Role of a healthy cornea: The cornea is a transparent tissue that forms the front part of the eye. The light that hits your eye first passes through the cornea, through the pupil (the dark spot in the centre of the iris), and then form images on the retina.
The cornea must obviously keep clear to allow you to see properly. However, there are a number of diseases that can damage the cornea and consequently impair your sight. These pathological events include:
- Corneal scars caused by traumas and infections.
- Keratoconus. A degenerative condition in which the cornea becomes thin and deforms.
- Inherited corneal conditions (dystrophies) such as Fuchs’ dystrophy and others.
Types of Corneal Transplants
The cornea is composed of five layers. Corneal transplants do not always involve all such layers.
Perforating (full-thickness) keratoplasty.
This involves transplanting all the donor’s corneal layers.
During this procedure, the surgeon only replaces some of the layers of the cornea involved in the transplant.
In a lamellar corneal transplant, only a few selected layers are transplanted; this can concern the deepest layer, called endothelium (in which case we speak of posterior lamellar corneal transplant). The most commonly performed versions of this procedure are Descemet Strip Automated Endothelial Keratoplasty (DSAEK) and Descemet Membrane Endothelial Keratoplasty (DMEK).
In other cases, it can include instead layers closer to the surface (in which case we speak of anterior lamellar corneal transplant).
At Centro Vista we perform any type of corneal transplant, whether perforating or lamellar. We have had for years an agreement with the Eye Bank of Veneto and provide these services as part of the outpatient care system, so without hospitalization, with interventions lasting no more than one hour from the time of admittance to the time of discharge. It should be well kept in mind that in our operating room the anaesthetist is always present. For any assistance that may become necessary before, during and after surgery.
Stem cell transplant
Limbar Stem Cell Deficiency (LSCD)
Corneal transparency is essential to ensure the ability to see correctly. Corneal cell renewal and its repair depend on the cells present in the limbus, which is located in a small area of the eye between the cornea and conjunctiva. Thermal or chemical burns may destroy the limbus, causing a deficiency of limbal cells. If this happens, the cornea loses its natural transparency and is covered by an epithelium other than its normal one, following the invasion of cells from the conjunctiva. This process makes the cornea opaque and consequently causes the loss of vision. In such cases, conventional corneal transplant is an ineffective treatment, as it specifically designed for clouding.
The therapy is based on cultures of cells of the limbus taken from the patient which, once successfully engrafted, regenerate the corneal epithelium and restore its functions. The limbal cell cultures also allow the treatment of patients with a loss of the corneal epithelium in both eyes, as long as a small portion of the limbus has remained in one of the eyes
Amniotic membrane implant
In fact it is not a real transplant, but a procedure which involves, in particular cases, covering the affected surface of the cornea with a thin membrane, which has in turn been previously taken from the amniotic sac, the membranes coating the foetus in pregnant women. The eye bank deals with the collection and preparation of these membranes, rich in valuable components for the corneal surface, so that it can be implanted for a short period in selected cases.
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