When the cornea irreversibly loses its transparency or become highly irregular, or likely to be punctured and less invasive treatments do not solve the problem, it must be replaced through corneal transplant surgery, also called keratoplasty.

What are corneal transplants?

The intervention consists of the replacement of diseased cornea or a part of the cornea with healthy cornea from a donor. Unlike the recent past, when the only intervention available consisted of the replacement of full-thickness tissue, now one can decide to replace only part of the diseased tissue, leaving the remaining layers of the cornea intact. This has reduced the aggressiveness of the surgery, the risks of rejection and accelerates the functional recovery. Depending on the damage of the corneal layer (stroma, endothelium) we can plan a selective transplant of pathological tissue, deep anterior lamellar (DALK – Deep Anterior Lamellar Keratoplasty), in which only the anterior portion of the cornea is replaced, without piercing the eyeball, or a transplant of only corneal endothelium (DSAEK – Descemet Stripping Automated Endothelial Keratoplasty) leaving the most superficial, healthy part intact. 

 

The full-thickness corneal transplantation (PK or keratoplasty) is still open to all cases in which the cornea is damaged, when other treatments were ineffective or when it is determined that the tissue damage will not make the other two techniques effective. In extreme cases, it can only be intended to prevent an impending perforation or as an urgent remedy in order to eliminate the discontinuities between the internal and external ocular structures (transplant purposes tectonic). 

 

The choice of technique is up to the ophthalmologist after a comprehensive evaluation of the clinical condition. The donated corneas are removed from the corpse, carefully selected, preserved in a culture medium and sent to the hospital at its request by BANKS corneas, which certify the quality. This allows one to plan the interventions ahead and ensure a high quality of the tissues to be transplanted. 

 

The transplantation of cornea has the primary purpose of restoring the corneal anatomy and it has the objective to improve the visual function impaired by the reduced transparency and/or other irregularities.

How are corneal transplants performed?

The intervention is planned ahead even if the schedule is dependent on the availability of tissues from the banks of the corneas. The surgery is performed under local or general anaesthesia, depending on the advice of the surgeon and anaesthesiologist. The patient is tested for the absence of contraindications that may require imminent intervention. Following the intervention there is a variable hospital stay of one to three days, the purpose of which is to verify the post-operative course in a safe and protected environment.

What are the advantages and disadvantages of corneal transplants?

There is no surgery without risks. It is therefore not possible to guarantee the success of the intervention or the absence of complications, the incidence of which is also conditioned by the type and degree of evolution of the pathology. The indication for corneal transplant for these reasons must be placed in the absence of medical therapy or less invasive but equally effective treatments.

Is corneal transplantation painful or dangerous?

The surgery is not painful and it is mostly performed under general anaesthesia. Following the intervention, the operated eye is more or less reddened and painful and the patient may feel foreign body sensations, such as burning, discomfort, tearing, fluctuating vision, halos, which then tend to gradually reduce. Since this is a surgery, there are possible complications before, during and after the procedure. There is a high risk of infection, which can be reduced or eliminated by good personal hygiene.

 

The corneal transplant involves a risk of rejection. This phenomenon, whose frequency is significantly reduced after the first 5 years may cause a severe and irreversible eye surface inflammation and in the absence of timely treatment or depending on the severity of its manifestation, it can be an indication for a new cornea transplant.

Which patients can undergo corneal transplants?

Patients of all ages suffering from corneal diseases that do not respond to less invasive therapeutic opportunities and have obtained the consent of anaesthesia for surgery can undergo the procedure.

Follow up

Postoperative controls (initially more frequent) are necessary for a prolonged period of time. If the controls are not carried out according to the requirements, the result of the intervention can be compromised. After surgery there is often a residual astigmatism: in order to reduce that, we have developed a new method of tensioning the suture guided by intraoperative topographic which greatly reduces post-operative astigmatism in the first days after the intervention. 

 

The removal of the suture is performed about a year and a half after the intervention, after which the rearrangement of the cornea can cause the appearance of visual defects such as astigmatism, myopia or hyperopia.

 

 

 

 

The visual improvement is not immediate. It occurs slowly over several weeks and it is linked to the vitality and engraftment of the transplanted cornea, its transparency, the presence of astigmatism residue and the health conditions of the other structures (retina, lens etc.) of the operated eye. The presence of other lesions of the eye, in fact, may limit the recovery of the vision.

Standards of preparation

In preparation for surgery it is necessary to verify the absence of concomitant diseases and/or eye infections and infections in other parts of the body, that may increase the risk of surgery. The patient is required to fast prior to the surgery.