How to Diagnose a Dermoid Cyst

A dermoid cyst is a hamartomatous tumor covered with a thick dermis-like wall. It contains sebaceous glands in addition to almost all other skin adnexa and may also contain nail and dental structures depending on the location. Dermoid cysts on the skin usually occur on the face and neck but can grow internally as well. The following steps will show how to diagnose a dermoid cyst.

Instructions

1. Locate most congenital dermoid cysts with a visual inspection. A unilateral swelling in the upper eyelid may indicate a dermoid cyst arising from a tear duct.

2. Expect dermoid cysts to occur most commonly as cutaneous cysts on the forehead around the eyes with a diameter of 1 to 4 cm. The inside of the mouth also is a common location.

3. Detect most internal dermoid cysts after gynecological or neurological complaints. Gynecologically related dermoid cysts primarily occur as a cystic ovarian tumor and neurologically related cysts often grow on the spine or intracranially.

4. Distinguish cutaneous dermoid cysts from epidermal cysts. Dermoid cysts are lined with an epidermis that contains various epidermal appendages, usually fully mature. They also may be misdiagnosed as skin cancer.

5. Use multiple imaging techniques for diagnosing internal dermoid cysts. Radiography, Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) all are used effectively. An MRI is especially useful in diagnosing intracranial dermoid cysts and also may be required to differentiate a giant dermoid cyst on the neck with a cystic hygroma.