视网膜神经纤维层厚度与糖尿病视网膜病变程度的相关性研究

Correlation between retinal nerve fiber layer thickness and severity of diabetic retinopathy

目的通过光学相干断层扫描(optical coherence tomography,OCT)仪观察具有不同视网膜病变程度的2型糖尿病患者及正常人视网膜神经纤维层(retinal nerve fiber layer,RNFL)厚度,探讨RNFL厚度与糖尿病视网膜病变(diabetic retinopathy,DR)的程度是否有相关性。方法正常对照组50人89眼,2型糖尿病患者75例130眼,按DR国际临床分型标准分为无糖尿病视网膜病变(non-diabetic retinopathy,NDR)组37例70眼、非增生性糖尿病视网膜病变(non-proliferative diabetic retinopathy,NPDR)组21例33眼、增生性糖尿病视网膜病变(proliferative diabetic retinopathy,PDR)组17例27眼,所有患者均行眼科常规检查和OCT检查;OCT测量数据包括:视盘周围360°平均及上方、下方、鼻侧和颞侧平均RNFL厚度。结果正常对照组RNFL厚度视盘360°平均为(106.80±9.28)μm、上方(130.24±16.13)μm、下方(137.50±14.12)μm、鼻侧(75.02±8.90)μm、颞侧(84.20±12.39)μm;NDR组RNFL厚度360°平均为(104.20±7.12)μm、上方(120.46±20.40)μm、下方(137.63±11.18)μm、鼻侧(74.42±6.50)μm、颞侧(84.38±12.58)μm;NPDR组RNFL厚度360°平均为(86.67±4.22)μm、上方(105.97±7.22)μm、下方(114.97±5.29)μm、鼻侧(52.93±7.86)μm、颞侧(72.81±6.91)μm;PDR组RNFL厚度360°平均为(127.92±6.44)μm、上方(154.48±9.28)μm、下方(167.22±9.59)μm、鼻侧(83.33±9.83)μm、颞侧(106.63±10.40)μm。与正常对照组相比,NPDR、PDR组各方位RNFL厚度差异均有统计学意义(均为P<0.05),NPDR组变薄而PDR组变厚;NDR组与正常对照组比较,只有360°平均及上方有统计学意义(均为P<0.05);NDR、NPDR、PDR三组间两两比较,差异均有统计学意义(均为P<0.05)。结论糖尿病患者RNFL厚度的变化与DR的程度具有相关性,NDR及NPDR患者RNFL厚度变薄提示眼底开始出现神经节细胞凋亡的可能,当RNFL厚度由薄转为增厚则提示出病变的进行性加重,对临床早期诊断及治疗具有指导意义。

Objective To measure the retinal nerve fiber layer（RNFL）thickness in patients with type 2 diabetes of different severity and normal subjects using optical coherence tomography（OCT）,and investigate the correlation between RNFL thickness and severity of diabetic retinopathy.Methods Eighty-nine eyes of 50 normal subjects and 130 eyes of 75 patients with type 2 diabetes were enrolled.Among the diabetic patients,70 eyes of 37 patients were non-diabetic retinopathy（NDR）,21 eyes of 33 patients were non-proliferative diabetic retinopathy（NPDR）and 27 eyes of 17 patients were proliferative diabetic retinopathy（PDR）.All the patients underwent routine ophthalmic examination.The mean RNFL thickness around the optic disc,as well as the superior,inferior,nasal and temporal thickness was measured by 360° OCT scanning centered on the optic disc.Results Mean,superior,inferior,nasal and temporal RNFL thickness in normal subjects were（106.80±9.28）μm,（130.24±16.13）μm,（137.50±14.12）μm,（75.02±8.90）μm and（84.20±12.39）μm,respectively.While thicknesses were（104.20±7.12）μm,（120.46±20.40）μm,（137.63±11.18）μm,（74.42±6.50）μm and（84.38±12.58）μm in NDR patients,（86.67±4.22）μm,（105.97±7.22）μm,（114.97±5.29）μm,（52.93±7.86）μm and（72.81±6.91）μm in NPDR patients,and（127.92±6.44）μm,（154.48±9.28）μm,（167.22±9.59）μm,（83.33±9.83）μm and（106.63±10.40）μm in PDR patients.Compared with normal group,there were statistical differences in the mean and all the segment of RNFL thickness in NPDR group and PDR group（all P〈0.05）.The RNFL thickness was thinner in NPDR group,while thicker in PDR group.Compared normal group with NDR group,only the mean and superior RNFL thickness had statistical difference（P〈0.05）.There were statistical differences in the RNFL thickness around the optic disc among NDR,NPDR and PDR groups（all P〈0.05）.Conclusions The changes of RNFL thickness in diabetic patients are associated with the severity of diabetic retinopathy.Reduced RNFL thickness in NDR and NPDR patients indicates the apoptosis of retinal ganglion cells.While the change in RNFL thickness from thinner to thicker suggest worsening disease severity,which is of great importance for early diagnosis and treatment of diabetic retinopathy.