Julien Cohen-Adad

Paul Hoareau

Maîtrise recherche - Polytechnique

paul.hoareau@mila.quebec

youssef.laatar@mila.quebec

Youssef Laatar

Maîtrise recherche - Polytechnique

nathan.molinier@mila.quebec

Nathan Molinier

Doctorat - Polytechnique

Publications

Upper cervical spinal cord morphometric charts: from population references to individualized clinical assessment

Jiajia Wang

Tiantian Hua

Haiyan Wu

Rui Zhang

Siyao Xu

Cong Zhang

Li Chai

Yajun Yao

Tianyu Gao

Lu Bai

Xiaozhou Du

Chao Zhang

Bingjie Lin

Lifang Liao

Huiying Wang

Yuqi Luo

Xiaoqin Zhu

Demao Deng

Yuankui Wu

Renlong Zhang … (voir 14 de plus)

Zhiqiang Zhang

Fuqing Zhou

Jiajia Zhu

Xi‐Nian Zuo

Shufang Cheng

Xiaona Xia

Xiangshui Meng

Yazhuo Kong

Julien Cohen‐Adad

Ruomi Guo

Shuiwei Xia

Yunyun Duan

Zhizheng Zhuo

Yaou Liu

Abstract The upper cervical spinal cord is essential for motor, sensory and autonomic function, yet its normative morphometric trajectories … (voir plus)and disease-related deviations remain unclear. Using three-dimensional T1-weighted images from 10,159 healthy individuals aged 8-85 years, we established normative references for averaged and level-specific upper cervical spinal cord morphometry, revealing measure-specific trajectories with peak ages of 29.7-44.1 years. These references were applied to 2,394 patients with seven neurological disorders: mild cognitive impairment, Alzheimer’s disease, Parkinson’s disease, cerebral small vessel disease, multiple sclerosis, neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein antibody-associated disease to derive individualized deviation scores. These deviation scores captured disease-specific abnormalities, enabled disease classification, and were associated with cognition, physical disability and disease progression. Finally, a personalized upper cervical spinal cord report was developed to support individualized imaging interpretation. Together, these findings provide a normative framework for quantifying upper cervical spinal cord morphometry and advancing personalized assessment across neurological disorders.

2026-10-11

medRxiv (prépublication)

Structural Remodeling of the Lumbar Spine Following Non-Surgical Spinal Decompression: An Automated MRI Study

Jacob A. Connolly

Nathan Molinier

Kenneth A. Weber

Julien Cohen‐Adad

Nathan D. Schilaty

Background and Objectives: To investigate MRI changes using SpineReport (r20260928) following non-surgical spinal decompression (NSSD) in pa… (voir plus)tients with chronic low back pain (cLBP). We conducted a retrospective review of patients treated with NSSD who obtained MRI within 6 months of treatment initiation. Methods: Thirty-six subjects (20 F, 16 M), with a mean age of 55.9 ± 16.4 years, were treated at the USF Health Chiropractic Clinic, Department of Neurosurgery, Brain & Spine. NSSD using DRX9000® (Excite Medical, Tampa, FL, USA) was utilized, with a median of 20 (20, 25) treatments. Treatment levels included L3 (n = 2), L4 (n = 18), and L5 (n = 16). Sagittal T2-weighted images were processed using TotalSpineSeg (r20251124) for automated segmentation, with SpineReport used to quantify disc, vertebrae, spinal canal, and intervertebral foramen metrics. Results: Mean pain scores improved by 3.4 ± 1.8 from 5.6 ± 1.6 (p 0.001), while Oswestry Disability Index scores improved by 10.8 ± 9.1 from 17.3 ± 8.0 (p 0.001). At the treated level, spinal canal cross-sectional area increased from 170.9 to 175.8 mm2 (2.9%, p = 0.040), and right–left diameter increased from 16.0 to 16.3 mm (1.9%, p = 0.025). Disc volume decreased from 7762.8 to 7449.5 mm3 (−4.0%, p = 0.046). No significant changes were observed in disc thickness, DHI, intervertebral foramen area, or vertebral measurements (p > 0.05). Conclusions: SpineReport enabled automated quantification of key spinal structures. NSSD was associated with increased spinal canal dimensions and improved symptoms. Further research is needed to determine the persistence and clinical significance of these structural changes.

2026-09-28

Journal of Functional Morphology and Kinesiology (publié)

An evolutionarily conserved interferon-responsive oligodendroglial state emerges during white matter aging

Pieter‐Jan Serneels

Julie D. De Schutter

Luca Masin

A. Collin

Fien Hermans

Julien Cohen‐Adad

Steven Bergmans

Lieve Moons

Abstract White matter dysfunction is a hallmark of brain aging and often precedes overt neurodegeneration, yet the cellular alterations conn… (voir plus)ecting aging to white matter dysfunction remain poorly understood. Here, we establish the killifish optic nerve as a translational model of white matter aging by integrating transcriptomic, histological and ultrastructural analyses. This tissue recapitulates key molecular and structural features of mammalian white matter aging, including the depletion of oligodendroglial progenitor cells, metabolic dysfunction and reduced myelin thickness. Intriguingly, aging is also associated with the emergence of an interferon-responsive oligodendroglial state. This state is characterized by interferon response and antigen presentation programs that closely resemble those of pathology-associated oligodendroglia described in murine models of central nervous system disease. Our findings identify oligodendroglial dysfunction as a central feature of white matter aging and suggest that this age-associated oligodendroglial state emerges before overt neurodegeneration, providing a potential cellular link between aging and neurodegenerative diseases.

2026-09-24

bioRxiv (prépublication)

Lessons learned from deploying imaging AI with the open PACS-AI platform

Samuel Kadoury

Julie G. Hussin

Pascal Theriault-Lauzier

Laurent Létourneau-Guillon

Rob Lewis

Adam McArthur

Gordon J. Harris

Houda Bahig

Pierre-Luc Deziel

Jay Kshirsagar

Jacob L. Jaremko

Jacques Delfrate

Robert Avram

We describe deploying imaging AI at six hospitals through PACS-AI, an open self-hosted platform. The binding constraint is not model accurac… (voir plus)y but infrastructure to route studies, display results, capture feedback, and audit what runs. At one center, angiography models completed 515 of 607 jobs (84.8%); failures reflected absent diagnostic views, and 78.1% of 638 clinician ratings were positive. Publishing honest readiness levels for every model is itself a governance practice.

2026-09-21

arXiv (prépublication)

arxiv.org

Normative Reference Values and Age-Related Variation in Advanced Diffusion MRI of the Pediatric Spinal Cord: DTI, DKI, and NODDI Metrics across Cervical and Thoracic Levels Using Hybrid Diffusion Imaging

Zahra Sadeghi Adl

Devon Middleton

Laura Krisa

Sara Naghizadehkashani

Mahdi Alizadeh

Slimane Tounekti

Scott H Faro

Adam Flanders

Jürgen Finsterbusch

Feroze B. Mohamed

BACKGROUND AND PURPOSE Normative diffusion values are essential for detecting microstructural abnormalities in the spinal cord. While diffus… (voir plus)ion kurtosis imaging (DKI) and neurite orientation dispersion and density imaging (NODDI) provide additional sensitivity beyond DTI, existing normative datasets are limited to adults with restricted cervical coverage. Pediatric spinal cord data remain scarce and predominantly DTI-based, leaving a gap in characterizing age-related microstructure. The purpose of this study was to establish a normative database of pediatric spinal cord diffusion metrics (DTI, DKI, NODDI) from C1-T12 using a clinically feasible Hybrid Diffusion Imaging (HYDI) protocol and to assess agreement between HYDI-derived and conventional DTI metrics. MATERIALS AND METHODS One hundred typically developing children (mean age 12.07 ± 3.09 years), aged 6-17 years, underwent a 3T MRI scan including a T2-weighted, multi-shell, multiband, HYDI (b=0, 800, 2000 s/mm2) sequence covering C1-T12 and a validation subset, a single-shell DTI sequence covering C2-C5. Ten microstructural metrics were quantified for white matter (WM), gray matter (GM), and whole cord at each vertebral level. Multivariable regression modeled age and sex. Agreement between HYDI-derived and conventional DTI at C3 was evaluated using paired t-tests, Pearson correlation, and Bland-Altman analysis. RESULTS Normative C1-T12 vertebral diffusion values were established. WM-GM contrast was evident for FA, NDI, MD, and AD, with significant differences across most cervical and thoracic segments. All metrics demonstrated significant age dependence (p .01) after adjustment for sex, with higher FA, kurtosis, ODI and NDI and lower diffusivity and fISO in older children. Sex effects were mod

2026-09-08

American Journal of Neuroradiology (publié)

Longitudinal tracking of multiple sclerosis lesions in the spinal cord: A validation study

Pierre-Louis Benveniste

Julian McGinnis

Shannon Kolind

Larry D. Lynd

Sarah A. Morrow

Jiwon Oh

Alexandre Prat

Alice Schabas

Penelope Smyth

Roger Tam

Anthony Traboulsee

Mark Mühlau

Hervé Lombaert

Longitudinal characterization of multiple sclerosis (MS) lesions remains constrained by the lack of frameworks capable of establishing consi… (voir plus)stent instance-level correspondences across time. Conventional segmentation approaches produce semantic lesion masks at each visit and therefore fail to capture the complex instance temporal patterns associated with lesion appearance, disappearance, splitting, or merging. This study presents a comparative evaluation of five strategies for automated tracking of spinal cord MS lesions in longitudinal MRI data from a multi-site cohort. The investigated strategies rely either on deformable registration or on a spinal anatomical reference system, and encompass overlap-based matching, coordinate-based Hungarian algorithm, gradient-boosted classification, and Siamese model classification. Tracking accuracy is quantified using instance-level true positives, false positives, and false negatives, allowing to assess the presence of one-to-many and many-to-one associations. Results show best performance for the registration-based overlap method. This study provides the first systematic analysis of lesion-instance correspondence in the spinal cord and outlines the strengths and limitations of registration-based and registration-free paradigms for longitudinal MS assessment. The code is available at http://github.com/ivadomed/longitudinal-sc-ms-lesion-tracking .

2026-09-07

arXiv (prépublication)

arxiv.org

1D Pre‐Acquisition Navigator Correcting Respiratory‐Induced Field Fluctuations in Multi‐Echo Gradient‐Echo Imaging of the Thoracic Spinal Cord

Alicia E. Cronin

Alexandre D’Astous

Nathan Williams

Antoine Guénette

Aimee Salakhov

Seth Stubblefield

Colin D. Mcknight

Lipika Narisetti

Subramaniam Sriram

Seth A. Smith

Ryan K. Robison

Guillaume Gilbert

Julien Cohen‐Adad

Kristin P. O’Grady

PURPOSE: In the spinal cord (SC), multi-echo gradient echo (ME-GRE) increases gray (GM) and white matter (WM) contrast and improves sensitiv… (voir plus)ity to lesions in people with multiple sclerosis (pwMS). However, SC ME-GRE is susceptible to breathing-induced field fluctuations, causing ghosting artifacts and signal loss. Recent work introduced a 1D phase navigator following the last echo to measure field variations; however, susceptibility to phase wrapping increases at longer echo times. We propose a 1D phase navigator preceding the first echo, reducing phase accumulation and eliminating the need for respiratory monitoring. METHODS: ME-GRE data covering the lower (T9-T12 vertebrae) and upper (T4-T8 vertebrae) thoracic SC were acquired in 20 healthy volunteers and 3 pwMS at 3T. Standard and navigator-corrected images were acquired in the same acquisition. To evaluate image quality, WM and GM signal-to-noise ratio (SNR), WM/GM contrast-to-noise ratio (CNR), and background ghosting signals were measured and compared between the two reconstructions. Both were blindly assessed for artifacts, structural delineation, and diagnostic confidence in pwMS. RESULTS: Navigator correction significantly increased GM and WM SNR and CNR, reduced posterior ghosting across both thoracic regions, and significantly reduced artifacts while increasing structural delineation. Preliminary evaluation in three pwMS showed consistent improvements in artifact mitigation, structural delineation, and lesion conspicuity with navigator correction, providing proof-of-concept for potential clinical application. CONCLUSION: A 1D navigator prior to the first echo reduces ghosting and improves thoracic SC image quality without respiratory monitoring. This approach could improve the diagnostic value and enhance the reliability of thoracic SC ME-GRE.

2026-07-23

Magnetic Resonance in Medicine (publié)

Patterns of Muscle Health in Single- and Multi-Site Chronic Pain: A UK Biobank Normative Modeling Study

Merve Kaptan

Yiyu Wang

Augustijn de Boer

Ananya Goyal

Skylar Holmes

Kerem Ozkan

Sandrine Bédard

Teresa Indriolo

Christine S W Law

Dario Pfyffer

Joel Fundaun

Estifanos Berhe

Garry E. Gold

Akshay Chaudhari

Anoosha Pai S

Anthony A. Gatti

Feliks Kogan

Brian A. Hargreaves

Scott L. Delp

John Ratliff … (voir 21 de plus)

Serena Hu

Anand Veeravagu

Atman Desai

Suzanne Tharin

Todd Alamin

Andrew C. Smith

Marnee J. McKay

Brian Kim

Robert Walsh

Alec Schielke

Dean Dennis

Johannes Decker

Benjamin De Leener

Zachary A. Smith

Fauziyya Muhammad

James M. Elliott

Andre F. Marquand

Sean Mackey

Evert Onno Wesselink

Kenneth A. Weber II

Abstract Background Chronic pain is associated with impaired muscle health, but whether these changes reflect site-specific factors, broader… (voir plus) systemic factors, or both remains unclear. The purpose of this study is to determine whether normative markers of muscle health derived from MRI show site-specific patterns in chronic pain. Methods UK Biobank participants who underwent whole-body MRI from 2006 to 2010 were included in this retrospective cross-sectional study. The MuscleMap Toolbox quantified volume and intramuscular fat (IMF) in 42 muscles of the abdomen, pelvis, and thigh. Normative models trained on a no pain group generated muscle-specific deviations from normal (i.e., Z-scores) for single- and multi-site chronic and acute pain. Results Of 17,843 participants, the primary site-specific analysis included 9,704 no pain, 885 single-site chronic back pain (CBP), 438 single-site chronic hip pain (CHP), and 1,315 single-site chronic knee pain (CKP) participants (n=12,342; mean age 63.7±7.5 years; 52.7% female). Additional analyses included single-site chronic neck/shoulder pain, acute pain, and multi-site chronic pain groups. In CBP, deviations were localized to abdominal muscles, with decreased volume in 6/8 and increased IMF in 6/8. In CHP, deviations were broad, with decreased volume in 3/8 of the abdominal and 14/26 of the thigh muscles, and increased IMF in 6/8 of the abdominal, 5/8 of the pelvic, and 4/26 of the thigh muscles. In CKP, deviations were localized to thigh muscles, with decreased volume in 8/26 and increased IMF in 6/26. Acute pain groups showed no significant differences except for decreased volume in one thigh muscle in acute knee pain. With each additional chronic pain site, volume decreased (β=−.078;IQR:−0.100−0.051), and IMF increased (β=.085;IQR:0.066−0.101). Combined Z-scores classified chronic pain groups better than chance (accuracy: 48.6%;p<.001), but not acute pain groups (accuracy: 39.0%;p=.20). Conclusions Whole-body MRI combined with AI-driven muscle segmentation and normative modeling revealed site-specific patterns of muscle health in single-site chronic pain.

2026-06-21

medRxiv (prépublication)

Charting Cervical Spinal Cord Morphometry Across the Lifespan

Kurt Schilling

Michael E Kim

Matthew Amandola

Chenyu Gao

Karthik Ramadass

Praitayini Kanakaraj

Sam Bogdanov

G Rudravaram

Nancy R. Newlin

Derek B. Archer

Timothy J Hohman

Angela L Jefferson

Victoria L Morgan

Alexandra Roche

Dario J Englot

Murat Bilgel

Lori L Beason-Held

Luigi Ferrucci

Laurie Cutting

Laura A Barquero … (voir 21 de plus)

Micah D’Archangel

Tin Q Nguyen

Kathryn L Humphreys

Yanbin Niu

Sophia Vinci-Booher

Carissa J. Cascio

Zhiyuan Li

Daniel Moyer

Simon Vandekar

Panpan Zhang

Samuelle St-Onge

Sandrine Bédard

Jan Valosek

Benjamin De Leener

John C Gore

Seth Smith

B A Landman

John C. Gore

Seth Smith

Bennett A. Landman

Abstract Spinal cord morphometry provides essential biomarkers of neurological health, but clinical interpretations are confounded by inter-… (voir plus)subject variability and a lack of normative references across the full human lifespan. We address this gap by generating the first comprehensive lifespan charts for cervical spinal cord morphometry. We leveraged 30 population-based brain MRI datasets, aggregating 78,269 scans from 41,042 individuals (ages 0–100) whose imaging protocols included cervical cord coverage. To overcome contrast variability, we employed a state-of-the-art contrast-agnostic deep learning segmentation method, extracting cross-sectional area (CSA), anteroposterior (AP) and right–left (RL/transverse), and shape indices (compression ratio, eccentricity, and solidity) from C1 to C7. Normative trajectories were modeled using Generalized Additive Models for Location, Scale, and Shape (GAMLSS). The resulting charts reveal distinct non-linear lifespan changes: rapid growth through childhood and adolescence, peak maturation occurring in early-to-mid adulthood (e.g., mid-30s for CSA), followed by gradual decreases. Significant regional variations along the cervical cord and consistent sex differences (males > females for size metrics) were quantified. Spinal cord trajectories showed strong temporal coupling with brain white matter and brainstem volumes, suggesting integrated CNS development and aging. These lifespan charts provide a robust normative framework, enabling age- and sex-specific centile scoring of individual spinal cord morphometry. This resource offers a critical tool for differentiating typical variation from pathological changes, enhancing the clinical utility of spinal cord MRI in studies of development and neurodegeneration.

2026-06-07

bioRxiv (accepté)

SpineReport: Automated 3D Quantification and Reporting of Lumbar Spine Degeneration on MRI

Nathan Molinier

Adrian A. Marth

Reto Sutter

Christoph Germann

Jacob A. Connolly

Mathieu Guay-Paquet

Nathan D. Schilaty

Kenneth A. Weber II

Lumbar spine conditions are a leading cause of disability worldwide, yet reliable quantification of degeneration from MRI remains challengin… (voir plus)g. In clinical practice, analysis is predominantly performed in two dimensions (2D), as manual three-dimensional (3D) assessment is time-consuming. However, 2D measurements suffer from limited reproducibility, particularly when anatomical structures are not aligned with the imaging plane. Existing automated approaches are often restricted to 2D, rely on discrete grading, or lack robustness and interpretability. We introduce SpineReport, an open-source, fully automated framework for comprehensive 3D morphometric analysis of lumbar spine MRI. Leveraging robust anatomical segmentations, the method extracts quantitative metrics from key structures, including the spinal canal, spinal cord, vertebrae, intervertebral discs, and foramina. These include both morphological and signal-based features, enabling cross-subject and longitudinal assessment. SpineReport further generates subject-specific reports that allow comparison with cohort distributions, improving interpretability and objective characterization of spinal morphology. Clinical relevance was evaluated against radiologist-reported severity grades for central canal, lateral recess, and foraminal stenosis. Metrics showed strong associations with central canal stenosis severity, with T2-weighted CSF signal providing the highest performance (AUC = 0.95). Canal AP diameter and area ratios also demonstrated strong correlations and high discriminative ability (AUC>0.80). For lateral recess stenosis, associations were moderate, with lateral CSF signal being the most informative (AUC = 0.73). No significant associations were observed for foraminal stenosis despite robust region-of-interest extraction. SpineReport is released as an open-access tool: https://ivadomed.github.io/SpineReport/

2026-06-07

arXiv (prépublication)

arxiv.org

Automated robust segmentation of the spinal canal on MRI

Abel Salmona

Sandrine Bédard

Jan Valosek

Kalum Ost

Maxime Bouthillier

Gergely David

Maryam Seif

Armin Curt

Nikolai Pfender

Markus Hupp

Patrick Freund

Tomáš Horák

Petr Kudlička

Josef Bednařík

Fauziyya Muhammad

Zachary A. Smith

2026-05-31

European Journal of Radiology Artificial Intelligence (publié)

Spinal cord imaging for multiple sclerosis: Advances, priorities, and opportunities

Cornelia Laule

Atlee A Witt

Gabriele C De Luca

Cristina Granziera

B Mark Keegan

Anne Kerbrat

Eric C Klawiter

Shannon Kolind

Kristin P O’Grady

Jiwon Oh

Kurt G Schilling

Dinesh K Sivakolundu

Seth A Smith

Ceren Tozlu

Irene M Vavasour

Francesca Bagnato

Susan A Gauthier

Caterina Mainero

Eva Alonso-Ortiz … (voir 9 de plus)

Rohit Bakshi

Erin S Beck

Matthew R Brier

Christopher C Hemond

Stephen Krieger

David KB Li

Russell T Shinohara

Roland G Henry

North American Imaging in Multiple Sclerosis (NAIMS) Cooperative

The spinal cord plays a central role in the pathophysiology and clinical manifestations of multiple sclerosis (MS), yet remains under-studie… (voir plus)d compared with the brain. This review summarizes key insights from the 2025 North American Imaging in MS Spinal Cord Imaging Workshop, highlighting recent advances, ongoing challenges, and future opportunities in MS spinal cord imaging. We review pathological studies and outline the clinical relevance of spinal cord lesions and atrophy for diagnosis, prognosis, and disease monitoring, highlighting emerging biomarkers of progression independent of relapse activity. Correlations between magnetic resonance imaging, histopathology, and clinical outcomes support the validation and translational potential of advanced spinal cord imaging techniques. Finally, we discuss spinal cord–specific processing pipelines and reproducibility challenges. Collectively, these insights underscore the need to integrate advanced and quantitative spinal cord imaging into clinical trials, research studies, and—when feasible—clinical care, to fully capture the extent of MS pathology, and ultimately improve patient outcomes.

2026-05-31

Multiple Sclerosis Journal (publié)