Purpose: To analyze routine preoperative prostate MRI to predict erectile function (EF) before and after radical prostatectomy (RP).
Methods: Patients who underwent RP with an existing preoperative MRI including dynamic contrast-enhanced images and completed International Index of Erectile Function (IIEF-5) questionnaires at baseline and 12 months postoperative. They were divided into four erectile dysfunction (ED) groups according to preoperative IIEF-5 score. The perfusion quality was measured in the peripheral zone of the prostate by the ratio of signal increase 120 s after wash-in of contrast agent (Ratio120) in preoperative MRI and compared between the ED groups.
Results: Ratio120 showed differences among the preoperative ED groups (p = .020) in 97 patients. According to IIEF-5 at 12 months postoperative, 43 patients were dichotomized into "no to mild" (≥17 points) and "moderate to severe" (≤16) ED groups. Ratio120 revealed differences among the postoperative ED groups (128.84% vs. 101.95%; p = .029) and stayed an independent predictor for ED in the multivariable regression analysis (adjusted for age, nerve-sparing and preoperative IIEF-5). ROC curves demonstrated an additional diagnostic benefit.
Conclusions: Preoperative MRI of the prostate may be used for the prediction of EF and postsurgical recovery after RP. This may serve as important tool in preoperative patient counseling and management of expectations.
Keywords: Erectile dysfunction; MRI; contrast-agent; diagnostic imaging; prostatectomy.