DIAGNOSTIC PERFORMANCE OF OPTICAL COHERENCE TOMOGRAPHY MACULAR GANGLION CELL-INNER PLEXIFORM LAYER & RETINAL NERVE FIBER LAYER THICKNESS IN GLAUCOMA SUSPECT AND EARLY GLAUCOMA

Abstract

ABSTRACT PURPOSE: To evaluate the glaucoma diagnostic performance of ganglion cell inner plexiform layer (GCIPL) parameters and retinal nerve fiber layer (RNFL) parameters measured with cirrus HD- Optical Coherence Tomography(OCT). METHOD: A total of 188 eyes were included in this study. 49 eyes of healthy controls, 70 glaucoma suspect eyes and 69 early glaucomatous eyes. Complete ophthalmic examination was done including visual field test with Humphrey field analyzer and optical coherence tomography scanning of GCIPL and RNFL in different quadrants.The area under the receiver operating characteristic curve (AUROC), sensitivity and specificity of each parameter was calculated to provide diagnostic ability between normal controls, glaucoma suspects or early glaucoma. RESULT: GCIPL and RNFL parameters had strong power in discriminating early glaucoma from healthy controls with all having area under receiver operating curve (AUROC) of above 0.76. Of all the GCIPL and RNFL parameters, the only variable that could discriminate between glaucoma suspect and healthy controls was the combined parameter by OR-logic approach . Of all the parameters, the average and nasal RNFL parameters had the strongest power in discriminating between the two with AUROC of 0.81. All parameters had an overall good diagnostic performance with excellent sensitivity but the specificity was relatively poor. The combined parameter had the best specificity (62.2%) with excellent sensitivity (93.5%). CONCLUSION: The Or-logic combination of GCIPL and RNFL provides better diagnostic performance than single GCIPL, RNFL or ONH parameter. DISSEMINATION OF RESULT- The research findings will be submitted to a reputable Journal for publication at the end.