Title: Diagnostic utility of RNFL Thickness and Macular GCC Thickness in Primary Open Angle Glaucoma using Spectral Domain Optical Coherence Tomography in South Indian patients
Authors: Neeta Sidhan, Preethi Sara George, PS Girija Devi
DOI: https://dx.doi.org/10.18535/jmscr/v5i6.21
Abstract
Purpose: To evaluate and compare the diagnostic abilities of peripapillary retinal nerve fibre layer thickness (RNFL) parameters and macular Ganglion cell complex (GCC) parameters in the early detection of Glaucoma using high resolution spectral domain Optical Coherence Tomography(OCT).
Materials and Methods: Fifty eyes with Primary open angle glaucoma (POAG) and 50 normal eyes in the age group 35-70 years underwent Optical Coherence Tomographic evaluation. Statistical analysis was done using SPSS version11. Receiver operating characteristic curves (ROC) along with sensitivity at fixed specificity were studied for each tomographic parameter. Correlation of Tomographic data with visual field defects was evaluated by linear regression analysis.
Results: The visual field parameters of glaucoma patients showed a mean deviation value of (-6.1 ± 3.5) and pattern standard deviation value of (5.3 ± 3.3). Significant differences between glaucoma and normal subjects were found for all tomographic parameters. The best parameters based on Receiver operating characteristic curves and sensitivity at 95% specificity were RNFL-Average (AROC, 0.960; sensitivity, 80%) and GCC-Superotemporal quadrant (AROC, 0.912; sensitivity, 80%).
Conclusions: Both retinal nerve fibre layer thickness parameters and macular Ganglion cell complex parameters showed good diagnostic abilities in the diagnosis of early glaucoma using the spectral domain Optical Coherence Tomography. Better performance of macular parameters (compared to previous observations using older -Time Domain- Optical Coherence Tomography) were noted in the current study, however they did not outperform RNFL parameters.
Keywords: RNFL Thickness, GCC Thickness, SD OCT, Glaucoma.
