Retinal nerve fiber layer and ganglion cell complex thickness analysis in patients having relative afferent pupillary defect

Purpose: To determine the retinal nerve fiber layer (RNFL) thickness and ganglion cell complex (GCC) thickness in patients having relative afferent pupillary defect (RAPD) measured by optical coherence tomography (OCT). Methods: This cross-sectional study was conducted on 30 patients with posterior segment disease and glaucoma presenting with RAPD. The control group comprised 30 patients with the aforementioned diseases without RAPD. RAPD was graded using neutral density filters placed over the unaffected eye. Peripapillary RNFL thickness and macular GCC were measured using the Cirrus HD-OCT machine. Results: There were 45 males and 15 females. There was a statistically significant (P < 0.05) difference in the mean of average RNFL thickness in patients having RAPD (64.73 +/- 15.16 mu m in the affected eyes) as compared to sick control (82.73 +/- 11.33 mu m in the affected eyes). It was further observed that there was a decrease in RNFL thickness with advancing grades of RAPD. There was a statistically significant (P < 0.05) difference in the mean of average GCC thickness in patients having RAPD (51.57 +/- 14.96 mu m in the affected eyes) as compared to sick control (76.36 +/- 8.06 mu m in the affected eyes). Conclusion: Our study suggests that there is a significant reduction in RNFL thickness and GCC thickness in RAPD patients as compared to the sick control group.