早期糖尿病视网膜病变患者黄斑神经节细胞层厚度及视盘参数的变化

Alterations of macular ganglion cell layer thickness and optic disc parameters in patients with early diabetic retinopathy

目的:使用Cirrus HD-OCT比较早期糖尿病视网膜病变患者和健康对照者之间的视盘参数、视盘周围视网膜神经纤维层(pRNFL)厚度和黄斑神经节细胞层(mGCL)厚度改变。方法:横断面比较研究。选取45例无糖尿病视网膜病变(NDR)、52例轻度非增殖期糖尿病视网膜病变(NPDR)及55例中度NPDR的2型糖尿病患者和64例年龄匹配的健康对照者纳入本研究。采集患者的空腹血糖、糖尿病病程、糖化血红蛋白及既往史。通过Cirrus HD-OCT测量视盘参数(即双眼RNFL厚度对称性百分比、盘沿面积、视盘面积、杯盘比、杯容积)、pRNFL厚度和mGCL厚度。组间比较采用单因素方差分析。结果:与健康对照组比较,NDR、轻度NPDR、中度NPDR组双眼RNFL厚度对称性百分比、盘沿面积明显降低,平均C/D、垂直C/D明显增加(均P<0.05)。与健康对照组比较,NDR、轻度NPDR、中度NPDR组患眼视盘周围各象限(上方、颞侧、下方、鼻侧)及平均RNFL厚度和黄斑(平均、最小、上方、颞上方、颞下方、下方、鼻上方、鼻下方)GCL厚度显著变薄(均P<0.05)。结论:与健康对照者相比,早期DR患者的双眼RNFL厚度对称性百分比、盘沿面积、pRNFL和mGCL厚度明显降低,而杯盘比显著增高。本研究结果支持DM导致内层视网膜神经退行性变化的说法,即使在无明显微血管病变的T2DM患者中。

AIM:To compare the changes of optic disc parameters,peripapillary retinal nerve fibers layer (pRNFL) thickness and macular ganglion cell layer (mGCL) thickness among patients with early diabetes retinopathy and healthy controls by Cirrus HD-optical coherence tomography(OCT).METHODS:In this cross-sectional comparative study,45 non-diabetic retinopathy (NDR),52 mild nonproliferative diabetic retinopathy (NPDR),55 moderate NPDR with type 2 diabetes mellitus (T2DM) and 64 age-matched healthy controls were included.The fasting blood glucose (FBG),duration of diabetes,glycosylated hemoglobin (HbA1c) and past history of the patients were collected in detail.Optic disc parameters ( i.e.,binocular RNFL thickness symmetry percentage,rim area,optic disc area,cup-to-disc ratio,cup volume),pRNFL thickness and mGCL thickness were measured by Cirrus HD-OCT.The comparison of different groups was performed by one-way analysis of variance.RESULTS:Compared with the control group,the binocular RNFL thickness symmetry percentage and rim area were significantly decreased,while the average C/D and vertical C/D were significantly increased in the NDR group,mild NPDR group and moderate NPDR group (all P <0.05).Compared with the control group,the peripapillary RNFL thicknesses (superior,temporal,inferior,nasal) and macular GCL thickness (average,minimum,superior,supero-temporal,infero-temporal,inferior,supero-nasal,and infero-nasal) became thinner in the NDR group,mild NPDR group,and moderate NPDR group (all P <0.05).CONCLUSION:Patients with early DR have significantly decreased binocular RNFL thickness asymmetry,rim area,pRNFL and mGCL thickness,while they have significantly increased cup-to-disc ratio when compared to healthy controls.The results support the statement that DM causes inner retinal neurodegenerative changes even in T2DM patients without overt microangiopathy.