Vision Correction Options

• LASIK (laser in-situ keratomileusis)
• SBK (Sub-Bowman’s Keratomileusis)
• PRK (Photo-Refractive Keratectomy)
• LASEK (Laser Epithelial Keratomileusis) or Advanced Surface Ablation (ASA)
• Intacs (Corneal Ring Segments)
• Intacs for Keratoconus

LASIK (laser in-situ keratomileusis)

LASIK is one 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.

The benefits of LASIK, because it is performed under a protective layer of tissue, are that 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 two.

To treat nearsightdness, 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.

To treat farsightedness, the flat cornea is made steeper by removing tissue from the outer portion of the cornea. This results in moving the point of focus from behind the retina to directly on the retina.

To treat astigmatism, the cornea is made more spherical, or more like a basketball than a football. This results in light rays coming to one point of focus on the retina rather than multiple points. Astigmatism can be treated at the same time as nearsightedness and farsightedness.

SBK (Sub-Bowman’s Keratomileusis)

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 which 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.

In SBK, the cornea is treated using the same principles as in LASIK:
To treat nearsightdness, 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.

To treat farsightedness, the flat cornea is made steeper by removing tissue from the outer portion of the cornea. This results in moving the point of focus from behind the retina to directly on the retina.

To treat astigmatism, the cornea is made more spherical, or more like a basketball than a football. This results in light rays coming to one point of focus on the retina rather than multiple points. Astigmatism can be treated at the same time as nearsightedness and farsightedness.

LASIK or SBK may be appropriate for you if:

• You want to reduce or eliminate the need for glasses or contacts.
• You are an adult (at least age 18 or older).
• You have had a stable eye prescription for at least one year.
• You have mild to moderate nearsightedness, farsightedness, and/or astigmatism.
• You do not have any health issues affecting your eye.
• You do not have signs of glaucoma or cataracts.

PRK (Photo-Refractive Keratectomy)

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 epilthelium is removed, a contact bandage is placed over the eye during the healing phase. The epilthelium grows back very quickly, but you may experience some discomfort, especially during the first few days. Most patients resume normal activities within one to three days.

In PRK, the cornea is treated using the same principles as in LASIK:
To treat nearsightdness, 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.

To treat farsightedness, the flat cornea is made steeper by removing tissue from the outer portion of the cornea. This results in moving the point of focus from behind the retina to directly on the retina.

To treat astigmatism, the cornea is made more spherical, or more like a basketball than a football. This results in light rays coming to one point of focus on the retina rather than multiple points. Astigmatism can be treated at the same time as nearsightedness and farsightedness.

PRK may be appropriate for you if:

• You want to reduce or eliminate the need for glasses or contacts.
• You are an adult (at least age 18 or older).
• You have had a stable prescription for at least one year.
• You have low to high levels of nearsightedness, farsightedness, and/or astigmatism.
• You have no health issues affecting your eyes.
• You have corneas too thin for LASIK.
• You have large pupils.

LASEK (Laser Epithelial Keratomileusis) or
Advanced Surface Ablation (ASA)

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 can be used to treat nearsightedness, farsightedness, and astigmatism, using the same principles as with PRK and LASIK:
To treat nearsightdness, 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.

To treat farsightedness, the flat cornea is made steeper by removing tissue from the outer portion of the cornea. This results in moving the point of focus from behind the retina to directly on the retina.

To treat astigmatism, the cornea is made more spherical, or more like a basketball than a football. This results in light rays coming to one point of focus on the retina rather than multiple points. Astigmatism can be treated at the same time as nearsightedness and farsightedness.

LASEK may be appropriate for you if:

• You want to reduce or eliminate the need for glasses or contacts.
• You are at least 18 years old.
• You have had a stable eyeglass prescription for at least one year.
• You do not have any health issues that affect your eyes.
• You have wide pupils.
• You have corneas too thin for LASIK.

Intacs (Corneal Ring Segments)

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 may be removed and even replaced with a different prescription.

Intacs may be appropriate for you if:

• You want to reduce or eliminate the need for glasses or contacts.
• You are at least 21 years old.
• You have mild nearsightedness and/or astigmatism.
• You have had a stable eyeglass prescription for at least one year.
• You do not have any health issues that affect your eyes.

Intacs for Keratoconus

Keratoconus is a corneal disease that involves progressive thinning of the corneal stroma. It frequently affects both eyes, often with one eye being more involved than the other. As the disease progresses and the cornea grows thinner, it begins to bulge forward in shape of a cone, resulting in distorted and blurry vision. It often becomes difficult to properly fit these patients with contact lenses or to correct their vision with eyeglasses. For many patients with keratoconus, the only method previously available to restore functional vision was a corneal transplant.

INTACS may provide another alternative to this subset of patients. 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 may be removed and even replaced with a different prescription.

INTACS used for the treatment of nearsightedness and astigmatism associated with keratoconus is approved by the FDA as a Humanitarian Use Device. This means that, while INTACS are FDA approved for the treatment of those with general nearsightedness or astigmatism, their effectiveness has not been proven for the treatment of nearsightedness and astigmatism associated with keratoconus.

The FDA-approved indication for INTACS for those with keratoconus is with this subset of patients:

• Those who have experienced a progressive deterioration in their vision, such that they can no longer achieve functional vision on a daily basis with their contact lenses or eyeglasses.
• Those who are 21 years of age or older.
• Those who have clear central corneas.
• Those who have a corneal thickness of 450 microns or greater at the proposed incision site.
• Those who have corneal transplantation as the only remaining option to improve their functional vision.

For more information about INTACS, visit www.intacsforkeratoconus.com or contact our refractive surgery coordinator at (913) 945-6700.

For more information about keratoconus, visit the National Keratoconus Foundation at www.nkcf.org