Lasik
Dr. Choe has been involved in the comanagement of refractive surgery patients since 1999. She can discuss the option for corrective surgery during your initial visit. She has worked with several Lasik surgeons in the atlanta area in the co-management of these patients. Below are some general questions and answers concerning Lasik. About LASIK Vision Correction Surgery LASIK
(Laser In-Situ Keratomileusis) is currently one of the most frequently performed elective procedures in North America. LASIK uses a cool beam of light from the excimer laser to gently reshape the front surface (cornea) of your eye.
Custom Lasik
While conventional LASIK has been a complete revolution in vision correction a newer form of laser vision correction technology exists called Custom LASIK. Custom LASIK is a procedure that enables a refractive surgeon to further customize the conventional LASIK procedure to your individual eyes.
Bladeless LASIK
In the LASIK procedure, a flap of corneal tissue must be created and then folded back. The cornea is the transparent dome-like structure that covers the iris and pupil of your eye. By creating a flap in the cornea, the surgeon is able to perform the laser vision correction treatment on the inner layer of the cornea and allows for a rapid visual recovery. With Bladeless LASIK surgery, the LASIK surgeon uses a laser to create the corneal flap. This technology gives the eye surgeon the ability to customize the corneal flap for each individual patient.
LASIK Eye Surgery: Treatment Types
Nearsightedness (Myopia)
With myopia, the eye is too long. This makes distant objects blurry, because light is focused in front of the retina. Near objects remain clear.
When LASIK surgery is performed for myopia, most of the laser pulses are applied to the central cornea, making it flatter. This reduces its focusing power and allows light to focus perfectly on the retina.
Farsightedness (Hyperopia)
With hyperopia, the eye is too short and light rays focuses behind the retina. Hyperopia causes blurry vision up close and sometimes in the distance. Hyperopia must be distinguished from presbyopia, which is the inability of the eye to focus sharply on nearby objects, resulting from loss of elasticity of the lens with advancing age.
When LASIK eye surgery is performed for hyperopia, most of the laser pulses are applied to the peripheral cornea. This is like removing a "doughnut" of corneal tissue, making it steeper. This brings light rays from behind the retina to focus perfectly on it's surface.
Astigmatism
Astigmatism causes light entering the eye at different axes to be focused at different amounts. For example, light entering vertically (from 12 o'clock to 6 o'clock) may be focused more than light entering horizontally (from 9 o'clock to 3 o'clock). With astigmatism, the shape of the cornea is like a football compared to a basket ball which is perfectly round.
The net result of astigmatism is blurred vision. Often letters appear slanted or with "tails" coming off of them.
The net result of astigmatism is blurred vision. Often letters appear slanted or with "tails" coming off of them.
When LASIK surgery is utilized for astigmatism, the laser pulses are applied to the steeper areas, selectively giving a more round shape to the cornea.
Monovision
Monovision is correcting one eye for distance vision and the other eye for near vision. LASIK surgery cannot correct presbyopia so that one eye can see at both distance and near. However, LASIK eye surgery can be used to correct one eye for distance and the other for near. If you can adjust to this correction, it may eliminate or reduce your need for reading glasses. Our surgeons often recommend partial monovision for patients over forty to delay the need for reading glasses. This blended vision is usually very well tolerated by patients.
For patients with early cataracts and who wish to have refractive surgery, an excellent option would be bilateral Restore lenses implanted inside the eye, after the lenses or cataracts have been removed.
The following is a guideline of treatable ranges. The doctor will determine your candidacy only after a thorough eye exam.
Generally, you are a GOOD CANDIDATE for vision correction surgery if you:
-Are nearsighted up to minus 12.00 diopters
-Are farsighted up to plus 6.00 diopters
-Have astigmatism up to 4.00 diopters
-Have pupil width up to 8.0 diopters
-Are at least 18 years of age
-Had a stable eyeglasses or contact lenses prescription for at least one year
-Are in good general health
-Are farsighted up to plus 6.00 diopters
-Have astigmatism up to 4.00 diopters
-Have pupil width up to 8.0 diopters
-Are at least 18 years of age
-Had a stable eyeglasses or contact lenses prescription for at least one year
-Are in good general health
Generally, you are NOT A GOOD CANDIDATE for vision correction surgery if you:
-Have certain eye diseases, such as cataracts, glaucoma or connective tissue disease.
-Have corneal abnormality such as keratoconus or pseudo-keratoconus with irregular astigmatism.
-Have severe dry-eye syndrome.
-Have certain eye viruses, such as herpes simplex and herpes zoster
-Have certain health problems, such as uncontrolled diabetes, autoimmune or collagen vascular disease or any condition that weakens your immune system
-Take certain medications that weaken your immune system
-Are pregnant, nursing or plan to become pregnant in the next six months
-Are in a profession that prohibits vision correction surgery
-Have corneal abnormality such as keratoconus or pseudo-keratoconus with irregular astigmatism.
-Have severe dry-eye syndrome.
-Have certain eye viruses, such as herpes simplex and herpes zoster
-Have certain health problems, such as uncontrolled diabetes, autoimmune or collagen vascular disease or any condition that weakens your immune system
-Take certain medications that weaken your immune system
-Are pregnant, nursing or plan to become pregnant in the next six months
-Are in a profession that prohibits vision correction surgery
How is Laser Vision Correction performed?
- The LASIK Procedure
LASIK eye surgery is a two-step procedure:
STEP ONE
An instrument called a microkeratome lifts the thin surface layer of the cornea away from underlying
layers in a process known as making a corneal flap or cap.
layers in a process known as making a corneal flap or cap.
Flap creation begins with the instillation of anesthetic
eye drops. A suction ring is then centered around the cornea and a vacuum is generated to hold the ring on the eye. During the few seconds the vacuum is on, the vision grows dim and a mild pressure sensation is felt.
eye drops. A suction ring is then centered around the cornea and a vacuum is generated to hold the ring on the eye. During the few seconds the vacuum is on, the vision grows dim and a mild pressure sensation is felt.
The microkeratome is then attached to the suction ring and passes across the surface of the cornea to create the flap.
After the microkeratome pass, the vacuum is released, the suction ring is removed from the eye and the protective corneal flap is lifted and reflected off to the side. (Flipped open like the cover of a book.) The middle layer of the cornea is thereby exposed for the upcoming laser treatment.
STEP TWO
The laser treatment usually lasts anywhere from a few seconds up to a minute, depending on the amount and type of correction needed.
The patient is asked to look at a blinking target light. Then, the surgeon focuses the laser on the exposed middle layer of the cornea. A foot pedal is depressed to activate the laser.
While the laser is running, it makes a rapid ticking sound. Each tick represents an individual pulse of the laser.
After the laser reshapes the cornea, a small amount of fluid is used to wash away microscopic debris. The protective corneal flap is then gently folded back into place, like closing the cover of a book. In a few short minutes, natural adhesive forces seal it in place without the need for sutures.
The above procedures are then repeated for the second eye.
What are the possible side effects or complications?
Most patients have wonderful vision after LASIK surgery, and if we have determined that you are a good candidate for the procedure chances are you too will be very satisfied with your vision.
Although all LASIK candidates go through a very selective screening process and the most gentle and most precise surgical techniques available are used, minor irritations that last a few days sometimes occur. The following is a brief discussion of possible side effects and complications of LASIK. Some are common and some are extremely rare.
-The most common side effect after LASIK is "dry eyes". This usually lasts a few days, and resolves spontaneously. Rarely this may cause intermittent blurred vision, and persist for up to three months. It can be helpful to place "punctum plugs" in the lower eyelids. This quick and painless office procedure reduces the normal drainage of tears into the nose, and keeps the eyes moist. Temporary plugs which dissolve after 90 days are often used. Permanent plugs last indefinitely and might be recommended as an alternative. An extra charge is applied for this procedure.
-Some patients experience night-time glare and halo effect around headlights or neon signs after LASIK. This typically resolves after 4-6 weeks. It is more severe in patients with high corrections and large pupils. Pre-existing night-time visual difficulties may be unchanged after LASIK. Custom ablation using Wavefront technology has a greater chance of reducing night-time glare and halo.
-Some patients require enhancement surgery to improve their vision after LASIK. This might occur in 5-15% of patients. Patients with high prescriptions, or who have had prior refractive surgery such as RK, are more likely to require an enhancement. It is important to wait 4-12 months to allow the vision to completely stabilize before an enhancement is considered. Occasionally, temporary glasses or contact lenses may be necessary during the waiting period.
-Eyestrain might occur if the vision is slightly different in the two eyes after LASIK. "Mono-vision" or "partial mono-vision" is often planned to allow the dominant eye to see at a distance, and the non-dominant eye to read up close. It is important to allow the eyes to work together and allow the brain to adjust to this vision. It is not helpful to compare the vision in the two eyes. Patients receiving mono-vision usually require reading glasses as they age for very small or detailed close work.
-Flap complications rarely occur. In order to obtain an excellent result, a perfect flap is required. In less than 1 in 1000 procedures the flap is either incomplete, has an irregularity or other problem. If such a situation arises, it is best for the procedure to be stopped, allow the eye to stabilize and continue the procedure a few months later. Most patients do very well if such an event occurs. Contact lens patients are usually permitted to wear their lenses during this waiting period.
-Dislocated flap . The flap may shift after LASIK, especially within the first 24 hours. This can cause visual distortion and requires prompt attention. Often this can easily be dealt with in the exam room, but sometimes a return trip to the OR is necessary. Avoid rubbing the eyes or getting debris in the eyes, especially for the first two weeks after LASIK.
-Inflammation under the flap (DLK) can arise. The cause of DLK is unknown, but DLK responds very well to frequent use of cortisone eye drops and tablets. Sometimes irrigation under the flap is helpful to speed up the resolution of the inflammation.
-Infection under the flap occurs in less than 1 in 10,000 procedures and responds well to treatment. It is important to keep all follow-up visits and report any redness, pain, blurred vision, or discomfort.
-Ectasia is a condition where the cornea progressively thins and becomes irregular after LASIK. LASIK is not recommended for persons with thin corneas or who may be predisposed to develop ectasia.
-Some patients experience night-time glare and halo effect around headlights or neon signs after LASIK. This typically resolves after 4-6 weeks. It is more severe in patients with high corrections and large pupils. Pre-existing night-time visual difficulties may be unchanged after LASIK. Custom ablation using Wavefront technology has a greater chance of reducing night-time glare and halo.
-Some patients require enhancement surgery to improve their vision after LASIK. This might occur in 5-15% of patients. Patients with high prescriptions, or who have had prior refractive surgery such as RK, are more likely to require an enhancement. It is important to wait 4-12 months to allow the vision to completely stabilize before an enhancement is considered. Occasionally, temporary glasses or contact lenses may be necessary during the waiting period.
-Eyestrain might occur if the vision is slightly different in the two eyes after LASIK. "Mono-vision" or "partial mono-vision" is often planned to allow the dominant eye to see at a distance, and the non-dominant eye to read up close. It is important to allow the eyes to work together and allow the brain to adjust to this vision. It is not helpful to compare the vision in the two eyes. Patients receiving mono-vision usually require reading glasses as they age for very small or detailed close work.
-Flap complications rarely occur. In order to obtain an excellent result, a perfect flap is required. In less than 1 in 1000 procedures the flap is either incomplete, has an irregularity or other problem. If such a situation arises, it is best for the procedure to be stopped, allow the eye to stabilize and continue the procedure a few months later. Most patients do very well if such an event occurs. Contact lens patients are usually permitted to wear their lenses during this waiting period.
-Dislocated flap . The flap may shift after LASIK, especially within the first 24 hours. This can cause visual distortion and requires prompt attention. Often this can easily be dealt with in the exam room, but sometimes a return trip to the OR is necessary. Avoid rubbing the eyes or getting debris in the eyes, especially for the first two weeks after LASIK.
-Inflammation under the flap (DLK) can arise. The cause of DLK is unknown, but DLK responds very well to frequent use of cortisone eye drops and tablets. Sometimes irrigation under the flap is helpful to speed up the resolution of the inflammation.
-Infection under the flap occurs in less than 1 in 10,000 procedures and responds well to treatment. It is important to keep all follow-up visits and report any redness, pain, blurred vision, or discomfort.
-Ectasia is a condition where the cornea progressively thins and becomes irregular after LASIK. LASIK is not recommended for persons with thin corneas or who may be predisposed to develop ectasia.
In summary, millions of people now enjoy the miracle of LASIK refractive surgery. The procedure is safe and effective. Major complications are extremely rare especially when proper pre-operative, surgical, and post-operative protocols are maintained.