Objectives: To assess the efficacy of intraurethral prostaglandin E1 (alprostadil, MUSE) in treating erectile dysfunction in patients with spinal cord injury (SCI).
Methods: Intraurethral alprostadil was tested in 15 patients with SCI to evaluate its effectiveness in treating SCI-associated erectile dysfunction. All patients were at least 1 year after injury, and all had previously used intracavernosal injections successfully (Schramek's grade 5 erection). The intraurethral drug was administered in the office, in the presence of a physician, with monitoring of blood pressure. If effective, the patient was then able to use MUSE at home. The first 3 patients underwent gradual dose escalation starting with 125 microg, without the use of a constriction ring. Because of hypotension, the remaining 12 patients all used a penile constriction ring prior to intraurethral drug administration using 1000 microg. The quality of the erection was compared with that achieved with intracavernosal injections using Schramek's grading.
Results: The dose escalation (titration) in the first 3 patients demonstrated that the 1000-microg dose was the most effective in creating an erectile response. Transient hypotension was noted in these first 3 patients in whom the constricting band was not used. The highest dose of MUSE (1000 microg) was, therefore, used in the remaining 12 patients, with the constriction band. The quality of the erection varied and appeared to be less rigid in all patients (12 patients with grade 1 to 3; 3 patients with grade 4) than that noted with intracavernosal injection therapy (1 5 patients with grade 5). There was no incidence of priapism. The 3 patients with grade 4 erections tried the MUSE at home. All 3 patients were dissatisfied with the quality of the erection and did not continue to use the MUSE at home and returned to intracavernosal injection therapy.
Conclusions: MUSE appears to be somewhat effective in creating erections; however, these were less rigid erections than those obtained with intracavernosal therapy and provided less overall satisfaction. It should always be used in the patient with SCI after placement of a constriction ring to prevent hypotension. Its ultimate use depends on the patient's level of satisfaction with the quality of the erection compared with intracavernosal injections.