Sequential penile ultrasound monitoring of patients treated with chronic intracavernous prostaglandin E1

Clinical outcome studies of prostaglandin E1 (PGE1) have shown a markedly decreased rate of palpable fibrosis and plaque formation. In this prospective study we investigate the potential of this agent to produce subclinical fibrotic changes. Real-time high-resolution ultrasound scanning of the corpora was performed using a 7.5 to 10 MHz linear array transducer in 80 men on initiation of treatment with self-administered PGE1 and at quarterly intervals during the course of following (3 to 28 months). The dorsal portion of the penile shaft was scanned in the transverse and sagittal planes from base to glans for a side by side comparison of the cavernosal tissue, evaluating local abnormalities of tissue echogenicity. Palpable lesions were not detected in any men on quarterly follow-up examination. Thirteen (16.5%) men developed new echogenic foci not present on pretreatment scanning at the following locations: proximal corpus cavernosum, subcutaneous tissues, and corpus spongiosum. These changes were observed both as single and multiple lesions ranging in size from 1 to 10 mm. The presence of these findings was independent of the etiology of impotence, dose frequency, and duration of intracavernous therapy. The significance of these subclinical changes is unknown but their low incidence should be recognized when considering long-term intracavernous therapy.