Shape Analysis of the Corpus Callosum in Alzheimer's Disease and Frontotemporal Lobar Degeneration Subtypes

Article type: Research Article

Authors: Walterfang, Mark^{a; *} | Luders, Eileen^b | Looi, Jeffrey C.L.^{c; d} | Rajagopalan, Priya^b | Velakoulis, Dennis^a | Thompson, Paul M.^{b; g; h} | Lindberg, Olof^d | Östberg, Per^e | Nordin, Love E.^f | Svensson, Leif^f | Wahlund, Lars-Olof^d

Affiliations: [a] Neuropsychiatry Unit, Royal Melbourne Hospital and Melbourne Neuropsychiatry Centre, University of Melbourne and Melbourne Health, Melbourne, Australia | [b] Laboratory of Neuro Imaging, Department of Neurology, UCLA School of Medicine, Los Angeles, CA, USA | [c] Research Centre for Neurosciences of Ageing, Academic Unit of Psychiatry and Addiction Medicine, Australian National University Medical School, Canberra, Australia | [d] Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institute, Stockholm, Sweden | [e] Division of Speech-Language Pathology, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, and Department of Speech-Language Pathology, Karolinska University Hospital, Stockholm, Sweden | [f] Hospital Physics, Karolinska University Hospital, Hospital Physics and Radiology, Huddinge, Stockholm, Sweden | [g] Department of Neurology, Psychiatry, Radiology, Pediatrics, Engineering & Ophthalmology, University of Southern California, Los Angeles, CA, USA | [h] USC Imaging Genetics Center, Marina del Rey, CA, USA

Correspondence: [*] Correspondence to: Mark Walterfang, Level 2, John Cade Building, Royal Melbourne Hospital 3050, Australia. Tel.: +61 3934 28750; Fax: +61 393428483; E-mail: mark.walterfang@mh.org.au.

Abstract: Morphology of the corpus callosum is a useful biomarker of neuronal loss, as different patterns of cortical atrophy help to distinguish between dementias such as Alzheimer's disease (AD) and frontotemporal lobar degeneration (FTLD). We used a sophisticated morphometric analysis of the corpus callosum in FTLD subtypes including frontotemporal dementia (FTD), semantic dementia (SD), and progressive non-fluent aphasia (PNFA), and compared them to AD patients and 27 matched controls. FTLD patient subgroups diverged in their callosal morphology profiles, with FTD patients showing marked widespread differences, PNFA patients with differences largely in the anterior half of the callosum, and SD patients differences in a small segment of the genu. AD patients showed differences in predominantly posterior callosal regions. This study is consistent with our previous findings showing significant cortical and subcortical regional atrophy across FTLD subtypes, and suggests that callosal atrophy patterns differentiate AD from FTLD, and FTLD subtypes.

Keywords: Alzheimer's disease, corpus callosum, frontotemporal dementia, white matter

DOI: 10.3233/JAD-131853

Journal: Journal of Alzheimer's Disease, vol. 40, no. 4, pp. 897-906, 2014