The new Bruch’s membrane opening – minimum rim width classification improves optical coherence tomography specificity in tilted discs

BACKGROUND AND OBJECTIVE To investigate and compare the false-positive (FP) diagnostic classification of the Bruch's membrane opening - minimum rim width (BMO-MRW) and retinal nerve fiber layer (RNFL) thickness in healthy eyes with tilted optic disc. MATERIALS AND METHODS Fifty healthy eyes of 30 participants with tilted optic disc underwent BMO-MRW and RNFL scanning using Spectralis and macular Cirrus optical coherence tomography (OCT) scans. RESULTS The overall FP rate was significantly lower using BMO-MRW map compared with both RNFL map by Spectralis (8% vs 62%, respectively, P<0.001) and ganglion cell analysis (GCA) map by Cirrus (8% vs 50%, respectively, P<0.001). Specificity was significantly higher using BMO-MRW than RNFL in eyes with low (89.7% vs 41.4%, P<0.001) and moderate myopia (95.2% vs 33.3%, P<0.001). CONCLUSION OCT-derived BMO-MRW analysis provides significantly greater specificity than RNFL in tilted disc irrespectively of the refractive error, and it is more specific than GCA analysis in tilted disc with moderate myopia.