The transparent, protective outermost layer of the human eye is known as the cornea. It is a smooth and dome-shaped tissue layer. Cornea’s main job is to protect your eyes by controlling the amount of light that enters into the eye and blocking the entry of debris.

The cornea also helps focus your vision. It is a resilient tissue and can heal itself from minor abrasions. However, any significant damage to the cornea can result in a person developing a corneal scar.

Corneal scars are typically caused due to improper usage of contact lenses, burns, lacerations, deep scratches, and syphilis and shingles (very rare).

Any significant damage to the cornea results in the scar tissues replacing the clear corneal tissue or cornea being impeded by the formation of new blood vessels (neovascularization). These scars impair the vision.

If you think that you might be having corneal scarring, visit your ophthalmology who will determine the next course of action.

Corneal Scarring Symptoms

Some of the common symptoms of corneal scars include:
  • Blurred vision
  • Excessive tearing
  • Pain
  • A scratching or burning sensation in the eye
  • Eyelid swelling
  • Feeling the presence of some irritant in the eye
  • Red eyes
  • Light sensitivity

Diagnosis of Corneal Scarring

Corneal scars are diagnosed by a detailed diagnostic test conducted in an outpatient setting. Your ophthalmologist first takes down a thorough medical history.

Next, an eye exam is administered by the ophthalmologist. During the exam, the ophthalmologist looks for any irritating debris or abrasions which might be hidden under the eyelids. Tools like slit lamp or ophthalmoscope are used to get a better picture of the eye.

Depending on the severity, the ophthalmologist can also use fluorescein eye stain, in which a blue light and orange dye are used to detect the presence of any foreign body or any damage to the eye.

Treatment of Corneal Scarring

Prevention is better than cure. And preventing scars from developing is the most efficient and easiest way of treating a corneal scar.

Ophthalmologists can also use an immune-suppressive drug to treat scar formation after treating corneal ulcers or infection. If the scar becomes a part of your cornea and affects the vision, your ophthalmologist may recommend treatment.

If the cornea distorts the focusing ability or makes the corneal surface irregular, then the ophthalmologist generally recommends specialty contact lenses. These lenses smoothen the corneal surface. However, these are suitable if the scars are present on the side and not in the center of your vision.

If the scar is in the center, then it needs surgical removal. Some of the surgical options include
  • Superficial Keratectomy
  • Descemet’s Membrane Endothelial Keratoplasty (DMEK)
  • Penetrating Keratoplasty
  • Deep Anterior Lamellar Keratoplasty (DALK)
Superficial Keratectomy (SK) is not a corneal transplant in its truest sense. SK is typically used for opacities present in the epithelium (cornea’s outermost layer).

The corneal epithelium can regenerate every week. SK removes the unhealthy epithelium which is replaced by the new corneal epithelium.

Doctors sometimes recommend the removal of peripheral superficial opacity if they feel it will grow towards the center.

Penetrating Keratoplasty (PK), DALK, and DMEK are corneal transplants. These procedures involve the removal and replacement of opaque tissue present in different corneal layers.

Depending on the severity, the corneal surgeon will remove only the unhealthy layer and leave healthy tissue behind to help regeneration.

Compared to DALK and PK, DMEK has lesser risk and is less invasive, making it the most preferred choice of corneal surgeons. PK and DALK is the last resort.