ummit Technologies developed the first excimer laser that could be used for surgery. A year after, the Food and Drug Administration (FDA) approved this excimer laser and stated that it could only be used to correct mild nearsightedness in a procedure called Photorefractive Keratectomy (PK). In PRK, surgeons scrape away the very outer layer of the cornea (less than 5% thickness of the entire cornea) and then use the excimer laser to vaporize the underlying corneal tissue to a predetermined depth (no more than fifty percent thickness of the cornea). These results were very good as 90 percent of the cases showed that the patients achieved at least 20/40 vision, which is the usual standard to pass a drivers license test; however, the surgery had many drawbacks. While the procedure itself was not painful, patients had significant pain and discomfort for almost a week after the surgery (Gallo, 129). Worst of all, it often took a week to even see anything and six months to get the full benefits of the surgery (Gallo, 129). Dr. Stephen Slade, a refractive surgeon, summarized the procedure well by saying, PRK works well, but it hurts and the results take too long. To be honest, patients dont like it. Soon after PRK was introduced, surgeons began testing a procedure called Laser In-Situ Keratomileusis, which was first partially introduced by the father of ophthalmology, Barraquer in 1950 (Slade, 8). Keratomileusis is derived from the Greek root keras (horn-like cornea) and mileusis (carving) and basically it is a procedure that involves slicing and peeling back the outer layer of the cornea (anterior cornea), leaving a hinge on one side, while the laser sculpts the tissue underneath (corneal stroma). After the excimer laser is done, the flap is placed back to where it was before, and no stitches are needed because the corneal flap heals by itself when left to dry. You are probably wondering if they still used the diamond scalpel, and ...
