目的：应用活体共聚焦显微镜（in vivo confocal microscopy，IVCM）观察视网膜激光光凝术对角膜上皮下神经的影响。方法：收集行视网膜激光光凝术的患者 36 例 46 眼，分为糖尿病性视网膜病变（diabetic retinopathy，DR）组（14 例 22 眼）与非DR组（22 例 24 眼），在治疗前及治疗后 1 周、1 个月应用IVCM采集两组角膜基底层下神经纤维图像，使用Image J和Neuron J软件计算其长度及密度。结果：DR组术前角膜神经纤维主干密度（corneal nerve fiber density，CNFD）、角膜神经纤维分支密度（corneal nerve branch density，CNBD）和角膜神经纤维长度（corneal nerve fiber length，CNFL）均低于非DR组，角膜神经弯曲度（corneal nerve fiber tortuosity，CNFT）高于非DR组。两组间角膜神经总分支节点密度（corneal total branch node，CTBN）无显著差异。DR组光凝术后CNFD，CNFL测量值持续降低，术前、术后 1 周、术后 1 个月 3 个观察时段两两之间的差异有统计学意义；光凝术后 1 个月CNFT与术前的差异有统计学意义。非DR组光凝术后CNFD，CNFL持续降低，术前、术后 1 周、术后1个月3个观察时段两两之间的差异有统计学意义；CNBD持续升高，术后 1 周、术后 1 个月测量值与术前的差异有统计学意义；CNFT持续升高，术后 1 周、术后 1 个月测量值与术前的差异均有统计学意义。结论：IVCM结合附属软件可量化评估角膜上皮下神经，糖尿病状态和视网膜激光光凝均可对角膜上皮下神经造成损伤。

Objective: To evaluate the effect of retinal photocoagulation on corneal sub-basal nerve using in vivo confocal microscopy （IVCM）. Methods: In this study, 46 eyes of 36 cases were enrolled. All patients were divided intotwo groups, 22 eyes in the diabetic retinopathy （DR） group and 24 eyes in the non-diabetic retinopathy （NDR） group. IVCM images were obtained to observe sub-basal nerve plexus before retinal photocoagulation and 1 week, 1 mouth after the treatment. Image J and Neuron J software were used for analysis. Results: In the DR group, before retinal photocoagulation, the corneal nerve fiber density （CNFD）, corneal nerve branch density （CNBD） and corneal nerve fiber length （CNFL） were lower than those in the NDR group while the corneal nerve fiber tortuosity （CNFT） was higher than that in the NDR group. There were no significant differences in corneal total branch node （CTBN） between two groups. The CNFD, CNFL were decreased constantly in the DR group. No statistical significance was observed in either CNBD or CTBN at any time point. After the treatment, the CNFT was enhanced; however, significant differences were noted between 1 week and 1 month. In the NDR group, CNFD, CNFL were declined continually to 1 month, whereas CNBD was increased. CTBN was slightly elevated at each time point without statistical significance. After treatment, CNFT was significantly increased, whereas no statistical significance was observed between 1 week and 1 month. Conclusion: IVCM combined with assistant software could be used to quantify corneal sub-basal nerve fiber. Retinal photocoagulation as well as diabetes mellitus can injure corneal sub-basal nerve fiber.

目的：观察健康中老年人群中心凹视觉敏感度阈值(foveal threshold，FT)及光相干断层扫描血管成像(optical coherence tomography angiography，OCTA)的双眼对称性。方法：横断面观察性研究。纳入33例66眼，测量并比较眼灌注压(ocular perfusion pressure，OPP)，FT，黄斑区3 mm × 3 mm范围内中心凹无血管区面积(non-flow area，NFA)，浅层视网膜血管密度(superior vessel density，SVD)和深层视网膜血管密度(deep vessel density，DVD)的双眼对称性；分析各指标双眼差值、均值及其比值与年龄、性别的相关性。结果：配对样本t检验结果显示除FT(t=?2.118，P=0.042)外，左右眼OPP，NFA，SVD和DVD差异均无统计学意义(P>0.05)；Pearson相关性分析和同类相关系数(intra-class correlation coefficient，ICC)检验结果显示5项指标左右眼测量值相关强度由强到弱为OPP>FT>NFA>DVD>SVD；Bland-Altman分析结果提示5项指标双眼间一致性良好。5项指标的双眼对称性不随性别、年龄改变。结论：健康中老年人群FT、黄斑区NFA，SVD及DVD的测量值具有双眼对称性。

Objective: To observe the interocular symmetry of foveal threshold (FT) and optical coherence tomography angiography (OCTA) parameters in healthy middle-aged and elderly subjects. Methods: Cross-sectional observational study. Sixty-six eyes from thirty-three subjects were enrolled to compare binocular ocular perfusion pressure (OPP), FT, non-flow area (NFA), superior vessel density (SVD) and deep vessel density (DVD) in a 3 mm × 3 mm OCTA scan of macula. The interocular symmetry of all the parameters was analyzed; the correlations of the differences (△), mean value (m) and the ratio of all the parameters with age and gender were analyzed. Results: There was no significant interocular difference revealed by paired-samples t-tests in all the parameters (P>0.05) except FT (t=?2.118, P=0.042), while the rank of Pearson’s correlation index and intraclass correlation coefffcient (ICC) from strong to weak was OPP > FT > NFA > DVD > SVD. The interocular symmetry of all the parameters was proved to be good with Bland-Altman plots, and it changed little with the variations of age and gender. Conclusion: Interocular symmetries of FT and OCTA parameters are observed in healthy middle-aged and elderly subjects.