The cornea is the gateway for external images into the eye. It is a transparent tissue that forms the front part of the eye (Figure 1).

 It is a highly specialized tissue that refracts and transmits light to the lens and retina. If this tissue is diseased or injured, it may turn cloudy or opaque and prevent light from entering into the eye. It may be so severely damaged that it perforates and may lead to losing of the entire eyeball and blindness.

The objectives of corneal transplantation, depending on the corneal pathology present, may include one or more of the following:

(1) establish a clear central cornea/visual axis (Figure 3),

 (2) minimize refractive error (Figure 4),

 (3) provide structural support (Figure 5),

 (4) alleviate pain (Figure 6),

 and (5) eliminate infection (Figure 7).

Corneal transplantation is one of the most successful types of organ transplantation and is the most frequently performed transplant procedure in this country. In Malaysia, corneal transplantation began in the 70s. The first corneal transplantation was performed in Hospital Kuala Lumpur. In the year 2004, more than 170 cases of corneal transplantation were performed in Malaysia. Patients with corneal diseases no longer need to seek expensive treatment overseas. Most of the different types of corneal transplantation can be performed in Malaysia at a fraction of the cost if done overseas.

Advancements in microsurgical techniques, eye banking as well as early recognition and effective treatment of graft rejection have led to very high success rates in achieving and maintaining optical clarity in corneal graft.

There are cases of corneal problems that only affect the front part of the tissue, these include corneal scarring from previous infection, keratoconus, opaque cornea from dystrophies or abnormally shaped cornea after laser refractive surgery. These are some of the cases that can undergo partial thickness corneal transplantation that  is called deep lamellar keratoplasty (Please refer to article on Deep Lamellar Keratoplasty). This procedure involves the transplantation of non-viable donor corneal tissue and preserves the recipient’s corneal endothelial cells. This procedure virtually eliminates the risk of graft rejection and simplifies post-op management.

Previously, the single most common obstacle for a patient to undergo corneal transplantation is difficulty in getting donor corneal tissue. This issue is largely resolved due to the availability of imported corneal tissue.

Local eye donors are still scarce despite all the efforts in promoting organ and tissue donation. 

Unlike other organs, the cornea is still viable for transplantation even hours after death. The eye can still be harvested up to a maximum of 12 hours after death. However, as a rule, the shorter the interval, the better the quality of the tissue acquired. The harvested eye can be either stored in a moist chamber at 4 ⁰ C (Figure 10) for a maximum period of 48 hours or as corneal-scleral rim in storage medium for a maximum period of 14 days (Figure 11).

Usually the whole eye is removed during procurement, however, if the donor only wishes to donate the cornea and not the whole eye, then only the corneal-scleral rim is removed. The procurement can be performed in the hospital ward, mortuary or even the donor’s house. Tissue can be harvested from donors between the ages of two years old up to the age of 90 years.

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