An orbital prosthesis is a custom-made, removable device that artificially restores the eye, eyelids, and adjacent bone and soft tissue structures. This type of prosthesis is designed to cosmetically replicate the natural appearance of the orbital region for individuals who have lost these features. The device consists of a flexible silicone component that mimics the eyelids and skin, and an acrylic ocular part that replicates the eye itself.
Reasons for an Orbital Prosthesis
The most common reason for needing an orbital prosthesis is a surgical procedure known as orbital exenteration. This involves the removal of the entire contents of the eye socket, including the eyeball, muscles, fat, and eyelids. This operation is performed to treat malignant tumors that have invaded the orbital space, such as melanomas, squamous cell carcinomas, or basal cell carcinomas.
In other cases, severe physical trauma can cause irreparable damage to the eye and surrounding structures, making removal a medical necessity. Aggressive infections that do not respond to other treatments and threaten to spread may also require an exenteration. While less frequent, some individuals are born with congenital defects of the orbital region that necessitate a prosthesis.
The Prosthesis Creation Process
The fabrication of an orbital prosthesis is handled by a specialist known as an anaplastologist. The initial step involves taking a precise impression of the patient’s orbital defect and the surrounding facial topography. This can be done using traditional materials like alginate or with modern digital scanning techniques to capture the exact contours of the anatomy. This impression is used to create a master cast.
From this cast, a wax model is sculpted. This wax pattern is carefully shaped and refined during a fitting appointment, allowing the patient and anaplastologist to make adjustments to ensure the best possible aesthetic and fit. Once the wax sculpture is approved, color matching begins. The anaplastologist pigments the medical-grade silicone to match the patient’s specific skin tones, incorporating subtle variations for a lifelike appearance. A custom-made acrylic ocular component is also created and colored to match the patient’s remaining eye.
The pigmented silicone is packed into a mold created from the wax pattern and allowed to cure for approximately 24 hours. After curing, the finished prosthesis is removed, trimmed, and polished. In a final delivery appointment, the prosthesis is fitted, and any last-minute color adjustments are made. The patient also receives detailed instructions on how to insert, remove, and care for their new device.
Methods of Attachment
Several methods are used to secure an orbital prosthesis, each offering different levels of convenience and stability. The most common non-invasive option is the use of medical-grade skin adhesives. These liquid adhesives are applied to the back of the silicone prosthesis, which is then pressed into place. This method requires daily application and removal.
Another method involves attaching the prosthesis to an eyeglass frame. This technique uses the structure of the glasses to hold the prosthesis securely against the face. It is a practical choice for patients who already wear glasses, integrating the prosthesis discreetly with their eyewear.
For the most secure and stable attachment, osseointegrated implants may be used. This involves a surgical procedure where small titanium implants are placed directly into the bone surrounding the orbit. Over a healing period of three to six months, the bone fuses with the implants in a process called osseointegration. Once healed, the prosthesis, fitted with magnets or clips, can be snapped onto the implants, providing a very secure fit that is easy to attach and remove.
Daily Care and Longevity
Proper maintenance is important to the comfort and longevity of an orbital prosthesis. Daily cleaning of both the prosthesis and the underlying skin and implant sites is necessary to prevent irritation and infection. The prosthesis can typically be cleaned with mild soap and water. It is important to avoid alcohol-based products on the ocular component, as they can cause the acrylic to crack.
The typical lifespan of a silicone orbital prosthesis is between one and three years. Over time, the silicone material can degrade, and the colors may fade due to exposure to UV light and environmental factors. Changes in the patient’s facial structure can also affect the fit of the prosthesis. Regular follow-up appointments with an ocularist, often every six months, are recommended to professionally polish the prosthesis and check the health of the surrounding tissue.