Background: The eyebrows and eyebrow fat pads, key structures in upper facial aesthetics, are particularly vulnerable to age-related changes.
Objectives: In this study, the authors compare the impact of aging on the eyebrows and eyebrow fat pad volume in men and women through three-dimensional (3D) volumetric analysis.
Methods: Electronic medical records of patients seen at the Jules Stein Eye Institute in the Division of Orbital and Ophthalmic Plastic Surgery between 2005 and 2010 were reviewed. Patients were included if they had undergone investigative imaging of the orbit for unilateral pathology. Computed tomography (CT) scans of patients with Graves disease diagnosis, extensive orbital trauma, and/or previous eyebrow surgery were excluded. A total of 52 CT scans (24 men and 28 women) were retained for analysis. A 3D reconstruction software was used to analyze the scans and calculate volumes of the retroorbicularis oculi fat (ROOF), galeal fat (ROOF and subcutaneous fat), and soft tissue muscles.
Results: Galeal and brow fat volumes showed a significant positive trend toward enlargement in women (P values of .01 and .05, respectively). Although men showed a tendency toward fat enlargement with age, this was not statistically significant. Soft tissue-muscle volume decreased significantly in aging women (9.32 mm(3)/y) (P = .02). Data indicated that soft tissue volume in men tended to increase with age (3.92 mm(3)/y) but not significantly (P = .36). Neither total volume nor brow thickness appeared to change significantly in women (P = .56, P = .73). In men, total volume and brow thickness showed weak evidence of increasing with age (P = .12, P = .22). Linear regressions of Hertel measurements with and without sex interaction showed no statistically significant trend between the amount of proptosis and the galeal or brow fat.
Conclusions: Although overall eyebrow volume does not change with age, the relative contribution of fat and soft tissue to the total volume does seem to change. This pattern also differs between males and females. As women age, the fat volume increases and the soft tissue volume decreases. In men, the shift from soft tissue volume to fat volume is less pronounced. Although many clinicians have been drawn to the concept of fat volume deflation as a key element of facial aging, this study does not support this perspective in the eyebrow fat pad. An increasingly refined understanding of the dynamics of facial aging is mandatory for clinical diagnosis and will likely provide the framework from which to develop more innovative treatment options.