With LASIK, your ophthalmologist creates a small flap in the front portion of your cornea by gently separating the tissue. The corneal flap is then folded back.
Once the flap is lifted to one side, laser energy is applied for a few seconds to a minute or so to reshape the cornea. Then, the corneal flap is returned to its original position, where it adheres naturally.
After the procedure, the reshaped cornea focuses light more accurately on the retina.
With PRK, the epithelium, or outer surface layer of your cornea, is removed. An exemer laser, controlled by a computer, is programmed to reshape your cornea. The laser removes tissue, either decreasing the curve of your cornea to correct near-sightedness, or increasing the curve of your cornea, to correct farsightedness.
After the procedure, a contact lens is placed over the cornea to promote healing. The reshaped cornea focuses light more accurately on the retina.
An accommodative lens uses a different technique to allow patients to see better without eyeglasses. These interocular lenses (IOLs) have design features that allow the eye's cilliary muscles to move the IOL either forward or backward in the eye.
This movement of the lens allows the focus to change from near to far or back again, providing good vision up close and far away.
Toric IOLs are monofocal lens implants that have astigmatism correction built into them. Toric IOLs may not completely eliminate the need for eyeglasses.
However, people with astigmatism who have Toric IOLs implanted should have less astigmatism and better vision without glasses than if a traditional IOL was used.
With posterior capsulotomy, converging laser beams are aimed directly at the hazy lens capsule, and as they meet they cut a small hole in the capsule.
This allows light to pass through again, restoring your vision to the way it was not long after your cataract surgery.