Department of Vitreoretinal Diseases, Medical Research Foundation, Sankara Nethralaya, Visakhapatnam, India.
RS Mehta Jain Department of Biochemistry, Vision Research Foundation, Visakhapatnam, India.
Indian J Ophthalmol. 2020 Mar;68(3):484-489. doi: 10.4103/ijo.IJO_783_19.
To evaluate the differences in vascular indices in different scan sizes of optical coherence tomography angiography (OCTA) images in normal persons versus persons with diabetic retinopathy.
OCTA scans of diabetic patients and age-matched controls were performed by a single operator. Automated quantification of vascular indices of the superficial plexus was analyzed in two angiocubes of 3 × 3 mm and 6 × 6 mm, respectively. The agreement was analyzed with the intraclass correlation coefficient (ICC) and Bland-Altman plots.
Forty-eight eyes with DR, 36 eyes with no diabetic retinopathy (No DR), and 26 eyes of age-matched normals were scanned. The foveal avascular zone (FAZ) area and perimeter were highly reliable and interchangeable in both angiocubes of the healthy eyes (ICC 0.94, 0.75), No DR (ICC 0.92, 0.85), and DR eyes (ICC 0.97, 0.89). The vessel density (VD) and perfusion density (PD) showed excellent agreement in normal (ICC 0.89, 0.80) and No DR eyes (ICC 0.92, 0.81). But, only fair ICC was observed in DR eyes (0.56, 0.42).
The FAZ area and perimeter showed excellent reproducibility. The macular perfusion parameters are not interchangeable despite automated estimation. The variability is more with changes in the vascular network like DR. This variability should be considered while comparing different scans.
评估正常人及糖尿病视网膜病变患者的光学相干断层扫描血管造影（OCTA）图像不同扫描大小的血管指数的差异。
由一名操作者对糖尿病患者和年龄匹配的对照组进行 OCTA 扫描。分别对 3×3mm 和 6×6mm 的两个血管立方体进行自动量化分析浅层丛的血管指数。采用组内相关系数（ICC）和 Bland-Altman 图进行一致性分析。
共扫描了 48 只 DR 眼、36 只无糖尿病视网膜病变（No DR）眼和 26 只年龄匹配的正常眼。健康眼（ICC 0.94，0.75）、No DR 眼（ICC 0.92，0.85）和 DR 眼（ICC 0.97，0.89）的黄斑中心凹无血管区（FAZ）面积和周长高度可靠且可互换。正常眼（ICC 0.89，0.80）和 No DR 眼（ICC 0.92，0.81）的血管密度（VD）和灌注密度（PD）具有极好的一致性。但在 DR 眼中，仅观察到适度的 ICC（0.56，0.42）。
FAZ 面积和周长具有极好的可重复性。尽管进行了自动评估，但黄斑灌注参数不可互换。像 DR 这样的血管网络变化会导致更大的变异性。在比较不同扫描时，应该考虑到这种可变性。
