Prosthetic device for ED shows early promise

March 1, 2007

Las Vegas-In a recent trial, men with erectile dysfunction and their partners reported that they were somewhat satisfied with a new wrap-around prosthetic device used to stiffen the men's penises.

"It's not off-the-charts successful, but 90% of patients indicate satisfaction," said Kenneth C. Hsiao, MD, assistant professor of urology at Indiana University Medical Group, Indianapolis, who presented results of the phase I trial at the Sexual Medicine Society of North America fall meeting here. "I think it will help restore the intimacy in people's lives, and that's important."

The device, called an erectile prosthetic support or EPS (Indiana University Advanced Research & Technology Institute, Indianapolis), consists of a thin band that wraps around the shaft of a flaccid penis and a backing disc that fits around the base of the penis. The band provides lengthwise rigidity, but can expand or contract radially with changes in penile turgor pressure, according to Dr. Hsiao. The EPS can sustain more than 10 pounds of force, roughly seven times the amount necessary for penetration. The band doesn't constrict blood vessels as a vacuum system does; instead, it provides "gentle but rigid support" through its own structure, according to the researchers. The band is thin, with contours that are similar to those of a condom.

The device leaves the primary sexual receptors in the glans penis exposed, and men in the study were able to achieve orgasm, but how often men can ejaculate using the EPS will be the subject of future investigation.

Device successful in testing

To test the device's efficacy, Dr. Hsiao and his colleagues used newspaper ads to recruit 36 couples in stable relationships. The men were shown how to use the EPS and were instructed to go home and try it one to five times with their partners.

After each use, the couples were asked to fill out 11 questions from the Erectile Dysfunction Inventory of Treatment Satisfaction questionnaire and mail the survey to the investigators. On the questionnaires, the patients rated their satisfaction on a scale of 1 to 5, in which 1 is "very satisfied" and 5, "very dissatisfied." Twenty couples completed the study.

Overall, the men gave the device a mean score of 2.40 (range, 2.23-2.66, 95% CI), and 90% expressed some satisfaction. The partners gave the prosthesis a mean score of 2.88 (range, 2.55-3.10, 95% CI), and 70% had some satisfaction with it. The correlation coefficient ® for the questionnaires of patients and partners was .95.

Written comments were mostly positive. "Resurrected our sex life, many thanks," one man wrote. "My husband and I owe you very much for what you have done for us," commented a wife.

Such comments should be taken with a grain of salt, cautioned Ricardo Munarriz, MD, associate professor of urology, Boston University Medical Center.

"If you have severe erectile dysfunction and a treatment provides an erection, you're going to be satisfied," Dr. Munarriz said. "However, this is a pilot study and the question is: What is the safety and efficacy of this device when compared to PDE-5 inhibitors, intracavernosal injections, vacuums, and penile implants?

"All treatments for erectile dysfunction are welcome, as long as they are safe and effective," he added.

The device is the invention of study co-author Alfred Strickholm, PhD, a physiologist and professor emeritus at Indiana University. The study was funded by a grant from the National Institutes of Health.