The color difference in orbital fat

Objective: To identify and quantify carotenoids found in white and yellow o rbital fat. Methods: Specimens of nasal (white) and preaponeurotic (yellow) orbital fat were obtained from patients during upper eyelid blepharoplasty. Carotenoid s and retinoids were extracted and subjected to spectral and high-performan ce liquid chromatography analyses. Results: The chromophore content of extracts from unsaponified fat, as meas ured by absorbance at 425 nm per gram of fat, was 2- to 4-fold higher in pr eaponeurotic fat than in nasal fat. High-performance liquid chromatography analysis from enzymatically digested fat revealed large amounts of lutein, beta -carotene, and retinol and small amounts of other unidentified caroten oids. The amount of beta -carotene and lutein in preaponeurotic fat was app roximately LC-fold higher than in nasal fat. Conclusions: The higher carotenoid content of preaponeurotic fat might caus e it to be more yellow than other orbital fat, and lutein and p-carotene mi ght be selectively absorbed from plasma by preaponeurotic fat. Clinical Rel evance: The results provide baseline information for studies of the physiol ogical features of orbital fat in normal and diseased conditions.