Refractive surgery is surgery to correct the vision in your eyes. There are several different types of refractive surgery including LASIK surgery. LASIK surgery is currently the best known.

 

Radial Keratotomy

In this type of refractive surgery, the shape of the eye is flatten to correct nearsightedness by a series of incisions made in the cornea that resemble the spokes in a bicycle wheel (radial-shaped).

In 1950, Doctor Tsutomu Sato of Japan began performing the first experimental radial keratotomy surgery, however, his results were dismal and his patents often ended up with worsening eyesight.

In the 1970s, a Russian Doctor named Fyodorov began studying the prior efforts made in refractive surgery and became a leading expert in radial keratotomy. Fyodorov was inspired by one of his patients, a young boy with corneal lacerations, the result of an accident with broken eye glasses. Fyodorov observed that the boy had less myopia (nearsightedness) after the injury, a change in the boy's eyesight caused by the cuts in his cornea. Fyodorov worked out the formula for the precise surgical incisions needed to make radial keratotomy have more predictable results.

However, radial keratotomy surgery has its limitations, it is very dependent upon the manual skills of the surgeon. Better methods of refractive surgery were needed, as well as new tools.

 

Introduction of Lasers

During the 1970s, IBM researcher, Doctor Srinivasin realized the potential of the excimer laserto replace a surgeons' knife/scalpel on biological materials. Previously, lasers had been used for industrial purposes, for example, etching computer chips, until Srinivasin introduced lasers to the medical community and that allowed for new medical procedures.

 

Photorefractive Keratectomy

Photorefractive keratectomy is similar to radial keratotomy, however, in photorefractive keratectomy, a laser is used instead of a handheld scalpel to make incisions into the cornea. This type of surgery was first theorized by New York ophthalmologist, Doctor Steven Trokel, who wrote a paper about the potentials of using the excimer laser for eye surgery. In 1983, Stephen Trokel in collaboration with Srinivasan performed the first photorefractive keratectomy surgery in Germany. In 1987, FDA trials began for the excimer laser with a photorefractive keratectomy surgery performed by Marguerite McDonald.

 

LASIK

LASIK is an acronym for Laser Assisted In-situ Keratomileusis. During LASIK surgery a flap is cut into the cornea which is folded back, them the laser corrects the shape of the eye and the flap is then unfolded back over the cornea. Compared to laser-based photorefractive keratectomy described above which uses radial incisions, the surface of the cornea during LASIK remains largely intact so that LASIK patients recover quickly.

Doctor Ioannis Pallikaris was the first person to coin the term LASIK, and was the first surgeon to create a refoldable flap of cornea tissue, rather than removing the entire top layer.

LASIK surgery was first performed in U.S. clinical trials in 1991. While, LASIK is the most recent advancement in laser vision correction, however, we can see that vision correction by surgery does have a long history.

There are currently three major manufacturers of the excimer laser equipment used during LASIK surgery: Summit Technology, Visx and Nidek.

 

Josef Bille - Wavefront-Guided LASIK

Ophthalmology pioneer and University of Heidelberg professor Josef Bille has been instrumental in improving LASIK technology. Josef Bille is the inventor of the WaveScan technology, which is important in customizing LASIK surgery for each patient. Bille was the first person to use the Hartmann-Shack sensor  in ophthalmology. This is a sensor that can determine the optical qualities of an eye based on its shape.

According to Mississippi Custom LASIK , "Wavefront technology was first developed in 1978 by Josef Bille, Ph.D., director of the Institute for Applied Physics at the University of Heidelberg, to measure wavefront distortions that occurred when light traveling through the atmosphere entered a telescopic lens. This technology removed any visual distortion or aberrations from the atmosphere allowing astrophysicists to more accurately view images of the stars and planets.

Ophthalmologists now utilize this technology to record detailed information about the visual characteristics of the eye. Unlike standard measuring devices such as corneal topography, which measure the cornea, or front surface of the eye, the wavefront scans the way the entire optical system processes light."