Davidorf Eye Group - Los Angeles Lasik Eye Surgery

IOLs are intraocular lenses or artificial lenses. They replace the eye’s natural lens.

In past years IOLs were monofocal. That meant that one eye received an IOL set for near distance, and the other eye was left naturally farsighted. (It could also be the other way around.) The brain then adapted to seeing with one eye at a time.

More recently, multifocal and accommodative IOLs have been developed. A multifocal IOL has steps or zones in its construction which give clear vision at predetermined distances. Together they cover the near-to-far spectrum.

An accommodative IOL mimics the eye’s natural ability to change focus instantly as it moves from a near object to a far one. Without the natural lens in the eye, that ability is lost. An accommodative IOL restores it by having tiny hinges. The eye surgeon attaches these hinges to the muscles which used to control the lens. Those muscles control the IOL, and to the person with the IOL, vision is working much as it used to.

So in their different ways, both multifocal and accommodating IOLs allow clear vision at more than one distance, eliminating the need for contacts or glasses.

PRK (Photorefractive Keratectomy) is a vision correction procedure that does not create any corneal flap. Instead it removes some surface tissue of the cornea (epithelium) by gentle scraping. This tissue is then discarded. The exposed layer beneath the surface is now ready for laser treatment.

The rest of the procedure is similar to LASIK. The only difference is that since there is no flap to replace, the corneal surface must regenerate itself. This makes for a longer recovery period.

LASEK (Laser Epithelial Keratomileusis) is a laser eye surgery procedure that held promise as a hybrid of PRK (Photorefractive Keratectomy) and LASIK (Laser-Assisted in Situ Keratomileusis).

Rather than creating a corneal flap with a microkeratome (as done in LASIK) or completely removing some of the patient’s epithelium (as in PRK), LASEK uses alcohol to loosen the cell bonds and a very fine blade known as a trephine to separate a thin flap of surface tissue. It is then rolled back, the laser treatment done, and the flap replaced over the treated tissue. From the patient’s perspective, LASEK is essentially indistinguishable from PRK, although the immediate postoperative vision tends to be better with PRK.

CK (Conductive Keratoplasty) is a vision correction technique that uses radio-frequency (RF) energy instead of a laser to reshape the cornea. The doctor uses a special probe to direct the RF energy to the cornea.

To correct farsightedness, the surgeon directs RF to the corneal periphery, which shrinks the corneal fibers, making them act like a purse-string or belt. It tightens, making the corneal center grow steeper.

To correct nearsightedness, the surgeon directs RF to the corneal center, shrinking those fibers instead of the peripheral ones. This flattens the cornea.

CK is basically a painless process that takes only about 5 minutes. The major advantage is that it is extremely safe. It has the fewest side effects and the lowest level of complications compared to other vision correction procedures. For this reason, CK has been approved by the Federal Aviation Administration (FAA) for use on pilots.