Subconjunctival fat prolapse is an acquired herniation of intraconal fat due to the weakening of the Tenon capsule by normal aging, surgery, or trauma. It presents clinically with a fat-containing epibulbar mass in the lateral canthal area.
Subconjunctival fat prolapse occurs mainly in elderly obese men with a mean age of 65 years (range 41-85 years).
They mostly present as unilateral or bilateral soft yellow color mass with a convex anterior margin and superficial fine blood vessels in the superotemporal quadrant or lateral canthus region, around the rectus muscle and below the lacrimal gland. It can be easily pushed back into the orbit with a cotton tip applicator and becomes more prominent by retropulsion of the globe.
Although rarely clinicians request imaging for further investigation of these lesions, both CT and MRI would demonstrate invariable continuation of these lesions with intraconal fat.
Treatment and prognosis
Usually, reassurance would be enough if there are no visual problems and no cosmetic concern exist.
Sometimes differentiation of subconjunctival fat prolapse from other entities is difficult clinically and because treatment and outcome are quite different radiological and ultimately histopathological confirmation is required for final diagnosis:
- 1. Kim E, Kim HJ, Kim YD et-al. Subconjunctival fat prolapse and dermolipoma of the orbit: differentiation on CT and MR imaging. AJNR Am J Neuroradiol. 2011;32 (3): 465-7. doi:10.3174/ajnr.A2313 - Pubmed citation
- 2. Skorin L, Rink C. Diagnosis and excision of subconjunctival herniation of orbital fat. Optom Vis Sci. 2014;91 (9): e236-40. doi:10.1097/OPX.0000000000000342 - Pubmed citation
- 3. Lin CC, Liao SL, Liou SW et-al. Subconjunctival Herniated Orbital Fat Mimicking Adipocytic Neoplasm. Optom Vis Sci. 2015;92 (10): 1021-6. doi:10.1097/OPX.0000000000000693 - Pubmed citation