to quantify lesion severity with fractional anisotropy (FA), mean diffusivity (MD), and tractography and investigate associations with motor function. Twenty-two dogs with complete TLSCI in the chronic stage were enrolled and compared with six control dogs. All underwent thoracolumbar magnetic resonance imaging (MRI) with DTI and gait analysis. FA and MD were calculated on regions of interest (ROI) at the lesion epicenter and cranial and caudal to the visible lesion on conventional MRI and in corresponding ROI in controls. Tractography was performed to detect translesional fibers. Gait was quantified using an ordinal scale (OFS). FA and MD values were compared between cases and controls, and relationships between FA, MD, presence of translesional fibers and OFS were investigated. The FA at the epicenter (median: 0.228, 0.107-0.320), cranial (median: 0.420, 0.391-0.561), and caudal to the lesion (median: 0.369, 0.265-0.513) was lower than combined ROI in controls (median: 0.602, 0.342-0.826, p < 0.0001). The MD at the epicenter (median: 2.06 × 10-3, 1.33-2.96 × 10-3) and cranially (median: 1.52 × 10-3, 1.03-1.87 × 10-3) was higher than combined ROI in controls (median: 1.28 × 10-3, 0.81-1.44 × 10-3, p ≤ 0.001). Four dogs had no translesional fibers. Median OFS was 2 (0-6). The FA at the lesion epicenter and presence of translesional fibers were associated with OFS (p ≤ 0.0299). DTI can detect degeneration and physical transection after severe TLSCI. Findings suggest DTI quantifies injury severity and suggests motor recovery in apparently complete dogs is because of supraspinal input.}, number={3}, journal={Journal of Neurotrauma}, publisher={Mary Ann Liebert Inc}, author={Lewis, Melissa J. and Yap, Pew-Thian and McCullough, Susan and Olby, Natasha J.}, year={2018}, month={Feb}, pages={500–507} } @article{lewis_yap_mccullough_olby_2018, title={The Relationship between Lesion Severity Characterized by Diffusion Tensor Imaging and Motor Function in Chronic Canine Spinal Cord Injury}, volume={35}, ISSN={0897-7151 1557-9042}, url={http://dx.doi.org/10.1089/neu.2017.5255}, DOI={10.1089/neu.2017.5255}, abstractNote={Lesion heterogeneity among chronically paralyzed dogs after acute, complete thoracolumbar spinal cord injury (TLSCI) is poorly described. We hypothesized that lesion severity quantified by diffusion tensor imaging (DTI) is associated with hindlimb motor function. Our objectives were to quantify lesion severity with fractional anisotropy (FA), mean diffusivity (MD), and tractography and investigate associations with motor function. Twenty-two dogs with complete TLSCI in the chronic stage were enrolled and compared with six control dogs. All underwent thoracolumbar magnetic resonance imaging (MRI) with DTI and gait analysis. FA and MD were calculated on regions of interest (ROI) at the lesion epicenter and cranial and caudal to the visible lesion on conventional MRI and in corresponding ROI in controls. Tractography was performed to detect translesional fibers. Gait was quantified using an ordinal scale (OFS). FA and MD values were compared between cases and controls, and relationships between FA, MD, presence of translesional fibers and OFS were investigated. The FA at the epicenter (median: 0.228, 0.107-0.320), cranial (median: 0.420, 0.391-0.561), and caudal to the lesion (median: 0.369, 0.265-0.513) was lower than combined ROI in controls (median: 0.602, 0.342-0.826, p < 0.0001). The MD at the epicenter (median: 2.06 × 10-3, 1.33-2.96 × 10-3) and cranially (median: 1.52 × 10-3, 1.03-1.87 × 10-3) was higher than combined ROI in controls (median: 1.28 × 10-3, 0.81-1.44 × 10-3, p ≤ 0.001). Four dogs had no translesional fibers. Median OFS was 2 (0-6). The FA at the lesion epicenter and presence of translesional fibers were associated with OFS (p ≤ 0.0299). DTI can detect degeneration and physical transection after severe TLSCI. Findings suggest DTI quantifies injury severity and suggests motor recovery in apparently complete dogs is because of supraspinal input.}, number={3}, journal={Journal of Neurotrauma}, publisher={Mary Ann Liebert Inc}, author={Lewis, Melissa J. and Yap, Pew-Thian and McCullough, Susan and Olby, Natasha J.}, year={2018}, month={Feb}, pages={500–507} } @article{lewis_howard_olby_2017, title={The Relationship between Trans-Lesional Conduction, Motor Neuron Pool Excitability, and Motor Function in Dogs with Incomplete Recovery from Severe Spinal Cord Injury}, volume={34}, ISSN={0897-7151 1557-9042}, url={http://dx.doi.org/10.1089/neu.2017.5012}, DOI={10.1089/neu.2017.5012}, abstractNote={Spontaneous, acute, complete thoracolumbar spinal cord injury (TL-SCI) in dogs frequently results in permanent deficits modeling chronic paralysis in people. Recovery of walking without recovery of sensation has been interpreted in dogs as reflexive spinal walking. To evaluate this assumption, this study characterized the electrophysiological status of motor and sensory long tracts and local reflex circuitry in dogs with absent recovery of sensation after acute TL-SCI and correlated findings to gait scores. Twenty dogs with permanent deficits after acute, clinically complete TL-SCI and 6 normal dogs were prospectively enrolled. Transcranial magnetic motor evoked potentials (MEPs), somatosensory evoked potentials (SSEPs), H-reflex, and F-waves were evaluated. Gait was quantified using an ordinal, open field scale (OFS) and treadmill-based stepping and coordination scores (SS, RI). MEP latency and H-reflex variables were compared between cases and controls. Associations between presence of MEPs, SSEPs, F-waves or H-reflex variables, and gait scores were determined. Pelvic limb MEPs were detected in 4 cases; no case had trans-lesional sensory conduction. Latency was longer and conduction velocity slower in cases than controls (pa = 0.0064, 0.0023, respectively). Three of 4 cases with pelvic limb MEPs were ambulatory, and gait scores (OFS, SS, RI) were each associated with presence of trans-lesional conduction (pa = 0.006, 0.006, 0.003, respectively). H threshold in cases (mean, 3.2mA ±2.5) was lower than controls (mean, 7.9mA ±3.1; pa = 0.011) and was inversely associated with treadmill-based scores, SS, and RI (pa = 0.042, 0.043, respectively). The association between pelvic limb MEPs and gait scores supports the importance of descending influence on regaining walking after severe TL-SCI in dogs rather than just activation of spinal walking. The inverse association between H-reflex threshold and gait scores implies that increases in motor neuron pool excitability might also contribute to motor recovery.}, number={21}, journal={Journal of Neurotrauma}, publisher={Mary Ann Liebert Inc}, author={Lewis, Melissa J. and Howard, James F., Jr and Olby, Natasha J.}, year={2017}, month={Nov}, pages={2994–3002} } @article{lewis_howard_olby_2017, title={The Relationship between Trans-Lesional Conduction, Motor Neuron Pool Excitability, and Motor Function in Dogs with Incomplete Recovery from Severe Spinal Cord Injury}, volume={34}, ISSN={0897-7151 1557-9042}, url={http://dx.doi.org/10.1089/neu.2017.5012}, DOI={https://doi.org/10.1089/neu.2017.5012}, abstractNote={Spontaneous, acute, complete thoracolumbar spinal cord injury (TL-SCI) in dogs frequently results in permanent deficits modeling chronic paralysis in people. Recovery of walking without recovery of sensation has been interpreted in dogs as reflexive spinal walking. To evaluate this assumption, this study characterized the electrophysiological status of motor and sensory long tracts and local reflex circuitry in dogs with absent recovery of sensation after acute TL-SCI and correlated findings to gait scores. Twenty dogs with permanent deficits after acute, clinically complete TL-SCI and 6 normal dogs were prospectively enrolled. Transcranial magnetic motor evoked potentials (MEPs), somatosensory evoked potentials (SSEPs), H-reflex, and F-waves were evaluated. Gait was quantified using an ordinal, open field scale (OFS) and treadmill-based stepping and coordination scores (SS, RI). MEP latency and H-reflex variables were compared between cases and controls. Associations between presence of MEPs, SSEPs, F-waves or H-reflex variables, and gait scores were determined. Pelvic limb MEPs were detected in 4 cases; no case had trans-lesional sensory conduction. Latency was longer and conduction velocity slower in cases than controls (pa = 0.0064, 0.0023, respectively). Three of 4 cases with pelvic limb MEPs were ambulatory, and gait scores (OFS, SS, RI) were each associated with presence of trans-lesional conduction (pa = 0.006, 0.006, 0.003, respectively). H threshold in cases (mean, 3.2mA ±2.5) was lower than controls (mean, 7.9mA ±3.1; pa = 0.011) and was inversely associated with treadmill-based scores, SS, and RI (pa = 0.042, 0.043, respectively). The association between pelvic limb MEPs and gait scores supports the importance of descending influence on regaining walking after severe TL-SCI in dogs rather than just activation of spinal walking. The inverse association between H-reflex threshold and gait scores implies that increases in motor neuron pool excitability might also contribute to motor recovery.}, number={21}, journal={Journal of Neurotrauma}, publisher={Mary Ann Liebert Inc}, author={Lewis, Melissa J. and Howard, James F., Jr and Olby, Natasha J.}, year={2017}, month={Nov}, pages={2994–3002} } @article{lewis_olby_early_mariani_muñana_seiler_griffith_2016, title={Clinical and Diagnostic Imaging Features of Brain Herniation in Dogs and Cats}, volume={30}, ISSN={0891-6640 1939-1676}, url={http://dx.doi.org/10.1111/jvim.14526}, DOI={10.1111/jvim.14526}, abstractNote={BackgroundQuantification of brain herniation on MRI and its immediate clinical implications are poorly described.ObjectivesDefine the normal position of caudal fossa structures on brain MRIs in dogs and cats utilizing morphometry, compare this to dogs and cats with caudal transtentorial herniation (CTH), foramen magnum herniation (FMH) or both identified on MRI, and investigate associations between herniation severity, clinical signs, and 24‐hour outcome.AnimalsNinety‐two controls (66 dogs, 26 cats), 119 cases with herniation (88 dogs, 31 cats).MethodsRetrospective case series. The MRI database was searched for controls with normal brain anatomy and cases with brain herniation. Morphometry in controls established TTX (transtentorial to rostroventral cerebellum) to quantify CTH and FMX (caudoventral cerebellum to foramen magnum) to quantify FMH. Measurements were compared between cases and controls. Correlations with specific clinical variables and outcome were investigated.ResultsMeasurements in medium/large control dogs versus small dog and cat controls were significantly different (P < .001, TTX: −0.46, −0.305, −0.3, FMX: 0.695, 0.27, 0.25, respectively). 119/1564 (7.6%) cases that underwent brain imaging had brain herniation. TTX and FMX were significantly different between controls and cases with CTH or FMH (P < .001). 67/89 (75%) cases with supratentorial lesions had no signs directly attributable to herniation. 71/119 (60%) had a normal anesthetic recovery. TTX was significantly associated with 24‐hour survival (P < .001).Conclusions and clinical importanceBrain herniation can be quantified on MRI. Clinical signs directly attributable to brain herniation commonly are absent, and more severe CTH based on TTX is associated with a worse short‐term outcome.}, number={5}, journal={Journal of Veterinary Internal Medicine}, publisher={Wiley}, author={Lewis, M.J. and Olby, N.J. and Early, P.J. and Mariani, C.L. and Muñana, K.R. and Seiler, G.S. and Griffith, E.H.}, year={2016}, month={Sep}, pages={1672–1680} } @article{lewis_olby_early_mariani_muñana_seiler_griffith_2016, title={Clinical and Diagnostic Imaging Features of Brain Herniation in Dogs and Cats}, volume={30}, ISSN={0891-6640 1939-1676}, url={http://dx.doi.org/10.1111/jvim.14526}, DOI={https://doi.org/10.1111/jvim.14526}, abstractNote={Quantification of brain herniation on MRI and its immediate clinical implications are poorly described.Define the normal position of caudal fossa structures on brain MRIs in dogs and cats utilizing morphometry, compare this to dogs and cats with caudal transtentorial herniation (CTH), foramen magnum herniation (FMH) or both identified on MRI, and investigate associations between herniation severity, clinical signs, and 24-hour outcome.Ninety-two controls (66 dogs, 26 cats), 119 cases with herniation (88 dogs, 31 cats).Retrospective case series. The MRI database was searched for controls with normal brain anatomy and cases with brain herniation. Morphometry in controls established TTX (transtentorial to rostroventral cerebellum) to quantify CTH and FMX (caudoventral cerebellum to foramen magnum) to quantify FMH. Measurements were compared between cases and controls. Correlations with specific clinical variables and outcome were investigated.Measurements in medium/large control dogs versus small dog and cat controls were significantly different (P < .001, TTX: -0.46, -0.305, -0.3, FMX: 0.695, 0.27, 0.25, respectively). 119/1564 (7.6%) cases that underwent brain imaging had brain herniation. TTX and FMX were significantly different between controls and cases with CTH or FMH (P < .001). 67/89 (75%) cases with supratentorial lesions had no signs directly attributable to herniation. 71/119 (60%) had a normal anesthetic recovery. TTX was significantly associated with 24-hour survival (P < .001).Brain herniation can be quantified on MRI. Clinical signs directly attributable to brain herniation commonly are absent, and more severe CTH based on TTX is associated with a worse short-term outcome.}, number={5}, journal={Journal of Veterinary Internal Medicine}, publisher={Wiley}, author={Lewis, M.J. and Olby, N.J. and Early, P.J. and Mariani, C.L. and Muñana, K.R. and Seiler, G.S. and Griffith, E.H.}, year={2016}, month={Sep}, pages={1672–1680} } @article{oura_early_jennings_lewis_tobias_thrall_2013, title={Canine Choroid Plexus Tumor with Intracranial Dissemination Presenting as Multiple Cystic Lesions}, volume={2013}, ISSN={2090-7001 2090-701X}, url={http://dx.doi.org/10.1155/2013/759054}, DOI={10.1155/2013/759054}, abstractNote={A Miniature Pinscher developed acute blindness and behavioral changes. On magnetic resonance imaging (MRI), there were multiple small intra-axial cystic lesions, and primary differential diagnoses included primary or metastatic neoplasia and neurocysticercosis. These cystic lesions were subsequently diagnosed histopathologically as disseminated choroid plexus carcinoma. This is only the second documented description of this diagnosis in a dog, but both patients had very similar MRI findings. This patient adds to the literature about the MRI characteristics of choroid plexus tumors and indicates that choroid plexus tumor should be considered as a possible cause of small multifocal intra-axial cystic brain lesions in dogs, regardless of whether a primary intraventricular lesion is visible.}, journal={Case Reports in Veterinary Medicine}, publisher={Hindawi Limited}, author={Oura, Trisha J. and Early, Peter J. and Jennings, Samuel H. and Lewis, Melissa J. and Tobias, Jeremy R. and Thrall, Donald E.}, year={2013}, pages={1–4} } @article{lewis_olby_sharp_early_2013, title={Long‐Term Effect of Cervical Distraction and Stabilization on Neurological Status and Imaging Findings in Giant Breed Dogs With Cervical Stenotic Myelopathy}, volume={42}, ISSN={0161-3499 1532-950X}, url={http://dx.doi.org/10.1111/j.1532-950X.2013.12034.x}, DOI={10.1111/j.1532-950x.2013.12034.x}, abstractNote={AbstractObjectivesTo assess long‐term clinical and imaging outcomes in giant breed dogs with cervical stenotic myelopathy treated surgically.Study DesignRetrospective case series.AnimalsDogs (n = 7).MethodsAll dogs had lateral or dorsolateral cord compression at 1 or more sites and were treated with cervical distraction and stabilization using PMMA plugs. Four dogs had follow‐up CT or CT/myelography performed at least 6 months postoperatively. Spinal canal stenosis measurements were compared between pre‐ and postoperative CT images. Long‐term clinical neurologic re‐evaluation ranged from 4 to 7 years. Outcome was considered positive, satisfactory, or negative. Recurrence was defined as signs of a cervical myelopathy in dogs that initially improved or had stable disease postoperatively.ResultsAll dogs had immediate postoperative improvement. Recurrence (4 months to 4 years postoperatively) occurred in 3 dogs that had multiple sites of compression. Long‐term outcome was positive in 4 of 7 dogs. Postoperative imaging revealed subjective regression of bony proliferation at surgical sites in 2 of 4 dogs that improved clinically but morphometric data showed no change in canal measurements. An adjacent site lesion was confirmed in 1 dog.ConclusionsDistraction and stabilization with PMMA plugs and bone grafts is a safe surgical option for giant breed dogs with CSM with a single site of lateral or dorsolateral compression. Long‐term recurrence was common among dogs with multiple sites of compression. Follow‐up of 4 years or more among a larger population is indicated to fully assess implications of surgical intervention and determine recurrence rates.}, number={6}, journal={Veterinary Surgery}, publisher={Wiley}, author={Lewis, Melissa and Olby, Natasha J and Sharp, Nick JH. and Early, Peter}, year={2013}, month={Jul}, pages={701–709} } @article{lewis_olby_sharp_early_2013, title={Long‐Term Effect of Cervical Distraction and Stabilization on Neurological Status and Imaging Findings in Giant Breed Dogs With Cervical Stenotic Myelopathy}, volume={42}, ISSN={0161-3499 1532-950X}, url={http://dx.doi.org/10.1111/j.1532-950x.2013.12034.x}, DOI={https://doi.org/10.1111/j.1532-950x.2013.12034.x}, abstractNote={Abstract Objectives To assess long‐term clinical and imaging outcomes in giant breed dogs with cervical stenotic myelopathy treated surgically. Study Design Retrospective case series. Animals Dogs (n = 7). Methods All dogs had lateral or dorsolateral cord compression at 1 or more sites and were treated with cervical distraction and stabilization using PMMA plugs. Four dogs had follow‐up CT or CT/myelography performed at least 6 months postoperatively. Spinal canal stenosis measurements were compared between pre‐ and postoperative CT images. Long‐term clinical neurologic re‐evaluation ranged from 4 to 7 years. Outcome was considered positive, satisfactory, or negative. Recurrence was defined as signs of a cervical myelopathy in dogs that initially improved or had stable disease postoperatively. Results All dogs had immediate postoperative improvement. Recurrence (4 months to 4 years postoperatively) occurred in 3 dogs that had multiple sites of compression. Long‐term outcome was positive in 4 of 7 dogs. Postoperative imaging revealed subjective regression of bony proliferation at surgical sites in 2 of 4 dogs that improved clinically but morphometric data showed no change in canal measurements. An adjacent site lesion was confirmed in 1 dog. Conclusions Distraction and stabilization with PMMA plugs and bone grafts is a safe surgical option for giant breed dogs with CSM with a single site of lateral or dorsolateral compression. Long‐term recurrence was common among dogs with multiple sites of compression. Follow‐up of 4 years or more among a larger population is indicated to fully assess implications of surgical intervention and determine recurrence rates.}, number={6}, journal={Veterinary Surgery}, publisher={Wiley}, author={Lewis, Melissa and Olby, Natasha J and Sharp, Nick JH. and Early, Peter}, year={2013}, month={Jul}, pages={701–709} } @article{malik_lewis_isaacs_haskins_van winkle_vite_watson_2012, title={Identification of the Rostral Migratory Stream in the Canine and Feline Brain}, volume={7}, ISSN={1932-6203}, url={http://dx.doi.org/10.1371/journal.pone.0036016}, DOI={10.1371/journal.pone.0036016}, abstractNote={In the adult rodent brain, neural progenitor cells migrate from the subventricular zone of the lateral ventricle towards the olfactory bulb in a track known as the rostral migratory stream (RMS). To facilitate the study of neural progenitor cells and stem cell therapy in large animal models of CNS disease, we now report the location and characteristics of the normal canine and feline RMS. The RMS was found in Nissl-stained sagittal sections of adult canine and feline brains as a prominent, dense, continuous cellular track beginning at the base of the anterior horn of the lateral ventricle, curving around the head of the caudate nucleus and continuing laterally and ventrally to the olfactory peduncle before entering the olfactory tract and bulb. To determine if cells in the RMS were proliferating, the thymidine analog 5-bromo-2-deoxyuridine (BrdU) was administered and detected by immunostaining. BrdU-immunoreactive cells were present throughout this track. The RMS was also immunoreactive for markers of proliferating cells, progenitor cells and immature neurons (Ki-67 and doublecortin), but not for NeuN, a marker of mature neurons. Luxol fast blue and CNPase staining indicated that myelin is closely apposed to the RMS along much of its length and may provide guidance cues for the migrating cells. Identification and characterization of the RMS in canine and feline brain will facilitate studies of neural progenitor cell biology and migration in large animal models of neurologic disease.}, number={5}, journal={PLoS ONE}, publisher={Public Library of Science (PLoS)}, author={Malik, Saafan Z. and Lewis, Melissa and Isaacs, Alison and Haskins, Mark and Van Winkle, Thomas and Vite, Charles H. and Watson, Deborah J.}, editor={Androutsellis-Theotokis, AndreasEditor}, year={2012}, month={May}, pages={e36016} } @article{malik_lewis_isaacs_haskins_van winkle_vite_watson_2012, title={Identification of the Rostral Migratory Stream in the Canine and Feline Brain}, volume={7}, ISSN={1932-6203}, url={http://dx.doi.org/10.1371/journal.pone.0036016}, DOI={https://doi.org/10.1371/journal.pone.0036016}, abstractNote={In the adult rodent brain, neural progenitor cells migrate from the subventricular zone of the lateral ventricle towards the olfactory bulb in a track known as the rostral migratory stream (RMS). To facilitate the study of neural progenitor cells and stem cell therapy in large animal models of CNS disease, we now report the location and characteristics of the normal canine and feline RMS. The RMS was found in Nissl-stained sagittal sections of adult canine and feline brains as a prominent, dense, continuous cellular track beginning at the base of the anterior horn of the lateral ventricle, curving around the head of the caudate nucleus and continuing laterally and ventrally to the olfactory peduncle before entering the olfactory tract and bulb. To determine if cells in the RMS were proliferating, the thymidine analog 5-bromo-2-deoxyuridine (BrdU) was administered and detected by immunostaining. BrdU-immunoreactive cells were present throughout this track. The RMS was also immunoreactive for markers of proliferating cells, progenitor cells and immature neurons (Ki-67 and doublecortin), but not for NeuN, a marker of mature neurons. Luxol fast blue and CNPase staining indicated that myelin is closely apposed to the RMS along much of its length and may provide guidance cues for the migrating cells. Identification and characterization of the RMS in canine and feline brain will facilitate studies of neural progenitor cell biology and migration in large animal models of neurologic disease.}, number={5}, journal={PLoS ONE}, publisher={Public Library of Science (PLoS)}, author={Malik, Saafan Z. and Lewis, Melissa and Isaacs, Alison and Haskins, Mark and Van Winkle, Thomas and Vite, Charles H. and Watson, Deborah J.}, editor={Androutsellis-Theotokis, AndreasEditor}, year={2012}, month={May}, pages={e36016} } @article{lewis_williams_vite_2011, title={Evaluation of the electroencephalogram in young cats}, volume={72}, ISSN={0002-9645}, url={http://dx.doi.org/10.2460/ajvr.72.3.391}, DOI={10.2460/ajvr.72.3.391}, abstractNote={Abstract Objective —To characterize the electroencephalogram (EEG) in young cats. Animals —23 clinically normal cats. Procedures —Cats were sedated with medetomidine hydrochloride and butorphanol tartrate at 2, 4, 6, 8, 12, 16, 20, and 24 weeks of age, and an EEG was recorded at each time point. Recordings were visually inspected for electrical continuity, interhemispheric synchrony, amplitude and frequency of background electrical activity, and frequency of transient activity. Computer-aided analysis was used to perform frequency spectral analysis and to calculate absolute and relative power of the background activity at each age. Results —Electrical continuity was evident in cats ≥ 4 weeks old, and interhemispheric synchrony was evident in cats at all ages evaluated. Analysis of amplitude of background activity and absolute power revealed significant elevations in 6-week-old cats, compared with results for 2-, 20-, and 24-week-old cats. No association between age and relative power or frequency was identified. Transient activity, which consisted of sleep spindles and K complexes, was evident at all ages, but spike and spike-and-wave discharges were observed in cats at 2 weeks of age. Conclusions and Clinical Relevance —Medetomidine and butorphanol were administered in accordance with a sedation protocol that allowed investigators to repeatedly obtain EEG data from cats. Age was an important consideration when interpreting EEG data. These data on EEG development in clinically normal cats may be used for comparison in future studies conducted to examine EEGs in young cats with diseases that affect the cerebral cortex.}, number={3}, journal={American Journal of Veterinary Research}, publisher={American Veterinary Medical Association (AVMA)}, author={Lewis, Melissa J. and Williams, D. Colette and Vite, Charles H.}, year={2011}, month={Mar}, pages={391–397} } @article{lewis_williams_vite_2011, title={Evaluation of the electroencephalogram in young cats}, volume={72}, ISSN={0002-9645}, url={http://dx.doi.org/10.2460/ajvr.72.3.391}, DOI={https://doi.org/10.2460/ajvr.72.3.391}, abstractNote={Abstract Objective —To characterize the electroencephalogram (EEG) in young cats. Animals —23 clinically normal cats. Procedures —Cats were sedated with medetomidine hydrochloride and butorphanol tartrate at 2, 4, 6, 8, 12, 16, 20, and 24 weeks of age, and an EEG was recorded at each time point. Recordings were visually inspected for electrical continuity, interhemispheric synchrony, amplitude and frequency of background electrical activity, and frequency of transient activity. Computer-aided analysis was used to perform frequency spectral analysis and to calculate absolute and relative power of the background activity at each age. Results —Electrical continuity was evident in cats ≥ 4 weeks old, and interhemispheric synchrony was evident in cats at all ages evaluated. Analysis of amplitude of background activity and absolute power revealed significant elevations in 6-week-old cats, compared with results for 2-, 20-, and 24-week-old cats. No association between age and relative power or frequency was identified. Transient activity, which consisted of sleep spindles and K complexes, was evident at all ages, but spike and spike-and-wave discharges were observed in cats at 2 weeks of age. Conclusions and Clinical Relevance —Medetomidine and butorphanol were administered in accordance with a sedation protocol that allowed investigators to repeatedly obtain EEG data from cats. Age was an important consideration when interpreting EEG data. These data on EEG development in clinically normal cats may be used for comparison in future studies conducted to examine EEGs in young cats with diseases that affect the cerebral cortex.}, number={3}, journal={American Journal of Veterinary Research}, publisher={American Veterinary Medical Association (AVMA)}, author={Lewis, Melissa J. and Williams, D. Colette and Vite, Charles H.}, year={2011}, month={Mar}, pages={391–397} } @article{gordon_cheung_levin_andrews_doorish_macarthur_montes_bednarz_florence_rowin_et al._2008, title={A novel, efficient, randomized selection trial comparing combinations of drug therapy for ALS}, volume={9}, ISSN={1748-2968 1471-180X}, url={http://dx.doi.org/10.1080/17482960802195632}, DOI={https://doi.org/10.1080/17482960802195632}, abstractNote={Combining agents with different mechanisms of action may be necessary for meaningful results in treating ALS. The combinations of minocycline-creatine and celecoxib-creatine have additive effects in the murine model. New trial designs are needed to efficiently screen the growing number of potential neuroprotective agents. Our objective was to assess two drug combinations in ALS using a novel phase II trial design. We conducted a randomized, double-blind selection trial in sequential pools of 60 patients. Participants received minocycline (100 mg)-creatine (10 g) twice daily or celecoxib (400 mg)-creatine (10 g) twice daily for six months. The primary objective was treatment selection based on which combination best slowed deterioration in the ALS Functional Rating Scale-Revised (ALSFRS-R); the trial could be stopped after one pool if the difference between the two arms was adequately large. At trial conclusion, each arm was compared to a historical control group in a futility analysis. Safety measures were also examined. After the first patient pool, the mean six-month decline in ALSFRS-R was 5.27 (SD=5.54) in the celecoxib-creatine group and 6.47 (SD=9.14) in the minocycline-creatine group. The corresponding decline was 5.82 (SD=6.77) in the historical controls. The difference between the two sample means exceeded the stopping criterion. The null hypothesis of superiority was not rejected in the futility analysis. Skin rash occurred more frequently in the celecoxib-creatine group. In conclusion, the celecoxib-creatine combination was selected as preferable to the minocycline-creatine combination for further evaluation. This phase II design was efficient, leading to treatment selection after just 60 patients, and can be used in other phase II trials to assess different agents.}, number={4}, journal={Amyotrophic Lateral Sclerosis}, publisher={Informa UK Limited}, author={Gordon, Paul H. and Cheung, Ying-Kuen and Levin, Bruce and Andrews, Howard and Doorish, Carolyn and Macarthur, Robert B. and Montes, Jacqueline and Bednarz, Kate and Florence, Julaine and Rowin, Julie and et al.}, year={2008}, month={Jan}, pages={212–222} } @article{gordon_wang_doorish_lewis_battista_mitsumoto_marder_2007, title={A screening assessment of cognitive impairment in patients with ALS}, volume={8}, ISSN={1748-2968 1471-180X}, url={http://dx.doi.org/10.1080/17482960701500817}, DOI={10.1080/17482960701500817}, abstractNote={We wished to determine whether a screening test battery for cognitive impairment can be given practicably in a busy multidisciplinary ALS clinic, and to assess initial test performance in a sequentially drawn ALS population. We administered a word generation task (letter fluency), the Frontal Behavioral Inventory (FBI), and the Beck Depression Inventory (BDI) to 49 ALS patients and their caregivers during a visit to our ALS clinic. We also computed Clinical Dementia Rating (CDR) scale and ALS Functional Rating Scale (ALSFRS‐R) scores for patients. Pearson correlation coefficients and regression analyses assessed associations between outcome measures. The test battery took 30 min to administer. Word generation was associated with the FBI score (r = −0.36, p = 0.01), and time to ALS diagnosis (p = 0.01). Caregiver depressive symptoms (BDI) correlated with the FBI (r = 0.40, p = 0.005) and motor severity (r = −0.47, p<0.01) in patients. CDR scores were associated with behavioral abnormalities and lower ALSFRS‐R scores. We concluded that a screen of cognition could be administered during multidisciplinary ALS clinics. Frontostriatal cognitive impairment may be associated with behavioral syndromes and more rapid forms of ALS. Behavioral and motor impairment is associated with depressive symptoms in caregivers. Studies with formal neuropsychological tests are needed to determine the sensitivity and specificity of the screen in ALS.}, number={6}, journal={Amyotrophic Lateral Sclerosis}, publisher={Informa UK Limited}, author={Gordon, Paul H. and Wang, Yuanjia and Doorish, Carolyn and Lewis, Melissa and Battista, Vanessa and Mitsumoto, Hiroshi and Marder, Karen}, year={2007}, month={Jan}, pages={362–365} } @article{gordon_wang_doorish_lewis_battista_mitsumoto_marder_2007, title={A screening assessment of cognitive impairment in patients with ALS}, volume={8}, ISSN={1748-2968 1471-180X}, url={http://dx.doi.org/10.1080/17482960701500817}, DOI={https://doi.org/10.1080/17482960701500817}, abstractNote={We wished to determine whether a screening test battery for cognitive impairment can be given practicably in a busy multidisciplinary ALS clinic, and to assess initial test performance in a sequentially drawn ALS population. We administered a word generation task (letter fluency), the Frontal Behavioral Inventory (FBI), and the Beck Depression Inventory (BDI) to 49 ALS patients and their caregivers during a visit to our ALS clinic. We also computed Clinical Dementia Rating (CDR) scale and ALS Functional Rating Scale (ALSFRS‐R) scores for patients. Pearson correlation coefficients and regression analyses assessed associations between outcome measures. The test battery took 30 min to administer. Word generation was associated with the FBI score (r = −0.36, p = 0.01), and time to ALS diagnosis (p = 0.01). Caregiver depressive symptoms (BDI) correlated with the FBI (r = 0.40, p = 0.005) and motor severity (r = −0.47, p<0.01) in patients. CDR scores were associated with behavioral abnormalities and lower ALSFRS‐R scores. We concluded that a screen of cognition could be administered during multidisciplinary ALS clinics. Frontostriatal cognitive impairment may be associated with behavioral syndromes and more rapid forms of ALS. Behavioral and motor impairment is associated with depressive symptoms in caregivers. Studies with formal neuropsychological tests are needed to determine the sensitivity and specificity of the screen in ALS.}, number={6}, journal={Amyotrophic Lateral Sclerosis}, publisher={Informa UK Limited}, author={Gordon, Paul H. and Wang, Yuanjia and Doorish, Carolyn and Lewis, Melissa and Battista, Vanessa and Mitsumoto, Hiroshi and Marder, Karen}, year={2007}, month={Jan}, pages={362–365} } @article{lewis_gordon_2007, title={Lou Gehrig, Rawhide, and 1938}, volume={68}, ISSN={0028-3878 1526-632X}, url={http://dx.doi.org/10.1212/01.wnl.0000254623.04219.aa}, DOI={10.1212/01.wnl.0000254623.04219.aa}, abstractNote={Lou Gehrig was one of the most talented baseball players of all time; yet he is also remembered for ALS, the disease that took his life and still bears his name as its eponym. There is speculation about when his symptoms began. Some authorities believe that Gehrig showed signs of ALS when he starred in the film Rawhide in January 1938, which would mean that he played the entire 1938 season with symptomatic ALS. Additionally, some photographs of Gehrig showing atrophy of hand muscles have been dated incorrectly because of misinterpreted logos on his uniform. We examined the film and photos taken of Gehrig from 1937 to 1939 to determine whether he showed signs of weakness in the film and when visible evidence of ALS could be documented. Specific scenes from Rawhide were chosen to grade Gehrig's motor function using the ALS Functional Rating Scale (ALSFRS). Dates of photos and uniform logos were verified with the Baseball Hall of Fame. Examination of Rawhide showed that Gehrig functioned normally in January 1938. His ALSFRS score, modified to account for limitations of on-screen activities, was normal. The New York Yankees wore logos in 1938 that were labeled with the year 1939 to advertise the 1939 World's Fair; the uniforms displayed a centennial patch during the 1939 season. A photograph of Gehrig from October 1939 showed hand atrophy. Photos from the spring of 1938 showed normal hand muscles and leg function, implying that visible signs first appeared after May 1938.}, number={8}, journal={Neurology}, publisher={Ovid Technologies (Wolters Kluwer Health)}, author={Lewis, Melissa and Gordon, Paul H.}, year={2007}, month={Feb}, pages={615–618} } @article{lewis_gordon_2007, title={Lou Gehrig, Rawhide, and 1938}, volume={68}, ISSN={0028-3878 1526-632X}, url={http://dx.doi.org/10.1212/01.wnl.0000254623.04219.aa}, DOI={https://doi.org/10.1212/01.wnl.0000254623.04219.aa}, abstractNote={Lou Gehrig was one of the most talented baseball players of all time; yet he is also remembered for ALS, the disease that took his life and still bears his name as its eponym. There is speculation about when his symptoms began. Some authorities believe that Gehrig showed signs of ALS when he starred in the film Rawhide in January 1938, which would mean that he played the entire 1938 season with symptomatic ALS. Additionally, some photographs of Gehrig showing atrophy of hand muscles have been dated incorrectly because of misinterpreted logos on his uniform. We examined the film and photos taken of Gehrig from 1937 to 1939 to determine whether he showed signs of weakness in the film and when visible evidence of ALS could be documented. Specific scenes from Rawhide were chosen to grade Gehrig's motor function using the ALS Functional Rating Scale (ALSFRS). Dates of photos and uniform logos were verified with the Baseball Hall of Fame. Examination of Rawhide showed that Gehrig functioned normally in January 1938. His ALSFRS score, modified to account for limitations of on-screen activities, was normal. The New York Yankees wore logos in 1938 that were labeled with the year 1939 to advertise the 1939 World's Fair; the uniforms displayed a centennial patch during the 1939 season. A photograph of Gehrig from October 1939 showed hand atrophy. Photos from the spring of 1938 showed normal hand muscles and leg function, implying that visible signs first appeared after May 1938.}, number={8}, journal={Neurology}, publisher={Ovid Technologies (Wolters Kluwer Health)}, author={Lewis, Melissa and Gordon, Paul H.}, year={2007}, month={Feb}, pages={615–618} }