Clinical Observation Of Early Detection Of Primary Open Angle Glaucoma By The Application Of Isolated-check Visual Evoked Potential

Objective To explore the value of qualitative pattern of isolated-check visual evoked potential(ic-VEP)in the early diagnosis of primary open-angle glaucoma(POAG),and to detect the sensitivity and specificity of ic-VEP in the clinical diagnosis of POAG,and to provide an objective and effective basis for the early and accurate diagnosis of glaucoma in practical clinical work.Methods According to the selection criteria,68 patients(82 eyes)with primary open-angle glaucoma(POAG)who were treated in our department from September2016 to March 2017 were selected as experimental group(glaucoma group)and 47cases(76 eyes)normal eyes as control group.All subjects received routine ophthalmic related tests,visual field examination,retinal nerve fiber layer thickness(RNFLT)examination by Heidelberg retinal tomography(HRT)and ic-VEP qualitative mode examination.Ic-VEP is tested with Ke Diya visual electrophysiological detector(Huzhou Meikewohua Medical Technology Co.,Ltd.),using pattern of isolated-check,detecting macular center 10 degrees of influence on ganglion cell M pathway,taking signal-to-noise ratio(SNR)as the observation index,for Ke Diya visual electrophysiology detection SNR value to "1" as the standard to measure the critical point,According to the qualitative inspection mode standard judgment:SNR?1,suggesting no pathological M-channel,judging as non-open-angle glaucoma(the result is considered negative);SNR <1,suggesting M pathways injury,judging as open angle glaucoma(the result is considered positive).Then both groups were treated to analyze ic-VEP,the defect of the visual field,RNFLT and the multivariate correlation analysisbetween ic-VEP,the visual field and RNFLT was performed.The sensitivity and specificity of ic-VEP in the diagnosis of POAG was analysis in present study.Results There was no statistical difference between the glaucoma group and the normal control group on the related parameters,such as age,diopter and central corneal thickness(P > 0.05).However,the intraocular pressure(IOP),the visual field,RNFLT and ic-VEP between two groups had statistically difference(P<0.01),It was suggested that the increase of IOP,the narrowing of the visual field,the decrease of RNFLT,and the decrease of ic-VEP SNR in the glaucoma group compared with the normal group.The correlation analysis of ic-VEP Signal-to-noise ratio(SNR)with diopter,IOP,the visual field and RNFLT in the glaucoma group showed that ic-VEP SNR was significantly associated with IOP(r=0.38,P<0.01),the visual field(r=0.36,P<0.01)and RNFLT damage(r=0.33,P<0.01),but not correlated with diopter(r=0.05,P > 0.05).The sensitivity of ic-VEP to early diagnosis of open angle glaucoma was 90.2%[88.2%~96.6%,95%CI],and the specificity was 88.2%[80.9%~95.5%,95%CI].In this study,74 eyes with SNR <1 in glaucoma group,accounting for 90.2% of the group,9 eyes with SNR <1 in the normal group,accounting for 11.8% of the group.The rate of SNR abnormality in glaucoma group was significantly higher than that in the normal group.The consistency test of ic-VEP and visual field examination and RNFLT injury showed that ic-VEP had better consistency with visual field damage(Kappa value =0.68,P < 0.01)and examination of RNFLT by HRT-III(Kappa =0.65,P < 0.01).Conclusion Ic-VEP is a functional examination.The M retinal ganglion cells in the 10 degree range of macular area are selectively stimulated by pattern of isolated-check.Ic-VEP SNR is related to the damage of the visual field and RNFLT,and is similar to the damage of the two.Ic-VEP has high sensitivity and specificity in the diagnosis of primary open-angle glaucoma.Therefore,ic-VEP is of clinical significance in the early diagnosis of primary open angle glaucoma.