Singapore Eye Research Institute, Singapore National Eye Center, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Centre for Quantitative Medicine, Duke-National University of Singapore Graduate Medical School, Singapore.
Singapore Eye Research Institute, Singapore National Eye Center, Singapore; Centre for Quantitative Medicine, Duke-National University of Singapore Graduate Medical School, Singapore.
J Stroke Cerebrovasc Dis. 2014 Jan;23(1):43-50. doi: 10.1016/j.jstrokecerebrovasdis.2012.09.002. Epub 2012 Oct 23.
Fractal analysis is a method used to quantify the geometric branching complexity and density of retinal vessels. This study examined the relationship of retinal vascular fractal dimension and other retinal vascular parameters with cognitive dysfunction in an older Asian population. Subjects aged 60 years and older from the Singapore Malay Eye Study were selected for analysis. Retinal vascular fractal dimension (Df) and other quantitative retinal vascular parameters (branching angle, tortuosity, and caliber) were measured based on a standardized grading protocol from photographs of the retinal fundus using a computer-assisted program. Qualitative retinal signs were also assessed from photographs. Cognitive dysfunction was defined as a locally validated Abbreviated Mental Test (AMT) score ≤6/10 in participants with 0-6 years of formal education and an AMT score ≤8/10 in those with more than 6 years of formal education. Cognitive dysfunction was identified in 262 of the 1202 participants (21.8%). Decreased retinal vascular Df was significantly associated with lower AMT score (P = .019). In multivariate logistic regression analysis, participants with lower retinal vascular Df values were more likely to have cognitive dysfunction (odds ratio, 1.71; 95% confidence interval, 1.03-2.82, comparing the lowest and highest Df quintiles). In subgroup analysis stratified for cardiovascular risk factors, this association was present in participants with hypertension and current smokers. Other retinal vascular signs were not associated with cognitive dysfunction. Decreased retinal vascular Df is associated with cognitive dysfunction in older persons. Rarefaction of the retinal vasculature may reflect similar changes in the cerebral microvasculature that may contribute to cognitive deterioration.
分形分析是一种用于量化视网膜血管几何分支复杂性和密度的方法。本研究旨在探讨老年亚洲人群中视网膜血管分形维数与其他视网膜血管参数与认知功能障碍的关系。本研究从新加坡马来人眼部研究中选择了年龄在 60 岁及以上的受试者进行分析。基于眼底照相的标准化分级方案，使用计算机辅助程序测量视网膜血管分形维数（Df）和其他定量视网膜血管参数（分支角、扭曲度和口径）。还从眼底照相评估定性视网膜病变。认知功能障碍定义为在受教育年限为 0-6 年的参与者中，局部验证的简易精神状态检查（AMT）评分≤6/10，而在受教育年限超过 6 年的参与者中，AMT 评分≤8/10。在 1202 名参与者中，有 262 名（21.8%）存在认知功能障碍。视网膜血管 Df 降低与 AMT 评分较低显著相关（P =.019）。在多变量逻辑回归分析中，视网膜血管 Df 值较低的参与者发生认知功能障碍的可能性更大（比值比，1.71；95%置信区间，1.03-2.82，比较最低和最高 Df 五分位数）。在按心血管危险因素分层的亚组分析中，这种相关性存在于高血压和当前吸烟者中。其他视网膜血管病变与认知功能障碍无关。视网膜血管 Df 的降低与老年人的认知功能障碍有关。视网膜血管稀疏可能反映了大脑微血管的类似变化，这可能导致认知能力下降。
