不同程度2型糖尿病视网膜病变患者视网膜神经纤维层厚度的变化和比较

Measurement and comparison of retinal nerve fiber layer thickness in different stages of diabetic retinopathy patient with type 2 diabetes

背景糖尿病视网膜病变（DR）是不可逆盲的主要原因之一。近来研究发现，视网膜神经细胞的病变是DR病理改变的一部分，发生在DR发病之前，因此了解2型糖尿病患者视网膜神经细胞的病理变化对DR的防治有重要意义。目的应用GDxVCC系统测量2型糖尿病患者不同DR分期视网膜神经纤维层（RNFL）厚度的改变。方法纳入北京协和医院眼科确诊的2型糖尿病患者48例96眼，依据检眼镜检查结果和荧光素眼底血管造影（FFA）结果分为DR临床前期组（NDR组）、非增生期糖尿病视网膜病变组（背景期）（BDR组）、增生型糖尿病视网膜病变组（PDR组）和全视网膜激光光凝组（PRP组），年龄和性别匹配的24名正常受试者作为正常对照组。应用GDxVCC系统测量受试者视网膜颞上、颞下、鼻上、鼻下（TSNIT）4个象限RNFL厚度，参数包括TSNIT平均值、上方平均值、下方平均值、TSNIT标准差及神经纤维指数，各组间的测量值进行比较。结果NDR组、BDR组、PDR组及PRP组患者RNFL的TSNIT平均值分别为（56．54±5．28）、（56．92±6．49）、（53．04±6．14）、（53．17±9．30）μm，正常对照组为（59．04±4．57）μm；与正常对照组相比，PDR组及PRP组患者RNFL的TSNIT平均值、上方平均值、下方平均值、TSNIT标准差明显降低，神经纤维指数增高，差异均有统计学意义（PDR组：P=0．002、0．000、0．002、0．000、0．001；PRP组：P=0．002、0．000、0．001、0．000、0．000），而NDR组、BDR组RNFL的TSNIT平均值、上方平均值、下方平均值、TSNIT标准差均降低，神经纤维指数增高，但RNFL参数差异均无统计学意义（P=0．187、0．235、0．333、0．106、0．202；P=0．262、0．063、0．072、0．098、0．062）。结论2型糖尿病患者在眼底及FFA检查尚未发现DR时即可出现RNFL变薄，PDR及接受PRP治疗后的患者RNFL变薄．提示糖尿病患者视网膜神经细胞及其轴突出现蛮件和丢失。

Background Diabetic retinopathy （DR） is one of the leading causes that result in adult irreversible blindness in many countries. Recent researches suggest that neurodegeneration is an important component of DR. To realize the disease process of retinal neutron is very important for prevention and treatment on DR. Objective This study was to investigate the change of retinal nerve fiber layer thickness in patients with type 2 diabetes mellitus. Methods Ninety-six eyes of 48 patients with type 2 diabetes mellitus were enrolled in Peking Union Medical College Hospital. The patients were assigned into non-diabetic retinopathy（NDR） group,background diabetic retinopathy（BDR） group, proliferative diabetic retinopathy （PDR） group and panretinal photocoagulation （PRP） group based on the fundus finding and fundus fluorescein angiograpby（FFA）, and 24 normal subjects with matched age were included as control group. RNFL thickness was measured by GDxVCC system,including temporal, superior, nasal, inferior, total, （TSNIT） average, superior average, inferior average, TSNIT standard deviation and nerve fiber indication. The datas of the RNFL thickness were analyzed and comparison among different groups by one-way analysis of variance and Student Newman Keuls test. Results The TSNIT averages of the NDR group,BDR group, PDR group and PRP group were （56.54±5.28）, （56.92±6.49）, （53.04±6.14） and（53.17±9.30） μm, respectively,while that of the control group was （ 59.04 ± 4.37 ） μm. The TSNIT average, superior average, inferior average,TSNIT standard deviation of the PDR group and PRP group compared with control group were significantly decreased, and the nerve fiber indication of the PDR group and PRP group was significantly increased （ P = 0. 002, 0. 000,0. 002,0. 000,0. 001 ;P=0. 002,0. 000,0. 001,0. 000,0. 000）. Compared with the control group,the TSNIT average,superior average, inferior average, TSNIT standard deviation were insignificantly decreased, and the nerve fiber indication was insignificantly increased in the NDR group and BDR group （ P = 0. 187,0. 235,0. 333,0. 106, 0. 202;P= 0. 262,0. 063,0. 072,0. 098,0. 062）. Conclusions The decline of the RNFL thickness appears prior to DR findings. The RNFL thinning of PDR and PRP patients suggests the degeneration of neurons and atrophy of axonal. The neurodegeneration is an important component of DR.