Variability and reproducibility of multi-echo T2 relaxometry: Insights from multi-site, multi-session and multi-subject MRI acquisitions

Quantitative magnetic resonance imaging (qMRI) can increase the specificity and sensitivity of conventional weighted MRI to underlying pathology by comparing meaningful physical or chemical parameters, measured in physical units, with normative values acquired in a healthy population. This study foc...

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Main Authors: Elda Fischi-Gomez, Gabriel Girard, Philipp J. Koch, Thomas Yu, Marco Pizzolato, Julia Brügger, Gian Franco Piredda, Tom Hilbert, Andéol G. Cadic-Melchior, Elena Beanato, Chang-Hyun Park, Takuya Morishita, Maximilian J. Wessel, Simona Schiavi, Alessandro Daducci, Tobias Kober, Erick J. Canales-Rodríguez, Friedhelm C. Hummel, Jean-Philippe Thiran
Format: Article
Language:English
Published: Frontiers Media S.A. 2022-07-01
Series:Frontiers in Radiology
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/fradi.2022.930666/full
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author Elda Fischi-Gomez
Elda Fischi-Gomez
Gabriel Girard
Gabriel Girard
Gabriel Girard
Philipp J. Koch
Philipp J. Koch
Philipp J. Koch
Philipp J. Koch
Thomas Yu
Thomas Yu
Marco Pizzolato
Marco Pizzolato
Julia Brügger
Julia Brügger
Gian Franco Piredda
Gian Franco Piredda
Gian Franco Piredda
Tom Hilbert
Tom Hilbert
Tom Hilbert
Andéol G. Cadic-Melchior
Andéol G. Cadic-Melchior
Elena Beanato
Elena Beanato
Chang-Hyun Park
Chang-Hyun Park
Takuya Morishita
Takuya Morishita
Maximilian J. Wessel
Maximilian J. Wessel
Maximilian J. Wessel
Simona Schiavi
Simona Schiavi
Alessandro Daducci
Tobias Kober
Tobias Kober
Tobias Kober
Erick J. Canales-Rodríguez
Friedhelm C. Hummel
Friedhelm C. Hummel
Friedhelm C. Hummel
Jean-Philippe Thiran
Jean-Philippe Thiran
Jean-Philippe Thiran
author_facet Elda Fischi-Gomez
Elda Fischi-Gomez
Gabriel Girard
Gabriel Girard
Gabriel Girard
Philipp J. Koch
Philipp J. Koch
Philipp J. Koch
Philipp J. Koch
Thomas Yu
Thomas Yu
Marco Pizzolato
Marco Pizzolato
Julia Brügger
Julia Brügger
Gian Franco Piredda
Gian Franco Piredda
Gian Franco Piredda
Tom Hilbert
Tom Hilbert
Tom Hilbert
Andéol G. Cadic-Melchior
Andéol G. Cadic-Melchior
Elena Beanato
Elena Beanato
Chang-Hyun Park
Chang-Hyun Park
Takuya Morishita
Takuya Morishita
Maximilian J. Wessel
Maximilian J. Wessel
Maximilian J. Wessel
Simona Schiavi
Simona Schiavi
Alessandro Daducci
Tobias Kober
Tobias Kober
Tobias Kober
Erick J. Canales-Rodríguez
Friedhelm C. Hummel
Friedhelm C. Hummel
Friedhelm C. Hummel
Jean-Philippe Thiran
Jean-Philippe Thiran
Jean-Philippe Thiran
author_sort Elda Fischi-Gomez
collection DOAJ
description Quantitative magnetic resonance imaging (qMRI) can increase the specificity and sensitivity of conventional weighted MRI to underlying pathology by comparing meaningful physical or chemical parameters, measured in physical units, with normative values acquired in a healthy population. This study focuses on multi-echo T2 relaxometry, a qMRI technique that probes the complex tissue microstructure by differentiating compartment-specific T2 relaxation times. However, estimation methods are still limited by their sensitivity to the underlying noise. Moreover, estimating the model's parameters is challenging because the resulting inverse problem is ill-posed, requiring advanced numerical regularization techniques. As a result, the estimates from distinct regularization strategies are different. In this work, we aimed to investigate the variability and reproducibility of different techniques for estimating the transverse relaxation time of the intra- and extra-cellular space (T2IE) in gray (GM) and white matter (WM) tissue in a clinical setting, using a multi-site, multi-session, and multi-run T2 relaxometry dataset. To this end, we evaluated three different techniques for estimating the T2 spectra (two regularized non-negative least squares methods and a machine learning approach). Two independent analyses were performed to study the effect of using raw and denoised data. For both the GM and WM regions, and the raw and denoised data, our results suggest that the principal source of variance is the inter-subject variability, showing a higher coefficient of variation (CoV) than those estimated for the inter-site, inter-session, and inter-run, respectively. For all reconstruction methods studied, the CoV ranged between 0.32 and 1.64%. Interestingly, the inter-session variability was close to the inter-scanner variability with no statistical differences, suggesting that T2IE is a robust parameter that could be employed in multi-site neuroimaging studies. Furthermore, the three tested methods showed consistent results and similar intra-class correlation (ICC), with values superior to 0.7 for most regions. Results from raw data were slightly more reproducible than those from denoised data. The regularized non-negative least squares method based on the L-curve technique produced the best results, with ICC values ranging from 0.72 to 0.92.
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spelling doaj.art-41959854d7144c888ba84bd844ce07512022-12-22T02:50:17ZengFrontiers Media S.A.Frontiers in Radiology2673-87402022-07-01210.3389/fradi.2022.930666930666Variability and reproducibility of multi-echo T2 relaxometry: Insights from multi-site, multi-session and multi-subject MRI acquisitionsElda Fischi-Gomez0Elda Fischi-Gomez1Gabriel Girard2Gabriel Girard3Gabriel Girard4Philipp J. Koch5Philipp J. Koch6Philipp J. Koch7Philipp J. Koch8Thomas Yu9Thomas Yu10Marco Pizzolato11Marco Pizzolato12Julia Brügger13Julia Brügger14Gian Franco Piredda15Gian Franco Piredda16Gian Franco Piredda17Tom Hilbert18Tom Hilbert19Tom Hilbert20Andéol G. Cadic-Melchior21Andéol G. Cadic-Melchior22Elena Beanato23Elena Beanato24Chang-Hyun Park25Chang-Hyun Park26Takuya Morishita27Takuya Morishita28Maximilian J. Wessel29Maximilian J. Wessel30Maximilian J. Wessel31Simona Schiavi32Simona Schiavi33Alessandro Daducci34Tobias Kober35Tobias Kober36Tobias Kober37Erick J. Canales-Rodríguez38Friedhelm C. Hummel39Friedhelm C. Hummel40Friedhelm C. Hummel41Jean-Philippe Thiran42Jean-Philippe Thiran43Jean-Philippe Thiran44Signal Processing Laboratory 5 (LTS5), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandTranslational Machine Learning Lab, Department of Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, SwitzerlandSignal Processing Laboratory 5 (LTS5), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandCIBM Center for Biomedical Imaging, Lausanne, SwitzerlandDepartment of Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, SwitzerlandDefitech Chair for Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandDefitech Chair of Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL Valais), Clinique Romande de Réadaptation, Sion, SwitzerlandDepartment of Neurology, University of Lübeck, Lübeck, GermanyCenter of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Lübeck, GermanySignal Processing Laboratory 5 (LTS5), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandAdvanced Clinical Imaging Technology, Siemens Healthineers International AG, Lausanne, SwitzerlandSignal Processing Laboratory 5 (LTS5), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland0Department of Applied Mathematics and Computer Science, Technical University of Denmark, Kongens Lyngby, DenmarkDefitech Chair for Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandDefitech Chair of Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL Valais), Clinique Romande de Réadaptation, Sion, SwitzerlandSignal Processing Laboratory 5 (LTS5), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandDepartment of Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, SwitzerlandAdvanced Clinical Imaging Technology, Siemens Healthineers International AG, Lausanne, SwitzerlandSignal Processing Laboratory 5 (LTS5), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandDepartment of Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, SwitzerlandAdvanced Clinical Imaging Technology, Siemens Healthineers International AG, Lausanne, SwitzerlandDefitech Chair for Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandDefitech Chair of Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL Valais), Clinique Romande de Réadaptation, Sion, SwitzerlandDefitech Chair for Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandDefitech Chair of Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL Valais), Clinique Romande de Réadaptation, Sion, SwitzerlandDefitech Chair for Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandDefitech Chair of Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL Valais), Clinique Romande de Réadaptation, Sion, SwitzerlandDefitech Chair for Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandDefitech Chair of Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL Valais), Clinique Romande de Réadaptation, Sion, SwitzerlandDefitech Chair for Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandDefitech Chair of Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL Valais), Clinique Romande de Réadaptation, Sion, Switzerland1Department of Neurology, University Hospital and Julius-Maximilians-University, Wuerzburg, Germany2Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DINOGMI), University of Genoa, Genoa, Italy3Diffusion Imaging and Connectivity Estimation (DICE) Lab, Department of Computer Science, University of Verona, Verona, Italy3Diffusion Imaging and Connectivity Estimation (DICE) Lab, Department of Computer Science, University of Verona, Verona, ItalySignal Processing Laboratory 5 (LTS5), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandDepartment of Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, SwitzerlandAdvanced Clinical Imaging Technology, Siemens Healthineers International AG, Lausanne, SwitzerlandSignal Processing Laboratory 5 (LTS5), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandDefitech Chair for Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandDefitech Chair of Clinical Neuroengineering, Neuro-X Institute (NIX) and Brain Mind Institute (BMI), École Polytechnique Fédérale de Lausanne (EPFL Valais), Clinique Romande de Réadaptation, Sion, Switzerland4Clinical Neuroscience, University Hospital of Geneva (HUG), Geneva, SwitzerlandSignal Processing Laboratory 5 (LTS5), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, SwitzerlandCIBM Center for Biomedical Imaging, Lausanne, SwitzerlandDepartment of Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, SwitzerlandQuantitative magnetic resonance imaging (qMRI) can increase the specificity and sensitivity of conventional weighted MRI to underlying pathology by comparing meaningful physical or chemical parameters, measured in physical units, with normative values acquired in a healthy population. This study focuses on multi-echo T2 relaxometry, a qMRI technique that probes the complex tissue microstructure by differentiating compartment-specific T2 relaxation times. However, estimation methods are still limited by their sensitivity to the underlying noise. Moreover, estimating the model's parameters is challenging because the resulting inverse problem is ill-posed, requiring advanced numerical regularization techniques. As a result, the estimates from distinct regularization strategies are different. In this work, we aimed to investigate the variability and reproducibility of different techniques for estimating the transverse relaxation time of the intra- and extra-cellular space (T2IE) in gray (GM) and white matter (WM) tissue in a clinical setting, using a multi-site, multi-session, and multi-run T2 relaxometry dataset. To this end, we evaluated three different techniques for estimating the T2 spectra (two regularized non-negative least squares methods and a machine learning approach). Two independent analyses were performed to study the effect of using raw and denoised data. For both the GM and WM regions, and the raw and denoised data, our results suggest that the principal source of variance is the inter-subject variability, showing a higher coefficient of variation (CoV) than those estimated for the inter-site, inter-session, and inter-run, respectively. For all reconstruction methods studied, the CoV ranged between 0.32 and 1.64%. Interestingly, the inter-session variability was close to the inter-scanner variability with no statistical differences, suggesting that T2IE is a robust parameter that could be employed in multi-site neuroimaging studies. Furthermore, the three tested methods showed consistent results and similar intra-class correlation (ICC), with values superior to 0.7 for most regions. Results from raw data were slightly more reproducible than those from denoised data. The regularized non-negative least squares method based on the L-curve technique produced the best results, with ICC values ranging from 0.72 to 0.92.https://www.frontiersin.org/articles/10.3389/fradi.2022.930666/fullrelaxometryreproducibilityvariabilityMRImulti-echoquantitative MRI
spellingShingle Elda Fischi-Gomez
Elda Fischi-Gomez
Gabriel Girard
Gabriel Girard
Gabriel Girard
Philipp J. Koch
Philipp J. Koch
Philipp J. Koch
Philipp J. Koch
Thomas Yu
Thomas Yu
Marco Pizzolato
Marco Pizzolato
Julia Brügger
Julia Brügger
Gian Franco Piredda
Gian Franco Piredda
Gian Franco Piredda
Tom Hilbert
Tom Hilbert
Tom Hilbert
Andéol G. Cadic-Melchior
Andéol G. Cadic-Melchior
Elena Beanato
Elena Beanato
Chang-Hyun Park
Chang-Hyun Park
Takuya Morishita
Takuya Morishita
Maximilian J. Wessel
Maximilian J. Wessel
Maximilian J. Wessel
Simona Schiavi
Simona Schiavi
Alessandro Daducci
Tobias Kober
Tobias Kober
Tobias Kober
Erick J. Canales-Rodríguez
Friedhelm C. Hummel
Friedhelm C. Hummel
Friedhelm C. Hummel
Jean-Philippe Thiran
Jean-Philippe Thiran
Jean-Philippe Thiran
Variability and reproducibility of multi-echo T2 relaxometry: Insights from multi-site, multi-session and multi-subject MRI acquisitions
Frontiers in Radiology
relaxometry
reproducibility
variability
MRI
multi-echo
quantitative MRI
title Variability and reproducibility of multi-echo T2 relaxometry: Insights from multi-site, multi-session and multi-subject MRI acquisitions
title_full Variability and reproducibility of multi-echo T2 relaxometry: Insights from multi-site, multi-session and multi-subject MRI acquisitions
title_fullStr Variability and reproducibility of multi-echo T2 relaxometry: Insights from multi-site, multi-session and multi-subject MRI acquisitions
title_full_unstemmed Variability and reproducibility of multi-echo T2 relaxometry: Insights from multi-site, multi-session and multi-subject MRI acquisitions
title_short Variability and reproducibility of multi-echo T2 relaxometry: Insights from multi-site, multi-session and multi-subject MRI acquisitions
title_sort variability and reproducibility of multi echo t2 relaxometry insights from multi site multi session and multi subject mri acquisitions
topic relaxometry
reproducibility
variability
MRI
multi-echo
quantitative MRI
url https://www.frontiersin.org/articles/10.3389/fradi.2022.930666/full
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