A corneal transplant, also known as corneal grafting or keratoplasty, is an operation that replaces the opaque cornea with a clear cornea obtained from a human donor.
Corneal grafting improves visual acuity, preserves or reconstructs the anatomy of the eye, removes tissues unresponsive to treatment and provides cosmetic improvements to patients with corneal scars.
History of corneal Transplants
The first cornea transplant was performed by Dr. Eduard Konrad Zirm of Austria, on 7 December, 1905. The surgery that he performed was also the first successful human tissue transplant .
Two of the other prominent pioneers of keratoplasty are Dr. Ramon Castroviejo Briones from Spain and Dr. Vladimir Filatov from Russia.
For centuries before Zirm’s stupendous accomplishment, the idea of replacing an opaque cornea with a good one had been in circulation. It was the attendant advances in the fields of anaesthesia and antisepsis during this time that finally tilted the balance to make the surgery possible. However, even after this first one, there was a wait of several decades, when the procedure was fine tuned, before keratoplasty became common.
In the latter half of the 20th century, the pioneering doctors and scientists were able to cross several milestones in technique and instrumentation, including the use of better microscopes and sutures that were finer than human hair. This was the tipping point. Keratoplasty finally became a procedure that could be carried out with the expectation of a successful graft and improved vision. Since then, more than a million people around the world have had their eyesight restored through corneal transplants, the most successful of all transplants.
Alternatives for Corneal Grafting
Thousands all over the world have benefitted from the wonderful surgery of corneal grafting. However, it is not the last word in restoring sight to the many corneal blinds living in a world of darkness.
The technique of Phototherapeutic Keratectomy (PTK) provides an alternative to the long wait for a donor eye that can go on for years or even a life-time. This surgery involves using a computer-controlled, precise laser to excise tissue from the cornea, in order to remove superficial irregularities and surface opacities associated with many dystrophies and scars.
Since thin layers of the diseased tissue are microscopically vaporized by the laser, there is very little trauma to the area surrounding the site of treatment. New tissue grows over the surface that has been smoothened and cleansed by surgery.
Unlike in a corneal transplant, recovery for PTK takes only days, instead of months. The return of vision can occur rapidly, especially if treatment has been confined to the top layer. Studies show a success rate of 85 percent for PTK.
PTK ensures minimal tissue removal and surgical treatment and is therefore, a much better option than the mechanical keratectomy that was used before.