What is Corneal Transplantation? When is it Performed?

A corneal transplant (keratoplasty) is a surgical procedure used to restore the clarity and transparency of the cornea, often performed on individuals who experience vision loss due to corneal diseases. Corneal diseases refer to conditions in which the corneal layer is damaged, which, if left untreated, can lead to permanent vision problems. Therefore, a corneal transplant is considered an important option to improve the patient’s quality of life and restore eye health.

What is the Cornea?

The cornea is a thin, transparent layer covering the outer surface of the eye, helping to refract light that enters the eye, thus representing the first step in the visual process. It assists in properly directing light onto the eye’s lens, contributing to clear vision. Composed of uniquely arranged cells, the cornea is highly transparent, allowing light to pass through to the internal structures of the eye. Additionally, it acts as a barrier, protecting the eye from external factors, infections, and other harmful elements, making it essential for eye health. However, the cornea can sometimes become damaged due to various factors such as infections, injuries, or hereditary conditions. Corneal damage can cause visual impairments and even pain. In advanced cases, these injuries may require corneal transplantation.

What is Corneal Transplantation?

Corneal transplantation is a surgical procedure that aims to replace the damaged cornea, which can be due to various reasons affecting eye health, with a healthy cornea. The cornea, forming a clear tissue that covers the eye’s front region, plays a crucial role in clear and healthy vision. However, in some cases, corneal diseases or injuries can impair it, leading to vision loss. Corneal transplantation is performed to restore visual comfort and clarity for the patient. The procedure is carried out by an eye specialist and usually performed under local anesthesia. During the procedure, the damaged cornea is removed and replaced with a healthy cornea from a donor.

How are Corneal Diseases Diagnosed?

Corneal diseases can cause vision loss, making early diagnosis and prompt treatment crucial. A corneal disease diagnosis is performed by an eye doctor. An eye examination is the fundamental step in evaluating overall eye health. After listening to the patient's medical history and symptoms, the doctor carefully examines the cornea, eyelids, and the eye’s external surface. Following this, the doctor may recommend eye scans or imaging tests for a more detailed assessment of the cornea. Symptoms of corneal diseases include eye pain, redness, blurred vision, light sensitivity, and either excessive or reduced tear production, which can provide essential clues for accurate diagnosis. Some corneal diseases, particularly infections, may be diagnosed through laboratory tests of eye fluids, which can help identify the microorganism causing the infection. In rare cases, a corneal biopsy may be required for a

Who Can Receive a Corneal Transplant?

A corneal transplant can be an effective treatment option for individuals experiencing vision problems or at risk of vision loss due to corneal diseases. The procedure is performed on those who meet certain criteria, as it may not be suitable for every patient. It is usually preferred for treating vision issues caused by corneal diseases. Corneal transplant may become an option in cases of progressive conditions like keratoconus, corneal dystrophy, corneal ulcers, and scarring. A second transplant may also be considered if a previous corneal transplant has failed or been rejected.

What Methods Are Used in Corneal Transplantation?

The corneal transplant procedure can be performed using three main methods, which involve replacing different layers of the cornea. These methods are selected based on the patient’s condition and the severity of the corneal disease:

• Full-thickness Corneal Transplant: The full-thickness corneal transplant is the most commonly used method. In this procedure, the entire damaged cornea is removed and replaced with a healthy, full-thickness donor cornea. This method is preferred, especially when the corneal disease affects all layers of the cornea.
• Middle Layer Corneal Transplant: Middle layer corneal transplant is a method where only the descemet membrane and inner layers of the cornea are replaced. The damaged inner layer is removed and replaced with a healthy inner layer from a donor.
• Anterior Layer Corneal Transplant: In an anterior layer corneal transplant, only the descemet membrane and a very thin inner layer are replaced. This transplant helps patients achieve faster and sharper vision recovery and is preferred in cases where the inner layer is damaged.

What Complications May Arise After Corneal Transplantation?

Although corneal transplantation is an effective surgical intervention to treat vision problems, as with any surgery, it may be associated with certain potential complications that can impact the recovery process and require close monitoring. First, as with any surgery, there is a risk of infection. Additionally, the cornea may be rejected by the patient, leading to vision loss, making regular follow-ups essential. The risk of high intraocular pressure (glaucoma) is another factor to consider after corneal transplantation, as it can pose a risk to eye health. Irregular surface issues, such as astigmatism, can blur vision and may require glasses or contact lenses. Problems during the healing process and vision difficulties are also possible complications after corneal transplantation. Therefore, regular doctor visits are important to ensure early diagnosis and treatment. Following the doctor’s recommendations before and after the surgery can help minimize the risk of complications.

Vision Recovery and Healing Time After Corneal Transplantation

Vision recovery after corneal transplantation can vary depending on the type of transplant and the patient’s initial eye health. Patients may experience significant vision blurriness in the first few days after the transplant, which is normal, as the corneal surface may not provide clear vision while the eye is healing. Swelling and irritation in the eye typically improve within the first few weeks. The full recovery period can vary depending on the patient’s general health, any complications after the transplant, and the technique used. Complete recovery and clear vision may take several months.

Precautions to Take After Corneal Transplantation

A careful recovery process is required after corneal transplantation. The following precautions should be taken:

• Following Doctor's Instructions: It is important to strictly follow the doctor's instructions after a corneal transplant. This includes using eye drops, changing eye dressings, and adhering to other recommendations. These instructions help speed up recovery and reduce the risk of complications.
• Protecting the Eyes: After a corneal transplant, the eyes should be protected from environmental factors. Avoiding direct exposure to sunlight and wearing protective glasses can help protect the eyes.
• Adhering to Hygiene Rules: Regular handwashing is essential to reduce the risk of infection. Care should be taken to clean hands before and after any contact with the eyes.

If you suspect corneal disease or believe you have an issue with your eye health, you should consult an eye doctor. Early diagnosis and treatment are critical to preventing the progression of corneal diseases and keeping them under control.