Faculty of Medicine, University of Coimbra.
Department of Psychology and Communication, University Institute of Maia.
Neuropsychology. 2019 Jul;33(5):617-632. doi: 10.1037/neu0000549. Epub 2019 Apr 15.
This study aimed to understand the relationship between the Clock Drawing Test (CDT) and decreased blood flow in mild cognitive impairment (MCI) patients, using single-photon emission computed tomography.
We characterized regional cerebral blood flow (rCBF) and the correlation with clinical variables and future conversion to dementia in 94 amnestic MCI patients. Blood perfusion data was correlated with the CDT (quantitative and qualitative scores) in order to evaluate their relationship and usefulness in predicting conversion to dementia.
MCI patients displayed reduced rCBF in brain areas including the caudate nucleus; the frontal, parietal, and temporal lobes; as well as the cerebral cortex and cerebellum. The decrease in rCBF was higher for patients who later developed dementia. At baseline, CDT scores of these patients correlated with hypoperfusion in cortical and subcortical areas typically affected in Alzheimer's disease (AD) median 3 years before developing dementia. CDT total score was significantly correlated with rCBF in the left temporal lobe and the putamen; the analysis of rCBF in Brodmann areas showed significant correlations between the several clock elements (face, numbers, and hands), underlying qualitative errors (stimulus-bound response and conceptual deficit), and rCBF, most significantly in the left inferior temporal gyrus, posterior entorhinal cortex, posterior cingulate cortex, left parahippocampal cortex, and left inferior prefrontal gyrus.
This study showed that a quantitative score and a qualitative assessment of clock drawing (error analysis) corresponded to dysfunction in AD key areas at an early stage, supporting the CDT utility in the detection of prodromal AD. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
本研究旨在使用单光子发射计算机断层扫描（SPECT）了解简易智力状态检查（CDT）与轻度认知障碍（MCI）患者脑血流量下降之间的关系。
我们对 94 例遗忘型 MCI 患者的局部脑血流（rCBF）特征以及与临床变量的相关性和未来向痴呆的转化进行了描述。为了评估它们与痴呆转化的相关性和预测价值，将血流灌注数据与 CDT（定量和定性评分）相关联。
MCI 患者的大脑区域包括尾状核、额叶、顶叶和颞叶以及大脑皮层和小脑的 rCBF 降低。以后发展为痴呆的患者 rCBF 下降更为明显。在基线时，这些患者的 CDT 评分与皮质和皮质下区域的灌注减少相关，这些区域通常是阿尔茨海默病（AD）的典型病变部位，中位数为 3 年前出现痴呆。CDT 总分与左侧颞叶和壳核的 rCBF 显著相关；Brodmann 区 rCBF 分析显示，几个时钟元素（面部、数字和手）、潜在的定性错误（刺激绑定反应和概念缺陷）与 rCBF 之间存在显著相关性，在左侧下颞叶、后内嗅皮质、后扣带回皮质、左侧海马旁回和左侧下额前回更为显著。
本研究表明，CDT 的定量评分和定性评估（错误分析）与 AD 关键区域的早期功能障碍相对应，支持 CDT 在检测前驱 AD 中的作用。（PsycINFO 数据库记录（c）2019 APA，保留所有权利）。
