Proposing ultrasonic elastography as new evaluation method for erectile function

Abstract

ABSTRACT Introduction For diagnosing vasculogenic erectile dysfunction (ED), the prostaglandin E1 intracavernous injection test (PGE1 test) is an established method. However, its evaluation is often influenced by the subjectivity of the evaluator. Objective We objectively evaluated the changes in the corpus cavernosum before and after injection using percutaneous ultrasonic elastography in patients undergoing the PGE1 test. Methods We measured and evaluated the shear wave velocity in the corpus cavernosum by ultrasonic elastography (Canon Medical Systems Co., Ltd. Aplio i800) before and after injection, by a single doctor, in 16 patients who underwent the PGE1 test at our hospital, between April 2020 and March 2021. Results The response score of PGE1 tests were "1" in 2 cases, "2" in 2 cases, "3" in 12 cases, while "0" and "4" were not observed. The average transmission velocity before injection was 2.21m/s, and the average transmission velocity at the time of maximum erection after injection was 1.57m/s. In 14 of 16 cases (87.5%), the transmission velocity decreased during erection. The rate of change in transmission velocity due to injection was minus 26.7% overall, and was significantly different between the poor erection group (response 1 and 2: minus 16.1%) and the good erection group (response 3: minus 30.2%). Conclusions To our knowledge, this is the first report of an attempt to evaluate erectile phenomenon by ultrasonic elastography. The rate of change in the shear wave transmission velocity due to PGE1 test in the penile corpus cavernosum was associated with the degree of erection. It was suggested that the rate of change in shear wave transmission velocity in the penile corpus cavernosum could be used as an objective index of erectile phenomenon. Ultrasonic elastography is a non-invasive test method; therefore, it will be useful for patients if this method becomes established for diagnosing ED, determining the therapeutic effect, and predicting the prognosis. Disclosure Work supported by industry: no.