角膜激光共焦显微镜在糖尿病视网膜病变中的应用

目的　探讨角膜激光共焦显微镜在观察糖尿病视网膜病变（diabetic retinopathy，DR）患者角膜上皮下神经丛、角膜细胞密度及形态变化中的价值。方法　选取确诊的DR患者94例（114眼），其中非增生型糖尿病视网膜病变（non-proliferative diabetic retinopathy，NPDR）患者41例（52眼，NPDR组）、增生型糖尿病视网膜病变（proliferative diabetic retinopathy，PDR）患者53例（62眼，PDR组），收治时间2016年1月至2017年4月，同期糖尿病无眼底改变的患者40例（40眼）作为对照组，三组均采用角膜激光共焦显微镜进行检测，对比各组角膜上皮下神经丛、角膜细胞密度及形态的变化。结果　NPDR组和PDR组患者的角膜基底层、浅基质层、中基质层、深基质层的细胞密度均显著低于对照组（均为P<0.05）；PDR组患者的角膜基底层、浅基质层、中基质层、深基质层的细胞密度均显著低于NPDR组（均为P<0.05）；NPDR组和PDR组患者的角膜内皮细胞密度、六边形细胞比例、神经纤维密度、神经纤维长度均显著低于对照组（均为P<0.05），NPDR组和PDR组患者的内皮细胞变异率、神经分支密度均显著高于对照组（均为P<0.05）；PDR组患者的角膜内皮细胞密度、六边形细胞比例、神经纤维密度、神经纤维长度分别为（1962.0±117.3）个·mm^-2、46.1%±5.5%、（15.4±3.3）根·mm^-2、（6.2±2.7）mm·mm^-2，均显著低于NPDR组的（2381.4±144.0）个·mm^-2、58.2%±7.0%、（20.6±3.8）根·mm^-2、（8.6±2.4）mm·mm^-2（均为P<0.05），PDR组患者的内皮细胞变异率、神经分支密度均显著高于NPDR组（均为P<0.05）。结论　角膜激光共焦显微镜能有效观察DR患者角膜上皮下神经丛、角膜细胞密度及形态变化，为临床诊断、治疗提供指导。

Application of corneal laser confocal microscopy in diabetic retinopathy patients

Objective　To investigate the value of corneal laser confocal microscope in the diagnosis of corneal subepithelial plexus，corneal cell density and morphological changes of patients with diabetic retinopathy （DR）.Methods　Together 94 cases of confirmed DR （114 eyes），including 41 cases of non-proliferative diabetic retinopathy （NPDR group，52 eyes） and 53 cases of proliferative diabetic retinopathy （PDR group，62 eyes） were selected from January 2016 to April 2017，and meanwhile，40 diabetic patients （40 eyes） with no fundus abnormality were grouped as control group.Corneal laser confocal microscopy was used to compare the corneal subepithelial plexus，corneal cell density and morphological changes in the three groups.Results　The cell densities of the basal layer，the superficial stromal layer，the medium stromal layer and the deep stromal layer of the cornea in NPDR and PDR were significantly lower than those of the control group （all P<0.05），and the PDR group was significantly lower than the NPDR group （all P<0.05）.The corneal endothelial cell density，hexagonal cell ratio，nerve fiber density，and nerve fiber length in the NPDR and PDR group were significantly lower than those in the control group （all P<0.05）；and the variability of endothelial cell and nerve branch density in NPDR and PDR patients were significantly higher than those in the control group （all P<0.05）.The corneal endothelial cell density，hexagonal cell ratio，nerve fiber density，and nerve fiber length in the PDR group was （1962.0±117.3）·mm^-2，46.1%±5.5%，（15.4±3.3）·mm^-2，（6.2±2.7）mm·mm^-2，respectively，which were significantly lower than those in the NPDR group ［（2381.4±144.0）·mm^-2，58.2%±7.0%，（20.6±3.8）·mm^-2，（8.6±2.4）mm·mm^-2，respectively］（all P<0.05），but the variability of endothelial cell and nerve branch density in PDR group were significantly higher than those in the NPDR group （all P<0.05）.Conclusion　Corneal confocal microscopy can effectively observe the density and morphological changes in corneal subepithelial plexus and corneal cell in DR patients so as to provide guidance for clinical diagnosis and treatment.