LASIK and Refractive Surgery

Intacs are an alternative to laser vision correction procedures. They are used to treat low levels of nearsightedness and astigmatism, but they do not involve the use of a laser to change the shape of the cornea as many other procedures do.

Intacs are clear, micro-thin prescription ring segments that are made of biomedical plastic. They are surgically inserted into the outer portion of the cornea and act to flatten the central part of the cornea.

Unlike laser vision correction procedures, where corneal tissue is actually removed, no tissue is permanently removed with Intacs. If you are not satisfied with your vision after the placement of Intacs, they can be removed and even replaced with a different prescription.

Intacs can also be used to restore vision for people with keratoconus, a corneal disease that involves progressive thinning of the corneal stroma. For many people with keratoconus, the only method previously available to restore functional vision was a cornea transplant. Today, treatment options include Intacs and cornea cross-linking.

LASEK is a procedure that combines some aspects of PRK and LASIK. It is similar to PRK because it is performed on the cornea's surface. However, instead of removing the epithelium (the thin layer of protective skin that covers the cornea) as in PRK, a flap of surface epithelium is loosened with a diluted alcohol solution and moved aside. This creation of a flap is similar to the LASIK procedure, except the flap for LASEK is created on the very outer surface of the cornea. Once the flap is moved aside, the surgeon uses a laser to treat the surface underneath the epithelium. The epithelial flap is then returned to its original position.

LASEK is used to treat nearsightedness, farsightedness and astigmatism, using the same principles as with PRK and LASIK. To treat nearsightedness, the steep cornea is made flatter by removing tissue from the central part of the cornea. This flatter cornea results in moving the point of focus from in front of the retina to directly on the retina.

LASIK is 1 of the most popular vision correction procedures used today. With this procedure, vision is corrected by reshaping the corneal tissue beneath the surface of the eye. A "flap" is created on the corneal surface, which is then flipped back while the surgeon uses a laser to treat, or reshape, the deeper layers of the cornea. The flap is then folded back in place where it bonds without the need for stitches.

Because LASIK is performed under a protective layer of tissue, there is less surface area to heal, less risk of corneal haze, less postoperative discomfort and less need for postoperative medication than with some other procedures. Vision returns rapidly, often within a day or 2.

PRK is another laser vision correction procedure that corrects vision by reshaping the cornea. The difference between PRK and LASIK is in where the laser treatment takes place in the cornea. With LASIK, a flap is created on the surface of the cornea, which is then folded back while the laser treatment is applied to the inner tissue. With PRK, no flap is created.

The outer layer of the cornea, or epithelium, is removed and a laser is applied to the surface of the cornea. Because the epithelium is removed, a contact bandage is placed over the eye during the healing phase. The epithelium grows back very quickly, but you may experience some discomfort, especially during the first few days. Most people resume normal activities within 1-3 days.

SBK is an advanced vision correction procedure. It is similar to LASIK in that a flap is created and the laser treatment is performed underneath this protective layer of tissue. However, the flap for SBK is not nearly as deep as it is for LASIK. The flap is produced just below the Bowman's membrane of the cornea in SBK. This method retains the original thickness of the cornea and reduces the risk of ectasia, a potential complication of LASIK that leads to a thin and bulging cornea.

The benefits of SBK over traditional LASIK include offering a more immediate improvement in vision, decreased treatment time, maintained and possibly increased corneal strength, increased accuracy, and reduced risk of complications.