Ophthalmic Surg Lasers Imaging Retina. 2021 Mar;52(3):116-122. doi: 10.3928/23258160-20210302-01. Epub 2021 Mar 1.
To quantify fractal dimension (FD) by mass-radius method in optical coherence tomography angiography (OCTA) images and characterize microvascular differences in eyes with and without diabetic retinopathy (DR).
A retrospective study was conducted using OCTA images of 3 mm × 3 mm and 6 mm × 6 mm scans for superficial and deep capillary plexuses from 49 control eyes and 58 eyes with DR.
Analysis of variance showed a significant difference between the FD of control and diabetic eyes in deep plexus scans, and the 3 mm × 3 mm superficial plexus scan ( < .05). In the 3 mm × 3 mm superficial plexus, the FD of severe nonproliferative DR (NPDR) and proliferative DR (PDR) were significantly lower compared to control. The scans of the deep plexus showed only severe NPDR was significantly reduced in the 6 mm × 6 mm scan, whereas moderate NPDR, severe NPDR, and PDR were significantly lower in the 3 mm × 3 mm scan.
The study suggests the use of FD as a measure of microvascular dropout in DR. .
利用体质量-半径法对光相干断层扫描血管造影（OCTA）图像中的分形维数（FD）进行量化，并对无糖尿病视网膜病变（DR）和有 DR 的眼的微血管差异进行特征描述。
本回顾性研究使用 OCTA 对 49 只对照眼和 58 只 DR 眼的浅层和深层毛细血管丛的 3 mm×3 mm 和 6 mm×6 mm 扫描进行了分析。
方差分析显示，深层丛扫描中对照组和糖尿病组的 FD 存在显著差异，3 mm×3 mm 浅层丛扫描也存在显著差异（<0.05）。在 3 mm×3 mm 的浅层丛中，严重非增殖性 DR（NPDR）和增殖性 DR（PDR）的 FD 明显低于对照组。深层丛扫描仅显示严重 NPDR 在 6 mm×6 mm 扫描中显著降低，而中度 NPDR、严重 NPDR 和 PDR 在 3 mm×3 mm 扫描中显著降低。
研究表明，FD 可作为评估 DR 中微血管丢失的一种测量方法。
