Association of body mass index with orbital fat volume in lower eyelid blepharoplasty

To investigate the relationship between body mass index (BMI) and the volume of orbital fat excised during lower eyelid blepharoplasty. This retrospective cross-sectional study included 58 patients who underwent bilateral transconjunctival lower eyelid blepharoplasty between January and December 2024. Total orbital fat volume was measured intraoperatively using a graduated cylinder. BMI was calculated from preoperative height and weight and classified according to World Health Organization criteria. Statistical analyses included Pearson correlation, one-way ANOVA with Tukey’s post-hoc test, and univariate and multivariable linear regression. The mean age of the patients was 49.2 ± 11.6 years, and the mean BMI was 24.5 ± 3.8 kg/m². The mean total orbital fat volume excised was 2.08 ± 0.94 cc. Fat volume differed significantly across BMI categories (p < 0.001), with obese and overweight patients having greater excised fat than normal-weight individuals. Pearson correlation demonstrated a strong positive association between BMI and fat volume (r = 0.592, p < 0.001). In regression analysis, BMI was the only significant predictor of orbital fat volume, explaining 35.1% of the variance (R²=0.351). BMI is strongly associated with orbital fat volume excised during lower eyelid blepharoplasty. These findings suggest that systemic adiposity extends to the periorbital region and highlight the relevance of considering BMI in preoperative planning to optimize surgical outcomes.