The Diagnostic Performance Of Optical Coherence Tomography Angiography In Early Primary Open Angle Glaucoma

Objective:To observe and characterize macular area thickness,retinal nerve fiber layer(RNFL)thickness,ganglion cell complex(GCC)thickness,the vessel density and perfusion density in both macular area and optic disc area in patients with primary open angle glAUROComa(POAG)and normal control eyes by optical coherence tomography(OCT)and OCT angiography(OCTA),and to evaluate the diagnostic value of OCT and OCTA for early POAG patients.Methods:15 patients(23 eyes)with early POAG as observation group and 30 health people(30 eyes)as normal control group were enrolled in this cross-sectional study.OCTA-based superficial macula vessel density,superficial macula perfusion density,superficial optic disc vessel density,superficial optic disc perfusion density and spectral domain OCT(SD-OCT)-based macular area thickness,GCC thickness and RNFL thickness were measured in the two groups.Independent t-test and receiver operating characteristic curve were used for analysis.Area under the receiver operating characteristic curves(AUROC)were used to measure the diagnostic utility.Results:Among all the parameters,the optimal diagnostic utility parameter was the superficial vessel density in the macular area(except the center of the macula),and the AUROC reached 0.98.The diagnostic utility of macular area perfusion density(except the center of the macula)was similar to that of superficial vessel density in the macular area,and the AUROC was above 0.97.Followed by the diagnostic utility of vessel density in the optic disc area,the best parameter was the inner ring of the vessel density,and its AUROC reached 0.97.The diagnostic utility of perfusion density in the optic disc area was slightly lower than that of vessel density in the optic disc area.The best parameter was the central optic disc perfusion density,and its AUROC was 0.95.The SD-OCT-based diagnostic utility parameters were generally lower than that mentioned above,the top three parameters were the inferior RNFL thickness(AUROC=0.919),the superior GCC thickness(AUROC=0.919)and the inferior GCC thickness(AUROC = 0.908).Conclusion:Changes in macular thickness,GCC thickness,RNFL thickness,superficial vessel density and perfusion density in the optic disc or in macular area can be detected by OCT or OCTA in early POAG.OCTA-based superficial macular vessel density and perfusion density had the highest diagnostic utility for early POAG.The OCT-based diagnostic utility parameters were generally lower than the OCTA-based diagnostic utility parameters.