Portrait of Julien Cohen-Adad

Julien Cohen-Adad

Associate Academic Member
Associate Professor, Polytechnique Montréal, Electrical Engineering Department
Adjunct Professor, Université de Montréal, Department of Neuroscience
Research Topics
Medical Machine Learning

Biography

Julien Cohen-Adad is a professor at Polytechnique Montréal and the associate director of the Neuroimaging Functional Unit at Université de Montréal. He is also the Canada Research Chair in Quantitative Magnetic Resonance Imaging.

His research focuses on advancing neuroimaging methods with the help of AI. Some examples of projects are:

- Multi-modal training for medical imaging tasks (segmentation of pathologies, diagnosis, etc.)

- Adding prior from MRI physics to improve model generalization

- Incorporating uncertainty measures to deal with inter-rater variability

- Continuous learning strategies when data sharing is restricted

- Bringing AI methods into clinical radiology routine via user-friendly software solutions

Cohen-Adad also leads multiple open-source software projects that are benefiting the research and clinical community (see neuro.polymtl.ca/software.html). In short, he loves MRI with strong magnets, neuroimaging, programming and open science!

Current Students

Research Intern - Polytechnique Montréal
PhD - Polytechnique Montréal
Co-supervisor :
PhD - Polytechnique Montréal
Master's Research - Polytechnique Montréal
PhD - Polytechnique Montréal
Co-supervisor :
Master's Research - Polytechnique Montréal
Master's Research - Polytechnique Montréal
Research Intern - Polytechnique Montréal
PhD - Polytechnique Montréal
PhD - Polytechnique Montréal
Collaborating researcher
Master's Research - Polytechnique Montréal

Publications

Automated robust segmentation of the spinal canal on MRI
Abel Salmona
Maxime Bouthillier
Gergely Dávid
Maryam Seif
Armin Curt
Nikolai Pfender
Markus Hupp
Patrick Freund
Tomáš Horák
Petr Kudlička
Josef Bednařík
Fauziyya Muhammad
Zachary A. Smith
Monitoring morphometric drift in lifelong learning segmentation of the spinal cord.
Enamundram Naga Karthik
Christoph Stefan Aigner
Elise Bannier
Josef Bednařík
Virginie Callot
Anna Combes
Armin Curt
Gergely Dávid
Falk Eippert
Lynn Farner
Michael G. Fehlings
Patrick Freund
Tobias Granberg
Cristina Granziera
RHSCIR Network Imaging Group
Ulrike Horn
Tomáš Horák
Suzanne Humphreys … (see 36 more)
Markus Hupp
Anne Kerbrat
Nawal Kinany
Shannon Kolind
Petr Kudlička
Anna Lebret
Lisa Eunyoung Lee
Cristina Granziera
Allan R. Martin
Govind Nair
Megan McGrath
Kristin P. O’Grady
Jiwon Oh
Russell Ouellette
Nikolai Pfender
Dario Pfyffer
Pierre‐François Pradat
Alexandre Prat
Alexandre Prat
Daniel S. Reich
Ilaria Ricchi
Naama Rotem‐Kohavi
Simon Schading-Sassenhausen
Maryam Seif
Andrew Smith
Seth A. Smith
Grace Sweeney
Roger Tam
Anthony Traboulsee
Constantina A. Treaba
Charidimos Tsagkas
Dimitri Van De Ville
Zachary Vavasour
Kenneth A. Weber
Morphometric measures derived from spinal cord segmentations can serve as diagnostic and prognostic biomarkers in neurological diseases and … (see more)injuries affecting the spinal cord. For instance, the spinal cord cross-sectional area can be used to monitor cord atrophy in multiple sclerosis and to characterize compression in degenerative cervical myelopathy. While robust, automatic segmentation methods to a wide variety of contrasts and pathologies have been developed over the past few years, whether their predictions are stable as the model is updated using new datasets has not been assessed. This is particularly important for deriving normative values from healthy participants. In this study, we present a spinal cord segmentation model trained on a multisite (n=75) dataset, including 9 different MRI contrasts and several spinal cord pathologies. We also introduce a lifelong learning framework to automatically monitor the morphometric drift as the model is updated using additional datasets. The framework is triggered by an automatic GitHub Actions workflow every time a new model is created, recording the morphometric values derived from the model's predictions over time. As a real-world application of the proposed framework, we employed the spinal cord segmentation model to update a recently-introduced normative database of healthy participants containing commonly used measures of spinal cord morphometry. Results showed that: (i) our model performs well compared to its previous versions and existing pathology-specific models on the lumbar spinal cord, images with severe compression, and in the presence of intramedullary lesions and/or atrophy achieving an average Dice score of 0.95 ± 0.03; (ii) the automatic workflow for monitoring morphometric drift provides a quick feedback loop for developing future segmentation models; and (iii) the scaling factor required to update the database of morphometric measures is nearly constant among slices across the given vertebral levels, showing minimum drift between the current and previous versions of the model monitored by the framework. The model is freely available in Spinal Cord Toolbox v7.0.
Diffusion tractography outside the brain: the road less travelled
Kurt G. Schilling
Irvin Teh
Richard Dortch
Ibrahim Ibrahim
Nian Wang
Bruce Damon
Rory L. Cochran
Alexander Leemans
Diffusion tractography is a powerful MRI technique for mapping fibrous tissue architecture, traditionally applied to the white matter of the… (see more) brain. This report surveys the growing application of tractography to anatomical structures outside the brain, a domain that presents both unique challenges and unique opportunities. We examine its use in the heart, spinal cord, peripheral nerves, brachial plexus, kidney, skeletal muscle, and prostate. For each region, we detail the necessary methodological adaptations for acquisition, modeling, and processing, and highlight the unique anatomical information that can be derived for research and clinical applications. While significant challenges remain - spanning technical hurdles like physiological motion and susceptibility artifacts, to biological complexities like lower anisotropy and the interpretation of streamline validity - tractography beyond the brain provides invaluable, non-invasive insights into tissue micro-organization, opening a new frontier for biomedical imaging.
Canadian Spine Society
Adeesya Gausper
Lindsay M Andras
Ken D. Illingworth
David L. Skaggs
Rachelle Imbeault
Justin Dufresne
Sylvain Deschênes
Marjolaine Roy-Beaudry
Jack Legler
Lee Benaroch
Olivia Serhan
Draydon Cheng
Debra Bartley
Patrick Thornley
Khaled Skaik
Genevieve Belanger
Alexandra Stratton
Coyle Matthew
Stephen P. Kingwell
Eve C. Tsai … (see 355 more)
Eugene K. Wai
Hannah Fonteyne
S. Hryniuk
Eric Parent
K. Stampe
Marie J Beaulieu
Monica Chan
Gloria Thevasagayam
Gabriela Marino-Merlo
Zaid Salaheen
A. Malvea
Leeor Yefet
Ali Moghaddamjou
Sam Molot-Toker
Eisha Christian
Jennifer L Quon
P. B. Dirks
James M. Drake
James T. Rutka
Abhaya V. Kulkarni
Reinhard Zeller
George M. Ibrahim
Julie Joncas
Soraya Barchi
Stefan Parent
Karim Aboelmagd
Archana Sivakuganandan
Amna Zulfiqar
Anne Murphy
Stanley Moll
Julia Sorbara
Brett Rocos
Mark Camp
Geoffrey K. Shumilak
Jalen Dansby
Andrew Chan-Tai-Kong
David E. Lebel
Daisy A Lu
Monique Clar
M. F. Al-Shakfa
Parham Rasoulinejad
Firoz Miyanji
Karim Kantar
Timothy P. Carey
Ravi Ghag
Brent Lanting
Zeeshan Sardar
Saumayajit Basu
Manish Gupta
Abdullah T. Eissa
So Kato
Lawrence G. Lenke
Kristen Jones
Saumyajit Basu
Michael P Kelly
Justin Smith
S. Strantzas
Yong Qiu
Ferran Pellise
A. Alanay
Nasir A. Quraishi
R. Gray
G. Yoshida
Amer Aziz
Jennyfer Paulla Galdino Chaves
Brian Hsu
Stone Sima
Bhisham Singh
Vinay Kulkarni
Ashish D. Diwan
Taryn Ludwig
Farbod Moghaddam
Mina Aminghafari
May Choi
Eliana Seider
Lauren Daunt
Vanessa Vashishth
Ali Ahmadi
P. Brzozowski
Asra Toobaie
Renan R. Fernandes
Anthony V. Perruccio
Amir Mishreky
Mark Alexander MacLean
Lisa Julien
Glenn Patriquin
Jason Leblanc
Ryan Greene
J. Alant
Sean Barry
R. Glennie
Sean D. Christie
Greg MacIntosh
Daniel P Smith
Erin Bigney
Jeffrey Hebert
Eden Richardson
Neil Manson
Edward Abraham
Abdullah Zein
Kyra Holt
Hannah Isaac
Jillian Kearney
Chris Small
Abdullah A.S.M. AlDuwaisan
V. Smith
Tara Whittaker
Denise Eckenswiller
Elias Soumbasis
Robert Tanguay
Celina Nahanni
Tiffany Lung
James J Young
Chloe N Cadieux
Jin Tong Du
Raja Rampersaud
Andrew Glennie
Cynthia Dunning
Emma Jones
William Oxner
Kaike Lobo
P. Łajczak
Cláudia Santos
Numa Rajab
Rafael Oliveira
Y. Silva
R. Barbosa
Aazad Abbas
Gurjovan Sahi
Michael B Johnson
Edward Buchel
Jay Toor
Ronit Kulkarni
Melanie Bertolino
Chase Walton
Gabriella Rivas
John Glaser
Charles Reitman
James Lawrence
Robert Ravinsky
Mohammed Ali Alvi
Avery B. Nathens
Eva Yuan
Yingshi He
Francois Mathieu
Michael C. Sklar
Samuel Yoon
Luke Reda
Hussain Shakil
S. Sadiqi
S. Muijs
Charlotte Dandurand
Marcel Dvorak
F. C. Oner
Vivian Huong Hoang Thien Le
Pascal Mputu Mputu
Francis Bernard
Yiorgos Alexandros Cavayas
H. Hong
D. Kurban
Tianyu Yang
Nader Fallah
Christiana L Cheng
Suzanne Humphreys
Vanessa K. Noonan
Dana El-mughayyar
Colleen O’Connell
Husain Shakil
Zixuan Hu
Christopher W. Smith
Hui M Ling
Zakariya M Khan
Ervin Sejdic
Errol Colak
Christopher Witiw
Maude Duguay
Juan David Cifuentes Hernandez
Jean-Marc Mac-Thiong
Antoine Dionne
Natan Bensoussan
Andréane Richard-Denis
Louis Carrier
Jocelyn Blanchard
Bernard LaRue
Ariane Paquette
Yan Gabriel Morais David Silva
Christopher Nielsen
Vaidehi Bhatt
Stephen J. Lewis
Y. Raja Rampersaud
Brent Rosenstein
Chanelle Montpetit
Nicolas Vaillancourt
Geoffrey Dover
Christina Weiss
Lee Ann Papula
Antonys Melek
Maryse Fortin
A. Fazlollahi
Uri Barak
Samira Kalhor
Joshua Hien Nguyen
Carlo Santaguida
Ruheksh Raj
Kyle Rogan
Allison Marchuk
Erin Barrett
Anand Masson
Brandy Pratt
Danielle Michaud
Kateryna Skyrda
Sierra Simms
Brandon Herrington
Fawaz Siddiqi
Kevin Gurr
Mathieu Chayer
P-J Arnoux
Jeremy Rawlinson
Olumide Aruwajoye
Carl-Eric Aubin
Hussein Samhat
K. Pedro
A. A. Pirshahid
Genevieve Gore
K. Filion
Oliver Lasry
Jordan J. Levett
Nathan Evanview
G. Mcintosh
Nadav Rinott
Mathieu Laflamme
Andy Liu
Alexander Tuchman
Christopher Mikhail
Vivien K. Chan
James McDonald
Julien Zaldivar
G. Lonjon
Matthieu Vassal
Alexandre Dhenin
Alexis Perez
Martin Dupuy
V. Challier
J. Castelain
S. Ghailane
Matthieu Campana
Jonathan Lebhar
Gilles Guerin
Nicolas Pellet
Yann Sabah
T. Chevillotte
A. Darnis
Joseph Cristini
F.X. Ferracci
J. Delambre
Steffen Queinnec
Alexandre Delmotte
Paulo Marinho
R. Gauthé
P. Hannequin
Vianney Gilard
Jean Meyblum
Alexis Perrin
Raphaël Pietton
Nicolas Lonjon
Antoine Gennari
Ahmed Essa
Michael Craig
W. Bradley Jacobs
Peter Lewkonia
Fred Nicholls
Michael Yang
Julien-Cohen Adad
Isaac Wangai
Andrew Nataraj
Osman Hojanepesov
Matthew Skarsgard
Nathan Evaniew
Jérôme Paquet
Perry Dhaliwal
Najmedden Attabib
Chris Bailey
Jefferson R. Wilson
Daniel Kurtz
P. Phan
Christopher Sun
Newton Cho
Abdul Al-Shawwa
Bradley W. Jacobs
Jacques Bouchard
Steven Casha
Stephan duPlessis
Alex Soroceanu
Ganesh Swamy
Kenneth C. Thomas
David W. Cadotte
Landon J Hansen
Stephen Yip
Nicolas Dea
Chetan Bettegowda
Laurence D. Rhines
Daniel M. Sciubba
James M. Schuster
Stefano Boriani
M. Clarke
Paul Arnold
Anne Versteeg
Michael H. Weber
R. de la Garza Ramos
John Shin
Markian Pahuta
A. Luzatti
A. Disch
A. Gasbarrini
Jorrit‐jan Verlaan
William G J Teixeira
Ilya Laufer
Á. Lazáry
Dean Chou
Z. Gokaslan
Addisu Mesfin
Tony Goldschlager
C. Netzer
J. O'Toole
Ori Barzilai
Norio Kawahara
Naresh Kumar
Jeremy J. Reynolds
Rory Goodwin
Jetan Badhiwala
A. Sahgal
Michael G. Fehlings
Alex Kiss
Donald A. Redelmeier
William Chu Kwan
Nikolaus Koegl
Charles G. Fisher
Raphaële Charest-Morin
Alexandra Rocha
Matthew Renaud
Jennifer C. Urquhart
Supriya Singh
Marco Pérez Caceres
Omer Ahmed
Véronique Freire
Jesse Shen
Fidaa Al-shakfa
Danielle Boule
Z. Wang
Christopher S. Lozano
Armaan Malhotra
Vishwathsen Karthikeyan
Building a library of acute traumatic spinal cord injury images across Canada: a retrospective cohort study protocol
Naama Rotem-Kohavi
Suzanne Humphreys
Vanessa K Noonan
Christiana L Cheng
Mathieu Guay-Paquet
Maxime Bouthillier
Enamundram Naga Karthik
Emma Lichtenstein
Nick Guenther
Naj Attabib
Michael Hardisty
Jetan Badhiwala
Jeremie Larouche
Markian Pahuta
Sean Christie
Michael G Fehlings
Daryl Fourney
Brian K Kwon … (see 6 more)
Jean Marc Mac-Thiong
Jérôme Paquet
Philippe Phan
Christopher Witiw
David W Cadotte
MRI is increasingly recognised as a valuable tool for assessing prognosis and predicting outcomes following traumatic spinal cord injury (SC… (see more)I). Several potential MRI biomarkers have been identified, but efforts are still needed to improve the accuracy and feasibility of these biomarkers in clinical practice. This study aims to build a national Canadian SCI imaging repository for storing and analysing imaging data for SCI, with the goal of improving SCI MRI biomarkers to predict outcomes and inform clinical management. As a substudy of the Rick Hansen SCI Registry (RHSCIR), this retrospective multisite study includes individuals who sustained a traumatic cervical SCI between 2015 and 2021, were previously enrolled in RHSCIR, and had MRI scans acquired within 72 hours of injury and before any surgical intervention. Individuals with a penetrating trauma and/or with any prior spine surgery are excluded. The study principal investigator and research associates, experienced with data curation and with the standardised format and specifications of the Brain Imaging Data Structure standard, guide the site’s curator on the steps to perform image deidentification and curation to create standardised datasets across all sites. These datasets are transferred to a Digital Research Alliance of Canada (‘the Alliance’) server designated for this project and concatenated to form the national Canadian SCI imaging repository (Neurogitea). We are using a semiautomated processing pipeline to quantify lesion morphology, together with additional imaging measures that are manually extracted from the images (for instance, the relative maximal spinal cord compression and the maximum canal compromise). Through linkage to RHSCIR clinical and epidemiological data already available on eligible participants, regression analysis is planned to predict neurological outcomes at discharge, including the American Spinal Injury Association Impairment Scale grade, upper and lower extremity motor and sensory scores. This protocol has been submitted by the participating sites to obtain ethics and institutional approvals prior to the study initiation at each site. All 12 sites across Canada have now obtained ethics and institutional approvals. Study results will be disseminated at local, national and international conferences and by journal publications.
RootletSeg: Deep learning method for spinal rootlets segmentation across MRI contrasts
Katerina Krejci
Jiri Chmelik
Sandrine B'edard
Falk Eippert
Ulrike Horn
Virginie Callot
Purpose: To develop a deep learning method for the automatic segmentation of spinal nerve rootlets on various MRI scans. Material and Method… (see more)s: This retrospective study included MRI scans from two open-access and one private dataset, consisting of 3D isotropic 3T TSE T2-weighted (T2w) and 7T MP2RAGE (T1-weighted [T1w] INV1 and INV2, and UNIT1) MRI scans. A deep learning model, RootletSeg, was developed to segment C2-T1 dorsal and ventral spinal rootlets. Training was performed on 76 scans and testing on 17 scans. The Dice score was used to compare the model performance with an existing open-source method. Spinal levels derived from RootletSeg segmentations were compared with vertebral levels defined by intervertebral discs using Bland-Altman analysis. Results: The RootletSeg model developed on 93 MRI scans from 50 healthy adults (mean age, 28.70 years
RootletSeg: Deep learning method for spinal rootlets segmentation across MRI contrasts
Katerina Krejci
Jiri Chmelik
Sandrine B'edard
Falk Eippert
Ulrike Horn
Virginie Callot
Purpose: To develop a deep learning method for the automatic segmentation of spinal nerve rootlets on various MRI scans. Material and Method… (see more)s: This retrospective study included MRI scans from two open-access and one private dataset, consisting of 3D isotropic 3T TSE T2-weighted (T2w) and 7T MP2RAGE (T1-weighted [T1w] INV1 and INV2, and UNIT1) MRI scans. A deep learning model, RootletSeg, was developed to segment C2-T1 dorsal and ventral spinal rootlets. Training was performed on 76 scans and testing on 17 scans. The Dice score was used to compare the model performance with an existing open-source method. Spinal levels derived from RootletSeg segmentations were compared with vertebral levels defined by intervertebral discs using Bland-Altman analysis. Results: The RootletSeg model developed on 93 MRI scans from 50 healthy adults (mean age, 28.70 years
EPISeg: Automated segmentation of the spinal cord on echo planar images using open-access multi-center data
Merve Kaptan
Alexandra Tinnermann
Ali Khatibi
Alice Dabbagh
Christian Büchel
Christian W. Kündig
Christine S. W. Law
Csw Law
Dario Pfyffer
David J. Lythgoe
Dimitra Tsivaka
Dimitri Van De Ville
Falk Eippert
Fauziyya Muhammad
Gary H. Glover
Gergely Dávid
Grace Haynes
Jan Haaker
Jonathan C. W. Brooks … (see 23 more)
Jürgen Finsterbusch
Katherine T. Martucci
Kimberly J. Hemmerling
Mahdi Mobarak-Abadi
Mark A. Hoggarth
Matthew A. Howard
Molly G. Bright
Nawal Kinany
Olivia S. Kowalczyk
Patrick Freund
Robert L. Barry
Sean Mackey
Shahabeddin Vahdat
Simon Schading
Stephen B. McMahon
Todd Parish
Véronique Marchand-Pauvert
Yufen Chen
Zachary A. Smith
KA Weber
Kenneth A. Weber
Benjamin De Leener
Functional magnetic resonance imaging (fMRI) of the spinal cord is relevant for studying sensation, movement, and autonomic function. Prepro… (see more)cessing of spinal cord fMRI data involves segmentation of the spinal cord on gradient-echo echo planar imaging (EPI) images. Current automated segmentation methods do not work well on these data, due to the low spatial resolution, susceptibility artifacts causing distortions and signal drop-out, ghosting, and motion-related artifacts. Consequently, this segmentation task demands a considerable amount of manual effort which takes time and is prone to user bias. In this work, we (i) gathered a multi-center dataset of spinal cord gradient-echo EPI with ground-truth segmentations and shared it on OpenNeuro https://openneuro.org/datasets/ds005143/versions/1.3.0, and (ii) developed a deep learning-based model, EPISeg, for the automatic segmentation of the spinal cord on gradient-echo EPI data. We observe a significant improvement in terms of segmentation quality compared to other available spinal cord segmentation models. Our model is resilient to different acquisition protocols as well as commonly observed artifacts in fMRI data. The training code is available at https://github.com/sct-pipeline/fmri-segmentation/, and the model has been integrated into the Spinal Cord Toolbox as a command-line tool.
EPISeg: Automated segmentation of the spinal cord on echo planar images using open-access multi-center data
Merve Kaptan
Alexandra Tinnermann
Ali Khatibi
Alice Dabbagh
Christian Büchel
Christian W. Kündig
Csw Law
Dario Pfyffer
David J. Lythgoe
Dimitra Tsivaka
Dimitri Van De Ville
Falk Eippert
Fauziyya Muhammad
Gary H. Glover
Gergely Dávid
Grace Haynes
Jan Haaker
Jonathan C. W. Brooks
Jürgen Finsterbusch … (see 21 more)
Katherine T. Martucci
Kimberly J. Hemmerling
Mahdi Mobarak-Abadi
Mark A. Hoggarth
Matthew A. Howard
Molly G. Bright
Nawal Kinany
Olivia S. Kowalczyk
Patrick Freund
Robert L. Barry
Sean Mackey
Shahabeddin Vahdat
Simon Schading
Stephen B. McMahon
Todd Parish
Véronique Marchand-Pauvert
Yufen Chen
Zachary A. Smith
Kenneth A. Weber
Benjamin De Leener
Abstract Functional magnetic resonance imaging (fMRI) of the spinal cord is relevant for studying sensation, movement, and autonomic functio… (see more)n. Preprocessing of spinal cord fMRI data involves segmentation of the spinal cord on gradient-echo echo planar imaging (EPI) images. Current automated segmentation methods do not work well on these data, due to the low spatial resolution, susceptibility artifacts causing distortions and signal drop-out, ghosting, and motion-related artifacts. Consequently, this segmentation task demands a considerable amount of manual effort which takes time and is prone to user bias. In this work, we (i) gathered a multi-center dataset of spinal cord gradient-echo EPI with ground-truth segmentations and shared it on OpenNeuro https://openneuro.org/datasets/ds005143/versions/1.3.1 and (ii) developed a deep learning-based model, EPISeg, for the automatic segmentation of the spinal cord on gradient-echo EPI data. We observe a significant improvement in terms of segmentation quality compared with other available spinal cord segmentation models. Our model is resilient to different acquisition protocols as well as commonly observed artifacts in fMRI data. The training code is available at https://github.com/sct-pipeline/fmri-segmentation/, and the model has been integrated into the Spinal Cord Toolbox as a command-line tool.
Rootlets-based registration to the PAM50 spinal cord template
Valeria Oliva
Kenneth A. Weber
Abstract Spinal cord functional MRI studies require precise localization of spinal levels for reliable voxel-wise group analyses. Traditiona… (see more)l template-based registration of the spinal cord uses intervertebral discs for alignment. However, substantial anatomical variability across individuals exists between vertebral and spinal levels. This study proposes a novel registration approach that leverages spinal nerve rootlets to improve alignment accuracy and reproducibility across individuals. We developed a registration method leveraging dorsal cervical rootlets segmentation and aligning them non-linearly with the PAM50 spinal cord template. Validation was performed on a multi-subject, multi-site dataset (n = 267, 44 sites) and a multi-subject dataset with various neck positions (n = 10, 3 sessions). We further validated the method on task-based functional MRI (n = 23) to compare group-level activation maps using rootlet-based registration to traditional disc-based methods. Rootlet-based registration showed superior alignment across individuals compared with the traditional disc-based method on n = 226 individuals, and on n = 176 individuals for morphological analyses. Notably, rootlet positions were more stable across neck positions. Group-level analysis of task-based functional MRI using rootlet-based registration increased Z scores and activation cluster size compared with disc-based registration (number of active voxels from 3292 to 7978). Rootlet-based registration enhances both inter- and intra-subject anatomical alignment and yields better spatial normalization for group-level fMRI analyses. Our findings highlight the potential of rootlet-based registration to improve the precision and reliability of spinal cord neuroimaging group analysis.
Cervical Spinal Cord Magnetization Transfer Ratio and Its Relationship With Clinical Outcomes in Multiple Sclerosis
Lisa Eunyoung Lee
Irene M. Vavasour
Melanie Guenette
Katherine Sawicka
Neda Rashidi‐Ranjbar
Nathan Churchill
Akash Chopra
Adelia Adelia
Pierre-Louis Benveniste
Anthony Traboulsee
Nathalie Arbour
Fabrizio Giuliani
Larry D. Lynd
Scott B. Patten
Alexandre Prat
Alice Schabas
Penelope Smyth
Roger Tam
Yunyan Zhang … (see 6 more)
Simon J. Graham
Mojgan Hodaie
Anthony Feinstein
Shannon Kolind
Tom A. Schweizer
Jiwon Oh
ABSTRACT Objective The cervical spinal cord (cSC) is highly relevant to clinical dysfunction in multiple sclerosis (MS) but remains understu… (see more)died using quantitative magnetic resonance imaging (MRI). We assessed magnetization transfer ratio (MTR), a semi‐quantitative MRI measure sensitive to MS‐related tissue microstructural changes, in the cSC and its relationship with clinical outcomes in radiologically isolated syndrome (RIS) and MS. Methods MTR data were acquired from 52 RIS, 201 relapsing–remitting MS (RRMS), 47 primary progressive MS (PPMS), and 43 control (CON) participants across four sites in the Canadian Prospective Cohort Study to Understand Progression in MS (CanProCo) using 3.0 T MRI systems. Mean MTR was compared between groups in whole cSC and sub‐regions between C2‐C4. Multiple linear regression was used to evaluate relationships between MTR and clinical outcomes, including the expanded disability status scale (EDSS), walking speed test (WST), and manual dexterity test (MDT). Results There were consistent group differences in MTR, which were most pronounced between PPMS and CON (−5.8% to −3.7%, p ≤ 0.01). In PPMS, lower MTR was associated with greater disability as measured by EDSS (β = −0.3 to −0.1, p ≤ 0.03), WST (β = −0.9 to −0.5, p ≤ 0.04), and MDT (β = −0.6 and − 0.5, p = 0.04). In RRMS, MTR was associated with only EDSS (β = −0.1, p ≤ 0.03). Interpretation In this large sample of RIS and MS, cSC MTR was lowest in PPMS, with associations between MTR and clinical outcomes in MS but not RIS. These findings suggest that MTR provides important information about the underlying tissue microstructural integrity of the cSC relevant to clinical disability in established MS.
Cervical Spinal Cord Magnetization Transfer Ratio and Its Relationship With Clinical Outcomes in Multiple Sclerosis
Lisa Eunyoung Lee
Irene M. Vavasour
Melanie Guenette
Katherine Sawicka
Neda Rashidi‐Ranjbar
Nathan Churchill
Akash Chopra
Adelia Adelia
Pierre-Louis Benveniste
Anthony Traboulsee
Nathalie Arbour
Fabrizio Giuliani
Larry D. Lynd
Scott B. Patten
Alexandre Prat
Alice Schabas
Penelope Smyth
Roger Tam
Yunyan Zhang … (see 6 more)
Simon J. Graham
Mojgan Hodaie
Anthony Feinstein
Shannon Kolind
Tom A. Schweizer
Jiwon Oh