Model Study Of Structure And Function Examination In Stage Diagnosis And Follow-up Of Glaucoma

Objectives:The diagnostic efficiency of various indicators of structural and functional damages in different stages of glaucoma would be evaluated,by comparing the progress speed of the glaucoma functional and structural damages.At the same time,a new glaucoma structural damage staging system was established based on a mathematic model obtained from the ganglion cell layer thickness,and its clinical application value would be evaluated.Methods:This study included 303 eyes from 154 cases of primary glaucoma(70 males and 84 females)diagnosed by Dep.Ophthalmology in the first Affiliated Hospital of Kunming Medical University from August 2017 to February 2020.All eyes were tested by reliable standard automatic perimeter(SAP)and optical coherence tomography(OCT).The diffuse defect parameters,such as MD,average RNFL,and average GCL,were used to stage the glaucoma on the basis of the H-P-A method.The local defect parameters,such as the<2%,<1%and<0.5%defect points of the visual field,RNFL and GCL from OCT in the corresponding superior and inferior halves,were used to stage the glaucoma on the basis of the USP-GVFSS method.These results were performed the correlation analyses,and the analysis of specificity and sensitivity.On the basis of the visual field GSS2 staging system and the OCT-RNFL GSS staging system,another preliminary structure damage staging system based on GCL progress suitable for Chinese glaucoma,OCT-GCL GSS staging system,was obtained,and further comparison and verification of the correlation and difference between OCT-GCL GSS staging system and the former two systems were completed in order to evaluate its application value in glaucoma progress analysis.Results:The results of OCT and SAP were used in 303 eyes from 154 cases,including 198 eyes with RNFL+VF and 105 eyes with RNFL+GCL+VF.1.As for diffuse defect indices,in the analysis of whole course of glaucoma,the change rate of average GCL was faster than the one of average RNFL(P<0.05)and MD(P<0.05),and the change rate of average RNFL was faster than the one of MD(P<0.05).In the analysis of early course of glaucoma,the change rate of average RNFL,average GCL and MD were consistent with those analyses in the whole course of glaucoma(P<0.05).In the analysis of middle course of glaucoma,the change rate of average RNFL was faster than the one of average GCL(P<0.05)and MD(P<0.05),but there was no linear correlation between the change rates of average GCL and MD(P>0.05).In the analysis of late course of glaucoma,the change rate of average GCL was faster than the one of average RNFL(P<0.05)and MD(P<0.05),but there was no linear correlation between the change rates of average RNFL and MD(P>0.05).2.As for local defect indices,in the analysis of whole course of glaucoma,the change rate of superior RNFL mean was equivalent to the one of superior GCL(P<0.05),but the one of inferior RNFL was faster than the one of inferior GCL(P<0.05).In the analysis of early course of glaucoma,the change rate of superior RNFL was much slower than the one of superior GCL(P<0.05),but the one of inferior RNFL was faster than the one of inferior GCL(P<0.05).In the analysis of middle course of glaucoma,the change rate of inferior RNFL was much faster than the one of inferior GCL(P<0.05),but there was no linear correlation between the change rates of superior RNFL and superior GCL(P>0.05).In the analysis of late course of glaucoma,the rate of superior RNFL was much slower than the one of superior GCL(P<0.05),but there was no linear correlation between the change rates of inferior RNFL and inferior GCL(P>0.05).3.Specificity and sensitivity analysis:For distinguishing glaucoma visual field damages between early and middle stages,the specificity and sensitivity of average RNFL were better than average GCL(P<0.05),and the same in superior and inferior RNFL to corresponding GCL(P<0.05).On the other hand,for distinguishing glaucoma visual field damages between middle and later stages,the specificity and sensitivity of average GCL were better than average RNFL(P<0.05),and the same in superior and inferior GCL to corresponding RNFL(P<0.05).4.OCT-GCL GSS staging system:Based on the location of GCL defects(superior,inferior or diffuse)and the linear regression equations,two straight lines were obtained to distinguish the superior local,inferior local or diffuse defects.On the basis of Mills method of six stages(0-5 stages)in MD,four curves were produced by nonlinear regression equations,and 1-5 grades were distinguished.OCT-GCL GSS system,visual field GSS2 system and OCT-RNFL GSS system had their own optimal applicability in each stage of glaucoma.Conclusions:In the early and late stages of glaucoma,the changes of GCL were better than those of RNFL,which could be used as the first observation index for the structural progress in early and late stages of glaucoma.In the middle stage of glaucoma,the changes of RNFL were better than those of GCL,which could be used as the first observation index for the structural progress in middle stage of glaucoma.Although the OCT-GCL GSS staging system lacked the boundary between borderline and stage 0,stage 0 and stage 1,it had the preliminary functions of staging and follow-up for glaucoma,which could be used to effectively analyze the glaucoma progress in the early and late stages.