KHẢO SÁT MỐI TƯƠNG QUAN GIỮA BIẾN ĐỔI HỆ VI MẠCH VÕNG MẠC TẠI HOÀNG ĐIỂM BẰNG MÁY OCT-A VÀ THỊ LỰC TRÊN BỆNH NHÂN TẮC NHÁNH TĨNH MẠCH VÕNG MẠC

Abstract

Objectives: To describe the qualitative changes, identify the quantitative changes of the retinal microvasculature at the macula using OCT-A and investigate the correlation between these changes and visual acuity in eyes with resolved macular edema following BRVO. Materials and method: This is a cross-sectional observational study assessing 66 eyes of 33 patients with resolved macular edema following BRVO who came to the specialist clinic of the Vitreo-Retinopathy department in Ho Chi Minh City Eye Hospital from 6/2022 to 10/2022. Results: At the SCP level: the most common lesion was tortuous dilated capillaries, followed by disruption of FAZ, the least common was the presence of P–NPA areas. At the DCP level: the enlargement of nonperfusion areas was common. The mean FAZ area in BRVO eyes and healthy eyes were 0.38 ± 0.14 mm² and 0.27 ± 0.1 mm², respectively. The difference in the mean FAZ area between BRVO eyes with resolved macular edema and healthy eyes was statistically significant (p < 0.001). The mean macula perfusion density in BRVO eyes and healthy eyes were 30.66 ± 4.32% and 33.9 ± 2.84%, respectively. The difference in the mean macular perfusion density between BRVO eyes with resolved macular edema and healthy eyes was statistically significant (p < 0.001). Only FAZ area was positively correlated with BCVA logMAR in BRVO eyes. There was no correlation between macular perfusion density and visual acuity outcome. Conclusion: There were significant ischemic changes in the retinal microvasculature at the macula in BRVO eyes compared to healthy eyes at the time when macular edema had completely resolved. There was a positive correlation between the FAZ area identified by OCT-A and BCVA logMAR in BRVO patients with resolved macular edema.