Poor performance in Clock-Drawing Test associated with visual memory deficit and reduced bilateral hippocampal and left temporoparietal regional blood flows in Alzheimer's disease patients.
OBJECTIVE
To investigate the associations of Clock-Drawing Test (CDT) score with neuropsychological test scores and regional cerebral blood flow.


METHODS
Twenty-five patients (normal aging, n = 2; mild cognitive impairment, n = 7; Alzheimer's disease [AD], n = 16) participated in this study. Their average age was 74.8 years.


RESULTS
CDT score correlated well with the neuropsychological test scores of Mini-Mental State Examination, Clinical Dementia Rating, immediate visual memory, delayed visual memory, and IQ evaluated by Koh's block design. CDT score also had a statistically significant correlation with the regional blood flow in the left hippocampal region as evaluated on 3-D stereotaxic region-of-interest template analysisapplied to single-photon emission computed tomography images. Using a cut-off point of 8/9 in the CDT, the high-CDT group had significantly higher delayed visual memory and IQ scores than the low-CDT group. Moreover, the high-CDT group had significantly higher regional blood flows in the left parietal, left angular and bilateral hippocampal regions than the low-CDT group.


CONCLUSIONS
CDT score correlates well with regional cerebral blood flow that is decreased in the early stage of AD.
Takahashi
Megumi
M
Department of Psychiatry, Kitasato University School of Medicine, Sagamihara, Japan. megumita@kitasato-u.ac.jp
Sato
Aiko
A
Nakajima
Keisuke
K
Inoue
Aya
A
Oishi
Satoru
S
Ishii
Takayoshi
T
Miyaoka
Hitoshi
H
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000523:psychology; D003337:Corpus Callosum / Q000098:blood supply / Q000000981:diagnostic imaging; D004292:Dominance, Cerebral / Q000502:physiology*; D005260:Female; D006624:Hippocampus / Q000098:blood supply* / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D011939:Mental Recall / Q000502:physiology*; D009483:Neuropsychological Tests / Q000706:statistics & numerical data*; D010296:Parietal Lobe / Q000098:blood supply* / Q000000981:diagnostic imaging; D010364:Pattern Recognition, Visual / Q000502:physiology*; D011594:Psychometrics; D011597:Psychomotor Performance / Q000502:physiology*; D012016:Reference Values; D012039:Regional Blood Flow / Q000502:physiology; D013702:Temporal Lobe / Q000098:blood supply* / Q000000981:diagnostic imaging; D015899:Tomography, Emission-Computed, Single-Photon