Eye

Orbit & optic nerve

Subconjunctival herniated orbital fat



Last author update: 1 November 2016
Last staff update: 13 May 2021

Copyright: 2002-2024, PathologyOutlines.com, Inc.

PubMed Search: Subconjunctival herniated orbital fat


Ivy John, M.D.
Page views in 2023: 887
Page views in 2024 to date: 165
Cite this page: John I. Subconjunctival herniated orbital fat. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/softtissueadiposeshof.html. Accessed March 19th, 2024.
Definition / general
  • Rare entity; first described in path literature in 2007 (Am J Surg Pathol 2007;31:193)
  • Prolapsed intraconal fat due to dehiscence of tenon capsule precipitated by age, disease, trauma or surgery
  • Typically occurs in elderly obese men
  • Presents as small (up to 2.5 cm), raised, convex, yellow, compressible mass in the superotemporal quadrant of the eye (Optom Vis Sci 2015;92:1021, Figure 1 & 2)
  • Unilateral or bilateral
  • Low recurrence rate after simple excision
Essential features
  • Rare entity, caused by forward movement of intraconal fat due to dehiscence of tenon capsule precipitated by age, disease, trauma or surgery
  • Typically presents in elderly obese men as a small, raised, yellow, compressible mass in the superotemporal quadrant of the eye
  • Composed of an admixture of mature adipocytes, delicate fibrovascular septae, Lochkern cells and floret-like giant cells
  • Principal differential diagnosis includes pleomorphic lipoma and atypical lipomatous tumor
Case reports
Clinical images

Images hosted on other servers:

Prolapsed orbital fat

Microscopic (histologic) description
  • Composed of uniformly shaped mature adipocytes separated by a delicate fibrovascular septae
  • Scattered Lochkern cells (adipocytes with enlarged nuclei containing intranuclear vacuoles) and floret-like giant cells (multinucleated giant cells with a wreath like arrangement of bland, uniform, often vacuolated nuclei)
  • Varying numbers of inflammatory cells, including lymphocytes, plasma cells, histiocytes and mast cells
Microscopic (histologic) images

Contributed by Ivy John, M.D.

Herniated orbital fat

Positive stains
Differential diagnosis
  • Pleomorphic lipoma:
    • Different location; PL often involves soft tissues of back and shoulder of elderly men
    • Areas typical of spindle cell lipomas, including variably myxoid stroma, wire-like collagen and bland spindle cell proliferation are focally present
    • Floret-like giant cells show notable nuclear enlargement and hyperchromasia
  • Well differentiated liposarcoma:
Board review style question #1
Regarding subconjunctival herniated orbital fat, which of the following statements is true?

  1. Associated with MDM2 amplification
  2. Floret-like giant cells with nuclear hyperchromasia and pleomorphism are typically seen in SHOF
  3. Nuclei of Lochkern cells and floret-like giant cells are highlighted by CD34 immunohistochemistry
  4. Has an aggressive course and the management includes radiation therapy
Board review style answer #1
C. The nuclei of Lochkern cells and floret-like giant cells in SHOF are highlighted by CD34 immunohistochemistry (although not necessary for diagnosis)

Comment Here

Reference: Subconjunctival herniated orbital fat
Back to top
Image 01 Image 02