Orbital dermoid cyst
Citation, DOI & article data
Orbital dermoid cysts are congenital lesions representing closed sacs lined by an ectodermal epithelium and comprising the most common orbital mass in children. They are typically divided into deep (within the orbit) and superficial (adjacent to the orbital rim).
They comprise ~2% of orbital tumors 5. Superficial location is much more frequent.
Superficial angular dermoid is usually diagnosed relatively early. As they grow slowly, less than 25% of them are identified at birth, and they usually manifest in the first decade of life. Clinical features include a painless subcutaneous mass along the zygomaticofrontal and the frontoethmoidal sutures 1,3.
It is important to note that more than 80% occur in the upper outer quadrant or the lacrimal fossa (external angular dermoid) 1.
Deep dermoids tend to be diagnosed later in life with accompanying proptosis 6.
Dermoid cysts are thought to occur as a developmental anomaly in which embryonic ectoderm and mesoderm are trapped in the closing neural tube between the 5th-6th weeks of gestation 1,3.
Stratified squamous epithelium lines dermoid cysts, as in epidermoid cysts, which are both considered ectodermal inclusion cysts. Unlike epidermoid cysts, however, they also have adenxal tissues derived from mesoderm, such as hair follicles, sweat glands, and sebaceous glands. The latter is responsible for the secretion of sebum which imparts the characteristic appearance of these lesions on CT and MRI.
These lesions are usually extraconal, non-enhancing masses with smooth margins, cystic and/or solid components. They are typically heterogeneous with soft tissue, fluid and fatty (sebum) components; occasionally calcifications may be present.
Ruptured dermoids may show adjacent inflammatory changes.
Treatment and prognosis
Treatment and prognosis depend on size, location and involvement of orbital structures. While superficial lesion may barely require a cosmetic excision, a deeper one may require more invasive methods involving micro-dissection, orbitotomy, and rarely, intracranial exploration if the lesion extends to that extent 7.
Possible differential considerations include
- orbital epidermoid cyst
- usually large lesions and associated with a facial deformity
- multiloculated cystic masses
- calcification, fat, and/or ossification may be present
- orbital dermolipoma
- orbital hemangioma
See main article
- 1. Chung EM, Murphey MD, Specht CS et-al. From the Archives of the AFIP. Pediatric orbit tumors and tumorlike lesions: osseous lesions of the orbit. Radiographics. 2008;28 (4): 1193-214. Radiographics (full text) - doi:10.1148/rg.284085013 - Pubmed citation
- 2. Karcioglu ZA. Orbital Tumors. Springer. (2014) ISBN:149391510X. Read it at Google Books - Find it at Amazon
- 3. Jung WS, Ahn KJ, Park MR et-al. The radiological spectrum of orbital pathologies that involve the lacrimal gland and the lacrimal fossa. Korean J Radiol. 2007;8 (4): 336-42. Free text at pubmed - Pubmed citation
- 4. Vashisht S, Ghai S, Hatimota P, Ghai S, Betharia S M. Cystic lesions of the orbit : A CT spectrum. Indian J Radiol Imaging [serial online] 2003 [cited 2015 Jun 26];13:139-44. Available from: http://www.ijri.org/text.asp?2003/13/2/139/28646
- 5. Kudo K, Tsutsumi S, Suga Y et-al. Orbital dermoid cyst with intratumoral inflammatory hemorrhage: case report. Neurol. Med. Chir. (Tokyo). 2008;48 (8): 359-62. Pubmed citation
- 6. Ahmed RA, Eltanamly RM. Orbital epidermoid cysts: a diagnosis to consider. J Ophthalmol. 08;2014: 508425. doi:10.1155/2014/508425 - Free text at pubmed - Pubmed citation
- 7. Chaudhry IA. Management of deep orbital dermoid cysts. Middle East Afr J Ophthalmol. 2008;15 (1): 43-5. doi:10.4103/0974-9233.53376 - Free text at pubmed - Pubmed citation