@article{woelfel_mariani_nolan_keenihan_topulos_early_munana_musulin_olby_2023, title={Presumed pituitary apoplexy in 26 dogs: Clinical findings, treatments, and outcomes}, volume={4}, ISSN={["1939-1676"]}, url={https://doi.org/10.1111/jvim.16703}, DOI={10.1111/jvim.16703}, abstractNote={AbstractBackgroundPituitary apoplexy refers to hemorrhage or infarction within the pituitary gland resulting in acute neurological abnormalities. This condition is poorly described in dogs.ObjectivesTo document presenting complaints, examination findings, endocrinopathies, magnetic resonance imaging (MRI), treatments, and outcomes of dogs with pituitary apoplexy.AnimalsTwenty‐six client‐owned dogs with acute onset of neurological dysfunction.MethodsRetrospective case series. Dogs were diagnosed with pituitary apoplexy if MRI or histopathology documented an intrasellar or suprasellar mass with evidence of hemorrhage or infarction in conjunction with acute neurological dysfunction. Clinical information was obtained from medical records and imaging reports.ResultsCommon presenting complaints included altered mentation (16/26, 62%) and gastrointestinal dysfunction (14/26, 54%). Gait or posture changes (22/26, 85%), mentation changes (18/26, 69%), cranial neuropathies (17/26, 65%), cervical or head hyperpathia (12/26, 46%), and hyperthermia (8/26, 31%) were the most frequent exam findings. Ten dogs (38%) lacked evidence of an endocrinopathy before presentation. Common MRI findings included T1‐weighted hypo‐ to isointensity of the hemorrhagic lesion (21/25, 84%), peripheral enhancement of the pituitary mass lesion (15/25, 60%), brain herniation (14/25, 56%), and obstructive hydrocephalus (13/25, 52%). Fifteen dogs (58%) survived to hospital discharge. Seven of these dogs received medical management alone (median survival 143 days; range, 7‐641 days) and 8 received medications and radiation therapy (median survival 973 days; range, 41‐1719 days).Conclusions and Clinical ImportanceDogs with pituitary apoplexy present with a variety of acute signs of neurological disease and inconsistent endocrine dysfunction. Dogs that survive to discharge can have a favorable outcome.}, journal={JOURNAL OF VETERINARY INTERNAL MEDICINE}, author={Woelfel, Christian W. and Mariani, Christopher L. and Nolan, Michael W. and Keenihan, Erin K. and Topulos, Sophia P. and Early, Peter J. and Munana, Karen R. and Musulin, Sarah E. and Olby, Natasha J.}, year={2023}, month={Apr} }
 @article{woelfel_meurs_friedenberg_debruyne_olby_2022, title={A novel mutation of the CLCN1 gene in a cat with myotonia congenita: Diagnosis and treatment}, volume={7}, ISSN={["1939-1676"]}, url={https://doi.org/10.1111/jvim.16471}, DOI={10.1111/jvim.16471}, abstractNote={AbstractCase DescriptionA 10‐month‐old castrated male domestic longhair cat was evaluated for increasing frequency of episodic limb rigidity.Clinical FindingsThe cat presented for falling over and lying recumbent with its limbs in extension for several seconds when startled or excited. Upon examination, the cat had hypertrophied musculature, episodes of facial spasm, and a short‐strided, stiff gait.DiagnosticsElectromyography (EMG) identified spontaneous discharges that waxed and waned in amplitude and frequency, consistent with myotonic discharges. A high impact 8‐base pair (bp) deletion across the end of exon 3 and intron 3 of the chloride voltage‐gated channel 1 (CLCN1) gene was identified using whole genome sequencing.Treatment and OutcomePhenytoin treatment was initiated at 3 mg/kg po q24 h and resulted in long‐term improvement.Clinical RelevanceThis novel mutation within the CLCN1 gene is a cause of myotonia congenita in cats and we report for the first time its successful treatment.}, journal={JOURNAL OF VETERINARY INTERNAL MEDICINE}, author={Woelfel, Christian and Meurs, Kathryn and Friedenberg, Steven and DeBruyne, Nicole and Olby, Natasha J.}, year={2022}, month={Jul} }
 @article{mancini_early_slater_olby_mariani_munana_woelfel_schacher_zhong_messenger_2022, title={Novel subcutaneous cytarabine infusion with the Omnipod system in dogs with meningoencephalomyelitis of unknown etiology}, volume={83}, ISSN={["1943-5681"]}, DOI={10.2460/ajvr.22.03.0046}, abstractNote={Abstract

OBJECTIVE
To investigate the feasibility and pharmacokinetics of cytarabine delivery as a subcutaneous continuous-rate infusion with the Omnipod system.


ANIMALS
6 client-owned dogs diagnosed with meningoencephalomyelitis of unknown etiology were enrolled through the North Carolina State University Veterinary Hospital.


PROCEDURES
Cytarabine was delivered at a rate of 50 mg/m2/hour as an SC continuous-rate infusion over 8 hours using the Omnipod system. Plasma samples were collected at 0, 4, 6, 8, 10, 12, and 14 hours after initiation of the infusion. Plasma cytarabine concentrations were measured by high-pressure liquid chromatography. A nonlinear mixed-effects approach generated population pharmacokinetic parameter estimates.


RESULTS
The mean peak plasma concentration (Cmax) was 7,510 ng/mL (range, 5,040 to 9,690 ng/mL; SD, 1,912.41 ng/mL), average time to Cmax was 7 hours (range, 4 to 8 hours; SD, 1.67 hours), terminal half-life was 1.13 hours (SD, 0.29 hour), and the mean area under the curve was 52,996.82 hours X μg/mL (range, 35,963.67 to 71,848.37 hours X μg/mL; SD, 12,960.90 hours X μg/mL). Cmax concentrations for all dogs were more than 1,000 ng/mL (1.0 μg/mL) at the 4-, 6-, 8-, and 10-hour time points.


CLINICAL RELEVANCE
An SC continuous-rate infusion of cytarabine via the Omnipod system is feasible in dogs and was able to achieve a steady-state concentration of more than 1 μg/mL 4 to 10 hours postinitiation of cytarabine and a Cmax of 7,510 ng/mL (range, 5,040 to 9,690 ng/mL; SD, 1,912.41 ng/mL). These are comparable to values reported previously with IV continuous-rate infusion administration in healthy research Beagles and dogs with meningoencephalomyelitis of unknown etiology.
}, number={9}, journal={AMERICAN JOURNAL OF VETERINARY RESEARCH}, author={Mancini, Shelby L. and Early, Peter J. and Slater, Bailey M. and Olby, Natasha J. and Mariani, Christopher L. and Munana, Karen R. and Woelfel, Christian W. and Schacher, Jordan A. and Zhong, Li and Messenger, Kristen M.}, year={2022}, month={Sep} }
 @article{sparks_woelfel_robertson_olby_2021, title={Association between filum terminale internum length and pain in Cavalier King Charles spaniels with and without syringomyelia}, volume={35}, ISSN={["1939-1676"]}, url={https://doi.org/10.1111/jvim.16023}, DOI={10.1111/jvim.16023}, abstractNote={AbstractBackgroundLumbar syringomyelia (SM), lumbosacral pain, and more caudal spinal cord termination are reported in Cavalier King Charles spaniels (CKCS). Data are lacking on the clinical relevance of alterations in their spinal cord terminal structures.ObjectivesTo compare spinal cord termination level and filum terminale internum length (FTIL) with presence of lumbar SM and clinical signs in CKCS.AnimalsForty‐eight CKCS.MethodsIn this prospective study, pain was quantified using owner and clinician assessments. Vertebral level of spinal cord and dural sac termination, presence of SM, and FTIL were determined from sagittal magnetic resonance imaging (MRI) sequences. Kappa and intraclass correlation (ICC) analyses determined interobserver reliability. The MRI findings were compared to owner and clinician‐reported pain quantification.ResultsInterobserver reliability was good for spinal cord and dural sac termination (kappa = 0.61 and 0.64, respectively) and excellent for FTIL (ICC: 92% agreement). The spinal cord terminated at 6th lumbar vertebra in 1, 7th lumbar vertebra in 31, and the sacrum in 15 dogs, and termination level was associated with lumbar SM (P = .002) but not clinical signs. Mean FTIL was 2.9 ± 1.08 mm; it was associated with owner‐reported pain (P = .033) and spinal palpation scores (P = .023). Painful CKCS without SM had shorter FTIL compared to normal CKCS and painful CKCS with SM (P = .02).ConclusionsPainful CKCS without SM have decreased distance between the termination of the spinal cord and dural sac, suggesting a shorter FTIL. More caudal spinal cord termination is associated with development of lumbar SM.}, number={1}, journal={JOURNAL OF VETERINARY INTERNAL MEDICINE}, author={Sparks, Courtney R. and Woelfel, Christian and Robertson, Ian and Olby, Natasha J.}, year={2021}, month={Jan}, pages={363–371} }
 @article{woelfel_robertson_mariani_munana_early_olby_2021, title={Outcomes and prognostic indicators in 59 paraplegic medium to large breed dogs with extensive epidural hemorrhage secondary to thoracolumbar disc extrusion}, volume={50}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.13592}, abstractNote={AbstractObjectiveTo evaluate outcomes and prognostic factors after decompressive hemilaminectomy in paraplegic medium to large breed dogs with extensive epidural hemorrhage (DEEH) and thoracolumbar intervertebral disc extrusion (TL‐IVDE).Study designRetrospective, cohort, descriptive study.AnimalsFifty‐nine client‐owned dogs.MethodsMedical records and advanced imaging were reviewed for paraplegic dogs with DEEH. Ambulatory status 6 months after surgery and postoperative complications were recorded. Multiple logistic regression models were constructed to explore prognostic factors.ResultsRecords of 22 dogs with and 37 dogs without pelvic limb pain perception at presentation were included. Median age of dogs was 5 years (interquartile range, 4‐7), and mean weight was 26.9 kg (SD, ±9.71). Labradors and Labrador mixes were most common (17/59 [28.8%]). Recovery of ambulation occurred in 17 of 22 (77.3%) dogs with and in 14 of 37 (37.8%) dogs without pain perception prior to surgery. Progressive myelomalacia was recorded in three of 59 (5.1%) dogs, one with pain perception and two without pain perception at presentation. Postoperative complications (14/59 [23.7%]) were common. Factors independently associated with outcome included clinical severity (odds ratio [OR] 0.179, P = .005), number of vertebrae with signal interruption in half Fourier single‐shot turbo spin‐echo sequences (HASTEi; OR, 0.738; P = .035), and ratio of vertebral sites decompressed to HASTEi (OR, 53.79; P = .03).ConclusionParaplegic medium to large breed dogs with DEEH have a less favorable outcome after surgical decompression than paraplegic dogs with TL‐IVDE.Clinical significanceDogs with DEEH can have severe postoperative complications. Loss of pain perception and increased HASTEi are associated with a poor outcome, while more extensive decompression improves outcome.}, number={3}, journal={VETERINARY SURGERY}, author={Woelfel, Christian W. and Robertson, James B. and Mariani, Chris L. and Munana, Karen R. and Early, Peter J. and Olby, Natasha J.}, year={2021}, month={Apr}, pages={527–536} }
 @article{woelfel_bray_early_mariani_olby_2021, title={Subaxial cervical articular process subluxation and dislocation: Cervical locked facet injuries in dogs}, volume={11}, ISSN={["1532-950X"]}, DOI={10.1111/vsu.13746}, abstractNote={AbstractObjectiveTo describe neurologic signs, diagnostic imaging findings, potential treatments, and outcomes in dogs with subaxial cervical articular process subluxation and dislocation, or a “locked facet.”Study designRetrospective case series.AnimalsTen client‐owned dogs.MethodsDogs with a diagnosis of cervical locked facets were identified through medical records and imaging reports searches. Data on presenting signs, diagnostic findings, treatment, and outcome were recorded.ResultsAll cases were small or toy‐breed dogs with preceding trauma. Four dogs were tetraplegic with intact pain perception, five were nonambulatory tetraparetic, and one was ambulatory tetraparetic, with half of the tetraparetic dogs having worse motor function in the thoracic limbs. The only sites affected were C5/6 (n = 6) and C6/7 (n = 4). All dogs had unilateral dorsal displacement of the cranial articular process of the caudal vertebra relative to the caudal articular process of the cranial vertebra at the luxation site. Five dogs were treated surgically, three by external coaptation, one by restriction, and one was euthanized the day after diagnosis. All dogs with outcome data (n = 8) became ambulatory. Nonambulatory dogs returned to ambulation in a median of 4 weeks (IQR 1‐12; range 1‐28).ConclusionIn these dogs, locked facet injuries affected the caudal cervical vertebrae in small breeds and could be identified on imaging through the presence of dorsal displacement of a cranial articular process. Our small cohort had a functional recovery regardless of treatment.Clinical signiicanceLocked facet injuries should be a differential for small or toy‐breed dogs with a cervical myelopathy secondary to trauma.}, journal={VETERINARY SURGERY}, author={Woelfel, Christian W. and Bray, Katherine Y. and Early, Peter J. and Mariani, Christopher L. and Olby, Natasha J.}, year={2021}, month={Nov} }