Cornea Transplantation

Cornea Transplantation

Operation goal:

It is the replacement of the affected cornea of ​​the eye, as a result of its exposure to many factors, which can lead to diseases or permanent and irreparable damage. The cornea for transplantation is taken from a dead donor, while this is the most common procedure among various organ transplants.

Cornea

It is that transparent part that covers the eye from the outside, and protects it from the entry of pollution, dirt, and other things. The function of the cornea is to refract light rays as they enter the eye, so it plays an important role in the retina's ability to focus an image.

Damage to the cornea may be caused by infectious diseases such as: the herpes virus, which causes ulcers in the cornea, bacterial infection, fungi, and others. But one of the other widespread injuries to the cornea is the injury to the eye due to the entry of a foreign body that causes the cornea to be injured in a way that it cannot cure. There are also some eye diseases that may cause a variation in the shape of the cornea: curvature or concavity of the cornea, which affects the ability to see, and sometimes leads to blindness. In such cases, the patient needs a new corneal transplant (eg, keratoconus, cataract). This process is not simple, so it is only resorted to after all other preventive treatments have failed.

Corneal transplant

There are several methods used for corneal transplant surgery. The old method involves removing the affected cornea completely and stabilizing the healthy cornea with sutures (sutures). And when modern methods are used, in which precise devices such as lasers are used, only part of the cornea is removed (DSEK). Also, there are other types of corneal transplant procedures.

Prepare for the operation:

There is no need to match the tissue and blood type when performing corneal transplantation surgery, because there are good treatments that are given to the patient after transplantation, which contribute to the acceptance of the transplanted organ with a high success rate of about 90%. Another reason why such a fit is not needed is that the cornea is a tissue that is not attached to a blood vessel.

In most cases, there is no need for a general examination before surgery. The ophthalmologist performs a comprehensive examination of the eyes, which includes checking vision, pressure inside the eyes, visual acuity and examining the fundus, in order to ensure the integrity of the retina.

The cornea is transplanted under local or general anesthesia. The doctor should also be consulted with regard to all medications that the patient should stop taking before the operation date. Also, there is a need to fast for 8 hours before the operation.

process:

After instillation of the dilating material into the pupil, local anesthesia is administered to the area or general anesthesia if necessary. According to the traditional method, the surgeon makes a small, thin incision in the cornea, and then removes all corneal tissue. After that, the surgeon sutures the transplanted cornea in its place.

In modern methods of corneal transplantation surgery, there is not always a need to transplant the entire cornea, and only the lining of the cornea can be transplanted (if it is injured) or another part of the cornea is implanted using accurate and modern devices. In laser-based surgery, the cornea that will be transplanted is cut according to the required size and the extent of damage to the original cornea. Then they are fixed - sometimes without the need for stitches -. At the end of the operation, a bandage is placed over the eye.

The surgery takes one to two hours (depending on the type of surgery).

Risks of surgery:

Risks of surgery in general:

Incision contamination - often superficial and topically treated. But in some rare cases, it may lead to a more serious eye infection. Sometimes the doctor may have to open the incision again in order to get rid of the remnants of bacteria.

Bleeding - Mostly, bleeding occurs in the surgical area as a result of local tissue damage. Bleeding is caused by a rupture of a blood vessel in the eye.

Scarring - No traces or scars should remain in the cornea, as the suture area is very small and thin. But in some cases, there is a defect in the healing process (healing) and this results in the emergence of a scar, which makes the vision blurred in the cornea that was transplanted.

Anesthesia risks - such phenomena are often caused by sensitivity to anesthetic drugs. In very rare cases, a dangerous reaction may occur that leads to a drop in blood pressure (anaphylactic shock).

Ocular risks in corneal transplantation:

Dry eyes - this can be overcome by using appropriate eye drops.

Sensitivity to light - this phenomenon is expected to continue for a short period (up to a month) after surgery.

Acute rejection of the transplanted cornea - This phenomenon is when the body has an acute immune reaction to the transplanted cornea. However, it is possible today to give the patient anti-immune drugs, if that happens.

Post-operative treatment:

After corneal transplant surgery, the patient stays in the hospital under observation for one or a few nights. When modern surgical methods are used, patients are sometimes able to leave the hospital earlier. The patient is instructed on how to use eye drops that contain antibiotics to prevent infection, which he should use for 3 weeks after the operation. The patient is provided with eye drops to prevent eye infection and to suppress the immune system.

The patient can take pain relievers as needed. While the recovery period is related to the type of corneal transplantation that was followed, as this period is short when using modern methods.

The sutures (sutures) are removed if they are used in surgery, after a few months have passed (in traditional corneal transplant surgery).

In the following cases, the patient should go directly to the doctor: persistent pain despite the use of analgesics, eye secretions, bleeding from the eye, or a high temperature.