The color difference in orbital fat

Objective: To identify and quantify carotenoids found in white and yellow orbital fat. Methods: Specimens of nasal (white) and preaponeurotic (yellow) orbital fat were obtained from patients during upper eyelid blepharoplasty. Carotenoids and retinoids were extracted and subjected to spectral and high-performance liquid chromatography analyses. Results: The chromophore content of extracts from unsaponified fat, as measured by absorbance at 425 nm per gram of fat, was 2- to 4-fold higher in preaponeurotic fat than in nasal fat. High-performance liquid chromatography analysis from enzymatically digested fat revealed large amounts of lutein, β-carotene, and retinol and small amounts of other unidentified carotenoids. The amount of β-carotene and lutein in preaponeurotic fat was approximately 4-fold higher than in nasal fat. Conclusions: The higher carotenoid content of preaponeurotic fat might cause it to be more yellow than other orbital fat, and lutein and β-carotene might be selectively absorbed from plasma by preaponeurotic fat. Clinical Relevance: The results provide baseline information for studies of the physiological features of orbital fat in normal and diseased conditions.