Preoperative Eyelid and Eyebrow Asymmetry: A Potential Pre-Operation Inform Consent Option: A Descriptive Cross-Sectional Study.

[BACKGROUND] We aimed to determine the prevalence of pre-existing asymmetry in our patients and investigate the impact of age and sex on upper facial asymmetry.

[METHODS] We collected images from 155 patients who were undergoing upper eyelid blepharoplasty and MRD1 (marginal reflex distance 1), TPS (tarsal plate show), and BFS (brow fat span) measurements were extracted by ImageJ software. The relationship between asymmetry and age and gender was assessed by comparing the mean differences of these metrics. A generalized linear model (GLM) was used to compare the outcomes of the study. P-value < 0.05 was considered significantly different in all tests.

[RESULTS] Pre-operative asymmetry was present in 112 (72%) patients. Among the cases, 61 (39%), 40 (26%), and 24 (15.5%) patients had more than 1mm of asymmetry in BFS, TPS, and MRD1, respectively. Males under 50 years old had the most asymmetry in the preorbital area. Comparing men under 50 years old with the other groups showed that the mean ± SD of absolute differences of TPS was significantly higher in this group (all P< 0.00), but pairwise comparison for MRD1 and BFS indicated no significant correlation between age, gender, and the mean asymmetry of these parameters (overall test P = 0.70 for MDR1 and P = 0.45 for BFS).

[CONCLUSION] Most patients have asymmetry before surgery without being aware of it. Awareness of this asymmetry and the relationship between facial asymmetry and age and gender is essential to prevent dissatisfaction due to the probable post-operative asymmetry and unrealistic expectations.