EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
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EW NEWS & OPINION January 2016 15 again in 2007. With the great reces- sion, LASIK volume fell dramatically to less than 700,000 cases a year and has not rebounded with the return of consumer confidence. There are many theories re- garding the 50% reduction in LASIK volume over the last 8 years, but undoubtedly unfounded patient fear remains a significant concern for many prospective patients. Many of these trepidations are not based on fact but are potentiated by misinfor- mation. The early LASIK cases of the 1990s had excellent results but have been overwhelmingly improved by better technology, surgical techniques, diagnostic equipment, and patient selection. In the 1990s patients were treated with up to 25 diopters of myopia, preexisting dry eye disease, and irregular corneas. Eliminating poor candidates has been an enormous help in improv- ing refractive outcomes and patient satisfaction. The major reason for the mark- edly improved outcomes of LASIK today, however, is the collaboration between ophthalmologists and in- dustry to identify unmet needs and reduce or resolve complications with better technology. Early excimer laser treatments had significantly greater risk of loss of BCVA due to decentered ablation zones. Cen- tration of the excimer laser was performed manually and patient movement could not be compen- sated. Today we have pupil trackers that correct for patient movement and when the patient moves signifi- cantly will automatically turn off the laser treatment. Newer inno- vations including pupil centroid shift and cyclotorsion management have further improved excimer laser delivery. PRK originally had a major concern of corneal scarring. The rou- tine use of mitomycin-C and better epithelial management has largely eliminated this problem. The most common significant complication in the early days of LASIK was flap formation. Early mi- crokeratomes had unpredictable flap thicknesses and a higher incidence of a variety of flap complications including incomplete, decentered, I n spite of LASIK's long clinical and historical presence, mis- conceptions regarding the risks and benefits of this proce- dure persist, eroding both the reputation of the procedure and of those in the field with unwavering support. The history of LASIK is one of the most interesting stories of this generation. The excimer laser was invented by Rangaswamy Srinivsasan, an IBM researcher, in 1982 for the purpose of etching silicone microchips. The credit for bringing the excimer laser to ophthalmology goes to Stephen Trokel, who performed the first animal experiments in 1985. Com- mercial development began in 1988 with Summit and VISX performing FDA trials. While the excimer laser was invented in the United States, the first commercial cases were performed internationally in Europe and Canada. The early lasers had small oblate ablation zones without peripheral blend zones and had a high incidence of glare and halos. However, they were dramatically better than the previous state of the art, radial keratotomy. The excimer laser was finally approved in the United States in 1995. The early studies of PRK had a high incidence of loss of 2 lines of best corrected visual acuity of approximately 5%, and 20/20 vision was achieved in 80% of patients. LASIK quickly supplanted PRK as the dominant refractive procedure, and the refractive volume in the United States and Europe exploded, peaking at 1.4 million procedures a year in 2000, declining after 9/11 with the loss of consumer confidence but quickly rebounding to 1.4 million by Eric Donnenfeld, MD, EyeWorld chief medical editor Can LASIK be saved? Nasal & Temporal Speculums 3360 Scherer Drive, Suite B, St. Petersburg, FL 33716 800-637-4346 • Tel: 727-209-2244 • Fax: 727-341-8123 Email: Info@RheinMedical.com • Website: www.RheinMedical.com *Developed In Coordination with Reay H. Brown, M.D. ** Developed In Coordination With Roger F. Steinert, M.D. Leonardo Da Vinci, Unnamed ADBC 1339 Rev.A Call 727-209-2244 For More Information. Special Fenestrated B l a d e s I m p r o v e Exposure And Access To Superior Surgical Approaches By Supporting & Elevating The Middle Of The Lids As Seen In The Following: Figure 1, Temporal Blades With Drape. Figure 2, Temporal Blades Without Drape. F i gu r e 2 F i g u r e 1 08 -08164 : Brow n* T ri p le Post Specul um , Stai nless 05 -7105 : Br o wn* T ri ple P ost S peculum, T ita niu m 08-08164 -S: St eine rt * *-B rown* Triple Post Specul u m , Nasal, S tainless 05-7105-T: Steinert**-Brow n * Triple Post Speculum , Nasa l, T itani u m VIDEO continued on page 16 Eric Donnenfeld, MD Chief medical editor's corner of the world