Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.
Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.
Ophthalmol Retina. 2023 Dec;7(12):1042-1050. doi: 10.1016/j.oret.2023.07.020. Epub 2023 Jul 28.
To evaluate the association of microvascular lesions on ultrawidefield (UWF) color fundus (CF) images with retinal nonperfusion (RNP) up to the midperiphery on single-capture widefield (WF) OCT angiography (OCTA) in patients with diabetic retinopathy (DR).
Cross-sectional study.
Seventy-five eyes of 50 patients with mild to severe nonproliferative DR (NPDR) and proliferative DR (PDR) were included in this analysis.
ETDRS level and presence of predominantly peripheral lesions (PPLs) were assessed on UWF-CF images acquired with a Zeiss Clarus 700. Single-capture 65°-WF-OCTA was performed using a PlexElite prototype (Carl Zeiss Meditec, Inc.). A custom grid consisting of a central ETDRS grid extended by 2 rings reaching up to the midperiphery was overlaid to subdivide retinal areas visible on WF-OCTA en face images. Retinal nonperfusion was measured in each area and in total. Nonperfusion index (NPI) was calculated from total RNP. On UWF-CF images, the number of microaneurysms, hemorrhages, neovascularizations, and areas with intraretinal microvascular abnormalities (IRMAs) were evaluated using the same grid.
Association of diabetic lesions with RNP was calculated using Spearman correlations (r).
Median RNP on WF-OCTA was 0 mm (0-0.9), 4.9 mm (1.9-5.4), 23.4 mm (17.8-37), and 68.4 mm (40.8-91.7) in mild, moderate, and severe NPDR and PDR, respectively. We found a statistically significant correlation (P < 0.01) of overall RNP (r = 0.96,) and NPI (r = 0.97) on WF-OCTA with ETDRS level. Number of grid-fields affected by IRMAs on CF images was highly associated with NPI (r = 0.86, P < 0.01). Intraretinal microvascular abnormalities and RNPs had similar topographic distributions with high correlations in affected areas. Eyes with PPLs (n = 43 eyes, 57%) on CF images had a significantly higher NPI (P = 0.014) than eyes without PPLs.
The combination of UWF-CF imaging and single-capture WF-OCTA allows precise and noninvasive analysis of the retinal vasculature up to the midperiphery in patients with DR. The presence and extent of IRMAs on CF images may serve as an indicator for underlying RNP, which is more pronounced in eyes with PPLs.
FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
评估超广角（UWF）眼底彩色图像上的微血管病变与单张宽视野（WF）OCTA 视网膜无灌注（RNP）之间的关系，直至糖尿病视网膜病变（DR）患者的周边中部。
横断面研究。
本分析纳入了 50 名患有轻度至重度非增生性 DR（NPDR）和增生性 DR（PDR）的患者的 75 只眼。
使用 Zeiss Clarus 700 获得 ETDRS 分级和主要周边病变（PPLs）的存在情况。使用 PlexElite 原型（卡尔蔡司 Meditec，Inc.）进行单次拍摄 65°-WF-OCTA。使用包含中央 ETDRS 网格扩展的两个环的自定义网格，直至周边中部，覆盖 WF-OCTA 正面图像上可见的视网膜区域。在每个区域和总区域测量视网膜无灌注。从总 RNP 计算无灌注指数（NPI）。在 UWF-CF 图像上，使用相同的网格评估微动脉瘤、出血、新生血管和视网膜内微血管异常（IRMAs）的数量。
使用 Spearman 相关系数（r）计算糖尿病病变与 RNP 的相关性。
WF-OCTA 上的中位数 RNP 分别为 0 毫米（0-0.9）、4.9 毫米（1.9-5.4）、23.4 毫米（17.8-37）和 68.4 毫米（40.8-91.7）在轻度、中度和重度 NPDR 和 PDR 中。我们发现总体 RNP（r=0.96，P<0.01）和 NPI（r=0.97）与 WF-OCTA 上的 ETDRS 分级之间存在统计学显著相关性。CF 图像上受 IRMAs 影响的网格区域数量与 NPI 高度相关（r=0.86，P<0.01）。视网膜内微血管异常和 RNP 具有相似的拓扑分布，在受影响区域具有高度相关性。CF 图像上有 PPLs（n=43 只眼，57%）的眼的 NPI 明显更高（P=0.014）。
UWF-CF 成像与单次拍摄 WF-OCTA 的结合可在 DR 患者中精确、无创地分析直至周边中部的视网膜血管。CF 图像上 IRMAs 的存在和程度可能是潜在 RNP 的指标，在有 PPLs 的眼中更为明显。
本文末尾的脚注和披露中可能包含专有或商业披露。
