Valley Eye Care

... is a surgical procedure designed to correct low degrees of nearsightedness. A fine diamond-bladed instrument is used to make 8 tiny radial incisions almost to the edge of the cornea from outside the visual zone. These small cuts are made up to 90% of the corneal thickness without going all the way through. The cuts weaken the outside area of the cornea allowing it to bulge slightly thereby changing the shape at the center. The flattening of the center reduces the nearsightedness. If the desired amount of change is not accomplished, the incisions may be deepened and lengthened in a second procedure called an enhancement. RK is not as predictable for higher amounts of refractive error and may not be stable over several years.

... is a variation of radial keratotomy used to treat low to moderate amounts of astigmatism. The surgeon makes crosswise cuts in areas of the cornea that have more curvature. The cross cuts serve to flatten only one aspect or meridian of the cornea. This procedure may not be as predictable as R K.

... uses the excimer laser's non-thermal light energy to reshape the front surface of the eye. Before the laser is applied the protective surface layer of the cornea, the epithelium, is carefully scraped away. The laser is then used to vaporize several microns of the underlying tissue. When the treatment is completed, a bandage soft contact lens is worn for 3 or 4 days while the epithelium regrows over the treated area. Repeat procedures, or enhancement, can be performed here as well, but are not required as often.

... is a treatment being used by an increasing number of surgeons to correct all ranges of vision problems but is particularly useful in the higher amounts of refractive error. This procedure uses a precise motorized instrument called a microkeratome to create a flap of tissue in the center of the cornea. The flap is lifted out of the way and the laser then reshapes the underlying tissue. After the laser is used, the flap is replaced and adheres without the need for sutures. With this procedure, discomfort is reduced and short term healing tends to be quicker. No bandage contact lens is required. Enhancements are also possible.
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Eyes on the Future Some of the newest technologies to improve your vision
INTACS (Approved April 1999)	INTRAOCULAR LENSES	CUSTOM LASIK
Crescent-shaped rings placed within the cornea FIXES Low levels of nearsightedness, without astigmatism or with mild astigmatism ADVANTAGES Removable, leaves cornea intact DISADVANTAGES Can't correct farsightedness or high degrees of nearsightedness or astigmatism COST $2,000 to $2,500	Lens implanted either behind cornea or behind the iris FIXES Particularly effective for high degrees of near- and farsightedness ADVANTAGES Removable and leaves cornea intact DISADVANTAGES may lead to corneal injury, cataracts and intraocular infection COST Still under study in the U.S.	LASIK tailored to individual differences in cornea, lens and retina FIXES Near- and far-sightedness, with or without asigmatism ADVANTAGES Correction to maximum visual acuity, in some cases to 20/10 (6/3 in metric) DISADVANTAGES Permanent change of corneal curvature COST Not yet available

In LTK, the doctor uses a laser to heat a series of small, dot-shaped areas of the cornea. This causes the corneal tissue to expand and the curvature of the cornea steepens. LTK is used to treat people who are farsighted.

Candidates for LTK should be at least 18 years old, have stable vision and no abnormalities of the cornea or external eye.

Ortho-K is a non-surgical procedure that involves the wearing of a series of specially designed rigid contact lenses to progressively reshape the curvature of the cornea over time. The results of the painless procedure are not permanent; thus, retainer contact lenses must be worn periodically to maintain improvements made in vision. Ortho-K is used to treat low to moderate nearsightedness and low degrees of astigmatism.