What is LASIK?
Refractive Errors (need for glasses or contacts) occur when the surface of the eye (the cornea) is too steep (in near-sightedness), too flat (in far-sightedness) or has uneven curves (in astigmatism). This results in the images not being focused sharply on the retina and hence, causing blurry vision.
LASIK stands for laser in-situ keratomileusis (LASIK).”Keratomileusis” is derived from the Greek word that literally means “to shape the cornea.” “In-situ” means “in place.” Therefore, the term LASIK means “to reshape the cornea in place using a laser.
One of the most popular ways to correct vision is with a procedure called LASIK (laser in-situ keratomileusis), which uses a laser to change the curvature of the cornea (outer window of the eye). LASIK has quickly become the procedure of choice for most patients because they recover quickly and have fewer side effects and complications than with other methods of vision correction. In fact, most LASIK patients notice a significant improvement in their vision soon after surgery. LASIK removes tissue within the cornea to treat low to high levels of nearsightedness, farsightedness and astigmatism. Astigmatism can be treated at the same time as nearsightedness and farsightedness.
The LASIK procedure combines two sophisticated techniques of surgery to correct refractive errors. The first technique involves the use of the femtosecond (Intrlase or Zeimer) laser, to create a thin protective layer of corneal tissue that covers the area to be sculpted by the laser. This flap allows for rapid recovery of vision and reduces discomfort after surgery. The second technique uses a computer-controlled excimer laser — a cold, invisible, ultraviolet laser — to sculpt the underlying cornea, correcting the refractive error. This is the same laser that is used in PRK. The protective layer of superficial corneal tissue is repositioned without sutures and is secure after a few minutes so that a patch is not required. Visual recovery is typically rapid, and there is little or no post-operative pain. Eye drops need only to be taken for a week.
Excimer laser vision correction has come a long way since it was first invented 25 years ago. First we started doing PRK to reshape the cornea to correct vision problems. While this was successful, visual recovery was long and there was postoperative discomfort. So LASIK was introduced, which is essentially the same procedure as PRK, except it was done under a flap. This eliminated the postoperative discomfort and allowed for rapid visual recovery with all patients being able to return to work the day after surgery. The flap was created with a device called a mickrokeratome. Because this involved the use of a blade which had the potential for serious problems, a new technology the femtosecond laser (bladeless laser) technology evolved. Flaps are now created with a laser so the procedure is 100% blade free. Early on there were night vision problems such as halos and glare. To address this issue Wavefront technology evolved with sophisticated algorithms and large treatment zones and blending zones which virtually eliminates the potential for halos and glare. With the combination of Femtosecond and Wavefront technologies each individual treatment can now be customized to treat each individual eye with many patients seeing better than they ever saw with their glasses or contact lenses. The technology is now so safe and accurate that it was recently approved for Navy fighter pilots and for NASA astronauts.
20/40 is the vision required to pass the drivers test in the State of Texas. Recent FDA studies for the Customvue demonstrated 20/20 vision in 98% of patients studied. With Wavefront Optimized treatements over 50% of our patients get better than 20/20, i.e. 20/15 vision. A combination of the intralase and new wavefront technologies has the potential for getting even better results.
In experienced hands the complications of LASIK are extremely rare. Most of the complications relate to the creation of the flap and are thus dependent on surgical skill. However now with the new bladeless femtosecond technology these complications are almost non existent. The worst possible complication would be an infection with a permanent central opacity or a wrinkled flap requiring a cornea transplant. Since Dr. Abbas is an experienced cornea transplant surgeon he is ideally suited to deal with any serious complications relating to the flap and since he routinely performs Cornea Transplants he would be best suited to deal with this problem which to date has not occurred in any one of our LASIK patients. Other complications beside the flap relate to the Laser itself.
Possible side Effects
Even though the refractive error may be corrected and the visual acuity may be good after LASIK, some patients experience one or more of the following side effects of the procedure:
– Optical Aberrations: As with any refractive procedure, it is common for patients to notice halos, ghost images, shadows, and slight distortions for the first months after surgery. In unusual circumstances, these optical aberrations may interfere with normal visual activities. The new wavefront technology based treatment algorythems have all but eliminated this problem.
– Night myopia: Because only the central portion of the cornea is reshaped, eyes may become more nearsighted when the pupil dilates and allows light to enter through the peripheral cornea that had not been reshaped. Even if excellent unaided vision is obtained during the daytime, a thin pair of glasses may be required at night for optimum vision in rare instances.
– Dry Eye: During the healing process, your eye may feel dry, and you may need to use artificial tear replacement for comfort temporarily. In 7% of individuals dry eyes can persist for 6 to 8 weeks or longer. This is because we cut through corneal nerves when we make the corneal flap. These nerves normally send a signal to the gland that makes the tears and this signal is interrupted with the creation of the flap. Fortunately these nerves grow back and normal tear function is restored. You will undergo a thorough evaluation prior to LASIK to make sure your eyes are not too dry or whether they may need to be pretreated to increase your tears prior to the LASIK procedure. If your eyes are dry after LASIK you will be treated with drops and plugs if necessary.
– Discomfort: Most of the discomfort following LASIK occurs within the first 24 hours and can be controlled with frequent artificial tears. The eyes may be transiently more sensitive to sunlight following surgery.
Consider these important points when you are making your LASIK vision correction decision:
– Rapid Recovery — Most patients are back to work the day after surgery. There is typically very little pain, and patients recover vision within the first 24 hours, because the epithelium is minimally disrupted.
– Correction of all refractive errors – Myopia, Hyperopia and Astigmatism(up to -12D for Myopia, 4D for Hyperopia and 4D for Astigmatism)
– Repeatability — In the case of under-correction or overcorrection, LASIK may be repeated by lifting the pre-made flap and adding additional laser treatment.
– Long-term Stability — Because there is minimal disruption of the normal corneal architecture and minimal wound healing, it is likely that there will be minimal refractive change over time.
– Structural Integrity — The flap is secure after the first day, and the eye is not weakened as it is with RK.
– No Scarring — There is little or no scarring in the central cornea, as can occur with PRK.
– No Need for Long-term Post-operative Eye Drops — There is no need to suppress wound healing with the use of steroids as there is with PRK. LASIK patients can stop eyedrops much more rapidly after surgery.
While when weighed against the many advantages, the potential disadvantages to LASIK vision correction are few, they should be considered nonetheless:
– Requires a Skillful Surgeon — Because of the complexity of the microkeratome, manual dexterity and operative experience are required.
– Cost – LASIK is typically more expensive than PRK.
Bladeless Intralase Technology
This very latest technology creates the flap with a laser which offers several advantages over regular microkeratomes:
- – reduced risk of vision threatening complications
- – more accurate depths of flap (very important in thin corneas)
- – more accurate and reproducible results
- – less need for enhancement
- – true individualized customization of treatment
For more information on this technology click here.
If you are interested in laser vision correction call us at 281-420-EYES (3937) to set up for a FREE LASIK CONSULTATION or Schedule Online.