Improving Eyesight Cornea Transplants - Safe and Fast Techniques

Corneal transplant is performed to enhance the appearance of the diseased or damaged cornea, to reduce pain and to restore vision. A clear, healthy cornea is essential for good vision; any damage caused can severely misshapen, scar or distort the vision. If the contact lenses or eyeglasses cannot restore the functional vision or the painful swelling does not go away, a cornea transplant may be necessary.  It is usually a safe process and is mostly successful, however, there is still a small risk involved like the rejection of the donor cornea.

When the clarity of the cornea gets affected by certain conditions and there exists a greater risk of corneal failure, Cornea transplant is required. A variety of conditions can be treated with corneal transplants, some of them are-

A sedative is given to relax, while the local anesthesia is used to numb the eye. The penetrating keratoplasty is most common, in which the surgeon removes the button-sized disc of the corneal tissue by cutting through the thickness of the diseased or abnormal cornea. The trephine instrument is used to a precise circular cut. The donor cornea is then placed in the opening after cutting it to fit. The new cornea is stitched into place with a fine thread, which may be removed at a later visit. In case a person is not eligible for a cornea transplant from a donor cornea, an artificial cornea is inserted.

Since there are some types of cornea problems, a full thickness cornea transplant is not always an appropriate treatment. There are procedures that involve removal of the only certain layer of corneal tissue or just the tissue affected by the disease.

 

Endothelial keratoplasty (EK) - this procedure involves the removal of diseased tissue from the back corneal layers. The endothelium is also removed along with the thin layer of tissue protecting the endothelium from infection and injury called as Descemet membrane. The donor tissue is implanted with utmost care so as to replace the removed tissue.

The two types of endothelial keratoplasty are -

1. Descemet stripping endothelial keratoplasty (DSEK) which utilizes donor tissue to replace just one-third of the cornea.

 

2. Descemet membrane endothelial keratoplasty (DMEK) is a new procedure which utilizes thinner layers of donor tissue. This procedure is not commonly used and is more challenging since the tissue used is very thin and fragile.

Anterior lamellar keratoplasty (ALK)- this process involves the removal of diseased tissue from the front corneal layers, which includes the stroma as well as epithelium. However, the endothelial layer is left untouched. The type of ALK procedure is determined by the depth of corneal damage.

1. Superficial anterior lamellar keratoplasty (SALK) replaces just the front layers of the cornea, while the healthy endothelium remains intact.

2. Deep anterior lamellar transplant (DALK) is performed when the cornea damage extends deep inside the stroma. Usually, a small incision is made in the side of the eyeball and the front and middle layers of the cornea are removed without damaging the back. The healthy donor tissue is then grafted so that it replaces the removed portion.

Human donor tissue is most successful and preferred option to replace an injured or diseased cornea. But there are instances where patients are at a higher risk of corneal transplant failure (like multiple failed human cornea transplants). When no option remains to help the vision, artificial tissue can be used. The biosynthetic cornea is safe and is developed from synthetically cross-linked recombinant human collagen. The cells and the nerves grow into the implant, resulting in the regenerated cornea, which is just like healthy, normal tissue.