Diagnosis of levator avulsion injury: a comparison of three methods.

OBJECTIVE: Levator avulsion is common after vaginal delivery and is strongly associated with prolapse and prolapse recurrence. The aim of this study was to compare assessment by digital palpation and two ultrasound methods, one using rendered volumes and the other multislice imaging, for the diagnosis of levator avulsion.
METHODS: We retrospectively analyzed randomly identified datasets of 266 women seen at a tertiary urogynecology unit. Each patient had undergone an interview, vaginal examination and 3D/4D translabial ultrasound examination. Analysis of the retrieved ultrasound volumes was performed offline, with the operator blinded to all clinical data, using two techniques: assessment of rendered volumes and evaluation on multislice imaging. We tested agreement between the three methods and the association of each method's results with symptoms and signs of pelvic organ prolapse.
RESULTS: Agreement between the findings on palpation and the two ultrasound methods with regard to diagnosis of levator avulsion ranged from 80% to 87% (Cohen's kappa, 0.35-0.56). The findings for all methods were significantly associated with symptoms, signs and ultrasound findings of pelvic organ prolapse (P=0.007 to < 0.001), with no single method appearing superior to the others.
CONCLUSIONS: Depending on the availability of local expertise and equipment, any of the three methods tested in this study may be used to document avulsion of the puborectalis muscle.