This three-part overview takes a look at where LASIK has been, where it is and where it is going.
It has been more than 20 years since the FDA approved LASIK, with now over 10 million Americans having undergone the procedure experiencing life-changing results. In this first part of the series, I review where the procedure has been and where it may be headed.
What was: RK, PRK, PTK
In the days before LASIK, refractive surgery was performed via radial keratotomy (RK), today a largely obsolete procedure. In the late 1970s, the “cutting” edge of surgery entailed slicing into the corneal surface, using several incisions to reshape the eye’s curvature and thereby correct refractive error. It was the primary procedure for treating patients with –1.00 D to –4.00 D of myopia, and patients could expect to become less dependent on glasses as a result.
To produce more accurate RK incisions, eventually the excimer laser was used instead of a scalpel. Did excimer lasers do RK? I was not aware? No tissue was removed from the central cornea like today’s LASIK procedures; the hinged flap technique still used today was developed in the late 1980s. IBM researchers originally devised the excimer laser to mark computer chips for theft control. It was found to be especially helpful for precisely removing tissue, a method that proved to be considerably safer and more effective than RK.
In 1983, Stephen Trokel, MD, published the first paper on the potential of PRK in humans. He filed a patent for PRK later that year that was issued in 1990. Francis L’Esperance, MD, also filed a patent that was subsequently issued in 1987. The founding of Taunton Technology, VisX and Summit Technology Inc. soon followed.
In 1985, Theo Seiler, MD, PhD, performed the first excimer laser phototherapeutic keratectomy (PTK) in a sighted eye, in Germany. Two years later, L’Esperance did the first U.S. PRK on a nonsighted eye, and soon the first FDA trial began. He also performed the first PRK on a sighted eye that year. Marguerite McDonald, MD, become the first surgeon to achieve successful refraction with PRK on a normally sighted myope 3 years later.
FDA gets on board
In 1994, the FDA’s Ophthalmic Devices Panel recommended approval of Summit’s excimer laser for PTK, followed by an OK for the VisX platform. Next, the panel recommended approval — with conditions — for PRK with the Summit laser. Premarket approval was granted in 1995 for PTK using both Summit and VisX lasers. FDA then approved the Summit laser for PRK and issued an approvable letter to VisX for PRK.