58: Mind the gap – Changes in levator dimensions following sacrocolpopexy

Abstract

Prior studies demonstrated that genital hiatus (GH) decreases following surgical correction of the vaginal apex. We hypothesized that the underlying levator hiatus (LH) and levator area (LA) would decrease following apical suspension in women with preoperative prolapse (POP) beyond the hymen. Our objective was to compare LH and LA on transvaginal 3D ultrasound (US) and the GH, as measured by POP-Q exam, before surgery and at 14 weeks following sacrocolpopexy without posterior repair or perineorrhaphy. This was a prospective cohort study of women undergoing minimally-invasive sacrocolpopexy +/- hysterectomy without posterior repair or perineorrhaphy for stage II or greater POP beyond the hymen. At baseline and 14-weeks after surgery, patients underwent POPQ exam and US performed at rest. US was performed using multi-frequency 360° rotational probe with a 3D automatic acquisition system (Type 20R3 BK Medical, Herlev, Denmark). Data from each study were de-identified and analyzed by two urogynecologists, blinded to image sequence. The LH was measured from the junction of the superior pubic rami to the posterior margin of the external anal sphincter in the axial plane with urethra, puborectalis muscle, and anal canal visible simultaneously. Based on prior studies of POPQ GH change, we calculated that 32 women were needed to find a 1cm change in GH with 80% power and an alpha of 0.05. Measurements and scores were compared in SPSS Version 25 using paired t-tests for continuous variables. Correlations of non-parametric data are reported as Spearman’s rho. 43 patients were enrolled in the study; 35 completed all preoperative and postoperative ultrasounds and are included in the analysis. Patients had a mean age ± SD of 55 ± 11. Most were white (89%), parous (94%), postmenopausal (66%), sexually active (63%) and had stage III POP (86%). The majority (89%) had concomitant total hysterectomy, and 60% had a midurethral sling. At baseline, mean PFDI scores were 98±50 and mean POPDI subscale scores were 42±22. Median (IQR) POP stage decreased after surgery from 3 (3-3) to 0 (0-1) (p<0.001) and mean PFDI scores decreased to 55±42 (p=0.002). At baseline, mean GH was 3.5 ± 0.7cm and mean perineal body (PB) was 2.4 ± 0.6. While the GH decreased by 0.5cm following surgery, PB was unchanged (Table 1). LH increased by 1mm at 14 weeks postoperatively while LA remained unchanged (Table 1). At 14 weeks, the change in LH was not correlated with the change in GH (ρ= -0.2, p=0.2) or POP stage (ρ= -0.2, p=0.9) as measured on POPQ exam. Repositioning the apex with sacrocolpopexy significantly reduces GH size on clinical exam; however, restoration of the apex does not impact the size of the underlying levator hiatus or levator area suggesting that size of the levator gap does not impact sacrocolpopexy outcomes.