Upon evaluating the potential of the temporal raphe sign on the macular ganglion cell-inner plexiform layer thickness map for discriminating glaucomatous from non-glaucomatous optic neuropathy in eyes with characteristic thinning in the affected area, researchers found that determining whether the sign appears on optical coherence tomography (OCT) macular scans can be a useful indication.

This cross-sectional study evaluated 67 eyes with glaucomatous optic neuropathy (GON) and 73 with non-glaucomatous optic neuropathy (NGON). A positive temporal raphe sign was declared in cases where there was a straight line longer than one-half of the length between the inner and outer annulus in the temporal elliptical area of the mGCIPL thickness map.

The team observed the temporal raphe sign in 61 of 67 GON eyes (91.0%) but only in 21 of 73 NGON eyes (28.8%). From this finding, they judged the diagnostic ability of the temporal raphe sign for discriminating GON from NGON to be good. They note that the diagnostic performance of their resultant model was better than that of either the temporal raphe sign or the relative afferent pupillary defect (RAPD) alone. They add that their new diagnostic model revealed the following: (1) if the temporal raphe sign is positive and the RAPD is absent, the case should be diagnosed as GON and (2) if the temporal raphe sign is absent regardless of the presence or absence of the RAPD, or both the temporal raphe sign and the RAPD are present, the case should be diagnosed as NGON.

Lee J, Kim YK, Ha A, et al. Temporal raphe sign for discrimination of glaucoma from optic neuropathy in eyes with macular ganglion cell-inner plexiform layer thinning. Ophthalmology. January 8, 2019. [Epub ahead of print].