March 2011

 

NEWS & OPINION

 

ASCRS responds to LASIK critic Morris Waxler


by John Ciccone ASCRS Director of Communications

   

Over the past few months there has been some media coverage of criticisms of LASIK safety and effectiveness by the former U.S. Food and Drug Administration's Center for Devices and Radiological Health (CDRH) chief of ophthalmic devices, Morris Waxler, Ph.D., who was in charge of evaluating LASIK devices approved between 1996 and 2000. In May of last year Dr. Waxler wrote to R. Doyle Stulting, M.D., Ph.D., president of ASCRS, to level his complaints. Dr. Stulting responded in September with a letter, partly quoted below. As members have expressed an interest in ASCRS's response to Dr. Waxler's claims, the salient sections of the letter are provided below.

During my 10 years of service as a member of the FDA's Ophthalmic Devices Committee and three years as its Chairman, I came to know and respect you for your professionalism, knowledge, and dedication during your tenure with the FDA. However, your current view of LASIK is misinformed, unsupported by evidence, and lacking in balance and perspective. In your letter to me, you wrote that the U.S. Food and Drug Administration (FDA), is "complicit" with LASIK manufacturers [manufacturers of ophthalmic excimer lasers], and the American Society of Cataract and Refractive Surgery (ASCRS) is trivializing complications. Nothing could be further from the truth.

LASIK was first approved by the FDA on your watch, following all the required FDA protocols and guidance documents created to measure safety and effectiveness. In fact, laser vision correction is one of the most studied elective surgical procedures, with 7,830 patients representing 16,502 eyes in U.S. FDA clinical trials from 1993 to 2005not to mention more recent submissions to the FDA and thousands of other patients reported in the published literature. The FDA review process is more stringent than that of any other country in the world. Your estimate of the keratectasia rate is inflated and inconsistent with existing data. In your letter you stated, "Keratectasia will occur in over 3,000 patients in 2010 (rate of 0.87 of about 700,000 LASIK surgeries expected to be performed)." Your support for this information is "Ezra Maguen, Yaron S. Rabinowitz, Lee Regev, Mehrnoosh Saghizadeh, Takako Sasaki, and Alexander V. Ljubimov. Alterations of Extracellular Matrix Components and Proteinases in Human Corneal Buttons With INTACS for PostLaser In Situ Keratomileusis Keratectasia and Keratoconus. Cornea. 2008 June; 27(5): 565573." This article (Appendix 2) actually deals with biochemical alterations related to INTACS, does not contain a discussion of keratectasia, and makes no mention of the rate of iatrogenic keratectasia. Thus, it provides no support for the grossly inflated keratectasia rate that you claim in your letter to me.

Elsewhere in your letter, you wrote, "At least 1% of LASIK patients have keratectasia," referencing a report by Pallikaris et al., that actually gives the rate as 0.66% and is the highest estimate in the literature. Since the first report of keratectasia in 19981, the profession has worked diligently to understand this complication and how to avoid itand ASCRS has facilitated this work. Published estimates of its incidence actually range from 0.0004% to 0.66%. The later report is from outside of the United States and is not reflective of the incidence of keratectasia in this country2-3. Another series of papers not referenced by you now allows surgeons to identify and avoid operating on potential patients who are likely to develop ectasia1, 4-5. My colleagues and I even published an editorial to bring these criteria to the attention of LASIK surgeons and make certain that they know how to identify patients at risk for ectasia6. Application of these criteria is now well known and will undoubtedly make the future incidence of ectasia lower than it has been in the past. It is also clear that some of the patients who developed ectasia after LASIK would have developed a related, ectatic, corneal condition called keratoconus, even in the absence of corneal surgery7. Concerning LASIK, Dr. Waxler, you further wrote, "The benefit is ~60% chance of temporary reduction in dependence on glasses or contact lenses." To support this claim, you cite, "P970053 Patient Information Booklet (p9 3rd bullet under #8)" and state, "This is a typical value for refractive lasers and better than some." This document is attached as Appendix 3.

First, it should be noted that the document you reference describes the results of treatment with a laser designed more than 20 years ago, tested more than 15 years ago, and approved by the FDA 12 years agoa laser that is not commonly used in the United States today and one that does not incorporate numerous technological advances that have occurred in the last two decades. Second, the document you cite pertains to PRK, rather than LASIK. Finally, the actual statement you reference states, "PRK may reduce or eliminate dependency upon contact lenses or glasses (60.6% could see 20/20 or better without glasses or contacts at 6 months)." Clearly, the document that you reference bears no resemblance to what you wrote in your letter.

The very next statement in the document you reference states, "PRK should be considered a permanent surgical procedure," in absolute contradiction to your statement that the document labels LASIK as a "temporary" procedure.

Dr. Waxler, you also state, "This is a typical value for refractive lasers and better than some." That statement is simply false. For example, 93.4 percent of patients achieved 20/20 or better vision at 6 months post-operatively with the WaveLight Allegretto Wave Excimer Laser System (see FDA, P020050/S004, page 34, Table 7, Study Cohort, Summary of Key Efficacy Variables Over Time), which was approved in 2003 (Appendix 4). Your letter to me also contains a graph, which you claim was taken from an article published by Pallikaris in 2001, showing what he says are visual complaints expressed by patients who have undergone LASIK. There are two major problems with this claim. First, the article you reference does not contain the chart you included in your letter to me. Second, it is important to show that the incidence of visual complaints after LASIK is higher than it was before LASIK, in order to conclude that LASIK caused them. Omitting the preoperative symptoms and claiming that LASIK is the cause of postoperative symptoms is misleading because many people notice visual symptoms with their glasses and contact lenses.

I was unable to determine where you obtained the graph that was included in your letter to me; however, the Summary of Safety and Effectiveness published by the FDA for the WaveLight Allegretto Wave Excimer Laser System, which was approved on October 7, 2003, states, "Patient reports of glare from bright lights, light sensitivity, night driving glare and visual fluctuations all improved after LASIK. The percent of subjects reporting 'none' or 'mild' of these symptoms improved after treatment" (Appendix 4). If these and other objective data from FDA-supervised clinical trials of modern excimer lasers had been reviewed by you, Dr. Waxler, you should have concluded that modern LASIK does not increase the incidence of visual symptoms.

In summary, your letter is filled with false statements, incorrect citations of the published literature, references that do not fairly represent the existing literature, incorrect reference to outcomes of PRK as if they were for LASIK, citation of results for a laser designed two decades ago as if it were representative of modern lasers, mischaracterization of results from older lasers as "better than most," reference of a graph that does not exist in the reference you cite, and misrepresentations of the actual performance of modern excimer lasers for the correction of refractive errors. A recent review of the world's literature on LASIK led to the conclusion that it is safe and effective, with outstanding results in the vast majority of patients8. Complex, visually demanding activities like night firing range performance and military helicopter piloting is as good or better without glasses in soldiers who have had refractive surgery as it is with glasses before surgery9, 10. In fact, laser refractive surgery is now commonly performed on our military personnel, including aviators and members of Special Forces units, whose lives, performance, and operation of multi-million dollar equipment depends on their ability to identify accurately and target the enemy in unfriendly environmental conditions. Based on this positive real-life military experience over the past decade, NASA approved LASIK for astronauts.

LASIK has been shown to be a safe and effective procedure for the correction of refractive errors by numerous studies around the world. It has a low complication rate that is acceptable to many patients and comparable to that of contact lenses over a lifetime. It serves to reduce or eliminate dependency on glasses and contact lenses for millions of patients around the world and has been found by the U.S. government to be acceptable for use by military personnel and astronauts. Advances in technology and techniques based on scientifically based studies have allowed the profession continually to improve the safety of LASIK. This is clearly a procedure that should be made available to patients who are properly informed about its risks and benefits.

Complications of LASIK still exist, and even their low rate is a concern to surgeons and ASCRS. The literature clearly shows that efforts of excimer laser manufacturers, physicians, ASCRS, and the FDA have improved LASIK outcomes over the years. We continue to work to produce better results for our patients and will not be satisfied until the complication rate for this procedure is effectively zero. EW

Sincerely, R. Doyle Stulting, M.D., Ph.D.

President American Society of Cataract and Refractive Surgery

References

1. Seiler T, Koufala K, Richter G. Iatrogenic keratectasia after laser in situ keratomileusis. J Refract Surg 1998; 14:312317.

2. Randleman JB, Russell B, Ward MA, Thompson KP, Stulting RD. Risk factors and prognosis for corneal ectasia after LASIK. Ophthalmology 2003; 110:267275.

3. Randleman JB. Post-laser in-situ keratomileusis ectasia: current understanding and future directions. Curr Opin Ophthalmol 2006; 17:406412.

4. Randleman JB, Woodward M, Lynn MJ, Stulting RD. Risk assessment for ectasia after corneal refractive surgery. Ophthalmology 2008; 115:3750.

5. Randleman, JB, Trattler WB, Stulting RD. Validation of the Ectasia Risk Score System for preoperative laser in situ keratomileusis screening. Am J Ophthalmol 2008; 145:813816.

6. Binder PS, Lindstrom RL, Stulting RD, Donnenfeld E, Wu H, McDonnell P, Rabinowitz Y. Keratoconus and corneal ectasia after LASIK. J Refract Surg 2005; 21:749752.

7. Wang JC, Hufnagel TJ, Buxton DF. Bilateral keratectasia after unilateral laser in situ keratomileusis: a retrospective diagnosis of ectatic corneal disorder. J Cataract Refract Surg 2003; 29:20152018.

8. Schallhorn SC, Farjo AA, Huang D, Boxer Wachler BS, Trattler WB, Tanzer DJ, Majmudar PA, Sugar A. Wavefront-guided LASIK for the correction of primary myopia and astigmatism; a report by the American Academy of Ophthalmology (Ophthalmic Technology Assessment). Ophthalmology 2008; 115:12491261.

9. Bower KS, Burka JM, Subramanian PS, Stutzman RD, Mines MJ, Rabin JC. Night firing range performance following photorefractive keratectomy and laser in situ keratomileusis. Mil Med 2006; 171:468471.

10. Van de Pol C, Greig JL, Estrada A, Bissette GM, Bower KS. Visual and flight performance recovery after PRK or LASIK in helicopter pilots. Aviat Space Environ Med 2007 78:547553.

Appendix

1. Letter from Dr. Waxler to Dr. Stulting dated May 7, 2010. Available at: http://www. lasiknewswire.com/MorrisWaxler_letter_to_DoyleStulting.pdf. Accessed September 9, 2010.

2. Maguen E, Rabinowitz YS, Regev L, Saghizadeh M, Sasaki T, Ljubimov AV. Alterations of extracellular matrix components and proteinases in human corneal buttons with INTACS for post-laser in situ keratomileusis keratectasia and keratoconus. Cornea 2008; 27:565573.

3. Patient Information Book for P970053.

4. Summary of Safety and Effectiveness for Wavelight Allegretto Wave Excimer Laser System http://www.accessdata.fda.gov/cdrh_docs/pdf2/P020050b.pdf.

ASCRS responds to LASIK critic Morris Waxler ASCRS responds to LASIK critic Morris Waxler
Ophthalmology News - EyeWorld Magazine
283 110
283 110
,
2017-04-06T09:14:02Z
True, 3