Quantitative evaluation of the function of levator ani muscle after vaginal delivery and pelvic prolapse by MRI

Abstract

Objective To investigate the value of MRI in the quantitative evaluation of the function of levator ani muscle after vaginal delivery and pelvic prolapse(POP). Methods Sixty-two cases of vaginal delivery primipara were selected as observation group, 40 cases of non pregnancy healthy women in the same period were selected as control group. GE signa HD 1.5 T superconduct MR scanner was used to perform static and dynamic pelvic magnetic resonance imaging (MRI), the imaging manifestations of levator ani muscle in two groups were observed, the anal muscle injury of two groups were determined by the professional doctors in the same group according to the puborectalis musculus image and the iliococcygeus musculus image. According to the clinical history, physical examination and ultrasound or MRI results, the observation group was divided into the POP group (28 cases) and normal pregnancy group (34 cases), and by measuring maternal H line from the resting period to the maximum force, anus muscle fissure area(LHS), levator ani plate angle(LPA), bilateral iliococcygeus angle(ICA) and other indexes, quantitative comparison of MRI measurement parameters of levator ani muscle in the two subgroups was completed. Results The levator ani muscle injury of observation group accounted for 27.42%(17/62), and the control group had no levator ani muscle injury, the difference was significant (P 0.05); Under maximal abdominal pressure, H line in the resting state, LPA, LHS, bilateral ICA of the POP group were higher than those of the normal pregnancy group and the resting state of the POP group, the differences were significant (P<0.05). Conclusions After vaginal delivery, it is easy to cause the damage to the levator ani muscle and increase the risk of POP. The static and dynamic MRI quantitative test can evaluate the function of the muscle function. Key words: Magnetic resonance imaging; Vaginal delivery; Pelvic prolapse; Function of levator ani muscle; Evaluation value