Academic Journal

Mitigating the Impact of MR Sequence Parameters: Increasing the Robustness of DL-Based Cortical Thickness Estimates.

Bibliographic Details
Title: Mitigating the Impact of MR Sequence Parameters: Increasing the Robustness of DL-Based Cortical Thickness Estimates.
Authors: Blattner T; Support Center for Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Inselspital, Bern University Hospital, Bern, Switzerland., Romascano D; Support Center for Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Inselspital, Bern University Hospital, Bern, Switzerland., McKinley R; Support Center for Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Inselspital, Bern University Hospital, Bern, Switzerland., Rebsamen M; Support Center for Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Inselspital, Bern University Hospital, Bern, Switzerland.; Balgrist University Hospital, Zurich, Switzerland., Salmen A; Department of Neurology, Inselspital, Bern University Hospital and University of Bern, Bern, Switzerland., Pistor M; Department of Neurology, Inselspital, Bern University Hospital and University of Bern, Bern, Switzerland., Hoepner R; Department of Neurology, Inselspital, Bern University Hospital and University of Bern, Bern, Switzerland., Wiest R; Support Center for Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Inselspital, Bern University Hospital, Bern, Switzerland.; Translational Imaging Center (TIC), Swiss Institute for Translational and Entrepreneurial Medicine, Sitem-Insel, Bern, Switzerland., Radojewski P; Support Center for Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Inselspital, Bern University Hospital, Bern, Switzerland.; Translational Imaging Center (TIC), Swiss Institute for Translational and Entrepreneurial Medicine, Sitem-Insel, Bern, Switzerland., Rummel C; Support Center for Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Inselspital, Bern University Hospital, Bern, Switzerland.; European Campus Rottal-Inn, Technische Hochschule Deggendorf, Pfarrkirchen, Germany., Capiglioni M; Support Center for Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, University of Bern, Inselspital, Bern University Hospital, Bern, Switzerland.; High-Field MR Center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany.
Source: Human brain mapping [Hum Brain Mapp] 2026 Jun 01; Vol. 47 (8), pp. e70560.
Publication Type: Journal Article
Language: English
Journal Info: Publisher: Wiley Country of Publication: United States NLM ID: 9419065 Publication Model: Print Cited Medium: Internet ISSN: 1097-0193 (Electronic) Linking ISSN: 10659471 NLM ISO Abbreviation: Hum Brain Mapp Subsets: MEDLINE
Imprint Name(s): Publication: New York : Wiley
Original Publication: New York : Wiley-Liss, c1993-
MeSH Terms: Magnetic Resonance Imaging*/methods , Magnetic Resonance Imaging*/standards , Cerebral Cortex*/diagnostic imaging , Cerebral Cortex*/pathology , Multiple Sclerosis, Relapsing-Remitting*/diagnostic imaging , Multiple Sclerosis, Relapsing-Remitting*/pathology , Image Processing, Computer-Assisted*/methods , Image Processing, Computer-Assisted*/standards , Neuroimaging*/methods , Neuroimaging*/standards , Deep Learning* , Brain Cortical Thickness*, Atrophy/pathology ; Humans ; Female ; Male ; Adult ; Middle Aged
Abstract: Cortical thickness measurements from MRI are increasingly used as biomarkers for neurodegenerative disease progression. However, variations in MRI acquisition parameters, such as inversion time (TI) and repetition time (TR), which are common in clinical settings, can compromise the reliability and sensitivity of these measurements. We fine-tuned a deep-learning-based segmentation tool (DL+DiReCT) to reduce its dependence to image contrast variations by training it on simulated MPRAGE images derived from quantitative relaxation maps. Fine-tuning markedly reduced contrast sensitivity, with the Pearson correlation coefficient decreasing from INLINEMATH to INLINEMATH . Evaluation on a synthetic atrophy dataset demonstrated that our model accurately replicated atrophy trends with minimal underestimation, outperforming FreeSurfer and SynthSeg. When applied to a dataset of relapsing-remitting multiple sclerosis (RRMS) patients, the fine-tuned model showed a substantial reduction in contrast sensitivity and maintained stable performance after controlling for covariates such as age, sex, field strength, and Expanded Disability Status Scale (EDSS) score. Overall, the proposed approach achieves robust contrast invariance without sacrificing sensitivity to cortical atrophy, offering a practical improvement for longitudinal and multi-center clinical studies.
(© 2026 The Author(s). Human Brain Mapping published by Wiley Periodicals LLC.)
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Grant Information: 204593 United Kingdom WT_ Wellcome Trust
Contributed Indexing: Keywords: MR; brain morphometry; contrast; cortical thickness; deep learning; multiple sclerosis; robustness
Entry Date(s): Date Created: 20260608 Date Completed: 20260612 Latest Revision: 20260726
Update Code: 20260726
PubMed Central ID: PMC13243191
DOI: 10.1002/hbm.70560
PMID: 42252567
Database: MEDLINE
Description
ISSN:1097-0193
DOI:10.1002/hbm.70560