Multilevel musculo-fascial defect magnetic resonance study of female pelvic floor: retrospective case control study in women with pelvic floor dysfunction after the first vaginal delivery.

Introduction: Magnetic resonance imaging (MRI) provides a detailed display of the pelvic floor structures responsible for normal pelvic floor anatomy. The aim of the study is to assess the appearance of musculo-fascial defects in women with pelvic floor dysfunction following first vaginal delivery.

Material And Methods: Analysis of axial T3 (Tesla 3) MRI scans from a case control study of symptomatic (n = 149) and asymptomatic (n = 60) women after first vaginal delivery. Presence and severity of pelvic organ support and attachment system defects in three axial pelvic planes were assessed.

Results: In the symptomatic group, major muscular defects were found in 67.1% (for pubovisceral muscle complex) and 87.9% (for iliococcygeal muscle). Only 6.7% of major pubovisceral and 35.0% of major iliococcygeal defects were identified in the controls (p = 0.000). Prolapse patients had an odds ratio (OR) of 22.1 (95% CI 8.94-54.67) to have major pubovisceral muscle complex defect and OR of 4.9 (95% CI 1.51-15.71) to have major iliococcygeal muscle defect. Fascial defects were found in 60.4% and 83.2% the symptomatic group, respectively. Those with prolapse had an OR of 29.1 (95% CI 9.77-86.31) to have facial defect at the level of pubovisceral muscle complex and an OR of 16.9 (95% CI 7.62-37.69) to have fascial defect at the level of iliococcygeal muscle. Uterosacral ligaments detachment was associated with prolapse with an OR of 10.1 (95% CI 4.01-25.29). For the model based on combination on all MRI markers, the area under the receiver operating characteristic curve is 0.921.

Conclusions: This study provides comprehensive data about first vaginal delivery-induced changes in the levator ani muscle and endopelvic fascial attachment system. These changes are seen also in asymptomatic controls, but they are significantly less expressed.