White matter microstructure alterations in frontotemporal dementia: Phenotype‐associated signatures and single‐subject interpretation. Issue 2 (24th January 2022)

• Record Type: Journal Article
• Authors: McKenna, Mary Clare; Tahedl, Marlene; Murad, Aizuri; Lope, Jasmin; Hardiman, Orla; Hutchinson, Siobhan; Bede, Peter
• Is Part Of: Brain and behavior. Volume 12:Issue 2(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-01-24
• Subjects: amyotrophic lateral sclerosis -- biomarker -- frontotemporal dementia -- MRI -- neuroimaging; Neurology -- Periodicals; Neurosciences -- Periodicals; Psychology -- Periodicals; Psychiatry -- Periodicals; 616.8005
• DOI: 10.1002/brb3.2500
• Languages: English
• ISSNs: 2162-3279

Abstract

Abstract: Background: Frontotemporal dementias (FTD) include a genetically heterogeneous group of conditions with distinctive molecular, radiological and clinical features. The majority of radiology studies in FTD compare FTD subgroups to healthy controls to describe phenotype‐ or genotype‐associated imaging signatures. While the characterization of group‐specific imaging traits is academically important, the priority of clinical imaging is the meaningful interpretation of individual datasets. Methods: To demonstrate the feasibility of single‐subject magnetic resonance imaging (MRI) interpretation, we have evaluated the white matter profile of 60 patients across the clinical spectrum of FTD. A z ‐score‐based approach was implemented, where the diffusivity metrics of individual patients were appraised with reference to demographically matched healthy controls. Fifty white matter tracts were systematically evaluated in each subject with reference to normative data. Results: The z ‐score‐based approach successfully detected white matter pathology in single subjects, and group‐level inferences were analogous to the outputs of standard track‐based spatial statistics. Conclusions: Our findings suggest that it is possible to meaningfully evaluate the diffusion profile of single FTD patients if large normative datasets are available. In contrast to the visual review of FLAIR and T2‐weighted images, computational imaging offers objective, quantitative insights into white matter integrity changes even at single‐subject level. Abstract : While the characterization of group‐specific imaging traits is academically important, the priority of clinical imaging is the meaningful interpretation of individual datasets. In this study, a z ‐score‐based approach was implemented, where the diffusivity metrics of individual patients were appraised with reference to demographically matched healthy controls.