CT Derived Biomarkers for the Evaluation of Presacral Fat in Patients with Pelvic Floor Dysfunction

Background: Minimally invasive sacrocolpopexy is cited as the gold standard for treatment of apical pelvic organ prolapse. Inaccessibility of the sacral promontory has been associated with conversion to open sacrocolpopexy. It is not known if body mass index (BMI) or other biometrics are associated with sacral accessibility. The objective of this study was to investigate if imaging-derived biomarkers are correlated with pre-sacral fat thickness and volume as measured on CT imaging. Methods: This was a cross-section cohort study. CT-derived biomarkers including presacral fat thickness (PT), presacral fat volume (PV), waist circumference, hip circumference, and thigh circumference were measured radiologically. Clinicodemographic information including age, race, BMI, and pertinent medical history were extracted from the electronic medical record. Descriptive, univariate, and multivariate statistics were performed. Results: 143 women were included in the study. Mean BMI was 27.7 kg/m ² (SD 6.7). Mean PT was 16.2 mm (SD 6.5), and mean PV was 18.0 mL (SD 7.0). On univariate analysis, higher BMI, waist circumference, hip circumference, and thigh circumference were associated with larger PT. Age, BMI, hip circumference, waist circumference, lipid disorder, and thyroid disorder were positively correlated with larger PV. On multivariate analysis, higher BMI was associated with PT (p < 0.001), and larger waist circumference and presence of thyroid disorder were associated with larger PV (p = 0.034). Conclusion: Our study found that increasing BMI was associated with increasing PT. Increasing waist circumference and thyroid disorders were associated with increasing PV.