Levator avulsion using a tomographic ultrasound and magnetic resonance–based model

Abstract

Delivery-related levator avulsion can cause pelvic floor dysfunction. We compared agreement between tomographic ultrasound and magnetic resonance-based models for the detection of levator defects. Sixty-nine Chinese women with pelvic organ prolapse were assessed prospectively by 3-dimensional ultrasound scans and magnetic resonance imaging. Levator-urethra gap (LUG), levator-symphysis gap (LSG), and puborectalis attachment width were measured offline with state-of-the-art software. Interobserver variability and agreement between the 2 methods were determined. Interobserver repeatability was moderate-to-excellent for all parameters that were measured with both methods and agreement between methods in diagnosing levator avulsion. LUG and LSG measurements were significantly higher in women with a levator avulsion. With a diagnosis of complete levator avulsion, receiver operating characteristics analysis suggested a cutoff of 23.65 mm for LUG and 28.7 mm for LSG. Levator avulsion can be diagnosed reliably by tomographic ultrasound scanning and magnetic resonance imaging evaluation, and linear measures, such as LSG and LUG, can be proxy measurements for avulsion.