Retinal nerve fiber layer thickness in the acute phase of sildenafil treatment.

OBJECTIVE To evaluate the early effect of sildenafil on the retinal nerve fiber layer (RNFL) thickness. PATIENTS AND METHODS Sixty eyes of 60 patients were enrolled in the study. The patients underwent RNFL analysis by scanning laser polarimetry (Nerve Fiber Analyzer, GDx VCC:5.3.3; Laser Diagnostic Technologies, San Diego, CA, USA) before and after a single 100 mg dose of sildenafil. Sixty eyes of 60 volunteers of similar age and sex distribution were taken as the control group. The RNFL thickness parameters evaluated included temporal, superior, nasal, inferior, temporal (TSNIT) average, superior average (SA), inferior average (IA), TSNIT standard deviation (SD), and nerve fiber index (NFI). RESULTS The mean age of the patients was 53,52 ± 9,26 years. The mean pre- and post-treatment TSNIT, SA, IA, TSNIT SD, and NFI of the patients were 57.46 ± 4.94 µ versus 56.90 ± 4.59 microns (µ), 68.93 ± 6,12 µ versus 67,79 ± 5,49 µ, 66,71 ± 7.10 µ versus 66.31 ± 6.82 µ, 24 ± 3.86 µ versus 23.40 ± 4.05 µ, and 16.50 ± 6.08 µ versus 14.92 ± 6.76 µ, respectively. There were no statistically significant differences between pre- and post-treatment RNFL thicknesses (p = 0.527, p = 0.281, p = 0.754, p = 0.416, p = 0.185, respectively). CONCLUSIONS A single 100 mg dose of sildenafil seems to have no unfavorable effect on RNFL thickness in the acute phase of treatment.