LASIK or IntacsTM - Which is right for you?
For a patient considering vision surgery there is a veritable alphabet soup of treatment choices -- LASIK, PRK, RK, LTK, IOLs, SRP, and Intacs. Each procedure has a different set of vision problems that it treats and each has a different group of patient characteristics that are to be considered. Some treatments are currently available in the United States; others are still in clinical trials or can be obtained overseas. This article will compare and contrast two procedures that use devices that have been approved by the FDA for the treatment of myopia, or nearsightedness: LASIK and corneal ring inserts, commercially known as IntacsTM.
Briefly, LASIK is a laser surgery procedure that involves the removal of tissue of the cornea of the eye in order to adjust how images are focused. A flap of cornea tissue is cut and laid back, and with the help of the computer, a laser is used to sculpt the cornea tissue underneath, then the flap is replaced. The Intacs procedure involves the surgical placement of two curved inert inserts into the cornea of the eye. The inserts flatten the cornea, correcting its refractive errors. As is evident from these two descriptions, LASIK and Intacs are two very different approaches to treating the same vision problem. To focus the examination of these two procedures, they will be compared as to several criteria: range of myopia and astigmatism treated, surgical complications, and other risks, results, and cost.
Range of Myopia and Astigmatism Treated
A good starting point for the comparison between LASIK and Intacs for many people is the range of myopia and astigmatism that can be treated because this one consideration can make the decision for the patient. LASIK is remarkably versatile in the degree of myopia and astigmatism that it can treat. In general, although the results are less predictable with worse beginning vision, LASIK can treat myopias that need correction of up to and including -10 diopters. Astigmatisms of up to 5 diopters generally result in acceptable vision outcomes. The boundaries of this are being pushed with more and more refinements of the procedure. In addition, each different type of excimer laser technology used for this treatment is continually receiving increases to the approved perimeters of treatment.
In contrast, Intacs have a relatively narrow range of myopias and astigmatisms that can be treated. According to Keravision, the company who manufactures the cornea inserts, the prescription of a good candidate for their eyeglasses or contacts should be between -1.00 and -3.00 diopters, with no more than 1.00 diopter of astigmatism, and the prescription should have been relatively stable for at least one year. A good candidate would have healthy eyes, free from disease or injuries, and be at least 21 years of age. This describes someone that has relatively mild myopia. Thus, it is important before researching the Intacs option thoroughly to determine that your vision falls within the range that can be treated using this technique. If you do, however, the following considerations can be among those that you weigh in making a choice.
Surgical Complications and Other Risks
Both surgical procedures tend to have a very low incidence of complications. According to the American Academy of Ophthalmology, complications such as blurred vision or nighttime glare occur in only one to five percent of all LASIK patients. The percent of various complications for the insert of Intacs appears even lower, a little over one percent of the time overall. The lower incidence may be due to the involvement of only the outer edge of the cornea in the surgery with this procedure, which does tend to reduce the chance of adversely impacting sight in the eye.
The overall potential lifetime risk is a major difference between the two procedures. Unlike LASIK, which involves the permanent removal of tissue from the eye, the Intacs are removable if complications should occur or the results are less than satisfactory. However, the significance of being able to remove the inserts needs to be interpreted cautiously. "There is no data to show if after three or four years of wearing Intacs the eye reverts to its pre-surgical state upon removal," comments Dr. Stanley Teplick, a vision surgeon based in Portland, Oregon who is certified in both the LASIK and Intacs procedures. "The only data is from patients who had the inserts removed after infection or some other complication immediately after surgery. There, the eyes did revert, but after long term insertion it is still uncertain."
Nevertheless, if having the possibility of being removed or explanted is important to you, this consideration could be an argument to look very closely at the Intacs option.
Both LASIK and Intacs provide very good results on a percentage basis for those whose initial vision fall within the ranges recommended for the treatments. As the initial vision gets worse, the outcomes do tend to become less acute. As provided by the International Society for Refractive Surgeons, LASIK provides for low and moderate myopia (up to about 10 diopters), an achievement of 95 percent of eyes typically achieve 20/40 or better vision in 95 percent of eyes, with 85 percent having 20/25 or better vision. Only one percent of eyes cannot see as well with glasses after LASIK surgery as they could with glasses before surgery. For high myopia (over 7 diopters), 90 percent of eyes typically achieve 20/40 or better vision, with 70 percent of eyes typically achieving 20/25 or better vision. Five percent of eyes beginning with high myopia cannot see as well with glasses after surgery as they could with glasses before surgery.
Keravision provides these statistics for outcomes with the Intacs procedure: 12 months post-surgery 53 percent of the eyes have 20/16 vision or better, 74 percent have 20/20 vision or better, 87 percent have 20/25 vision or better, and 97 percent have 20/40 vision or better. These two sets of statistics are not directly comparable because of the differences in starting vision between the two sets of patients, that is, even the "low or moderate" myopia LASIK group includes more patients with worse starting vision. On this subject, Dr. Teplick states that "patients considering the two procedures should know that LASIK results are very, very good in the exact range that Intacs are effective." In any case, it is evident that both procedures provide an excellent chance of having very good, even superlative, vision after the procedures.
In general, there is very little difference in cost between the two procedures. Many U.S. surgeons charge about $1,800 to $2,800 per eye for an initial LASIK procedure, but the price will vary depending upon the conditions specific to the patient and area. The Intacs procedure also runs about $2,000 per eye.
In the final analysis, it is important to discuss any decision about having LASIK surgery or Intacs inserted) carefully with your ophthalmologist. A first consideration is whether your vision error is sufficiently mild to use the Intacs procedure to correct it. If not, you should consider LASIK or one of the other surgical procedures that corrects more severe vision problems. If your myopia is mild, however, and the irreversible nature of LASIK is worrisome, the Intacs procedure may be a good choice for you. In the end, it is comforting to know that whatever choice you make, you have an excellent chance of coming away from the procedure with very good vision and the freedom of living without the need for lenses to correct your nearsightedness.