Evaluation of changes in retinal fiber layer thickness in pseudoexfoliation syndrome using spectral domain optical coherence tomography

Abstract

Background: Pseudoexfoliation syndrome (PEX) is a disorder characterized by the progressive accumulation of fibrillary extracellular deposits in several ocular tissues including the iris, anterior chamber angle, lens capsule, and zonules. It is an independent risk factor for glaucomatous optic nerve damage. Retinal nerve fiber layer thickness analysis using optical coherence tomography (RNFL-OCT) is a documented investigative tool to detect preperimetric glaucoma and helps to detect glaucoma early. Objective: The objective of this study was to evaluate the retinal nerve fiber thickness in eyes with PEX using OCT and to compare them with healthy controls. Materials and Methods: This prospective cross-sectional control study was conducted at GMC, Srinagar, in which retinal nerve fiber thickness 50 patients of PEX and 50 healthy control subjects were compared using Cirrus spectral domain OCT (Carl Zeiss). Complete ocular and physical examination was also done in all subjects. Results: Mean age of Group A (PEX group) was 59.06 ± 6.5 years and of Group B (control) was 57.04 ± 7.1 years (P = 0.51). Both groups were gender matched with male preponderance (P = 0.41). Mean average peripapillary RNFL thickness was 76.13 μm ± 13.65 in Group A (PEX group) and 82.61 ± 12.78 μm in Group B (control group) (P = 0.10). Mean superior RNFL thickness was 94.17 ± 16.25 in PEX group and 100.23 μm ± 13.21 in control group (P = 0.09). Mean inferior RNFL thickness was 89.67 μm ± 18.25 in PEX group and 102.45 μm ± 12.50 in control group (P = 0.03). Mean nasal RNFL thickness was 62.36 μm ± 15.36 in PEX group and 64.66 μm ± 13.71 (P = 0.56) in control group. Mean temporal RNFL thickness was 58.34 μm ± 14.32 in PEX group and 63.11 μm ± 15.25 (P = 0.08) in control group. Mean RNFL thickness was seen decreased in all PEX patients in all quadrants; however, statistically significant differences were detected only in inferior quadrant groups. Conclusion: RNFL thickness is decreased in PEX patients. SD-OCT is a very reliable investigative tool to measure RNFL thickness, which helps in detecting preperimetric glaucoma.