| Background: Glaucoma is characterized by damage to retinal ganglion cells(RGCs)and subsequent visual field defects.High resolution coherence tomography(Cirrus HD-OCT)can accurately and reliably quantify the thickness of ganglion cell layer-inner plexiform layer(GCIPL)in macular region.Objective:To investigate the diagnostic value of macular GCIPL thickness in chronic primary angle closure glaucoma(CPACG).Method:This study included 51 patients(86 eyes)with chronic primary angle closure glaucoma and 21 healthy volunteers(42 eyes).Cirrus HD-OCT was used to detect the thickness of GCIPL in macular area,retinal nerve fiber layer around optic disc(RNFL)and parameters of optic disc(ONH)area in all subjects.Humphrey visual field was also examined.CPACG was divided into early,middle and late stages according to the mean defect(MD)value of visual field examination.The parameters of upper GCIPL and lower GCIPL,upper nasal GCIPL,lower nasal GCIPL,upper temporal GCIPL,lower temporal GCIPL,average GCIPL,minimum GCIPL,upper RNFL,lower RNFL,nasal RNFL,temporal RNFL,average RNFL and optic disc were compared in each group.The diagnostic efficiency of GCIPL thickness,RNFL thickness and optic disc parameters for CPACG was evaluated by using area under curve(AUC)and ROC curve of working characteristics of subjects.Results:The thickness of GCIPL in the normal group was significantly different from that in the early,middle and late groups(P < 0.05).The thickness of RNFL in normal group was different from that in early group except nasal side(P < 0.05).There was significant difference in RNFL thickness between the normal group and the late group(P < 0.05).There was no difference in optic disc parameters between normal group and early group.There were significant differences in the parameters of optic discs between the middle and late stages of normal group(P < 0.05).The thickness of GCIPL,RNFL and optic disc parameters were correlated with MD values.In the early glaucoma group,the highest AUC value was the lowest GCIPL value,followed by the average GCIPL value.In the early stage group,except that the AUC value of RNFL in nasal side was lower than 0.7,the RNFL in other quadrants showed higher AUC value,and the AUC value of the average RNFL was the highest.In the early glaucoma group,the AUC values of the optic disc parameters were lower,and the AUC values of the rim area were the highest.The quadrants of RNFL and GCIPL in the medium-term glaucoma group showed higher AUC values,the highest being the minimum of GCIPL.In the mid-term group,the area along the disc edge and cup volume showed higher AUC values,while the AUC values of the remaining parameters were lower.The AUC value of RNFL in the nasal side was 0.971 in the advanced glaucoma group,and the RNFL and GCIPL in the other quadrants were 1.0.The AUC values of disk edge area and cup volume are higher in optic disc parameters,while the AUC values of the remaining parameters are relatively lower.Conclusions:GCIPL is a sensitive index for glaucoma diagnosis.The minimum GCIPL should be observed in the early diagnosis of glaucoma.RNFL is a reliable basis for the diagnosis of glaucoma.The sensitivity of optic disc parameters to glaucoma diagnosis is relatively poor. |
