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LASIK LASIK Laser in-situ keratomileusis, or LASIK, is a surgical procedure that is able to correct a wide range of nearsightedness (myopia), farsightedness (hyperopia) and astigmatism. LASIK combines the precision of the excimer laser that is used in PRK surgeries with the flap technique that characterizes ALK. LASIK has been performed internationally for approximately 10 years. It was first performed in clinical trials in the U.S. in 1991. It is important to note that the major components of the procedure have a long history. Ophthalmologists have been reshaping the cornea for over 50 years, creating a protective layer of tissue for over 35 years, and using the excimer laser since the 1980s. Click here to read more regarding The Do you Qualify for LASIK Surgery? There are FDA regulations governing which particular excimer laser may be used to correct which particular type and degree of refractive error. For instance, one excimer laser was recently approved for LASIK treatment of nearsightedness up to -14.0 diopters with or without up to -5.0 diopters of astigmatism. These are high amounts of refractive error and include most nearsighted people. But there are quite a few people with more than -14.0 diopters of nearsightedness, and the FDA feels they will not achieve a satisfactory result. Read more about qualifications. Before Your Surgery Normally for your consultation, you'll visit with a refractive counselor who will determine if you are a candidate for laser vision correction. You'll learn about the various procedures to correct nearsightedness, farsightedness, and astigmatism, what outcomes you can expect, the recovery process, risks and other considerations, and cost. Prior to initiating the LASIK for myopia (nearsightedness), hyperopia (farsightedness), or astigmatism, you will need to undergo a series of preoperative tests, in order to make certain that you get the most accurate correction and follow-up possible. Some of the preoperative tests are as follows:
Repeating these tests help ensure accuracy and predictability so don't be concerned if some of the tests are repeated several times preoperatively. Once your testing is completed and after your consent forms are signed, you will be taken to the preoperative area. The preoperative steps surgeons take vary slightly from practice to practice. They may include measuring the thickness of the patient's cornea with an ultrasonic probe (a process called pachymetry), placing a drape around the eye to pull back the eyelashes, and positioning an instrument called a speculum to hold the patient's lids open. Your surgeon will talk with you about the preoperative protocal he or she follows. To ensure your comfort and confidence, your head and neck are kept snug in an inflatable pillow, your lids are kept open with a speculum and your eyes are treated with numbing drops that prevent your eye from reacting to stimuli. You may also be given an oral sedative if necessary. After patients are given a topical anesthetic (eye drops) to numb the eye (so they experience no pain), the surgeon applies the vacuum ring, the patient experiences a sensation of pressure just before his or her vision fades for a few seconds. The microkeratome - the instrument the surgeon uses to create the flap - and the laser do not cause any pain or discomfort. For several hours after the procedure, many patients describe a mild burning sensation, such as after opening the eyes while swimming in chlorinated water. After the first few hours, this uncomfortable feeling usually subsides. To treat nearsightedness with LASIK Laser Vision Correction, the cornea must be made flatter. This is accomplished by removing tissue from the center of the cornea. To treat farsightedness with LASIK Laser Vision Correction, the central cornea must be made steeper. This is accomplished by directing the laser beam to remove tissue from around this area. To treat astigmatism with LASIK Laser Vision Correction, the cornea must be made more spherical. By changing the pattern of the beam, tissue is removed in one direction more than the other. The technology associated with laser vision correction has a number of built in safety measures. Throughout the procedure, the surgeon is observing your eye and tracking your eye movements through the microscope. With any large deviations, the surgeon will simply stop the laser ablation and restart the process when the eye is perfectly aligned. Although eye movement is a concern of many patients, those who have experienced the LASIK laser vision correction procedure rarely note a problem-maintaining fixation throughout the short laser ablation. At this point, the patient is moved to a postoperative room. The surgeon may or may not place a protective shield over the eye. Post-operative procedures differ from practice to practice, and patients should discuss the post-operative procedure with their surgeons. The day of the procedure it is best to keep both eyes closed and rest or sleep for the first few hours. Swimming is not recommended for the first week unless you wear watertight goggles. Also, avoid rubbing or bumping the eyes for the first few days and contact sports for the first few weeks. During the first 24-48 hours after the treatment, most patients will experience a sensation in the eye and/or some discomfort. Characteristically, the patient will notice improved vision within 3-5 days or sooner following the treatment. Treatment follow-up generally involves several visits to the doctor. Vision may fluctuate over the next few weeks, and usually stabilizes within three months. Benefits
of LASIK: When comparing only the benefits of LASIK over PRK the first impression is that LASIK has the potential to be a superior procedure. There is however, a very significant list of potential complications or risks and these include:
• Failure of automated instrument to leave a hinge on the corneal
flap, with the first incision. The overall complication rate for the ALK-E or LASIK in February 1995 was still in the order of 10% in the hands of the world leading innovators in the technique, although recent improvements in the technology have reduced that rate substantially Post-Operative
Enhancement Every patient and surgeon wants to achieve perfect vision correction with one surgical procedure. Although it is rare, on occasion the desired amount of refraction may not be achieved during the initial surgery. On these occasions it might become necessary to schedule an enhancement. An enhancement is a small additional surgery performed in an attempt to correct any initial miscalculations in refraction from the initial surgery. Most surgeons wait three to six months after the first surgery before performing an enhancement procedure, however there are exceptions. Check our news link for recent developements.
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