A corneal leukoma is a dense, white opacity that forms on the cornea, the transparent front surface of the eye. The term leukoma originates from the Greek word “leukos,” meaning white. This scar tissue disrupts the normal transparency of the cornea, scattering or blocking light from properly entering the eye. This can lead to significant visual impairment or a complete loss of vision, depending on the scar’s size and location.
Underlying Causes of Corneal Scarring
A corneal leukoma is the eye’s response to significant injury or disease that damages corneal tissue. One of the most common pathways is infection. Bacterial, fungal, or viral agents, such as the herpes simplex virus, can create inflammation and tissue damage that the body repairs with opaque scar tissue after the infection subsides.
Physical trauma is another frequent cause of corneal scarring. A penetrating injury that breaches the corneal layers, a chemical burn, or complications from eye surgeries can all initiate a scarring response. The body’s healing mechanisms are not designed to restore perfect transparency, and the resulting fibrous tissue forms a dense leukoma.
Corneal ulcers, which are open sores on the cornea’s surface, also lead to leukomas. These ulcers often arise from untreated infections, severe dry eye syndrome, or improper use of contact lenses. As the ulcer heals, the body fills the defect with scar tissue that lacks the organized structure of healthy corneal tissue, resulting in a permanent opacity.
In some instances, the cause is genetic or related to systemic health issues. Congenital conditions can mean a leukoma is present at birth, while certain inherited corneal dystrophies can cause opacities to develop over time. A severe deficiency in Vitamin A can also impair corneal health and contribute to scarring.
Recognizing the Signs and Getting a Diagnosis
The most apparent sign of a corneal leukoma is a visible white or grayish spot on the surface of the eye. This opacity can range from a small dot to a large patch covering most of the cornea. Depending on its location, especially if it is centered over the pupil, it can cause a significant decrease in vision, making images appear blurry or completely obscured.
Individuals may also experience other symptoms related to how the scar tissue affects the eye’s function. A high sensitivity to light, known as photophobia, is common because the scar scatters light irregularly. Some people report a persistent feeling of pain, irritation, or the sensation that something is stuck in their eye. In some cases, the scar tissue can alter the cornea’s curvature, leading to astigmatism.
An ophthalmologist diagnoses a corneal leukoma through a detailed eye examination. This includes a visual acuity test to measure how much the opacity is affecting the sharpness of vision. The definitive diagnostic tool is the slit-lamp examination, which uses a high-magnification microscope to inspect the layers of the cornea. This allows the doctor to assess the scar’s size, depth, and density to determine the best course of action.
Available Treatment Options
Treatment for a corneal leukoma is determined by the severity of vision loss and the scar’s characteristics. For leukomas that cause severe visual impairment, the most common treatment is a corneal transplant, also known as keratoplasty. This surgical procedure involves removing the damaged, opaque corneal tissue and replacing it with a clear, healthy cornea from a donor. The specific technique used depends on the depth of the scar.
A full-thickness transplant, or Penetrating Keratoplasty (PKP), involves replacing all the layers of the central cornea and is used for deep and extensive scars. For scars that affect only the front layers of the cornea, a partial-thickness transplant, such as Deep Anterior Lamellar Keratoplasty (DALK), may be performed. DALK preserves the patient’s own innermost layer (the endothelium), which can reduce the risk of tissue rejection.
In cases where the leukoma has caused irreversible vision loss and there is no potential for sight restoration, treatment may focus on cosmetic improvement. Corneal tattooing, a procedure called keratopigmentation, can be used to improve the eye’s appearance. In this procedure, a specialized pigment is injected into the corneal tissue to color the white scar, making the leukoma much less noticeable.
Prosthetic or specialized contact lenses offer a non-surgical option for managing a leukoma. A custom-made, opaque contact lens can be designed to cover the white scar, providing a more natural appearance by mimicking a healthy pupil and iris. These lenses can also serve a functional purpose by blocking excess light from entering the eye through the scarred cornea, which helps to reduce glare and light sensitivity.
For leukomas that are very superficial, a laser-based procedure known as Phototherapeutic Keratectomy (PTK) may be an option. This technique uses an excimer laser to precisely remove thin layers of scar tissue from the cornea’s surface. By vaporizing the opaque tissue, PTK can sometimes restore a degree of clarity to the cornea and improve vision, but it is only suitable for scars that do not extend deep into the corneal structure.