Transurethral/sonomorphologic evaluation of male external sphincter of urethra

Abstract

Sonoenorphotogic criteria of male urethral external sphincter under normal and pathologic conditions were evaluated by direct visualization with endoluminal US and correlated with normal anatomy. Between October 1992 and August 1993 18 patients were examined prospectively. We used a 12.5 MHz interventional US machine eduipped with a Sonicat 9-French catheter system. In all cases the anatomic structure of the external male urethral sphincter was visualized and demonstrated not in the expected circular configuration, but rather in an “omega sign” of the muscle and fibers, functioning with retraction of the ventral and lateral parts of the muscle, surrounding the urethra. Disorders of muscular function were revealed in 8 cases, and 6 cases demonstrated scarring and thinning of the muscle. Endoluminal-US offers the possibility of direct visualization not only of the male external sphincter, but also of the contracting mechanism in cross-sectional view. An exact description of sonoanatorny and the pathoenorphologic correlation is more accurate. The method therefore has the benefit of better access to further therapeutic considerations.