Regional distribution of white matter hyperintensities in vascular dementia, Alzheimer's disease and healthy aging.
BACKGROUND
White matter hyperintensities (WMH) on MRI scans indicate lesions of the subcortical fiber system. The regional distribution of WMH may be related to their pathophysiology and clinical effect in vascular dementia (VaD), Alzheimer's disease (AD) and healthy aging.


METHODS
Regional WMH volumes were measured in MRI scans of 20 VaD patients, 25 AD patients and 22 healthy elderly subjects using FLAIR sequences and surface reconstructions from a three-dimensional MRI sequence.


RESULTS
The intraclass correlation coefficient for interrater reliability of WMH volume measurements ranged between 0.99 in the frontal and 0.72 in the occipital lobe. For each cerebral lobe, the WMH index, i.e. WMH volume divided by lobar volume, was highest in VaD and lowest in healthy controls. Within each group, the WMH index was higher in frontal and parietal lobes than in occipital and temporal lobes. Total WMH index and WMH indices in the frontal lobe correlated significantly with the MMSE score in VaD. Category fluency correlated with the frontal lobe WMH index in AD, while drawing performance correlated with parietal and temporal lobe WMH indices in VaD.


CONCLUSIONS
A similar regional distribution of WMH between the three groups suggests a common (vascular) pathogenic factor leading to WMH in patients and controls. Our findings underscore the potential of regional WMH volumetry to determine correlations between subcortical pathology and cognitive impairment.
Gootjes
L
L
Alzheimer Memorial Center and Geriatric Psychiatry Branch, Dementia and Neuroimaging Section, Department of Psychiatry, Ludwig Maximilian University, Munich, Germany.
Teipel
S J
SJ
Zebuhr
Y
Y
Schwarz
R
R
Leinsinger
G
G
Scheltens
P
P
Möller
H-J
HJ
Hampel
H
H
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000473:pathology*; D001284:Atrophy; D001931:Brain Mapping; D015140:Dementia, Vascular / Q000473:pathology*; D005260:Female; D005625:Frontal Lobe / Q000473:pathology; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008609:Mental Status Schedule / Q000706:statistics & numerical data; D009413:Nerve Fibers, Myelinated / Q000473:pathology; D009426:Netherlands; D009778:Occipital Lobe / Q000473:pathology; D010296:Parietal Lobe / Q000473:pathology; D011594:Psychometrics; D012016:Reference Values