[Peripapillary and macular vessel density in eyes with different phases of thyroid-associated ophthalmopathy].

Objective: To analyze the characteristics of vessel density in the optic disc and macular area of patients with different phases of thyroid-associated ophthalmopathy (TAO) and their correlation with visual function. Methods: This case-control study was conducted at the Department of Ophthalmology of Peking Union Medical College Hospital between June 2019 and September 2019. TAO patients and healthy volunteers were included in the study. Patients with a clinical activity score greater than or equal to 3 points were categorized as active TAO. Dysthyroid optic neuropathy (DON) patients with a course less than 6 months were categorized as acute phase of DON, and those more than 6 months were in the chronic group. Healthy volunteers were in the control group. Each group included 12 subjects, with right eyes for analysis. There were 6 males and 6 females in each group. All participants underwent comprehensive ophthalmic examination including best corrected visual acuity and visual field examination for the mean defect (MD). Best corrected visual acuity was subsequently converted to logarithm of minimum angle of resolution (logMAR). Optical coherence tomography was used to measure the thickness of the retinal nerve fiber layer (RNFL) and retinal ganglion cell complex (GCC). Optical coherence tomography angiography was used to the peripapillary and macular vessel density. The differences in the vessel densities in the optic disc and macular area between groups and their correlation with different factors were analyzed. Analysis of variance, non-parametric Mann-Whitney U test and Spearman coefficient were conducted for statistical analysis. Results: There was no significant difference in age among the four groups (P>0.05). The logMAR of the acute DON group was 0.1 (0.0, 0.2), worse than the control group, which was 0.0 (0.0, 0.0) (U=114.000, P<0.05). The overall vessel densities of the optic disc in acute DON and chronic DON were significantly lower than the control group (54.70%±2.31% and 54.31%±3.65% vs. 57.54%±2.17%; t=3.104, 2.636; both P<0.05). The overall superficial vessel densities of the macular area in active TAO, acute DON and chronic DON were significantly lower than the control group (46.07%±3.06% and 42.26%±5.05% and 45.63%±3.87% vs. 49.34%±3.08%), and the differences were statistically significant (t=2.614, 4.147, 2.603; all P<0.05). There was no statistically significant difference in the size of the foveal avascular zone or the density of deep blood vessels in the macular area among the four groups (all P>0.05). In the active TAO period, there was no correlation between the MD value, RNFL thickness, GCC thickness and the vessel densities of the optic disc and macular area (all P>0.05). The vascular density of the whole layer of the optic disc in acute DON was negatively correlated with the MD value (r=-0.591, P<0.05) and positively correlated with the RNFL thickness and GCC thickness (r=0.595, 0.693; both P<0.05). In chronic DON, the overall capillary density of the optic disc was negatively correlated with the MD value (r=-0.673, P<0.05); the superficial overall blood vessel density of the macular area was positively correlated with the thickness of RNFL and GCC (r=0.732, 0.712;both P<0.01). Conclusions: In active TAO, only the blood supply to the superficial layer of the macular area is decreased. In the acute and chronic phases of DON, the blood supply to the superficial layer of the macular area and the optic disc is both reduced; the smaller the blood vessel density, the more severe the visual field defect, and the thinner the RNFL and GCC. (Chin J Ophthalmol, 2020, 56:824-831).目的： 分析不同病程甲状腺相关眼病（TAO）视盘及黄斑区血管密度特征及其与视功能的相关性。 方法： 病例对照研究。纳入2019年6至9月就诊于北京协和医院眼科的36例TAO患者及同期年龄匹配的健康志愿者12名。其中TAO临床活动性评分≥3分的12例患者为TAO活动期组，患有甲状腺相关眼病视神经病变（DON）且病程≤6个月的12例患者为DON急性期组，患有DON且病程>6个月的12例患者为DON慢性期组，健康志愿者为对照组，研究均取右眼数据进行分析。每组男性、女性均为6人。所有受试者行最佳矫正视力及视野检查，最佳矫正视力转换为最小分辨角对数视力进行分析；采用相干光层析成像术测量视网膜神经纤维层（RNFL）、视网膜神经节细胞复合体（GCC）厚度；采用相干光层析血管成像术测量视盘及黄斑区血管密度。分析各组间视盘及黄斑区血管密度的差异及其与不同因素的相关性。统计学方法主要采用方差分析、Mann-Whitney U检验及Spearman相关分析。 结果： 4个组受检者年龄差异无统计意义（P>0.05）。DON急性期组最佳矫正视力为0.1（0.0，0.2），较对照组0.0（0.0，0.0）差，差异有统计学意义（U=114.000，P<0.05）。DON急性期组及DON慢性期组整体视盘全层血管密度（54.70%±2.31%、54.31%±3.65%）均低于对照组（57.54%±2.17%），差异有统计学意义（t=3.104，2.636；均P<0.05）。TAO活动期组、DON急性期组和DON慢性期组黄斑区整体浅层血管密度（46.07%±3.06%、42.26%±5.05%、45.63%±3.87%）均低于对照组（49.34%±3.08%），差异有统计学意义（t=2.614，4.147，2.603；均P<0.05）。4个组间黄斑中心凹无血管区面积及黄斑区深层血管密度差异均无统计学意义（均P>0.05）。TAO活动期组视盘及黄斑区血管密度与视野平均缺损值、RNFL及GCC厚度均无相关性（均P>0.05）。DON急性期组整体视盘全层血管密度与视野平均缺损值呈负相关（r=-0.591，P<0.05），与RNFL、GCC厚度呈正相关（r=0.595，0.693；均P<0.05）；DON慢性期组整体视盘毛细血管密度与视野平均缺损值呈负相关（r=-0.673，P<0.05），黄斑区整体浅层血管密度与RNFL、GCC厚度呈正相关（r=0.732，0.712；均P<0.01）。 结论： TAO活动期仅黄斑区浅层血液供应减少。DON急、慢性期黄斑区浅层和视盘的血液供应均减少，且血管密度越小，RNFL及GCC厚度越薄，视野缺损越严重。（中华眼科杂志，2020，56：824-831）.