Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
Transl Vis Sci Technol. 2020 Mar 9;9(4):5. doi: 10.1167/tvst.9.4.5. eCollection 2020 Mar.
To evaluate differences in parafoveal vascular density surrounding arterioles and venules in type 2 macular telangiectasia (MacTel).
Thirty-seven eyes (20 subjects) diagnosed with MacTel and 16 healthy eyes (10 subjects) were imaged with optical coherence tomography angiography between March 2016 and June 2019 in this single-center, observational, cross-sectional study. Arterioles and venules were manually identified, and perivascular density was generated using a custom MATLAB code. The primary outcome measure was the ratio of periarteriolar to perivenular vascular density (arteriovenous [A/V] capillary ratio) in the superficial and deep capillary plexuses across MacTel stages. The main secondary outcome measures were overall parafoveal vascular density (VD), periarteriolar VD, and perivenular VD.
In the superficial capillary plexus (SCP), the A/V capillary ratio was significantly higher in MacTel subjects than controls (0.914 vs. 0.892; = 0.0044). The greatest differences occurred between controls and nonproliferative MacTel subjects without optical coherence tomography evidence of disease ( = 0.0055). A/V capillary ratios progressed in a nonlinear fashion with MacTel severity, increasing from nonproliferative disease (0.912) to intraretinal proliferative disease (0.931), then decreasing in subretinal proliferative disease (0.905). Parafoveal VD in the SCP was lower in MacTel subjects than controls only in subretinal proliferative disease ( = 0.0130).
The A/V capillary ratio of the SCP is a quantifiable metric of vascular pathology in MacTel that occurs earlier than decline in parafoveal VD. Elevated A/V capillary ratios in MacTel are consistent with an early, disproportionately perivenular disruption in the SCP.
Findings inform MacTel pathogenesis through revealing early perivenular capillary loss and offer a new quantitative metric for earliest stage MacTel.
评估 2 型黄斑毛细血管扩张症（MacTel）周边动静脉血管密度的差异。
本单中心、观察性、横断面研究于 2016 年 3 月至 2019 年 6 月间对 37 只眼（20 名受试者）和 16 只健康眼（10 名受试者）进行光学相干断层扫描血管造影成像。手动识别动静脉，使用自定义 MATLAB 代码生成血管周围密度。主要观察指标是浅层毛细血管丛和深层毛细血管丛中动静脉（AV）毛细血管比在 MacTel 各期的变化。主要次要观察指标为整体旁中心区血管密度（VD）、动静脉周围 VD 和静脉周围 VD。
在浅层毛细血管丛（SCP）中，MacTel 受试者的 AV 毛细血管比值明显高于对照组（0.914 比 0.892；=0.0044）。在没有光学相干断层扫描疾病证据的非增生性 MacTel 受试者中，对照组和 MacTel 受试者之间的差异最大（=0.0055）。AV 毛细血管比值随 MacTel 严重程度呈非线性增加，从非增生性疾病（0.912）增加到视网膜内增生性疾病（0.931），然后在视网膜下增生性疾病中减少（0.905）。只有在视网膜下增生性疾病中，SCP 的 MacTel 受试者的旁中心区 VD 才低于对照组（=0.0130）。
SCP 的 AV 毛细血管比值是 MacTel 血管病变的一种可量化指标，其发生早于旁中心区 VD 下降。MacTel 中升高的 AV 毛细血管比值与 SCP 中早期、不成比例的静脉周围毛细血管破坏一致。
医学科学
