Does levator ani injury affect cystocele type?

Abstract

To determine the prevalence of levator ani injury in patients with different types of cystocele, as defined by translabial ultrasound, in order to shed light on potential pathophysiological mechanisms. The datasets of 222 women who had undergone a physical examination, urodynamic testing and four-dimensional (4D) pelvic floor ultrasound were evaluated offline for prolapse, levator ani hiatal dimensions and levator ani trauma using tomographic ultrasound imaging (TUI), blinded against all clinical and urodynamic data. Cystoceles reaching below the symphysis pubis on ultrasound examination were classified based on bladder neck position, retrovesical angle (RVA) and urethral rotation as Green II (cystourethrocele) or Green III (cystocele with intact RVA). Of 102 women who had a cystocele reaching below the symphysis pubis, 63 were classified as a Green type II cystocele and 39 as a Green type III cystocele. Women with Green type III cystoceles were older (59.4 vs. 48.7 years, P < 0.001), and had more severe prolapse (71 vs. 43%, P = 0.004) and objective voiding dysfunction (39 vs. 18%, P = 0.018). Women with Green III cystoceles also had larger hiatal dimensions and were more often diagnosed with an avulsion of the levator ani muscle (69 vs. 35%, P = 0.001). A cystocele with an intact RVA is more likely to be associated with avulsion injury of the levator ani muscle and thus more likely to be caused by birth-related trauma. This contradicts the commonly held belief that such cystoceles are caused by central rather than by lateral fascial defects.