Cornea graft

Do you suffer from a pathology of the cornea ? You’ve come to the right place !

Many diseases of the cornea can be treated by doing a corneal transplant, or ‘graft’. The most common indications are a loss of transparency from scarring or perhaps edema, or corneal distortion; usually keratoconus.

When the techniques are well mastered, the post-operative follow-up is simple: post-operative treatment is local, in the form of eye drops and is not restrictive.

The graft is either a ‘penetrating keratoplasty’ graft, often called ‘P.K’ or it is an ‘posterior lamellar keratoplasty’, known as ‘P.L.K’. The choice of the type of graft depends on the location of the problem. Lamellar grafts have the advantage of being more respectful to the normal ocular structure; therefore visual recovery is normally faster.

 

 

Penetrating Keratoplasty

Endothelial corneal graft (or posterior lamellar keratoplasty - P.L.K)

Endothelial corneal transplantations can treat damage to the corneal endothelium. The endothelium is a thin unicellular layer that lines the inner surface of the cornea. Its job is to regulate the amount of aqueous humor (eye fluid) in the eye that infiltrates naturally into the cornea.

Endothelial cells may become less numerous due to:
1/ Pathologies: the most well-known is ‘cornea guttata’ also known as Fuchs dystrophy.
2/ Trauma; most often surgical: e.g. difficult cataract surgery or certain intraocular lenses placed against the inner surface of the cornea used to correct myopia.

Endothelial cells can not regenerate. When their number is too low, the endothelial pump function becomes insufficient, which means that the amount of fluid contained in the thickness of the cornea becomes too large. This is called corneal edema. The cornea loses its transparency meaning that the vision is then altered.

Previously, corneal edema was treated by a penetrating transplant (total graft) which consisted of replacing the entire thickness of the cornea. This technique required a 360° incision of the cornea. The current surgical technique - endothelial grafting - allows the surgeon to replace only the diseased part of the cornea: the endothelial layer.

The advantages of this partial graft are mainly related to the reduced size of the incision:

  • Eye trauma is limited
  • Induced astigmatism is weak
  • No stitches needed
  • Local anesthesia is possible

Visual recovery lasts about one month versus up to one year with a total graft. Average recovery quality is 12/20 but can reach 20/20.

After surgery it is necessary to wear glasses to correct the induced astigmatism, of which the severity is generally low, contrary to the correction required after a total graft which can induce an astigmatism of generally four to five diopters.

The procedure :

The operation is carried out as an outpatient procedure in the same way as for a cataract operation. You enter the clinic on the morning of the operation and you can return to your home the same evening.

Anesthesia is usually local. The procedure lasts about 20 minutes. It consists of :

  • Grafting of healthy endothelial cells
  • Removing the diseased endothelial layer by a small incision
  • Inserting a ‘lamella’ -a thin layer of cells- carrying healthy endothelial cells through the incision
  • Keeping this lamellae placed on the inner face of the cornea thanks to an injection of an air bubble which evacuates itself in a few hours
 
POST OPERATION

The surgical processes are generally almost painless. A feeling of "grains of sand" is common during the first few hours. Headaches are possible.

The post-operative treatment is local (eye drops) and it lasts for 9 months. The objective is to prevent post-operative infection and reduce the risk of rejection.

During the week following the operation, you must:

  • Avoid dusty environments
  • Do not rub your eye
  • Disinfect your hands often with a hydro-alcoholic gel, especially when instilling eye drops

Your post-operative follow-up will consist of several check-up visits: the day after the operation, 8 days after, 1 month after, 3 months after, 1 year after, and then every year.

 

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