Relaxation degree of cavernous smooth muscle: a novel parameter to predict postoperative success in penile revascularization.

Objective: To investigate the role of a new preoperative parameter, relaxation degree (RD), in the prediction of postoperative success after deep dorsal vein arterialization operations.
Patients and Methods: Chart reviews and electromyographic recordings were evaluated in 52 patients on whom deep dorsal vein arterialization was carried out for pure caverno-occlusive dysfunction. The efficiacy of the operation was assessed as improvement or failure according to the five-item version of international index of erectile function (IIEF). RD was defined as the percentage decrease in cavernous electrical activity (CEA) after intracavernous papaverine injection. Preoperative RD measurements were statistically compared between the improvement and the failure groups.
Results: The mean age of patients was 34.2 +/- 8.1 years (range 25-49) with a mean follow-up of 32 +/- 8 months. Improvement was observed in 39 (75%) and failure in 13 (25%) patients. The mean RD values were 60% and 32% for surgical improvement and failure groups respectively (P < 0.01). In patients with mild ED, the mean RD value was 70.3% whereas it was 28.7% in patients with severe ED. The RD value of greater than 40% predicts surgical success with a specifity of 75% and a sensitivity of 90%.
Conclusion: The RD value of cavernous muscle seems to decrease as the severity of ED increases. In addition, RD may predict the outcome of penile revascularization operations and it may be a useful preoperative indicator for surgical success.