Self-contained, inflatable penile prosthesis: magnetic resonance appearance

A catalog of magnetic resonance imaging compatibility of penile prostheses

INTRODUCTION

Erectile dysfunction has been successfully treated with penile prosthesis implantation for over 50 years. Ferromagnetic implants or devices may create a potentially hazardous or painful situation during magnetic resonance imaging (MRI). A modern catalog of the MRI compatibility of penile prostheses is not available.

AIM

Evaluate the safety profile of implanted, penile prostheses during MRI.

MAIN OUTCOME MEASURE

Review available in vitro safety data and reported patient complications experienced during MRI with a penile prosthesis in place.

METHODS

A search of PubMed™ for articles documenting a penile prosthesis present during MRI was performed. Radiology texts and product information from manufacturers' producing a penile prosthesis were reviewed. Direct discussion with product manufacturers was also performed to obtain additional safety and compatibility information.

RESULTS

Nine clinical articles noted the presence of a penile prosthesis at the time of magnetic resonance imaging. No articles documented a complication from MRI of a man with a penile prosthesis. A single patient with an unnamed malleable prosthesis was noted to have twisting of the device during MRI which did not result in discomfort or malfunction of the device. In vitro studies support the safety of most prostheses during MRI.

CONCLUSION

The available data suggests there is little risk for most patients with a penile prosthesis who undergo MRI. Notable exceptions include Dacomed's Omniphase and Duraphase device and the MRI-conditional Spectra device manufactured by AMS. Current manufacturers of penile implants provide wallet cards and medical letters to support safety when undergoing an MRI. Prior prosthesis implantation should not preclude patients from having an MRI.

Radiological assessment of penile prosthesis: the role of magnetic resonance imaging

Penile implants offer a dependable way of restoring erections in virtually all motivated patients. The satisfaction rate among both patients and partners using these devices is high. Advances in technology have reduced the infection rate and increased the mechanical reliability of these products. However, too often, urologists do not present this option with the same authority as other treatments. The reason is fear of complications and lack of expertise in managing them. Although they are not very frequent, complications may be catastrophic. The most significant postoperative complication associated with the implant surgery is infection of the device, which is quite frequent, but some other important complications are distal and proximal perforation of the albuginea, SST deformity, "S-shaped" deformity of the penis, erosion of a component, and mechanical malfunction of the device. The best way to manage complications is to prevent them, but we do not have many diagnostic tools available. Diagnosis is based on clinical history and physical examination, but imaging techniques are also needed to explore the prosthesis "in situ" to plan the surgical approach if it is needed. In this article we review the different imaging techniques used for the diagnosis of complications of prosthetic surgery of the penis, including conventional radiology, use of sonography, the role of CT scan and the magnetic resonance imaging (MRI) of the penile prosthesis. We conclude that MRI is the most valuable method for the diagnosis of penile prosthesis complications. It is not an ionizing radiation imaging method and has the unique feature among imaging techniques of demonstrating penile anatomy in three orthogonal planes. It is superior to any other imaging method in the definition of soft tissue contrast.