Visceral fat is correlated with prolonged operative time in laparoendoscopic single-site adrenalectomy and laparoscopic adrenalectomy

Objective To investigate the effect of visceral fat on operative time and discuss whether the measurement of adipose accumulation could be used as a sensitive predictor of technical difficulty in performing laparoendoscopic single-site adrenalectomy (LESS-A) and laparoscopic adrenalectomy (LA). Methods We reviewed the medical records of 106 patients undergoing LA or LESS-A at our institution. Total fat area (TFA) and visceral fat area (VFA) were measured at the level of the L4 vertebra by computed tomography. To categorize the type of obesity, the VFA/TFA ratio was calculated. Multiple logistic regression analyses were performed to identify independent predictors of prolonged operative time. Results The VFA/TFA ratio does not always coincide with body mass index (BMI, r = 0.415), and a higher correlation coefficient was observed between operative time and the VFA/TFA ratio (r = 0.359) than with that of BMI (r = 0.189). Multivariate analysis revealed that pheochromocytoma, tumor size ≥5 cm, and the VFA/TFA ratio ≥0.35, defined as the visceral type of adipose accumulation, were independent predictive factors for prolonged operative time in LA and LESS-A. We were able to stratify patients into short, intermediate, and long operative times using these preoperative variables. Conclusion This study revealed that the visceral type of adipose accumulation increases operative complexity in LA and LESS-A as measured by operative time. The VFA/TFA ratio might be a more sensitive indicator of technical difficulty than that of BMI.