Peripapillary retinal nerve fibre thickness in patients with primary open-angle glaucoma

Abstract Background The purpose of this study was to determine the difference in peripapillary retinal nerve fiber layer (RNFL) thickness in patients with preperimetric glaucoma and open angle glaucoma (POAG) in comparison to healthy population, as well as to determine the difference in thickness of peripapillary RNFL according to progression of the disease.Methods In this study, 120 patients were included . On the basis of clinical finding four groups of patients were formed: group without glaucoma, early POAG group, moderate POAG group and group with preperimetric glaucoma. Complete ophthalmological examination, visual field and optic coherent tomography of peripapillar region of RNFL were performed. The collected data was entered into a specially created database on a personal account, and the statistical processing was done using the SPSS for Windows. Results are displayed through charts and tables.Results The results showed that the thickness of peripapillary RNFL in patients with mild POAG is lesser than in healthy subjects, and thickness in patients with moderate POAG is lesser than in patients with mild POAG, as well as in healthy subjects (59.69±10.63 μm vs 73.44±12.16 μm vs 105.57±11.34 μm). Thickness of peripapillary RNFL in patients with preperimetric glaucoma is significantly lesser than in healthy subjects (83.65±9.24 μm vs 105.57±11. 34 μm). Parameter S together with mean value of peripapillary RNFL thickness (AvgThic) is the best predictors of appearance and progression of preperimetric glaucoma. There is positive correlation between progression of glaucoma (MD value) and AvgThic. The best predictors of appearance and progression of glaucomatous disease are: AvgThic, RNFL thickness in quadrants- S, I, N; and parameters RNFL- Smax, Savg, Iavg. ROC curve has shown that the following parameters are bad markers for progression of the disease: RNFL thickness in quadrant T and Imax.Conclusions We concluded that the determination of thickness of peripapillary RNFL in patients with glaucoma using optical coherent tomography represents the method which distinguishes between patients with POAG, preperimetric glaucoma and healthy population hence it can be used in glaucoma diagnostics and follow-up.