Periorbital dermoid cysts are common, non-cancerous growths that appear near the eye. Understanding these cysts is helpful for managing them effectively. They are present from birth, though they may not be noticed immediately.
Understanding Periorbital Dermoid Cysts
A periorbital dermoid cyst is a benign mass that forms when skin cells and other tissues become trapped during early embryonic development. These cysts are congenital. This entrapment usually occurs along the lines where embryonic tissues fuse.
The cyst itself is lined with skin-like epithelium, containing structures such as hair follicles, sebaceous glands, and sometimes even sweat glands. These glands continue to produce substances like oil and shed old skin cells, causing the cyst to enlarge over time. Periorbital dermoid cysts are most commonly found in the upper outer quadrant of the orbital rim, often near the lateral eyebrow or lacrimal fossa. They are distinct from other types of cysts because of their specific embryonic origin and the presence of these mature skin elements within their capsule.
Identifying Symptoms
Periorbital dermoid cysts usually present as a smooth, soft lump under the skin, often near the eyebrow or outer corner of the eye. These masses are painless and can be moved, although some may be fixed to the underlying bone. Their size can vary, commonly ranging from 1 to 5 centimeters.
While present at birth, these cysts may not become noticeable until infancy or early childhood. Although many periorbital dermoid cysts are asymptomatic, complications can arise if they are left untreated. Potential issues include enlargement, which can cause pressure on the eyeball leading to discomfort or visual problems, and in some cases, can even change the shape of nearby bones. If the cyst ruptures, its contents can leak into the surrounding tissues, causing an inflammatory response characterized by pain, redness, and swelling. Infection is another complication.
How They Are Diagnosed and Treated
The diagnostic process for a periorbital dermoid cyst typically begins with a physical examination by a healthcare provider. During this examination, the doctor can often feel the soft, painless mass and assess its size, shape, and mobility under the skin. The characteristic location, often in the outer third of the eyebrow, helps in the initial assessment.
To confirm the diagnosis and gain a more complete understanding of the cyst, imaging tests are frequently employed. Computed tomography (CT) scans or magnetic resonance imaging (MRI) provide detailed images that help determine the cyst’s exact size, depth, and its relationship to surrounding structures, particularly bone. These scans are especially helpful in identifying any bony defects, tunnels, or deeper extensions, such as into the orbit or skull, which can influence the surgical approach.
The primary treatment for periorbital dermoid cysts is surgical removal. Surgery is recommended to prevent potential complications like infection, rupture, or bone erosion, and for cosmetic reasons. The procedure aims for complete excision of the cyst, including its capsule, to minimize the risk of recurrence. For smaller, superficial cysts, a simple excision may be performed. However, larger or deeper cysts, especially those with bone involvement or intracranial extension, may require a more extensive surgical approach, guided by prior imaging studies.
What to Expect After Treatment
Following surgical removal of a periorbital dermoid cyst, the recovery period is straightforward. Wound care instructions will be provided, which involve keeping the incision site clean and protected. Pain management involves over-the-counter medications acetaminophen or NSAIDs.
Scarring is a possibility, though surgeons aim to minimize its appearance by making incisions along natural skin creases. Once the cyst is completely removed, the prognosis is excellent, and recurrence is rare. Studies indicate recurrence rates for lateral brow dermoid cysts can be as low as 0% to 1.4%, and for orbital dermoid cysts, around 1.8%. These cysts are benign, meaning they are not cancerous, and successful treatment provides a positive long-term outlook.