A smartphone application designed to help measure penile curvature and narrowing in men with Peyronie’s disease may be a reliable, noninvasive way to assess this condition.
Peyronie’s disease, thought to be a wound-healing disorder, is characterized by hardened areas of scar tissue called plaques. The plaques decrease the flexibility of the penis, causing it to bend when erect. The penis may also narrow and take on an hourglass shape.
Peyronie’s disease can be painful and interfere with intercourse. Many men with the condition feel depressed, anxious, and distressed.
The condition can be difficult to assess, however, as there is no standardized measurement method. To evaluate curvature and narrowing, the penis must be erect. But in a physician’s office, this erection is usually medically induced and may be different from the kind of erection a man has with sexual stimulation. Men may find the procedure invasive and there is a risk of priapism.
American researchers at the University of Washington developed a smartphone application (the University of Washington Peyronie’s Examination Network or UWPEN) that men and their physicians can use to assess the degrees of curvature and narrowing. The application also allows men to measure these aspects in the privacy of his own home.
The smartphone application allows men (or their partners or physicians) to take photographs of the erect penis. Using a touchscreen, men can indicate the angle of the curvature and the areas that are narrowed. For privacy, the pictures are processed so that images cannot be identified.
This study analyzed the application’s performance in terms of intertest, interobserver, and intraobserver reliability.
Three blinded observers participated in the study. They were a board-certified urologist with training in Peyronie’s disease, a urology resident, and a nonurologist.
Each observer was asked to measure the angle of fifteen malleable cylinders that were curved to varying degrees as a penis might. The observers used a protractor, goniometer, and UWPEN. Each cylinder was measured three times with each instrument.
A set of six clay models was used to represent typical penile girth and narrowing found in men with Peyronie’s disease. The same observers measured each model with a ruler and with UWPEN.
The researchers found that the measurements taken with UWPEN, for both curvature and narrowing, were comparable to those taken with the protractor, goniometer, and ruler. Among the three observers, measurements were reliable. Also, each observer could reproduce accurate UWPEN measurements.
Some limitations were acknowledged. For example, UWPEN could not take the place of a physical exam, which would be necessary to evaluate plaques. Also, patients may be wary of using a smartphone application in such a personal way and have concerns about privacy, even if it was assured.
However, they authors concluded, “The findings from this study suggest that UWPEN may provide an accurate, reliable, and widely accessible method to characterize and track [Peyronie’s disease] deformity over time, which may overcome may of the drawbacks of the current methods to assess [Peyronie’s disease].”
The study was published online in April in The Journal of Sexual Medicine.
The Journal of Sexual Medicine
Hsi, Ryan S. MD, et al.
“Validity and Reliability of a Smartphone Application for the Assessment of Penile Deformity in Peyronie's Disease”
(Full-text. April 3, 2013)