A corneal transplant, or keratoplasty, replaces diseased or damaged corneal tissue with healthy donor tissue to restore vision. The cornea is the clear, dome-shaped outer layer of the eye, and its clarity is paramount for proper focusing of light. Although the cornea is considered an “immune-privileged” site, the most common reason for late-stage graft failure is rejection. This rejection occurs when the recipient’s immune system identifies the donor tissue as foreign and mounts an attack. Treatment aims to suppress this immune response before it causes irreversible damage to the transplanted tissue.
Recognizing the Signs of Rejection
Corneal transplant rejection signs are noticeable to the patient. A helpful way to remember the symptoms that require immediate attention is the acronym RSVP. The “R” stands for Redness or injection of the eye, and the “S” represents Sensitivity to light (photophobia). The “V” signifies a decrease in Vision, often described as a cloudy or foggy sensation. The “P” stands for Pain, irritation, or discomfort that is not otherwise explained.
These symptoms indicate that the immune system’s white blood cells are migrating to the graft and beginning their destructive process. The most serious form of rejection involves the endothelium, the single layer of cells responsible for keeping the cornea clear by pumping out fluid.
The Urgency of Intervention
Corneal transplant rejection can be reversed, but prompt intervention is crucial. Successful reversal rates range from 50% to over 90% when treatment is initiated quickly. The immune attack must be halted rapidly because the donor endothelial cells, which maintain corneal clarity, do not naturally regenerate.
If the immune response continues, the loss of endothelial cells causes the cornea to swell and become permanently cloudy, leading to irreversible graft failure. Delaying treatment by even a single day significantly increases the risk of permanent cell loss. Therefore, a patient experiencing any RSVP symptoms must contact their eye specialist immediately.
Standard Medical Interventions
The primary strategy for reversing an acute rejection episode is intensive, high-dose immunosuppression. Topical steroid drops, such as prednisolone acetate or dexamethasone, are the mainstay of treatment because they penetrate the anterior chamber effectively. For severe endothelial rejection, the regimen is aggressive, often involving application as frequently as every hour while the patient is awake for the first few days.
In cases of severe or high-risk rejection, treatment may escalate to include systemic corticosteroids. This can involve a high-dose oral steroid, such as 60 to 80 milligrams of prednisone daily, which is gradually tapered down over several weeks. Some specialists may opt for an intravenous “pulse” of a drug like methylprednisolone, which rapidly reduces circulating immune cells and improves the likelihood of reversal.
Long-Term Outcomes After Reversal
Following a successful reversal of an acute rejection episode, the graft may become clinically indistinguishable from its state before the event. However, reversal does not eliminate the long-term risk of recurrence or future graft failure. Patients who have experienced rejection typically require a prolonged course of maintenance immunosuppression, often a lower-dose topical steroid, to prevent a subsequent attack.
This long-term medication use requires careful monitoring due to the potential side effects associated with corticosteroids. Risks include a rise in intraocular pressure, which can lead to secondary glaucoma, and the acceleration of cataract formation. Adherence to the medication schedule and regular monitoring by an ophthalmologist are necessary to maintain graft clarity and mitigate these complications.