Everything About Cornea Transplantation Rejection

Corneal transplantation is a method of removing part of diseased corneal tissue and replacing the donated cornea. The cornea has a transparent, dome-shaped surface through which light enters the eye, providing much of the eye’s ability for clear vision. With the help of corneal transplantation, vision is restored, eye pain is reduced and the appearance of the damaged cornea is restored. Most corneal transplant surgeries are successful. But like other surgeries, corneal transplant surgery may pose some complications and risks, one of which is the rejection of transplanted cornea. Rejection of corneal transplantation is one of the most common causes of corneal transplantation surgery failure. About 30% of transplanted corneas retract the cornea at least once, some of which end in corneal transplant surgery failure. Corneal transplant rejection may be reversible or irreversible. It can also affect corneal transplantation methods such as the full-thickness or layered method. However, the effect of corneal transplant rejection is less in layered transplantation. Keep reading on Moj Aramesh Amitis Health Tourism Company’s website to learn more about important tips you may want to know about cornea transplant rejection.

Possible Risks and Complications of Cornea Transplantation

Some complications may appear immediately after corneal transplantation, requiring emergency treatment. However, some complications may be revealed during subsequent visits to the doctor. These risks include:

• Cornea Rejection
• Eye infection
• Increased pressure in the eyeball (glaucoma)
• Problems with cornea sutures
• Retina problems such as detachment or swelling
• Bleeding from the transplant site

What is cornea transplantation rejection?

When the immune system does not recognize the cornea as part of the eye, corneal rejection occurs. Corneal rejection is one of the most common problems of corneal transplantation so that one out of every five transplants will have corneal rejection. But only about 5% of transplants are at risk of rejection. Corneal rejection may occur several months after corneal transplantation. But in some cases, it may occur a few weeks after the corneal transplant. Corneal rejection can often be effectively treated with steroid eye drops, provided treatment is started as soon as symptoms of corneal rejection are observed.

Symptoms of Corneal Rejection

Some common symptoms of corneal rejection are:

• Loss of vision or blurred vision
• Eye pain
• Red eyes
• Sensitivity to light

If you notice any of these symptoms, see your doctor or call an emergency immediately. Sometimes you may need medical treatment or another corneal transplant by observing these symptoms. In addition to the rejection of corneal transplantation, there is a risk of some other problems after corneal transplant surgery, such as:

• Astigmatism (an imperfection in the curvature of the eye)
• Retinal detachment (thin lining of the eye, called the retina, is separated from the blood vessels that are responsible for delivering oxygen and nutrients to the retina)
• Glaucoma (when eye fluid causes pressure on the eye)
• Uveitis (occurs due to inflammation of the middle layer of the eye)
• Recurrence of keratoconus
• Internal infection due to surgical wounds

Cornea rejection occurs in different forms:

The safety rejection of corneal transplantation includes various forms such as epithelial, sub-epithelial, endothelial, and mixed rejection. Epithelial rejection occurs in 2% of links. While the rejection under the epithelial has the lowest corneal graft rejection and occurs in about 1% of transplants. Sub-epithelial rejection occurs 2 to 6 years after corneal transplantation. The most common form of transplant rejection is endothelial rejection, which accounts for about 50% of corneal transplants, and eventually, mixed rejection occurs in 30% of transplants.

How to manage and treat cornea transplantation?

Transplant rejection is one of the most difficult complications after corneal transplant surgery, the management, and reversibility of which depends on the damaged layer of the cornea. The important point is that you should avoid corneal transplants for eyes that are actively inflamed as much as possible. Because if you do a corneal transplant when the eyes are actively inflamed, corneal rejection is more likely. Topical steroid therapies are used for high-risk recipients as primary treatment for transplant rejection and preventive treatment after corneal transplantation. Topical corticosteroids are recommended for the treatment of epithelial and sub-epithelial cornea rejections with higher reversibility rates, which should be used at a reduced dose of 6 times a day for 6 to 8 weeks. It should be noted that long-term use of corticosteroids will lead to many side effects such as cataracts, glaucoma, immunosuppression, and impaired wound healing. Hence, alternative therapies are being evaluated.

Factors Increasing The Risk of Corneal Transplant Rejection

Many factors can increase the risk of cornea rejection, including:

• Young age of transplant recipients
• Gender mismatch between recipient and donor
• Transplant with large diameter or outside the center of the cornea
• Loose or open stitches
• Previous transplant in the same eye and reject the previous transplant
• Iris adhesion with the transplanted cornea
• Bacterial or other infections
• Inflammatory diseases such as anterior uveitis
• Glaucoma
• Reduction of steroid therapy
• Preforming subsequent eye surgeries, such as cataracts
• Lack of tears
• Trauma

Diseases that can be treated with cornea transplantation include:

• Corneal hump (a cornea with a large protrusion)
• Fuchs dystrophy (an inherited eye disease)
• Thinning or rupture of the cornea
• Corneal ulcers (caused by infection or damage to the cornea)
• Corneal swelling
• Complications of previous eye surgery
• When corneal ulcers have not been treated with medication.

Corneal transplantation is often suitable for restoring the eyesight of people with corneal injuries. Corneal transplantation can relieve pain or other symptoms associated with corneal diseases.

Results of Corneal Transplantation in Iran

The visual acuity of most people who receive corneal transplant surgery in Iran improves greatly. But your expectations of a corneal transplant outcome depend on your overall health and your aims for surgery. However, corneal transplantation is a low-risk surgery. But the risk of possible complications persists for years after corneal transplant surgery. For this reason, after a corneal transplant, you should visit an ophthalmologist annually to check the condition of the corneal transplant and prevent any possible complications.

Vision Correction After Corneal Transplantation

After corneal transplant surgery, vision is likely to deteriorate. Because it may take several months for the eye to adapt to the new cornea. When the outer layer of the cornea improves, the ophthalmologist can improve your eyesight by some making modifications, such as:

1.Correction of corneal roughness

When corneal sutures have a dent or bulge, the vision may become blurry. Your doctor will fix this problem and restore your vision by loosening some stitches and tightening others.

2.Correction of visual disorders

If a person has refractive defects such as myopia and farsightedness, your doctor will correct these disorders by prescribing glasses or contact lenses. In some cases, correcting these defects with laser-assisted surgeries will be more effective than glasses and lenses.

Corneal Transplantation Preoperative Tests:

Before corneal transplant surgery in Iran, the following tests are required:

• Full eye examination

 Before corneal transplant surgery in Iran, the doctor thoroughly examines the eyes to identify the factors that cause complications or rejection of the cornea.

• Measuring the eyes

 Measuring the eyes determines the size of the donated cornea, so the doctor will cut the cornea to the size of your eye.

• Treatment of other eye problems before transplantation

 Eye problems and diseases such as infection or inflammation reduce the success rate of corneal transplantation and cause corneal rejection. Therefore, any eye diseases should be treated before corneal transplantation to minimize the risk of rejection.

Cornea Transplantation in Iran

Iran is one of the most advanced countries in providing medical services to international patients. By equipping its hospitals as well as the presence of experienced and skilled eye surgeons, Iran has become an ideal destination for various eye surgeries, including corneal transplant surgery. In terms of economic efficiency, Iran is one of the best countries for various surgeries. You can pay less for corneal transplant surgery by traveling to Iran. Also, with skilled and experienced surgeons and up-to-date and advanced facilities in Iran, you can safely choose Iran as a suitable destination for corneal transplantation surgery.

Concluding Remarks

Corneal rejection is the most common cause of corneal transplant failure. Transplant recipients who receive a corneal transplant for the first time benefit about 90% from the survival of the transplant for two years. While this rate is reduced to 35% to 70% for high-risk recipients. In one-third of all failed corneal transplants, symptoms of a malignant attack have been identified by the immune system. Therefore, it is necessary to investigate the factors that may lead to the rejection and failure of corneal transplantation. If these symptoms are identified before the corneal transplant, the doctor can decide whether a corneal transplant is a good option for the patient. Once a corneal transplant has been successfully done, events such as a transplant wound or coronary artery stenosis that may occur after the transplant should be avoided. Transplant rejection usually occurs 6 months after receiving a corneal transplant, and more than 10% of transplant complications occur up to four years after surgery. Therefore, all transplants need long-term management and care because they are indefinitely at risk. To get the necessary instructions about corneal transplantation surgery in Iran, please contact the expert counselors of Moj Aramesh Amitis Health Tourism Company.

Author: Sh. Khazaei

Translator: N. Rahimifar