Measurement of choroidal perfusion and thickness following systemic sildenafil (Viagra®)

. Purpose: To demonstrate anatomic and physiologic changes in the human choroid following systemic sildenafil citrate (Viagra®) using enhanced depth imaging spectral domain–optical coherence tomography (EDI‐OCT) and swept‐scan high‐frequency digital ultrasound. Methods: Seven healthy male subjects (mean age 32.7 years) were evaluated at baseline and 2 hr after ingesting 50 mg of sildenafil. Swept‐scan high‐frequency digital ultrasound and EDI‐OCT were utilized to measure choroidal perfusion and thickness, respectively. Results were read by masked observers. The Wilcoxon signed‐rank test and t‐test were used to analyse differences in choroidal flow and thickness at baseline and 2 hr after ingestion of sildenafil. Results: Two hours following sildenafil, increased choroidal perfusion was observed in 11 of 12 eyes measured by swept‐scan high‐frequency digital ultrasound. The mean increase was 3.46 (±2.00) times baseline with a range of 0.47–7.80 times baseline (p = 0.004). Increased choroidal thickness was observed in 12 of 12 eyes measured with EDI‐OCT. The average choroidal thickness increased by 11.6% temporal to the fovea, 9.3% nasal to the fovea and 10.7% underneath the fovea (p