The Application Of Optical Coherence Tomography In The Early Diagnosis Of Primary Open Angle Glaucoma

Objective:To study the value of using optical coherence tomography(OCT) for the early diagnosis of primary open angle glaucoma(POAG).Normal eyes, ocular hypertension with risk factor, ocularhypertension without risk factor and primary open angle glaucoma wereexamined with OCT to obtain the peripapillary retinal nerve fiber layer (RNFL)and the macular thickness.Through the comparative study, this paper discussesthe above parameters for differences between groups.Compare RNFL andmacular thickness in the early diagnosis of POAG.Methods:OCT was used to measure the RNFL and the macular thicknessin30cases (40eyes) normal persons,35cases (40eyes)ocular hypertensionwith risk factor,38cases (40eyes)ocular hypertension without risk factor and38cases (40eyes) POAG. Parameters including superior, inferior, nesal andtemporal quadrants and the mean RNFL Thickness. Also includes macularsuperior, inferior and the total average retinal thickness. All data wereprocessed by SPSS13.0. The age of the above four groups were analyzed byvariance analysis, diopte rwere analyzed by non parametric test, gender ratiowere analyzed by chi-square test. We analyze peripapillary retinal nerve fiberlayer thickness and macular thickness with variance analysis. According tothe diagnostic criteria of clinical primary open angle glaucoma, select normalpersons and primary open angle glaucoma, establish the receive operatorcharacteristic curve of RNFL thickness and macular thickness, the power ofeach parameter to detect early primary open angle glaucoma was evaluated byarea under the receive operator characteristic curve(AROC).Results:1The gender ratio of normal eyes, ocular hypertension with risk factor,ocular hypertension without risk factor and primary open angle glaucoma were analyzed by chi-square test, there was no statistically significantdifference（p﹥0.05）;2The age of normal eyes, ocular hypertension with risk factor, ocularhypertension without risk factor and primary open angle glaucoma wereanalyzed by variance analysis，there was no statistically significant difference（p﹥0.05）;3The diopter of normal eyes, ocular hypertension with risk factor, ocularhypertension without risk factor and primary open angle glaucoma wereanalyzed by chi-square test, there was no statistically significant difference（p﹥0.05）;4Each quadrant and mean RNFL thickness of normal eyes, ocularhypertension with risk factor, ocular hypertension without risk factor andprimary open angle glaucoma were compared, the overall difference wasstatistically significant (p﹤0.05). Multiple comparisons between groups,thedifference between normal eyes and ocular hypertension without risk factorhave no statistically significant （p﹥0.05）. Comparison between the othergroups, the difference was statistically significant;5Each partition and average macular thickness of normal eyes, ocularhypertension with risk factor, ocular hypertension without risk factor andprimary open angle glaucoma were compared, the overall difference wasstatistically significant (p﹤0.05).Multiple comparisons between groups,thedifference between normal eyes and ocular hypertension without risk factorhave no statistically significant （p﹥0.05）. Comparison between the othergroups, the difference was statistically significant;6For early diagnosis of POAG, the AROC of superior, inferior, nesal andtemporal quadrants and the mean RNFL thickness are0.951,0.948,0.916,0.950,0.969. The AROC of macular superior, inferior and the total averageretinal thickness are0.891,0.821,0.866. The mean RNFL thickness whichhave the greatest diagnostic value. Overall, the diagnostic value of RNFL isgreater than the macular retinal thickness.Conclusion: Optic nerve damage of early glaucoma can be observed and quantitatively measuring by optical coherence tomography. OCT has clearsignificant for the early diagnosis of POAG, which can provides importantreference for the early treatment of ocular hypertension with risk factor.