Laser eye surgery for astigmatism involves numbing the eyeball and making a very small incision in the cornea to reshape it. An ultraviolet laser emits pulsating light onto the cornea that regulates the shape with precise measurements guided by a computer. The eyelid is held open with a speculum, and a small ring prevents the eye from moving during the procedure. The patient returns home after surgery, and complete healing takes a few days to a few months, depending on the type of laser surgery performed.
Laser assisted in situ keratomileusis (LASIK) is a common form of eye surgery for astigmatism, and is a pain-free and simple method of vision correction. The surgeon adjusts the laser beam for individual patients’ lens shapes. While the patient looks at a light, the ultraviolet rays convert the cornea into a more normal shape. The reshaping usually takes less than five minutes per eye.
Photorefractive keratectomy (PRK) is an alternative method of laser eye surgery for astigmatism. It reshapes the surface of the cornea instead of treating the underside of the cornea, as LASIK does. One disadvantage of this type of laser eye surgery for astigmatism is a longer recovery time, often up to three months, to achieve corrected vision. Some patients who undergo PRK surgery report seeing a glare or halo in low light that can become a permanent side effect. LASIK and PRK laser eye surgery for astigmatism cost about the same.
Astigmatism is a common eyesight problem that occurs when the cornea develops an elliptical shape instead of a normal sphere. When light enters the eye of a person with astigmatism, it is divided into two areas of focus on the retina in the rear of the eye. People with astigmatism cannot see objects that are far away or close. Although temporary solutions to the condition exist, laser eye surgery for astigmatism may correct the problem permanently, eliminating the need for contact lenses or eyeglasses.
Before doing laser eye surgery, a doctor evaluates the cornea by measuring its thickness and determining how the pupil dilates and how light refracts from the eye. Those who wear gas permeable contact lenses should not use them for several weeks before surgery. If other kinds of contact lenses are worn, they should be avoided for three days before the procedure. Sometimes after surgery, the surgeon places a contact lens bandage on the eye, and the dressing is worn for a few days to allow the cornea to heal.
Some people who undergo LASIK laser eye surgery for astigmatism enjoy improved vision right after the operation, while others need to wear glasses for driving or reading until the cornea completely heals. With PRK surgery, corrected vision may not be possible for up to six months. Potential complications of LASIK and PRK surgery include eye infection, dry eyes, and the possibility that vision becomes less acute after surgery.