OCT检测视盘形态及视网膜神经纤维层厚度在开角型青光眼早期诊断中的应用

Evaluation of retinal nerve fiber layer thickness and optic disc morphous by optical coherence tomography in early diagnosis of primary angleopen glaucoma

目的采用RTVue OCT测量正常人和青光眼患者的视网膜神经纤维层(retinal nerve fiber layer,RNFL)厚度以及视盘的各项参数并进行分析,探讨频域OCT在青光眼诊断中的作用。方法收集正常人40例(40眼)、原发性开角型青光眼(primary open-angle glaucoma,POAG)早中期患者30例(30眼)、POAG晚期患者38例(38眼),OCT测量所有研究对象视盘各参数、视盘各象限的RNFL厚度、平均RNFL厚度。对各参数与视野平均缺损(mean defect,MD)值进行相关分析,对检测结果进行评价。结果 OCT检测结果表明,正常组和POAG早中期组、POAG晚期组上方、颞侧、下方、鼻侧象限RNFL厚度和平均RNFL厚度的差异均有统计学意义(均为P=0.000),各组RNFL厚度从厚到薄依次为视盘下方、上方、颞侧、鼻侧象限。在视盘形态参数中,正常组、POAG早中期组和POAG晚期组患者视杯面积、盘沿面积、盘沿容积、视杯容积、视盘容积、杯盘面积比、水平杯盘比以及垂直杯盘比之间的差异均有统计学意义(均为P=0.000),组间两两比较差异也均有统计学意义(均为P<0.05);而视盘面积差异无统计学意义(P=0.497)。对POAG患者的检测表明,视盘上方、颞侧、下方象限RNFL厚度以及平均RNFL厚度与视野MD值之间存在着负相关关系(r=-0.455、-0.211、-0.493、-0.425,均为P<0.05),而鼻侧象限RNFL厚度与视野MD值无相关性(r=-0.106,P>0.05);视盘参数中,视杯面积和杯盘面积比与视野MD值呈正相关(r=0.057、0.394,均为P<0.05),而盘沿面积、盘沿容积和视盘容积与视野MD值呈负相关(r=-0.275、-0.306、-0.418,均为P<0.05)。结论 RNFL厚度和视盘各参数是早期青光眼的敏感指标,RTVue OCT检测RNFL厚度和视盘参数有助于青光眼早期诊断。

Objective To evaluate the clinical value of retinal nerve fiber layer （RNFL） and optic disc tomogmphy by RTVue OCT in normal and glaucomatous eyes. Methods This study included 40 eyes of 40 normal subjects, 30 eyes of 30 patients with early and moderate primary open-angle glaucoma （POAG） ,38 eyes of 38 patients with advanced POAG. The optic disc parameters and regional and average RNFL thick- ness were measured in all the subjects with RTVue OCT. The correlation between the parameters and the mean defect （MD）of the visual field in glaucomatous eyes was analyzed. Results The regional （ temple, nasal, superior, inferior） and average RNFL thickness obtained by RTVue OCT showed significant difference in normal, early and moderate,advanee glaucomatous eyes （ all P = 0 000 ）.The regional RNFL, thickness from thick to thin in three groups was inferior, superior, temporal and nasal. There was statistical difference in optic disc parameters such as cup area, rim area, rim volume, cup volume, nerve head volume, cup/disc area ratio, cup/disc horizontal ratio and cup/disc vertical ratio among early and moderate POAG group, advanced POAG group and normal group （ all P = 0.000）, while there was no statistical difference in disc area among three groups （P = 0.497）. In POAG group, the superior, temporal and inferior RNFL thickness parameters by RTVue OCT were negative correlated with MD of the visual field （ r = -0.455, -0.211, -0.493, -0.315, all P 〈 0.05 ）, while the nasal RNFL thickness by RTVue OCT was not correlated with MD of the visual field（r = -0.106 ,P 〉 0.05 ）. Optic disc parameters by RTVue OCT including cup area, cup/disc area ratio were positive correlated with MD of the visual field （ r = 0.057,0. 394, P 〈 0.05 ）, while parameters including rim area, volume and nerve head volume were negative correlated with MD of the visual field（ r = - 0.275, - 0. 305, - 0.418, all P 〈 0. 05）. Conelusion RNFL thickness and each optic disc parameter are sensitive indexes for early POAG, and RNFL thickness and optic disc parameter detected by RTVue OCT is helpful in the early diagnosis of glaucoma.