(Poster 111) Association of Vaginal Area and Volume with Apical Native Tissue Repair Outcomes

Objectives: Widened genital hiatus, advanced prolapse stage, and higher POP-Q D and Bp points are associated with higher postoperative failure rates following native tissue repairs. Our group previously studied whether preoperative transvaginal diameter (TD) can predict postoperative success. There was no significant effect of preoperative TD on postoperative success, however there was a trend of increased odds of failure as TD increases. Using these findings, we hypothesized that a more accurate preoperative measurement may predict postoperative outcomes. Thus, we used area and volume calculations to model the vagina. The purpose of this study was to determine if preoperative vaginal area or vaginal volume predicts postoperative failure from native tissue repair. We hypothesize that increased preoperative vaginal area and volume have increased postoperative failure.

Methods: In this retrospective chart review from 2016 – 2021 we evaluated preoperative vaginal area and volume on postsurgical outcomes in women who have undergone vaginal colpopexy surgery at a tertiary hospital center.

Vaginal area was calculated using the following equations:
Radius a = preoperative transvaginal diameter / 2
Area = π r a^2

Vaginal volume was calculated using the following equations:
Radius b = preoperative genital hiatus / 2
Ovoid cylinder volume = radius a * radius b * π * preoperative transvaginal length

Overall failure was defined by having failure in at least one of the failure subcategories. Surgical failure was categorized into four different subjective and objective subcategories:
1. Need for repeat prolapse surgery, pessary placement, or subjective symptoms of a bulge (subjective)
2. Descent of vaginal apex more than one third of total vaginal length (objective)
3. Ba extending beyond the hymen (objective)
4. Bp extending beyond the hymen (objective)

Patients with a missing value needed to calculate preoperative vaginal area or ovoid cylinder volume or had missing values for all outcome variables were excluded from the analysis.

Continuous variables were summarized using means and standard deviations, and categorical variables were summarized using frequencies and percentages. Logistic regression was used to model the association between preoperative measurements and the outcome variables. Odds ratios, 95% confidence intervals, and p-values were reported.

Results: 123 patients were included in the area analysis. Overall, there was not a statistically significant effect of preoperative vaginal area on having failure in at least one of the defined surgical failure categories (p=0.155).

121 patients were included in the volume analysis. Overall, there was not a statistically significant effect of preoperative vaginal ovoid cylinder area on having failure in at least one of the defined surgical failure categories (p=0.135).

Conclusions: There was no statistically significant effect of preoperative vaginal area nor ovoid volume on postoperative failure defined by commonly used subjective and objective post-surgical outcome variables.