@article{billingsley_inscoe_attia_lu_zhou_lee_2024, title={Stationary prospective cardiac gated computed tomography-dynamic study in phantoms and <i>in vivo</i>}, volume={69}, ISSN={["1361-6560"]}, DOI={10.1088/1361-6560/ad62d1}, abstractNote={Abstract This study explores the feasibility of a stationary gantry cardiac gated computed tomography (CT) with carbon nanotube (CNT) linear x-ray source arrays. Conventional rotational CTs are limited by the rotational forces on the rapidly spinning gantries. We have recently developed a stationary gantry CT system utilizing the multipixel CNT x-ray sources. As these sources also enable straightforward x-ray pulse control, we sought to explore the potential for performing gated prospective imaging with our stationary CT system. Prospective respiratory and cardiac gating control was implemented and the system was evaluated with dynamic phantom imaging studies followed by imaging of a porcine model with cardiac and respiratory gating. The findings revealed minimal motion artifacts, confirming successful physiologic gated acquisition in stationary gantry cardiac CT, showing the potential of this imaging approach.
}, number={16}, journal={PHYSICS IN MEDICINE AND BIOLOGY}, author={Billingsley, Alex and Inscoe, Christina and Attia, Mohamed Fathy and Lu, Jianping and Zhou, Otto and Lee, Yueh Z.}, year={2024}, month={Aug} }
 @article{inscoe_billingsley_zhao_burel_chesser_lyda_lu_lee_zhou_2024, title={X-ray source array optimization for mobile chest tomosynthesis}, volume={12925}, ISBN={["978-1-5106-7154-6"]}, ISSN={["1605-7422"]}, DOI={10.1117/12.3006912}, journal={MEDICAL IMAGING 2024: PHYSICS OF MEDICAL IMAGING, PT 1}, author={Inscoe, Christina and Billingsley, Alex and Zhao, Alan and Burel, Heaven Laramy-Jade and Chesser, Stephen and Lyda, Gavin and Lu, Jianping and Lee, Yueh and Zhou, Otto}, year={2024} }
 @article{inscoe_billingsley_puett_zhou_lu_lee_2022, title={Patient-specific scatter-corrected digital chest tomosynthesis in human subjects}, volume={12031}, ISBN={["978-1-5106-4937-8"]}, ISSN={["1996-756X"]}, DOI={10.1117/12.2611585}, abstractNote={Purpose: Digital chest tomosynthesis is an attractive alternative to computed tomography (CT) for some clinical tasks but lacks the sensitivity for detection of small lung nodules due to scattered radiation. Conventional scatter mitigation techniques are not ideal. The purpose of this study was to provide an update on a human imaging study in patients with lung lesions incorporating an alternative scatter correction method. Method: Human subjects with known lung lesions were imaged with an experimental stationary digital chest tomosynthesis (s-DCT) system. A customized primary sampling device (PSD) was used to collect sparse primary beam samples prior to the normal scan. A primary sampling scatter correction (PSSC) algorithm was used to compute scatter and correct projections prior to reconstruction. Reconstruction image quality was evaluated in both scatter-corrected and uncorrected images and compared to clinical CT images by a board-certified radiologist. Results: Scatter corrected reconstruction slice images were found to exhibit improved conspicuity of a ground glass opacity in one example case. Pulmonary vasculature was also enhanced in a subject with high body mass index. These example cases are shown with quantitative evaluation. Reconstruction slice images with scatter correction exhibit greater uniformity in histogram distribution, allowing visualization of a larger range of anatomy at any window and level than their corresponding uncorrected counterparts. Conclusions: A low-dose, patient-specific scatter correction has been demonstrated in thirty-eight subjects in a human imaging study. The PSSC technique was found to enhance visualization and improve overall reconstruction image quality. A comprehensive reader study will determine clinical efficacy.}, journal={MEDICAL IMAGING 2022: PHYSICS OF MEDICAL IMAGING}, author={Inscoe, Christina R. and Billingsley, Alex J. and Puett, Connor and Zhou, Otto and Lu, Jianping and Lee, Yueh}, year={2022} }
 @article{inscoe_lee_billingsley_puett_nissman_lu_zhou_2021, title={Point-of-Care Tomosynthesis Imaging of the Wrist}, volume={186}, ISSN={["1930-613X"]}, DOI={10.1093/milmed/usaa337}, abstractNote={ABSTRACT
               
                  Introduction
                  Musculoskeletal injury to extremities is a common issue for both stateside and deployed military personnel, as well as the general public. Superposition of anatomy can make diagnosis difficult using standard clinical techniques. There is a need for increased diagnostic accuracy at the point-of-care for military personnel in both training and operational environments, as well as assessment during follow-up treatment to optimize care and expedite return to service. Orthopedic tomosynthesis is rapidly emerging as an alternative to digital radiography (DR), exhibiting an increase in sensitivity for some clinical tasks, including diagnosis and follow-up of fracture and arthritis. Commercially available digital tomosynthesis systems are large complex devices. A compact device for extremity tomosynthesis (TomoE) was previously demonstrated using carbon nanotube X-ray source array technology. The purpose of this study was to prepare and evaluate the prototype device for an Institutional Review Board-approved patient wrist imaging study and provide initial patient imaging results.
               
               
                  Materials and Methods
                  A benchtop device was constructed using a carbon nanotube X-ray source array and a flat panel digital detector. Twenty-one X-ray projection images of cadaveric specimens and human subjects were acquired at incident angles from −20 to +20 degrees in various clinical orientations, with entrance dose calibrated to commercial digital tomosynthesis wrist scans. The projection images were processed with an iterative reconstruction algorithm in 1 mm slices. Reconstruction slice images were evaluated by a radiologist for feature conspicuity and diagnostic accuracy.
               
               
                  Results
                  The TomoE image quality was found to provide more diagnostic information than DR, with reconstruction slices exhibiting delineation of joint space, visual conspicuity of trabecular bone, bone erosions, fractures, and clear depiction of normal anatomical features. The scan time was 15 seconds and the skin entrance dose was verified to be 0.2 mGy.
               
               
                  Conclusions
                  The TomoE device image quality has been evaluated using cadaveric specimens. Dose was calibrated for a patient imaging study. Initial patient images depict a high level of anatomical detail and an increase in diagnostic value compared to DR.
               }, journal={MILITARY MEDICINE}, author={Inscoe, Christina R. and Lee, Yueh and Billingsley, Alex J. and Puett, Connor and Nissman, Daniel and Lu, Jianping and Zhou, Otto}, year={2021}, pages={745–750} }
 @article{inscoe_puett_billingsley_zhou_lu_lee_2021, title={Evaluation of patient-specific scatter-corrected digital chest tomosynthesis}, volume={11312}, ISSN={["1605-7422"]}, DOI={10.1117/12.2549316}, abstractNote={Purpose: Chest tomosynthesis is an attractive alternative to computed tomography (CT) for lung nodule screening, but reductions in image quality caused by radiation scatter remains an important limitation. Conventional anti-scatter grids result in higher patient dose, and alternative approaches are needed. The purpose of this study was to validate a lowdose patient-specific approach to scatter correction for an upcoming human imaging study. Method: A primary sampling device (PSD) was designed and scatter correction algorithm incorporated into an experimental stationary digital chest tomosynthesis (s-DCT) system for this study to directly compute scatter from the primary beam information. Phantom and an in-vivo porcine subject were imaged. Total scan time was measured and image quality evaluated. Results: Comparison of reconstruction slice images from uncorrected and scatter-corrected projection images reveals improved image quality, with increased feature conspicuity. Each scan in the current setup required twelve seconds, in addition to one second for PSD retraction, for a total scan time of 25 seconds. Conclusions: We have evaluated the prototype low-dose, patient-specific scatter correction methodology using phantom studies in preparation for a clinical trial. Incorporating only 5% of additional patient dose, the reconstruction slices exhibit increased visual conspicuity of anatomical features, with the primary drawback of increased total scan time. Though used for tomosynthesis, the technique can be easily translated to digital radiography in lieu of an anti-scattering grid.}, journal={MEDICAL IMAGING 2020: PHYSICS OF MEDICAL IMAGING}, author={Inscoe, Christina R. and Puett, Connor and Billingsley, Alex J. and Zhou, Otto and Lu, Jianping and Lee, Yueh Z.}, year={2021} }
 @article{inscoe_billingsley_puett_nissman_lu_lee_zhou_2021, title={Preliminary imaging evaluation of a compact tomosynthesis system for potential point-of-care extremity imaging}, volume={11312}, ISSN={["1605-7422"]}, DOI={10.1117/12.2549329}, abstractNote={Orthopedic tomosynthesis is emerging as an attractive alternative to digital radiography (DR), with increased sensitivity for some clinical tasks, including fracture diagnosis and staging and follow-up of arthritis. Commercially available digital tomosynthesis (DTS) systems are complex, room-sized devices. A compact tomosynthesis system for extremity imaging (TomoE) was previously demonstrated using carbon nanotube (CNT) x-ray source array technology. The purpose of this study was to evaluate the prototype device in preparation for an Institutional Review Board (IRB)- approved patient imaging study and evaluate initial patient images. A tabletop device was constructed using a short CNT x-ray source array, operated in three positions, and a flat panel digital detector. Twenty-one x-ray projection images were acquired at incident angles from -20 to +20 degrees in various clinical orientations, with entrance doses matched to commercial in-room DTS scanners. The projection images were reconstructed with an iterative reconstruction technique in 1mm slices. Cadaveric specimen and initial participant images were reviewed by radiologists for feature conspicuity and diagnostic accuracy. TomoE image quality was found to be superior to DR, with reconstruction slices exhibiting visual conspicuity of trabecular bone, delineation of joint space, bone erosions, fractures, and clear depiction of normal anatomical features. The scan time was fifteen seconds with mechanical translation. Skin entrance dose was verified to be 0.2mGy. TomoE device image quality has been evaluated in cadaveric specimens and dose was calibrated for a patient imaging study. Initial patient images depict a high level of anatomical detail an increase in diagnostic value compared to DR.}, journal={MEDICAL IMAGING 2020: PHYSICS OF MEDICAL IMAGING}, author={Inscoe, Christina R. and Billingsley, Alex J. and Puett, Connor and Nissman, Daniel and Lu, Jianping and Lee, Yueh Z. and Zhou, Otto Z.}, year={2021} }
 @article{inscoe_billingsley_puett_feinstein_gunnell_nissman_maetani_draeger_lu_lee_et al._2019, title={Tomosynthesis imaging of the wrist using a CNT x-ray source array}, volume={10948}, ISSN={["1996-756X"]}, DOI={10.1117/12.2512906}, abstractNote={Tomosynthesis imaging has been demonstrated as an alternative to MRI and CT for orthopedic imaging. Current commercial tomosynthesis scanners are large in-room devices. The goal of this study was to evaluate the feasibility of designing a compact tomosynthesis device for extremity imaging at the point-of-care utilizing a carbon nanotube (CNT) x-ray source array. The feasibility study was carried out using a short linear CNT source array with limited number of x-ray emitting focal spots. The short array was mounted on a translation stage and moved linearly to mimic imaging configurations with up to 40 degrees angular coverage at a source-to-detector distance of 40cm. The receptor was a 12x12cm flat panel digital detector. An anthropomorphic phantom and cadaveric wrist specimens were imaged at 55kVp under various exposure conditions. The projection images were reconstructed with an iterative reconstruction algorithm. Image quality was assessed by musculoskeletal radiologists. Reconstructed tomosynthesis slice images were found to display a higher level of detail than projection images due to reduction of superposition. Joint spaces and abnormalities such as cysts and bone erosion were easily visualized. Radiologists considered the overall utility of the tomosynthesis images superior to conventional radiographs. This preliminary study demonstrated that the CNT x-ray source array has the potential to enable tomosynthesis imaging of extremities at the point-of-care. Further studies are necessary to optimize the system and x-ray source array configurations in order to construct a dedicated device for diagnostic and interventional applications.}, journal={MEDICAL IMAGING 2019: PHYSICS OF MEDICAL IMAGING}, author={Inscoe, Christina R. and Billingsley, A. and Puett, C. and Feinstein, S. and Gunnell, E. and Nissman, D. and Maetani, T. and Draeger, R. and Lu, J. and Lee, Y. and et al.}, year={2019} }