Laser Vision Correction
ASA
ASA is for those who:
What to expect on surgery day
During ASA
Advanced Surface Ablation
ASA was the first procedure performed using the Excimer laser. It corrects vision by reshaping the cornea. The difference between LASIK and ASA is that with LASIK a corneal flap is created and the laser is applied to the inner tissue of the cornea. With ASA, the epithelium (or outer skin of the cornea) is removed and a laser is applied to the surface of the cornea.
ASA can be used to correct low to high levels of nearsightedness, farsightedness and astigmatism.
To treat nearsightedness, the steep cornea is made flatter by removing tissue from the center of the cornea. This moves the point of focus from in front of the retina to directly on the retina.
To treat farsightedness, the flat cornea is made steeper by removing tissue outside of the central optical zone of the cornea. This moves the point of focus from behind the retina to directly on the retina.
To treat astigmatism, the cornea is made more spherical -- like a basketball instead of a football. This eliminates multiple focusing points within the eye and creates one point of focus on the retina. Astigmatism can be treated at the same time as nearsightedness and farsightedness.
ASA is for Those Who:
- want to reduce or eliminate their dependence on glasses or contacts
- are over 18 years of age
- have had a stable eye prescription for at least one year
- have no health issues affecting their eyes
- have corneas too thin for LASIK
What to expect on surgery day:
You will arrive at Eye Care Specialists about an hour prior to your procedure. Once you have been checked in you may be offered a sedative to help you relax. You will then be prepared for surgery. The area around your eyes will be cleaned and a sterile drape may be applied around your eye. Anesthetic eye drops will be used to numb your eyes; no injections or needles will be used. When your eye is completely numb, an eyelid holder will be placed between your eyelids to keep you from blinking during the procedure.
Next, your doctor will remove the epithelium, a thin layer of protective skin that covers the cornea. You will be asked to look directly at a target light while the laser reshapes your cornea. The laser will be programmed with the information gathered in your pre-operative exam. The laser treatment will be completed in less than a minute or two, depending on the amount of correction needed.
Following your procedure, your eye(s) will be examined with a slit lamp microscope. Your eyes may be shielded for protection. Your vision may be somewhat blurry or hazy for up to 7 days. You will experience some discomfort as the epithelium heals and covers the treated area. Eye drops, pain medication and possibly a protective contact lens can be used to minimize this discomfort. Most patients resume normal activities within one to three days. Vision can fluctuate for up to three months.
During ASA
- The typical ASA procedure takes less than five minutes. Each step will be explained to you by the doctor as it is performed.
- An eyelid holder will be placed in your eye to prevent you from blinking. You will feel a little pressure, but no discomfort, as the anesthetic drops will have taken effect.
- The doctor will then treat your eye to remove the surface layer, either using the laser or a manual instrument. Both methods are painless. The surface layer is naturally replaced by your body within three days.
- You will be asked to stare at the red target light.
- The laser will make a clicking sound as it works.
- Most ASA procedures take less than 30 seconds of actual laser time.
- It is not uncommon for patients to move their eyes during the procedure. A little movement does not cause any undue risk or danger to your eye, but you should try to remain as steady as possible.
- The laser can be stopped and started precisely within a fraction of a second. The doctor maintains control throughout the procedure.