AUTHOR AND EDITOR INFORMATION

Section 1 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

INTRODUCTION

Section 2 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Background

Dermoid and epidermoid cysts are examples of choristomas, tumors that originate from aberrant primordial tissue. These tumors contain normal-appearing tissue in an abnormal location. As two suture lines of the skull close during embryonic development, dermal or epidermal elements are pinched off and form cysts, which are adjacent to the suture line. Approximately 50% of these tumors that involve the head are found in or adjacent to the orbit.

Pathophysiology

Orbital dermoid cysts may displace structures in the orbit, especially the globe. If the displacement is great, interference with vision by compression of the optic nerve may result or ocular motility may be disturbed, resulting in diplopia.

Mortality/Morbidity

• Orbital dermoid cysts almost never cause death.
• Morbidity is usually of a cosmetic nature; more rarely, proptosis and diplopia may result. A traumatically ruptured dermoid may result in dramatic orbital and periocular inflammation.

Age

These tumors more commonly are noted initially in young children; however, they may appear or grow at any age.

CLINICAL

Section 3 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

History

• Patients generally complain of a mass, which is visible in the orbital area. Growth of these lesions is generally slow.
• In adults, dermoids may become symptomatic for the first time and grow considerably over a year. Based on this fact, some workers conclude that these lesions may be dormant for many years or have intermittent growth.

Physical

• Children
• • The most common location is in the superior temporal aspect of the orbit.
  • The mass is generally less than 1 cm in diameter, nontender, and oval-shaped.
  • Usually, little displacement of the globe occurs.
  • Because it has no attachment to the skin, it can be differentiated from a sebaceous cyst. The cyst usually is tethered to the periosteum of the bone near suture lines, including the sinuses or intracranial cavity.
• Adults: The cysts are palpated less easily and have more vague borders. They are more likely to displace the globe, possibly growing or eroding their way into adjacent structures.
• Inflammation
• • If the cyst ruptures, either spontaneously or with trauma, a pronounced inflammatory response will occur that may mimic orbital cellulitis.
  • The inflammation may be suppressed by corticosteroids, but excision is required to prevent recurrence.
• Neurologic findings
• • Rarely, the cyst may press on the optic nerve and create the typical symptoms of optic nerve compression, as follows: reduced visual acuity, reduced color and brightness perception, and a relative afferent pupillary defect.
  • More rarely, the cyst may induce diplopia by physically restricting movement of the globe or by compressing cranial nerves III, IV, or VI.

Causes

• No known causes exist.
• Other diagnostic considerations
• • Ruptured dermoid cysts may mimic rhabdomyosarcoma.
  • Pediatric metastatic cancers
  • Orbital cellulitis

DIFFERENTIALS

Section 4 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Other Problems to be Considered

Mucocele
Encephalocele
Echinococcus cyst
Sebaceous cyst

WORKUP

Section 5 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Imaging Studies

• X-ray films often show radiolucent defects where the cyst has eroded into the bone. These defects can be large with distinct margins and may show sclerotic changes.
• CT or MRI studies have largely supplanted plain x-ray studies for evaluating dermoid cysts. These studies may be indicated, if the posterior extent or the cyst cannot be palpated.
• Orbital ultrasound may be useful and avoid the need for the more expensive CT or MRI studies.

Histologic Findings

The external layer of the cyst has variable thickness and may be exceedingly thin. The cyst is connected to periorbita by fibrovascular tissue. Epidermoid cysts have a lining of epithelial cells, usually stratified, that produce keratin. Dermoid cysts contain blood vessels, fat, collagen, sebaceous glands, and hair follicles. The material in the cyst varies from a tan oily liquid to a white or yellow substance that resembles cottage cheese or even a relatively solid mass. Often, high cholesterol content is present. The cysts commonly are inflamed and may contain free blood.

TREATMENT

Section 6 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Medical Care

• No medical care usually is required.
• Inflammation that results from a ruptured dermoid cyst may be controlled with prednisone.

Surgical Care

• Dermoid cysts usually are cosmetic problems; excise completely using an approach that is appropriate to the location in the orbit.
• Inflammation from preoperative or interoperative rupture of the cyst can be controlled by prednisone. The entire cyst must be excised to avoid persistent inflammation, a draining sinus, or recurrence of the cyst.

MEDICATION

Section 7 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

The goals of pharmacotherapy are to reduce morbidity and to prevent complications.

Drug Category: Corticosteroids

Have anti-inflammatory properties and cause profound and varied metabolic effects. Corticosteroids modify the body's immune response to diverse stimuli.

FOLLOW-UP

Section 8 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Further Outpatient Care

• After surgical excision, infrequent follow-up care is necessary.

Complications

• Orbital dermoid cysts may cause neurologic complications if they compress the optic nerve or cranial nerves III, IV, or IV.
• If the cyst ruptures, a marked inflammatory response follows.
• • Operative complications are no different from other orbitotomy procedures.
  • Damage to the eye or adnexal structures, motility restriction, infection, inflammation, and hemorrhage may occur.

• The dermoid cyst may displace the globe, depending on the cyst's location.

Prognosis

• Dermoid cysts generally have a benign prognosis.
• • If they are excised completely, usually only a minimal scar occurs.
  • If they are observed rather than excised, slow growth can be expected.

Patient Education

• Patients should understand that these tumors are benign.
• Tell patients that surgery generally is successful, but that serious complications can be associated with any orbitotomy (eg, ptosis, diplopia, blindness, death).

MULTIMEDIA

Section 9 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Media file 1:  Temporal-zygomatic suture line on the lateral orbital wall. The location of the periosteal attachment of most orbital dermoids.
	View Full Size Image
Media type:  Photo

REFERENCES

Section 10 of 10

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

• Chawda SJ, Moseley IF. Computed tomography of orbital dermoids: a 20-year review. Clin Radiol. Dec 1999;54(12):821-5. [Medline].
• Leone CR, Grove AS, Lloyd W, et al. Atlas of Orbital Surgery. WB Saunders Co; 1992.
• McNab A. Manual of Orbital and Lacrimal Surgery. Butterworth-Heinemann Medical; 1998.
• Rootman J. Orbital Surgery: A Conceptual Approach. Raven Press; 1995.
• Schick U, Hassler W. Pediatric tumors of the orbit and optic pathway. Pediatric Neurosurg. 2003;38(3):13-21. [Medline].
• Shields JA, Shields CL. Orbital cysts of childhood--classification, clinical features, and management. Surv Ophthalmol. May-Jun 2004;49(3):281-99. [Medline].
• Shields JA, Shields CL, Scartozzi R. Survey of 1264 patients with orbital tumors and simulating lesions: The 2002 Montgomery Lecture, Part 1. Ophthalmology. May 2004;111(5):997-1008. [Medline].
• Stephenson C. Ophthalmic Plastic, Reconstructive, and Orbital Surgery. Butterworth-Heinemann Medical; 1997.

Article Last Updated: Aug 16, 2006