神经节细胞复合体厚度检测在原发性开角型青光眼中的诊断价值

背景 青光眼以损害视网膜神经节细胞(RGCs)继而出现视野缺损为特征,高分辨率频域OCT(SD-OCT)可以准确可靠地定量分析黄斑区视网膜神经节细胞复合体(GCC)厚度. 目的 探讨黄斑区GCC厚度对原发性开角型青光眼(POAG)的诊断意义.方法 采用前瞻性诊断试验研究设计.于2015年11月至2016年4月在北京同仁医院连续纳入POAG患者70例和30名健康志愿者,应用RTVue SD-OCT对70例POAG患者和30名正常对照者进行黄斑区GCC厚度和视盘周围视网膜神经纤维层(RNFL)厚度检测,并行Humphrey视野检查,均纳入受检者的右眼进行统计.根据视野检查的平均缺损(MD)值将POAG分为早期、进展期和晚期,对各组受检眼平均GCC、上方GCC和下方GCC、平均RNFL、上方RNFL、下方RNFL、局部丢失体积(FLV)和整体丢失体积(GLV)进行比较;评估POAG患者GCC厚度、RNFL厚度与视野MD值的关系,采用曲线下面积(AUC)和受试者工作特征ROC曲线评价GCC厚度和RNFL厚度对POAG的诊断效率. 结果 与正常对照组比较,早期POAG组、进展期POAG组和晚期POAG组的平均GCC、上方GCC、下方GCC、平均RNFL、上方RNFL和下方RNFL均明显降低,FLV和GLV均明显升高,各组间总体比较差异均有统计学意义(均P＜0.001);与早期POAG组比较,进展期POAG组和晚期POAG组受检眼平均GCC值和平均RNFL厚度值均明显下降,GLV值明显增加,差异均有统计学意义(均P＜0.05);晚期POAG组受检眼上方RNFL厚度值明显低于早期POAG组,差异有统计学意义(P=0.003);晚期POAG组受检眼上方GCC值明显低于早期POAG组和进展期POAG组,差异均有统计学意义(均P＜0.001);与早期POAG组比较,进展期POAG组和晚期POAG组受检眼下方GCC和下方RNFL厚度值明显下降,FLV明显增加,差异均有统计学意义(均P≤0.01).POAG患者平均GCC、上方GCC和下方GCC、平均RNFL、上方RNFL和下方RNFL与MD值均呈线性正相关(r=0.624、0.583、0.601、0.571、0.447、0.537,均P＜0.001);POAG患者平均GCC与平均RNFL、上方GCC与上方RNFL以及下方GCC与下方RNFL均呈线性正相关(r=0.648、0.630、0.602,均P＜0.001).平均GCC、上方GCC、下方GCC、FLV、GLV、平均RNFL、上方RNFL和下方RNFL的AUC值分别为0.965、0.924、0.979、0.985、0.980、0.990、0.979和0.992(均P＜O.001).GCC参数中FLV与下方RNFL的AUC值比较,差异无统计学意义(P＞0.05). 结论 POAG患者下方GCC厚度更容易受到损伤,GCC参数中FLV和GLV是诊断POAG的敏感指标,GCC厚度可以作为诊断和判断POAG病情进展的有效指标.

Diagnostic capability of ganglion cell complex thickness in primary open angle glaucoma

Background Glaucoma is characterized by loss of retinal ganglion cells (RGCs) followed by visual field defects.Spectral domain OCT(SD-OCT) enabled more precise and quantitative assessments of macular ganglion cell complex (GCC) thickness.Objective This study was to evaluate the diagnostic ability of GCC thickness in identifying primary open angle glaucoma (POAG).Methods A prospective study was performed.Seventy POAG patients and 30 healthy volunteers were enrolled in Beijing Tongren Hospital from November 2015 to April 2016.Macular GCC thickness and peripapillary retinal nerve fiber layer (RNFL) thickness were measured with RTVue SD-OCT,and Humphrey perimetry was performed on the eyes.The patients were assigned to the early stage POAG group,advanced POAG group and later stage POAG group based on the mean defect (MD) of visual field.The average,superior,inferior GCC and RNFL,focal loss volume (FLV),and global loss volume (GLV) were measured and compared among the groups.The correlations between GCC thickness or RNFL thickness with MD were evaluated in the POAG eyes.The discrimination capabilities of GCC thickness or RNFL thickness were assessed and compared by using areas under the receiver operating characteristic (ROC) curves (AUC).Results Compared with the normal control group,the average,superior,inferior GCC thickness and RNFL values were evidently reduced,the FLV and GLV were significantly increased in the early stage POAG group,advanced POAG group and later stage POAG group (all at P＜0.001).Compared with the early stage POAG group,the average GCC and RNFL thickness values were significantly reduced,and GLV was increased in the advanced POAG group and later stage POAG group (all at P＜0.05).In the later stage POAG group,superior RNFL was thinner than that in the early stage POAG group (P =0.003).The superior GCC value were lower in the later stage POAG group than that in the early stage POAG group and advanced POAG group (all at P＜0.001).Compared with the early stage POAG group,the inferior GCC and RNFL thicknesses were decreased and the FLV was increased in the advanced POAG group and the later stage POAG group (all at P≤0.01).Linear positive correlations were found between average GCC,superior GCC,inferior GCC,average RNFL,superior RNFL or inferior RNFL and MD (r =0.624,0.583,0.601,0.571,0.447,0.537,all at P＜0.001),and the positive correlations were also seen between average GCC and average RNFL,between superior GCC and superior RNFL or between inferior GCC and inferior RNFL (r =0.648,0.630,0.602,all at P＜0.001).The AUCs were 0.965,0.979,0.924,0.985,0.980,0.990,0.979 and 0.992 in the average GCC,superior GCC,inferior GCC,FLV,GLV,average RNFL,superior RNFL and inferior RNFL,with the largest AUCs in the FLV and inferior RNFL thickness.No significant difference was found in the AUC between FLV and inferior RNFL thickness (P＞0.05).Conclusions Inferior GCC is more susceptible to glaucomatous damage.FLV and GLV from GCC pattern parameters are sensitive indicators for diagnosis of POAG.GCC thickness could be a valid structural parameter for detecting glaucoma and can be used as a marker in glaucoma assessment.