Intracavernosal drug-induced erection therapy versus external vacuum devices in the treatment of erectile dysfunction

To determine if there is a significant difference between intracavernosal self-injection and external vacuum devices when compared directly for satisfaction, effectiveness and side-effects.

Fifty men were randomised into two groups and received either instruction on the use of the Osbon ErecAid system or self-injection therapy. After 15 uses, each group completed a questionnaire detailing efficacy, satisfaction and side-effects, and then changed to the other modality after appropriate instruction. A questionnaire was completed by study participants and their sexual partners after using both methods. Patients were followed for 18-24 months using telephone interviews.

Forty-four patients (mean age 62.3 years, range 38-84) completed the study. Patients and their partners reported a superior quality of erections with the injection method but the difference did not reach statistical significance. The ability to attain orgasm and the overall satisfaction of the patient and partner with the sexual experience was significantly better when using injections. Side-effects were similar between the modalities. Subgroups analysed for age, duration and aetiology of impotence showed that younger patients (< 60 years), those with a shorter duration of impotence (< 12 months) and those impotent secondary to radical prostatectomy strongly favoured injection therapy (P < 0.05). Overall, of the 44 couples, the final preferences of the patients were 25 (57%), 12 (27%), six (14%) and one (2%) for the injection, vacuum device, both or neither, respectively, and of the partners were 22 (50%), 12 (27%), six (14%) and four (9%), respectively. At 18-24 months, 80% of patients were still using either the vacuum device, injections, or both.

Both the vacuum device and injections are effective treatment modalities for impotence and are associated with good long-term success. Overall, there was a trend favouring injection therapy over the vacuum device which was most significant in younger patients, those with a shorter duration of impotence, and those impotent secondary to radical prostatectomy.