MRI of Penile Prostheses: The Challenge of Diagnosing Postsurgical Complications

Penile implants are surgically inserted devices used for the treatment of erectile disfunction. Improvements in surgical techniques and in the manufacturing of these implants have reduced the risk of intra- and postoperative complications and increased the popularity and use of this therapeutic option. Routine imaging is not recommended before penile prosthesis surgery. Malleable penile prostheses use noninflatable shafts inserted into each corpus cavernosum, which appear hypointense on T1- and T2-weighted MR images. Inflatable penile prostheses (IPPs) may consist of two or three parts and are composed of two cylinders inserted into the corpora cavernosa that are filled with a saline solution to produce rigidity. These appear homogeneously T2 hyperintense and the silicone-based covering of the cylinders appears T2 hypointense, thereby clearly delineating the cylinders. In the case of three-piece IPPs, a reservoir containing the fluid may be placed in the pelvis. The most frequent complications are related to infection and mechanical failure, the latter being more common in IPPs because more components are involved. Less common complications include malpositioning. Detection and management of postoperative complications are challenging, and MRI plays a crucial role as it permits evaluation of the positioning and configuration of the prosthesis components, as well as assists in functional evaluation of IPPs when images are obtained of both the flaccid and inflated states. ^©RSNA, 2021.