Evolution of corneal refractive surgery: From RK to LASIK
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A cover story on LASIK brings back a lot of memories for me.
I engaged in corneal refractive surgery in a significant way when I agreed in 1980 to serve as a surgeon in the Prospective Evaluation of Radial Keratotomy (PERK) study led by the late George O. Waring III, MD. It became immediately apparent when recruiting patients for this study that there was significant demand for a surgical alternative to treat myopia and astigmatism. Radial keratotomy (RK) and its close cousin astigmatic keratotomy (AK) became far more popular with patients than I expected despite being invasive and marginally accurate and generating an unstable refractive outcome for many patients. We early incisional corneal refractive surgeons learned to reduce the range of myopia and astigmatism targeted and the invasive nature of the surgery by limiting the number, reducing the length and enlarging the central clear optical zone of our incisions (mini-RK and AK).
While patient satisfaction was high and patient demand was strong, it was clear to me that we needed a better corneal refractive surgery procedure. The disruptive innovation waiting to be applied to our field was the excimer laser. In 1981, around the start date of the PERK study, a group of brilliant scientists at the IBM Watson Research Center led by Rangaswamy Srinivasan, PhD, discovered that they could ablate human tissue with sub-micron accuracy with an excimer laser. I constantly teach that “fortune favors the prepared mind” (Louis Pasteur), and in the case of the excimer laser, the prepared mind was the ophthalmologist Stephen Trokel, MD, at Columbia University. He traveled to the IBM Watson Center, engaged with Srinivasan, and performed the first research on human corneal tissue starting with excimer laser RK and evolving to excimer laser surface ablation in 1983. He rapidly realized the potential for the excimer laser to revolutionize corneal refractive surgery and wisely applied for the seminal patents in the field and founded a company, Visx USA, along with Charles Munnerlyn, PhD, and Terry Clapham to develop the technology. Other companies were soon founded, including Summit and Taunton, which later merged with Visx.
Another brilliant, prepared mind, Marguerite McDonald, MD, visited Dr. Trokel and became an early proponent of excimer laser corneal refractive surgery. She led groundbreaking research at LSU and performed the first excimer laser surface ablation on a volunteer patient scheduled for enucleation for an ocular tumor in 1988. The results exceeded expectations, attracting human and financial capital, and a major new vertical in ophthalmology, laser corneal refractive surgery, was born.
In 1995, the Summit excimer laser achieved FDA approval for the treatment of myopia with surface ablation, and in 1996, the Visx laser was approved. At the same time, automated corneal microkeratomes were being developed to support automated lamellar keratoplasty for the treatment of myopia outside the range of RK. Many prepared minds around the world rapidly appreciated that the microkeratome could be combined with the excimer laser to allow corneal tissue to be removed in the stroma, and LASIK was born, allowing more rapid and less painful visual recovery.
The transition from surface ablation to LASIK was rapid and global and preceded FDA approval, which was first achieved by Summit and Visx 2 years later in 1999. LASIK procedure volumes grew rapidly worldwide, and in 2001, just more than 1.4 million procedures were performed in the United States alone. Many expected procedure volumes to grow to at least 3 million per year, but the Sept. 11 attacks resulted in a recession with loss of consumer confidence and a significant decline in LASIK cases performed.
Despite continuous incremental improvements in the efficacy, safety and patient satisfaction associated with LASIK, along with the presence of more potential patients as the prevalence of myopia has grown, we today perform only half as many procedures as we did 2 decades ago. The reasons are multifactorial, widely debated and, in my opinion, unexpected.
According to data on the FDA website, there have been 10 more FDA approvals for LASIK since Summit and Visx in 1999, bringing Bausch + Lomb, Nidek, Alcon and Zeiss into the U.S. market. Johnson & Johnson Vision now owns Visx, and Summit has disappeared from the market.
The femtosecond laser was first applied to LASIK flap creation by IntraLase, enhancing LASIK safety, and achieved FDA approval in 2001. More recently, a new femtosecond laser approach to corneal refractive surgery, small incision lenticule extraction, was pioneered by Zeiss, achieving FDA approval in 2016. In 2023, Johnson & Johnson Vision joined this effort with its Elita femtosecond laser system.
Nearly 10 million patients in the U.S. and more than 30 million in the world have benefited from laser corneal refractive surgery. The development and adoption of laser corneal refractive surgery is a perfect example of the innovation cycle at work and confirms the critical role ophthalmologists play in advancing the art and science of our field. While I have mentioned only a few colleagues in this commentary, the current state of the art in laser corneal refractive surgery was created by the efforts of thousands of ophthalmologists, scientists and industry members working together.
Every day, we ophthalmologists strive to preserve and restore vision. With laser corneal refractive surgery, we not only restore but often enhance vision to a higher level, improving our patients’ quality of life. Laser refractive corneal surgery and lens-based refractive surgery are two modern-day miracles. Both were unexpected and disruptive, created lucrative verticals with new company leaders, and have been extraordinarily positive for patients, surgeons and industry.
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