Choroidal Thickness Values Following the Consumption of Sildenafil and Tadalafil: Comparison of the OCT Records

Objective: The aim of this study is to demonstrate the anatomic and physiologic changes in the choroid following systemic sildenafil and tadalafil. Methods: This cross-sectional randomized study enlisted 20 young and healthy men, who were randomly and equally classified in two groups; group A received 50 mg of Sildenafil, whereas group B received 10 mg of Tadalafil. All participants underwent a measurement of choroidal thickness, based on enhanced depth imaging optical coherence tomography (EDI-OCT). The measurement was repeated two hours after the consumption of each PDE-5 inhibitor. Results: The mean age of participants was 34.2 ± 3.0 and 34.6 ± 3.2 years in group A and B, respectively. The mean values of choroidal thickness (CT) in Group A at baseline were 306.6 ± 11.1 μm, 229.9 ± 12.7 μm and 311.3 ± 21.8 μm in temporal, nasal and inferior quadrants, respectively. The mean increase in choroidal thickness in Group A two hours after receiving sildenafil was 29.9 μm, 23.8 μm and 34.2 μm in temporal (CI [-35.18,-24.62], p<0.001), nasal (CI [-27.20,-20.40], p<0.001) and inferior (p=0.005) quadrants, respectively. On the other hand, the mean values of choroidal thickness in Group B at baseline were 307.2 ± 10.6 μm, 227.4 ± 8.9 μm and 315.8 ± 9.1 μm in temporal, nasal and inferior quadrants, respectively. Significant raise was also noted in Group B two hours after tadalafil intake in temporal (13.2 μm, CI [-17.77,-8.63], p<0.001), nasal (12.7 μm, CI [-14.75,-10.65], p<0.001) and inferior (15.6 μm, CI [-17.36,-13.84], p<0.001) quadrants, respectively. The increment in choroidal thickness observed after the intake of PDE-5 inhibitors was greater in group A and this difference exhibited statistical significance (independent samples t-test, CT temporal: t(18)=5.338, p<0.001, 95%CI [9.95, 22.85], Levene's test: p=0.791, CT nasal: t(18)=6.332, p<0.001, 95%CI [7.48, 14.92], Levene's test: p=0.088, Mann-Whitney test, CT inferior: p<0.001). Conclusion: Both sildenafil and tadalafil resulted in the increment of choroidal thickness, but tadalafil caused a lower increase. This alteration could secondary affect retinal function or be a useful adjunct whenever increase choroidal blood flow is demanded.