Portal de Periódicos da CAPES

It’s the Retina, Stupid

2001; Lippincott Williams & Wilkins; Volume: 78; Issue: 4 Linguagem: Inglês

10.1097/00006324-200104000-00001

1538-9235

Karla Zadnik,

Ophthalmology and Visual Impairment Studies

It is well documented that there are increased risks for eye disease associated with moderate to high myopia. Specifically, those risks begin at myopia on the order of −6.00 D and include posterior subcapsular cataracts, 1 open angle glaucoma, 2 intraocular pressure that elevates with topical steroid use, and retinal detachment. 3 In fact, myopia is still the seventh leading cause of legal blindness in the United States today. Millions of patients are having their myopia eradicated by refractive surgery. In 2000 alone, over 800,000 Americans underwent laser-assisted in situ keratomileusis (LASIK), of whom a quarter had myopia of at least −6.00 D. 4 That number may double this year. The average age of patients undergoing LASIK is over 40 years. 4 That means the risky years for retinal detachment, glaucoma, and cataracts are on the horizon. Here's the problem. There appear to be no widespread efforts to retain information about the patient's preoperative refractive status. In today's mobile society, it is likely that the patient will eventually be cared for by an eye care practitioner who will know only that the patient underwent LASIK, but he or she will not know the magnitude of the patient's pre-surgical refractive error. To the best of my knowledge, LASIK patients are not routinely given any information on their pre-surgical myopia in a way that can be retained into the long-term future. They are not rigorously counseled on the risks of eye disease that continue to accompany the myopic, stretched status of their retinas, even though the symptoms of myopia have been reduced substantially. Let's eavesdrop on a typical conversation between optometrist and patient 10 years in the future: Doctor: "I see that you had LASIK performed during that refractive surgery boom at the turn of the century. Now that you are 50 years old, I want to be sure you don't have any internal eye problems." Ms. 20/Happy: "What do you mean, internal eye problems? I'm just here for a tune-up on my reading glasses." Doctor: "You used to be nearsighted, right? You wore glasses that had thicker edges than centers, that made your eyes smaller behind them, and your contact lens packages had a minus sign before the power, right?" Ms. 20/Happy "I don't remember much about that. What about my reading glasses?" Doctor: "There are serious eye diseases that nearsighted people are at increased risk of developing, like retinal detachment, cataracts, and glaucoma. I will do a complete eye examination today, including examining your eyes through dilated pupils, to check for those problems." Ms. 20/Happy: "But, Doctor, I'm not nearsighted any more. How can I still be at risk for those problems? Besides, those sound like old people's problems." Doctor: "It's true. You're not nearsighted any more from an optical point of view, but nearsightedness is caused by an eyeball that's too long. The LASIK procedure just flattened the front to compensate for your oversized eye. It didn't shorten the eye or make the tissues at the back of the eye normal again. The risk increases dramatically when a person has a certain amount of myopia. Do you remember how nearsighted you were before the surgery?" Ms. 20/Happy: "Nope. I don't remember. And my refractive surgeon is performing lid tucks now, so he discarded all his refractive records a few years ago. Can't you just examine my eyes and let me know if I have any of the bad stuff?" Doctor: "Without information on whether you were highly myopic before surgery, it's difficult for me to assess your risk accurately. However, let's get started, and we can discuss the symptoms of those eye problems and how often I should examine you in the future." Ms. 20/Happy: "Great. You're the doctor." The above scenario will play out all over the country in the years to come. Not only are the pre-operative measurements important in quantifying the risks listed above but they are vital for cataract surgery. 5 The problems with intraocular lens power estimation in the post-refractive surgery patient are well documented. 6, 7 The corneal topography following myopic refractive procedures results in an underestimation of intraocular lens power and less-than-happy hyperopic pseudophakes. Pre-operative refraction and corneal power data are necessary to ensure optimal post-operative outcomes. 8 As life expectancy increases, a high proportion of LASIK patients will require a cataract extraction. Post-operative corneas are not inscribed with the pre-operative spherical equivalent. Old glasses and contact lenses will likely perish in the laser center's monthly ceremonial pyre. Refractive surgery patients should be given a card that says, "I used to be a −7.50 D myope with +44 D corneas" with a reminder about the importance of regular, dilated, retinal examinations on the back. They should be urged to inform new eye doctors about their refractive history when they change practitioners and be educated about the symptoms of retinal detachment. Granted, electronic records and more savvy patients may mean that some information will be retrievable in the future. Nonetheless, the eye care practitioners of the present need to step up and educate the myopic patients of today. I thank Mark Bullimore and Paul Karpecki for their input on this editorial. Karla Zadnik The Ohio State University College of Optometry Columbus, Ohio