| 16:00 | 0299.
 | Brain temperature and its relation to cognitive status in traumatic brain injury: a whole-brain magnetic resonance spectroscopic imaging study Maho Kitagawa1, Kagari Abiko2,3, Sulaiman Sheriff4, Andrew A Maudsley4, Daisuke Sawamura5, and Khin Khin Tha1,6
1Department of Biomarker imaging Science, Graduate School of Biomedical Science and Engineering, Hokkaido University, Sapporo, Japan, 2Department of Rehabilitation, Hokkaido University Hospital, Sapporo, Japan, 3Department of Rehabilitation, Sapporo Azabu Neurosurgical Hospital, Sapporo, Japan, 4Department of Radiology, University of Miami School of Medicine, Miami, FL, United States, 5Department of Rehabilitation Science, Hokkaido University Faculty of Health Sciences, Sapporo, Japan, 6Global Center for Biomedical Science and Engineering, Faculty of Medicine, Hokkaido University, Sapporo, Japan Keywords: Traumatic Brain Injury, Thermometry, Brain temperature Motivation: The long-term outcome, i.e., the impact of injury on life, may be underestimated in patients with mild-to-moderate TBI. Cognitive deficit, a sequela of TBI and a significant social burden, is difficult to assess in uncooperative patients. Goal(s): To compare brain temperature between control and TBI groups, and to assess the relationship between brain temperature and cognitive status in TBI group. Approach: Brain temperature of patients was estimated noninvasively by WB-MRSI and compared to controls; the association between brain temperature and cognitive status was also assessed in the TBI group. Results: Significant brain temperature reductions in the TBI group were associated with cognitive decline. Impact: The
strong correlation between brain temperature and cognitive performance in the
TBI group indicates that attention decreases as brain temperature decreases.
Brain temperature may become as a quantitative indicator of cognitive status in
patients with subacute to chronic TBI. |
| 16:12 | 0300.
 | The Rugby Connectome: A Longitudinal Analysis of Structural Connectivity in an Adolescent Cohort with Repeated Head Impacts Edward John Clarkson1,2, Maryam Tayebi1,2, William S. Schierding2,3,4, Paul Condron2, Leigh Potter2, Jerome Maller5, Miao Qiao6, Justin Fernandez1, Samantha Holdsworth2,7, Eryn E. Kwon1,2,7, Joshua P. McGeown2,7, and Vickie Shim1,2
1Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand, 2Mātai Medical Research Institute, Tairāwhiti-Gisborne, New Zealand, 3Department of Ophthalmology, University of Auckland, Auckland, New Zealand, 4Vision Research Foundation, Auckland, New Zealand, 5General Electric Healthcare, Victoria, Australia, 6School of Computer Science, Faculty of Science, University of Auckland, Auckland, New Zealand, 7Faculty of Medical and Health Sciences & Centre for Brain Research, University of Auckland, Auckland, New Zealand Keywords: Structural Connectivity, Adolescents Motivation: Evidence suggests that repeated head impacts which do not produce conscious changes in cognition, may have detrimental effects on neurological function and brain micro-structure. Goal(s): Our study aims to quantify longitudinal changes in structural connectivity within a cohort of young rugby players throughout a rugby season. Approach: Using head impact data and advanced MRI techniques including whole brain tractography from multi-shell diffusion MRI, structural connectivity adjacency matrices were derived from tractograms and analyzed using graph theory. Results: Global clustering coefficient increased significantly from preseason to mid-season and post-season. These changes correlated with measures of cumulative head impact exposure. Impact: Data from our
adolescent rugby cohort offers a rare opportunity to document the longitudinal
effect of repeated head impact exposure on structural connectivity. The
structural connectivity changes we observed may not be indicative of clinically
relevant brain injury. |
| 16:24 | 0301.
 | Association of white matter brain diffusivity properties with football exposure in former professional American-style football players Ona Wu1, Rachel Grashow2, Marc Weisskopf2, Karen Miller3, Grant Iverson4, Jacob A Dodelson1, Annelise M Kulpanowski1, Brandon L Hancock1, Michael Doyle5, William A Copen6, Aaron Baggish7, and Ross Zafonte5
1Athinoula A Martinos Center for Medical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, 2Harvard T. H. Chan School of Public Health, Boston, MA, United States, 3Neuroendocrine Unit, Massachusetts General Hospital, Boston, MA, United States, 4Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital, Charlestown, MA, United States, 5Football Players Health Study, Harvard Medical School, Boston, MA, United States, 6Department of Radiology, Massachusetts General Hospital, Boston, MA, United States, 7Cardiology Division, Massachusetts General Hospital, Boston, MA, United States Keywords: Traumatic Brain Injury, Traumatic brain injury Motivation: The possible long-term effects of repetitive head impacts experienced by American-style professional football players are poorly understood. White matter injury is a known sequela of head trauma. Peak-width skeletonized mean diffusivity measurements have been associated with cerebrovascular disease. Goal(s): Our goal is to evaluate the association of peak-width skeletonized diffusion values with football exposure. Approach: We measured peak-width skeletonized diffusion values in 103 retired professional football players who underwent multi-shell diffusion imaging. Results: Age, hypertension, body-mass index, concussion signs and symptom history score, total years of non-professional play, and episodes of loss of consciousness were significantly associated with peak-width skeletonized diffusion values. Impact: Measured peak-width skeletonized diffusion values in white matter may provide an improved understanding of the association between football exposure and later-in-life brain microstructural integrity. |
| 16:36 | 0302.
 | Acute impact of soccer ball heading on brain tissue electrical conductivity Jun Cao1, Nathan Delang2,3,4,5, Luke Henderson5, Rebecca Robertson5, Fernando Tinoco Mendoza5, Ben Desbrow2, Christopher Irwin2,6, Elizabeth Cairns4,7, Paul Austin5, Shane Ball4, Michael Buckland4, Iain McGregor4,7, Danielle McCartney1,4,7, and Caroline Rae1,8
1Neuroscience Research Australia, Sydney, Australia, 2School of Health Sciences and Social Work, Griffith University, Gold Coast, Australia, 3Queensland Academy of Sport, Queensland, Australia, 4School of Psychology, Faculty of Science, The University of Sydney, Sydney, Australia, 5School of Medical Sciences (Neuroscience), Faculty of Medicine and Health, The University of Sydney, Sydney, Australia, 6Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia, 7Lambert Initiative for Cannabinoid Therapeutics, The University of Sydney, Sydney, Australia, 8School of Psychology, The University of New South Wales, Sydney, Australia Keywords: Traumatic Brain Injury, Brain Motivation: The effects of sub-concussive head impacts are not well understood. New biomarkers are needed to detect sub-concussion. Goal(s): Our goal was to investigate the acute effects of sub-concussive impacts using MREPT. Approach: Fourteen soccer players were scanned with MREPT in two separate sessions after performing the task of either heading or kicking soccer balls for 20 minutes. Results: Electrical conductivity measured in multiple brain regions such as inferior fronto-occipital fasciculus after the heading session was significantly less than that measured following kicking, indicating that MREPT could be a useful tool for detecting sub-concussive injury. Impact: The finding that heading soccer balls for a short period can cause
significant acute decreases in brain electrical conductivity suggests that this
activity may have detrimental short term effects on brain function. |
| 16:48 | 0303.
 | Evaluation of MR Elastography-Based Biomarkers for Detecting Skull-Brain Interface Decoupling Changes in Response to Repetitive Head Impacts Xiang Shan1, Matthew Murphy1, Yi Sui1, Keni Zheng1, Emi Hojo1, Armando Manduca2, Richard Ehman1, John Huston III1, and Ziying Yin1
1Radiology, Mayo Clinic, Rochester, MN, United States, 2Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States Keywords: Traumatic Brain Injury, Traumatic brain injury, Repetitive head impacts, Magnetic resonance elastography Motivation: The growing concern about subconcussive, repetitive head impacts (RHI) has prompted the need for non-invasive RHI detection methods. Goal(s): To understand if there are alterations of the skull-brain interface due to RHI exposure and explore potential imaging biomarkers for characterizing RHI. Approach: Four MR Elastography (MRE)-based parameters were compared between RHI(-) and RHI(+) groups, encompassing assessment of cortical stiffness, capabilities of motion dampening, and strain mediation at the skull-brain interface. Results: Our findings revealed increased cortical stiffness, rotational transmission ratio, and adjusted NOSS in individuals with high RHI exposure, suggesting a degeneration of the skull-brain interface decoupling performance. Impact: This study sheds light on RHI-induced changes at the skull-brain interface, proposing three potential non-invasive biomarkers for monitoring such alterations. These findings hold promise for aiding medical professionals in identifying individuals at high RHI exposure risk. |
| 17:00 | 0304.
 | Quantifying changes of axonal shape in traumatic brain injury with time-dependent diffusion Ali Abdollahzadeh1,2, Ricardo Coronado-Leija1,2, Hong-Hsi Lee3, Alejandra Sierra4, Els Fieremans1,2, and Dmitry S. Novikov1,2
1Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York, NY, United States, 2Center for Advanced Imaging Innovation and Research, New York University Grossman School of Medicine, New York, NY, United States, 3Department of Radiology, Harvard Medical School, Boston, MA, United States, 4A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland Keywords: Microstructure, Modelling, Axons, Diffusion, Validation, TBI, Segmentation, Electron microscopy Motivation: Interpreting diffusion MRI (dMRI) in terms of brain tissue micro-geometry. Goal(s): To identify cellular features that govern diffusion measurements among myriads of parameters specifying tissue microstructure. Approach: We found how axonal micro-geometry is manifested in a dMRI measurement by analytically solving the diffusion equation in a tube with a randomly varying cross-section. Results: We identify a specific power-law approach of the time-dependent diffusion coefficient along the axon to its long-time limit. The average inverse cross-section and the variance of long-range cross-sectional fluctuations govern the diffusive dynamics. We quantify changes in these non-trivial geometrical features, associated with axonal beading, in a rat TBI model. Impact: Beading is a characteristic feature of numerous neurodegenerative diseases triggered by different pathological conditions and injuries. Here, we detect geometrical changes in the axonal micro-geometry, accessible via the along-tract diffusivity from the diffusion tensor using clinically feasible diffusion weightings. |
| 17:12 | 0305.
 | Spinal cord injury and the patterns of neuronal plasticityduring motor-rehabilitation training Tim Max Emmenegger1, Gergely David1, Tim Killeen1, and Patrick Freund1,2,3
1Spinal Cord Injury Center Balgrist University Hospital, Zurich, Switzerland, 2Wellcome Centre for Human Neuroimaging, UCL Queen Square Institute of Neurology, London, United Kingdom, 3Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany Keywords: Other Neurodegeneration, Brain, Myelin plasticity; Multiparametric mapping; Magnetisation transfer; Motor learning; Quantitative MRI; Corticospinal tract; Hippocampus Motivation: Rehabilitation following spinal cord injury is currently the only means to improve motor function. How macro-and microstructural changes in the CNS promote such recovery is understudied. Goal(s): Investigate training-induced plasticity during motor skill training and explore associations between neuroplasticity and performance. Approach: We compared healthy and SCI trainees and healthy non-trainees using quantitative and diffusion MRI, and associated changes in MRI parameters with performance improvement. Results: SCI patients showed training-induced changes in cortical and subcortical areas, which were akin to those in healthy controls and were linked to specific aspects of motor skill learning. Impact: Motor skill learning in SCI induces neuroplasticity in similar areas as seen in healthy controls. These findings open the possibility to monitor progress in neurorehabilitation. |
| 17:24 | 0306.
 | Automatic segmentation of T2-weighted hyperintense lesions in spinal cord injury Jan Valosek1,2,3,4, Naga Karthik Enamundram1,2, Maxime Bouthillier1,5, Simon Schading-Sassenhausen6, Lynn Farner6, Dario Pfyffer6,7, Andrew C. Smith8, Kenneth A. Weber II7, Patrick Freund6,9, and Julien Cohen-Adad1,2,10,11
1NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada, 2Mila - Quebec AI Institute, Montreal, QC, Canada, 3Department of Neurosurgery, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic, 4Department of Neurology, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic, 5Centre Hospitalier de l’Université de Montréal, University of Montreal, Montreal, QC, Canada, 6Spinal Cord Injury Center, Balgrist University Hospital, University of Zürich, Zürich, Switzerland, 7Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Standford, CA, United States, 8Department of Physical Medicine and Rehabilitation Physical Therapy Program, University of Colorado School of Medicine, Aurora, CO, United States, 9Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, 10Functional Neuroimaging Unit, CRIUGM, Université de Montréal, Montreal, QC, Canada, 11Centre de Recherche du CHU Sainte-Justine, Université de Montréal, Montreal, QC, Canada Keywords: Analysis/Processing, Spinal Cord, Deep Learning; Spinal Cord Injury; Segmentation Motivation: Morphometric analysis of the intramedullary lesion following spinal cord injury will assist in understanding the extent of the injury and choosing the best therapeutic strategy for rehabilitation. Goal(s): Our objective was to develop a deep learning-based tool for the segmentation of T2-weighted hyperintense spinal cord injury lesions. Approach: A nnUNet model was trained to segment both the spinal cord and lesions from two different datasets. Results: Compared to existing methods, our model achieved the best segmentation performance for both cord and lesions. The code/model is available on GitHub and will soon be part of the Spinal Cord Toolbox. Impact: Automatic segmentation of spinal cord injury lesions replaces the tedious process of manual annotation and enables the extraction of relevant lesion morphometrics in large cohorts. The proposed model generalizes across lesion etiologies (traumatic/ischemic), scanner manufacturers and heterogeneous image resolutions. |
| 17:36 | 0307.
 | Whole cord diffusion imaging of post-mortem human spinal cord injury reveals extent and potential timeline of axonal swelling and degeneration Nikolai Lesack1,2,3, Sarah Rosemary Morris1,2,3, Taylor Swift-LaPointe2, Andrew Yung1,3,4, Valentin Prevost1,3,4, Shana George5, Andrew Bauman4, Piotr Kozlowski1,2,3,4, Farah Samadi1,5, Caron Fournier1,5, Lisa Parker6, Kevin Dong1, Femke Streijger1, G.R. Wayne Moore1,5,6, Adam Velenosi1, Veronica Hirsch-Reinshagen1,5,6, Brian Kwon1,7, and Cornelia Laule1,2,3,5
1International Collaboration on Repair Discoveries, Vancouver, BC, Canada, 2Physics and Astronomy, The University of British Columbia, Vancouver, BC, Canada, 3Radiology, The University of British Columbia, Vancouver, BC, Canada, 4Faculty of Medicine, UBC MRI Research Centre, Vancouver, BC, Canada, 5Pathology & Laboratory Medicine, The University of British Columbia, Vancouver, BC, Canada, 6Vancouver General Hospital, Vancouver, BC, Canada, 7Orthopaedics, The University of British Columbia, Vancouver, BC, Canada Keywords: Microstructure, Spinal Cord, White Matter, Traumatic Injury, ActiveAx, Spinal Cord Injury, DTI, Myelin, Axons Motivation: Following spinal cord injury (SCI) changes in tissue microstructure occur throughout the length of the cord which are not detectable with conventional MRI. Goal(s): To characterize whole cord diffusion MRI metrics in human SCI post-mortem tissue, including the effect of injury-to-death interval on diffusion MRI metrics. Approach: Two full-length spinal cords were imaged at 7T. DTI and ActiveAx metrics were extracted from white matter tracts. Results: Changes in fractional anisotropy, axon density, and axon diameter were observed downstream of the injury epicentre in the case with a longer injury-to-death interval. Transience in diffusion metrics may indicate the extent of axonal degeneration and swelling. Impact: Diffusion MRI may be a useful tool in understanding the extent and progression of spinal cord injury. Insight into axonal swelling and degeneration following spinal cord injury could aid clinicians in predicting patient prognosis. |
| 17:48 | | Discussion |