USING ENHANCED DEPTH IMAGING OPTICAL COHERENCE TOMOGRAPHY - DERIVED PARAMETERS TO DISCRIMINATE BETWEEN EYES WITH AND WITHOUT GLAUCOMA: A CROSS-SECTIONAL COMPARATIVE STUDY.

INTRODUCTION New technologies have been developed in order to decrease interpersonal influence and subjectivity during the glaucoma diagnosis process. Enhanced depth imaging spectral-domain OCT (EDI OCT) has turned up as a favorable tool for deep optic nerve head (ONH) structures assessment. OBJECTIVE A prospective cross-sectional study was conducted to compare the diagnostic performance of different EDI OCT -derived parameters to discriminate between eyes with and without glaucoma. MATERIAL AND METHODS The following optic nerve head parameters were measured: lamina cribrosa (LC) thickness and area; prelaminar neural tissue (PLNT) thickness and area; average Bruch's membrane opening - minimum rim width (aBMO-MRW), superior (sBMO-MRW) and inferior (iBMO-MRW). Peripapillary retinal nerve fiber layer (pRNFL) thickness was also obtained. RESULTS Seventy-three participants were included. There were no significant differences between AUCs for aBMO-MRW (0.995), PNLT area (0.968) and average pRNFL thickness (0.975; p≥0.089). However, AUCs for each of these three parameters were significantly larger than LC area AUC (0.701; p≤0.001). Sensitivities at 80% specificity were: PLNT area=92.3%, aBMO-MRW=97.4% and average pRNFL thickness=94.9%. CONCLUSIONS Comparing the diagnostic performance of different EDI OCT ONH parameters to discriminate between eyes with and without glaucoma, we found better results for neural tissue-based indexes (BMO-MRW and PNLT area) compared to laminar parameters. In this specific population, these neural tissue-based parameters (including PLNT area - which was investigated by the first time in the present study) had a diagnostic performance comparable to that of the conventional pRNFL thickness protocol.