OBJECTIVETo investigate the ultrasonographic indexes in the evaluation of complete penile erection after oral administration of sildenafil citrate in men with normal erectile function.

METHODSThe subjects lay supine, with the penis raised upwards, its back clinging to the abdomen. The probe was placed at the base of the ventral side of the penis for longitudinal and transverse section scanning. Observations were made on the corpus cavernosum, deep artery and deep dorsal vein of the penis at the time of flaccidity and complete erection after oral administration of sildenafil citrate, respectively.

RESULTSThe examinations were acceptable to all the subjects both physically and psychologically, and all were completed successfully with no complications. Compared with the flaccid state of the penis, obvious changes were observed in the state of complete erection, including marked increases in the diameter of the corpus cavernosum ([18.57 +/- 2.50] mm, increased by [106.8 +/- 62.1]%), the inside diameter of the deep artery ([1.18 +/- 0.26] mm, increased by [54.9 +/- 29.0]%), the peak systolic velocity ([32.5 +/- 10.7] cm/s, increased by [209.3 +/- 112.9]%), and the systolic acceleration ([5.71 +/- 2.71] cm/s2, increased by [179.3 +/- 138.2]%).

CONCLUSIONOral administration of sildenafil citrate followed by ultrasonography is a new approach to the objective evaluation of penile erection, characterized by convenience, safety, non-invasiveness, non-complication, easy acceptability and easy clinical application.