Ⅱ型糖尿病患者角膜细胞形态学特征的共焦显微镜观察

Morphologic characteristics of cornea in type 2 diabetcs observed with confocal microscopy

目的探讨II型糖尿病患者的角膜在共焦显微镜下各层细胞形态学特征。方法应用Confoscan3.0共焦显微镜对120例(146只眼)II型糖尿病患者和36例(36只眼)同年龄对照组的中央角膜进行检查,依据双目间接眼底镜和眼底荧光血管造影检查的结果,将糖尿病患者分为三组:糖尿病无眼底改变(NDRP)组、非增生性糖尿病视网膜病变(NPDR)组、增生性糖尿病视网膜病变(PDR)组,记录角膜各层细胞的图像,并对其进行分析。结果共焦显微镜下可以观察到糖尿病引起的角膜神经营养性上皮病变;和对照组比较,2型糖尿病患者角膜上皮下神经丛神经分支密度减少,神经纤维的密度在PDR组明显减少,NPDR组、NDRP组的减少不明显。角膜基质中形态异常的神经纤维在糖尿病组中出现的机率也明显高于对照组;角膜前基质细胞密度在PDR组有明显减少,后基质细胞在NPDR组和PDR组均明显降低,NDRP组减少不明显;糖尿病组的后弹力膜层病变表现为特征性的皱折形成;糖尿病各组角膜内皮细胞密度较对照组无显著性差异,但糖尿病各组的细胞面积变异系数高于对照组,六角形细胞所占的百分比在糖尿病各组均较对照组减少,且随着糖尿病视网膜病变的进展,六角形细胞的百分比亦逐渐减少,差异有统计学意义。结论共焦显微镜检查是一种有效、无创的角膜检查方法,糖尿病对角膜每一层结构均有重要影响,角膜上皮层、角膜神经、基质细胞密度、内皮细胞密度和形态均存在改变。

objective To evaluate corneal morphological changes of subjects with type 2 diabetes. Methods 146 eyes of 120 patients who were diagnosed as type 2 diabetes, were chosen as the study group of diabetes. Other 36 eyes of 36 control subjects were included in the study. On the basis of indirect ophthalmoscopic examination and fluorescein angiography, the study group was divided into three sub-groups according to the stage of retinopathy： non-diabetic retinopathy（NDRP）, non-proliferative diabetic retinopathy（NPDR） and proliferative diabetic retinopathy（PDR）. The central corneas were scanned with confoscan 3.0. The images of stromal cells and nerves were analyzed. Results Compared with control group, neurotropic corneal epithelial keratopathy and microdots can been observed with confocal microdcopy. Corneal branch nerve fibre density of subbasal nerve plexus decreased in diabetic group compared with control group The nerve fibre density decreasing can only be seen in the PDR sub-group, while NDRP and NPDR sub-groups changed less.The proportion of patients in diabetes group with abnormal -morphology nerve fibres in mid-stroma was higher than that in control group. The cell density of anterior stroma in the PDR sub-group is lower, whereas the cell density of posterior stroma in both NPDR and PDR group is lower. Morphologic characteristics of descemet＇s membrane in type 2 diabete is shown as particular micro-fold line.There is no siginificant differences of the endothelia cell density between diabetic group and control group, but the cells of endothelium in diabetic group demonstrated a significantly higher coefficient of variation, and a decreased percentage of hexagonal cells compared to those in control group. As the development of diabetic retinopathy, the percentage of hexagonal cells decreased. The difference was statistictically significant. Conclusions Corneal confocal microscope allows rapid, noninvasive in vivo evaluation of the cornea. Diabetes can affect each layer of the cornea. Morphologic abnormalities were detected in epithelium layer, corneal nerve, stroma, endothelium layer of the patients with type 2 diabetes.