Correlation of patient age with CT-measured aorta-sacral promontory distance

Pelvic floor disorders are becoming more prevalent in the elderly population. Since more patients are seeking definitive management for their prolapse, the number of elderly patients undergoing sacral colpopexies will likely increase. During sacral colpopexies, the surgeon must carefully dissect in the presacral space and avoid vital structures. In elderly patients the aorta potentially elongates and the vertebral body height decreases. Consequently, there is a potential for anatomical change of distance from the bifurcation of the aorta to the sacral promontory. This study aimed to correlate the aorta-sacral promontory distance with age. From 1 January 2013 to 31 January 2014 computed tomography (CT) images of 241 patients were reviewed in this retrospective study. Radiologists measured the aorta-sacral promontory distance on sagittal acquisition. The corresponding demographic information of age, body mass index, and comorbidities was evaluated using univariate analysis and univariate linear regression. The mean age was 56.6 years, and BMI was 27.6. The mean aorta-sacral promontory measurement based on the CT scan was 63.11 mm. Univariate analysis using a t test and ANOVA demonstrated an inverse correlation with age (p < 0.0001) and hypertension (p = 0.0034) and a positive correlation with BMI categories (p < 0.0017) Under univariate linear regression, the weight of the patient in kilograms demonstrated positive correlation (p = 0.0413). Based on CT measurements, the aorta-sacral promontory distance is decreased in elderly and hypertensive patients. Heavier patients have an increased aorta-sacral promontory distance. These potential anatomical variants should be considered before operating in the presacral space.