Alzheimer's disease (AD) and executive dysfunction. A case-control study on the significance of frontal white matter changes detected by diffusion tensor imaging (DTI).
White matter (WM) changes are frequently seen on structural imaging in AD but the clinical relevance of these changes is uncertain. Frontal WM pathology is often observed upon neuropathological examination in AD. Since frontal cortical/sub-cortical pathology is known to relate to executive dysfunction, the aim was to elucidate if frontal WM changes in AD correlated with executive dysfunction. In all, 15 AD patients and 15 age-matched control cases were investigated in the study, which covered conventional magnetic resonance imaging (MRI), DTI, neuropsychiatric and neuropsychological examinations. Reduced performance on neuropsychological testing of executive function correlated significantly with an increasing degree of frontal WM changes detected by DTI in the AD group, while no such correlation was observed for the controls. Conventional semi-quantitative MRI assessment did not correlate with results on neuropsychological testing of executive function in any of the groups. The structural correlate to certain dimensions of executive dysfunction in AD patients could be related to changes in the deep frontal WM. DTI appears to be more sensitive in the detection of clinically significant WM alterations than conventional semi-quantitative MRI.
Department of Psychogeriatrics, University Hospital, and Department of Medical Radiation Physics, Lund University, Klinikgatan 22, SE-221 85 Lund, Sweden. Martin_Sjobeck@med.lu.se
Martin
M
Sjöbeck
Christina
C
Elfgren
Elna-Marie
EM
Larsson
Sara
S
Brockstedt
Jimmy
J
Lätt
Elisabet
E
Englund
Ulla
U
Passant
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000473:pathology*; D016022:Case-Control Studies; D056324:Diffusion Tensor Imaging; D056344:Executive Function; D005260:Female; D005625:Frontal Lobe / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D016555:Matched-Pair Analysis; D009483:Neuropsychological Tests; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric