Assessment of a Fully-Automated RAPD Test as a Routine Screening Tool

The clinical log-unit relative afferent pupillary defect (RAPD)[1] has inherent variability and bias among examiners, and can be imprecise, especially with darkly-pigmented irides, anisocoria, and with small or poorly-reactive pupils. Studies have demonstrated the effectiveness of automated, infrared pupillography for measuring the RAPD[2,3,4,5,6,7] but not as a standard clinical screening tool. We compared the clinically-measured RAPD with an automated RAPiDoTM pupillometer test (Neuroptics Inc; Irvine, CA), and correlated these measurements to asymmetry of OCT retinal nerve fiber layer (RNFL) and retinal ganglion cell-inner plexiform layer (GCL) thickness.