Measurement of the Inner Retinal Layers of Megalopapilla by Optical Coherence Tomography

The main purpose of this study was to assess the differences in the peripapillary retinal nerve fiber layer (pRNFL) and ganglion cell-inner plexiform layer (GCIPL) thicknesses between subjects with megalopapilla (MP) and those with large (physiological) cup discs (LCD) measured by spectral-domain optical coherence tomography. The secondary purpose was to determine whether pRNFL and GCIPL thicknesses increase with the optic nerve head (ONH) area. This cross-sectional study included 184 eyes (92 eyes with MP and 92 eyes with LCD). The subjects with LCD were used as sex-and-age-matched controls. All subjects were imaged using the Cirrus HD-OCT system. Macula and pRNFL thickness maps were obtained for all subjects. The inferior quadrant pRNFL thickness was higher in the MP group than in the LCD group (P