Objectives: Retinal vein occlusion (RVO) is the second most common retinal vascular disease worldwide, and the retinal perfusion status is closely related to the prognosis of the disease. Macular perfusion status is particularly correlated with visual acuity. This study aims to investigate the changes in macular perfusion indicators in RVO using optical coherence tomography angiography (OCTA) and analyze the correlation between macular perfusion status and visual acuity.
Methods: This cross-sectional study included 41 RVO patients, who were divided into 2 groups based on the occlusion site: 18 cases in the central retinal vein occlusion (CRVO) group and 23 cases in the branch retinal vein occlusion (BRVO) group. Additionally, they were categorized into ischemic RVO (23 cases) and non-ischemic RVO (16 cases) groups based on the presence of ischemia (2 eyes were excluded due to hemorrhage obscuring the peripheral retina, making it impossible to confirm the area of non-perfusion). A control group of 29 healthy individuals matched by sex and age was also recruited. Macular perfusion indicators were measured using OCTA, and the correlation between macular perfusion status and visual acuity was analyzed.
Results: Compared with healthy eyes, RVO eyes showed an increased foveal avascular zone (FAZ) area and significantly reduced superficial and deep vessel density (P<0.001). However, there were no significant differences in central foveal thickness (CFT) or macular perfusion indicators between the CRVO and BRVO groups (P>0.05). The best corrected visual acuity (BCVA) at the logarithm of the minimum angle of resolution (logMAR BCVA) was significantly negatively correlated with both superficial and deep retinal vessel density in RVO eyes (unstandardized coefficient B=-0.039, B=-0.042; P=0.017, P=0.040). The average BCVA in the ischemic RVO group was significantly worse than that in the non-ischemic RVO group (0.82±0.44 vs 0.45±0.29, P=0.007). The ischemic RVO group also had a larger FAZ area (P=0.003) and lower superficial and deep retinal vessel density (P<0.001, P=0.008, respectively) compared with the non-ischemic RVO group. The severity of macular ischemia did not correspond directly with the peripheral ischemia severity in RVO.
Conclusions: Macular perfusion status is significantly reduced in RVO eyes compared to healthy eyes, which negatively impacts and limits visual acuity in RVO patients. Eyes with ischemic RVO have poorer visual acuity and macular perfusion status than those with non-ischemic RVO. OCTA is advantageous for observing vascular morphology and quantifying macular perfusion status, making it an effective tool for assessing disease progression.
目的: 视网膜静脉阻塞(retinal vein occlusion，RVO)是全球第二常见的视网膜血管疾病，视网膜的灌注状态与疾病预后相关，黄斑区视网膜灌注状态与视力密切相关。本研究旨在应用光学相干断层扫描血管造影(optical coherence tomography angiography，OCTA)测量RVO黄斑灌注指标的变化以及黄斑灌注状态与视力的相关性。方法: 采用横断面研究设计，根据阻塞部位将41例RVO患者分为视网膜中央静脉阻塞(central retinal vein occlusion，CRVO)组18例和视网膜分支静脉阻塞(branch retinal vein occlusion，BRVO)组23例，根据是否存在缺血分为缺血型RVO组23例和非缺血型RVO组16例(2例患眼周边视网膜被出血遮蔽，无法确认无灌注区面积而被排除)。同时，招募性别和年龄匹配的29名健康人作为对照组。应用OCTA测量并比较黄斑灌注指标，分析黄斑灌注状态与视力的相关性。结果: 与健康眼相比，RVO眼的中央凹无血管区(foveal avascular zone，FAZ)面积增大，浅层和深层血流密度明显降低(P<0.001)，但CRVO组与BRVO组中央凹厚度(central fovea thickness，CFT)和黄斑灌注指标比较差异无统计学意义(P>0.05)。最小分辨角对数最佳矫正视力(best corrected visual acuity at logarithmoftheminimumangleofresolution，logMAR BCVA)与RVO浅层和深层血流密度呈显著负相关性(非标准化系数B=-0.039、B=-0.042，P=0.017、P=0.040)。缺血型RVO组平均最佳矫正视力为0.82±0.44，高于非缺血型RVO组的0.45±0.29，差异有统计学意义(P=0.007)；缺血型RVO组较非缺血型RVO组伴有较大的FAZ面积(P=0.003)、较低的浅层和深层血管密度(P<0.001、P=0.008)，黄斑缺血的严重程度与RVO周边缺血程度并不一致。结论: 与健康眼相比，RVO眼的黄斑灌注状态明显下降，影响并限制了RVO患者的视力。缺血型RVO患眼视力和黄斑灌注状态较非缺血型RVO患眼更差。OCTA在观察血管形态和量化黄斑灌注状态方面具有优势，可作为评估疾病进展的有效检查手段。.
Keywords: best corrected visual acuity; macular perfusion status; optical coherence tomography angiography; retinal ischemia; retinal vein occlusion.