Keratoconus – Treatment – Cornea Transplants
Corneal transplants are a last resort in keratoconus treatment. Transplants have a high success rate (92-95% for people between 20-35 years of age). During this procedure, the central part of the patient’s cornea is replaced with a transplant from a healthy donor. If the full-thickness of the central part of the cornea is replaced, the procedure is called penetrating keratoplasty, while if only a layer of the damaged cornea is replaced, the procedure is called partial-thickness (lamellar) keratoplasty.
What is the probability of a transplant rejection and what is the recommended post-operative treatment?
Corneal transplants are rather rarely rejected and in keratoconous cases the rejection rate is under 5%. The reason for this is that tissue transplants lack vessels and are sutured on avascular tissue. Therefore, in usual corneal transplants there is no histocompatibility testing and the blood type of the donor and the recipient do not need to be checked. The post-operative treatment includes eye drops that are instilled to the eye every few hours for the first days and treatment lasts 3-4 months. Only a few, special cases require the use of a special preoperative or postoperative treatment.
What other possible complications are there except transplant rejection?
Complications of keratomileusis (apart transplant rejection) are like any other intraocular surgery, such as cataract. These include infection, inflammation, increase of ocular pressure, as well as complications in the posterior segment of the eye such as expulsive bleeding and retinal detachment. These are extremely rare and even if they do occur, are treatable most of the time. Due to the technique of partial-thickness keratoplasty, which includes only the ocular surface (extraocular surgery), the above complications do not occur.
Apart from the above mentioned, post-operative astigmatism may occur. More specifically, in keratoconus transplants, post-operative astigmatism is likely and occurs with an average of 3.5D.
When can a patient return to everyday activities following a keratoplasty?
The patient returns home on the day of the surgery and the protective dressing is removed the following day. Although visual acuity will be gradually improving over the following months, the patient does not need to remain abed after the surgery. Depending both on the patient’s preoperative vision and on the vision of their other eye, the patient can return immediately to work if they are using the required protective glasses.