Laser Vision Center
Laser vision correction is one of the most exciting medical advancements in the past two decades. In the past, refractive errors (far-sightedness, near-sightedness, and astigmatism) can only be corrected with glasses or contact lenses. By using the excimer laser to reshape the front surface of the cornea, ophthalmologists now can correct refractive errors permanently. There are two types of laser vision correction: LASIK and PRK.
LASIK corrects for near- and far-sightedness and astigmatism by modifying the shape or corneal surface. LASIK is an acronym for laser-assisted in-situ keratomileusis. LASIK has been very popular in recent years; millions have been performed in the United States and worldwide.
Like many eye operations, successful outcome requires meticulously preoperative examination and workup. Prior to LASIK:
- Contact lens patients are asked to stay out of contact lenses for two to four weeks prior to LASIK evaluation. This is crucial because all contact lenses have the potential to distort the shape of the cornea to some extent. Extended-wear soft contact lenses, rigid gas-permeable and hard contact lenses tend to cause more corneal distortion than daily wear soft-contact lenses. Staying out of contact lenses for two to four weeks gives cornea time to regain its natural shape.
- Detailed full eye examination to show that the eye is healthy.
- The glass prescription is carefully checked and must be stable for at least six months.
- If dry eye is present, it must be addressed prior to LASIK. Dry eye can be treated with artificial tears, punctal plugs, and Restasis, depending on the severity of dry eye.
- Corneal topography measures the corneal thickness and the curvature of the front and back surfaces of the cornea. Corneal topopraphy is essential in making sure that patient’s cornea is suitable for LASIK. Cornea must have proper contour and adequate thickness.
- If patient has abnormal distortion for the cornea (such as keratoconus or pellucid corneal degeneration), then she is not a LASIK candidate.
- If the patient’s cornea is too thin, she is not a LASIK candidate, because there may not be enough corneal tissue left after LASIK to ensure long-term stability of the corneal architecture.
- Generally speaking, there should be no significant cataracts, macular degeneration or other retinal pathology, which could compromise visual outcome.
Patient counseling is imperative in LASIK. The surgeon must understand patient’s motivation for LASIK. The patients are warned about the possibility of dry eye and seeing halos at night; both are frequent, usually temporary, occurrences after LASIK. Certain occupations could be relative contraindications for LASIK such as piloting airplanes or extended night driving. Patient are counseled that in about 10% of patients will need a second LASIK or PRK procedure (also known as enhancement) to reduce residual refractive error that might remain after the initial LASIK. Prior to undergoing LASIK, patient has to understand that laser vision correction is a staged process.