Comparison of retinal nerve fiber layer thickness in patients having pseudo exfoliation syndrome with healthy adults

OBJECTIVE: To compare mean retinal nerve fiber layer (RNFL) thickness in patients having pseudo exfoliation (PXF) with normal age matched controls using spectral domain optical coherence tomography (SD-OCT). METHODS: This was a case control study conducted at Armed Forces Institute of Ophthalmology (AFIO) Rawalpindi from 12 June 2013 to 12 January 2014. Seventy eyes (Group A - 35 patients with PXF and Group B - 35 healthy age matched subjects) of more than 40 years of age were included in the study. Intraocular pressure (IOP) was measured with Goldmann applanation tonometer (GAT) and peripapillary RNFL thickness was measured in four quadrants with SD-OCT (Topcon 3D OCT-1000 Mark II) in all subjects. Data was analyzed using the SPSS version 14. RESULTS: Mean age of group A (PXF patients) was 65.63 ± 8.47 years and of group B (Healthy subjects) was 64.31 ± 6.51 years (p = 0.470). Both groups were gender matched with male preponderance (p = 0.673). Mean IOP in each group was 13.80 ± 2.59 mm Hg, and 13.49 ± 2.07 mm Hg respectively (p= 0.578). Mean average peripapillary RNFL thickness was 77.46 ± 12.17 µm in group A and 83.96 ± 10.58 µm in group B. Statistically significant differences were detected between two groups for mean average RNFL thickness (p= 0.020) and mean RNFL thickness in inferior quadrant (p=0.014). CONCLUSION: PXF patients with normal IOP and visual fields have thin RNFL as compared to healthy age matched controls. Therefore routine assessment and follow up of PXF patients with OCT may help in early diagnosis of PXF glaucoma.