Buckling of cylinders may cause prolonged penile pain after prosthesis implantation: a case control study using magnetic resonance imaging of the penis.

PURPOSE

We identify risk factors associated with chronic postoperative penile pain after inflatable prosthesis insertion.

MATERIALS AND METHODS

We performed a case control study to determine the incidence of prolonged penile pain in 65 men who underwent prosthesis insertion. The association of various potential risk factors, including diabetes mellitus, incision site, prosthesis type, patient age and history of pelvic surgery, was assessed. In addition, the penis was examined for physical findings, and penile magnetic resonance imaging (MRI) was done as an in situ evaluation of the anatomical position and functional status of the inflatable prosthesis.

RESULTS

A total of 14 patients (21.5%) with prolonged pain were compared to the remaining 51 with no pain. All parameters evaluated were similar in both groups except for MRI findings. Of the 14 patients with pain 12 (85.7%) had buckling of the cylinders in the flaccid state compared to only 1 of the 51 controls (1.9%). Statistical analysis showed a highly significant association between buckling and penile pain (odds ratio 300, p <0.0001). Surgical correction of buckling resolved pain in 5 patients.

CONCLUSIONS

Prolonged postoperative penile pain after prosthesis insertion is strongly associated with cylinder buckling. This buckling may be the consequence of an excessively long cylinder or an appropriate size cylinder that fails to reach the crural end. The method of accurately diagnosing these alterations is MRI of the penis.