doi: 10.3174/ajnr.A1640
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
American Journal of Neuroradiology 30:1552-1560, September 2009
© 2009 American Society of Neuroradiology
BRAIN
Putaminal Volume in Frontotemporal Lobar Degeneration and Alzheimer Disease: Differential Volumes in Dementia Subtypes and Controls
From the Academic Unit of Psychological Medicine (J.C.L.L.), Research Centre for the Neurosciences of Ageing, Australian National University Medical School, Canberra Hospital, Canberra, Australia
Department of Neurobiology (J.C.L.L., O.L., B.B.Z., P.Ö., L.-O.W.), Karolinska Institute, Caring Sciences and Society, Division of Clinical Geriatrics, Huddinge, Stockholm, Sweden
Hospital Physics and Radiology (L.S., E.Ö.), Karolinska University Hospital, Huddinge, Stockholm, Sweden. Dr Zandbelt is now with Rudolf Magnus Institute of Neuroscience, Department of Psychiatry, University Medical Center Utrecht, the Netherlands. Dr. Östberg is now with the Department of Neuroscience, Uppsala University, Uppsala, Sweden.
Please address correspondence to Jeffrey Looi, MD, Research Centre for the Neurosciences of Ageing, Academic Unit of Psychological Medicine, Australian National University Medical School, Building 4, Level 2, The Canberra Hospital, PO Box 11, Woden ACT 2605, Australia; e-mail: Jeffrey.looi{at}anu.edu.au
BACKGROUND AND PURPOSE: Frontostriatal (including the putamen) circuit–mediated cognitive dysfunction has been implicated in frontotemporal lobar degeneration (FTLD), but not in Alzheimer disease (AD) or healthy aging. We sought to assess putaminal volume as a measure of the structural basis of relative frontostriatal dysfunction in these groups.
MATERIALS AND METHODS: We measured putaminal volume in FTLD subtypes: frontotemporal dementia (FTD, n = 12), semantic dementia (SD, n = 13), and progressive nonfluent aphasia (PNFA, n = 9) in comparison with healthy controls (n = 25) and patients with AD (n = 18). Diagnoses were based on accepted clinical criteria. We conducted manual volume measurement of the putamen blinded to the diagnosis on T1 brain MR imaging by using a standardized protocol.
RESULTS: Paired t tests (P < .05) showed that the left putaminal volume was significantly larger than the right in all groups combined. Multivariate analysis of covariance with a Bonferroni correction was used to assess statistical significance among the subject groups (AD, FTD, SD, PNFA, and controls) as independent variables and right/left putaminal volumes as dependent variables (covariates, age and intracranial volume; P < .05). The right putamen in FTD was significantly smaller than in AD and controls; whereas in SD, it was smaller compared with controls with a trend toward being smaller than in AD. There was also a trend toward the putamen in the PNFA being smaller than that in controls and in patients with AD. Across the groups, there was a positive partial correlation between putaminal volume and Mini-Mental State Examination (MMSE).
CONCLUSIONS: Right putaminal volume was significantly smaller in FTD, the FTLD subtype with the greatest expected frontostriatal dysfunction; whereas in SD and PNFA, it showed a trend towards being smaller, consistent with expectation, compared to controls and AD; and in SD, compared with AD and controls. Putaminal volume weakly correlated with MMSE.