If it turn out that you are not a good candidate for LASIK or PRK, you and your eye doctor may wish to consider other surgical options.
Intacs Corneal Ring Segments
Insertion of Intacs corneal ring segments was formerly offered to patients with mild myopia and minimal astigmatism as another option for correcting their nearsightedness. Small, thin arcs of plastic are inserted into the peripheral part of the cornea. Each arc looks like a half circle. These ring segments reshape the eye, correcting mild levels of nearsightedness. Intacs corneal ring segments are no longer used to correct myopia, because the results are less accurate than LASIK and the ring segments cannot correct astigmatism. Today, the ring segments are primarily used to treat keratoconus and ectasia.
Astigmatic keratotomy (AK) corrects only astigmatism. Usually, 1 or 2 incisions are made in the peripheral cornea to make it rounder (as if loosening the laces of a football). This procedure has a long track record but is rarely used today by itself, because it is significantly less accurate that PRK and LASIK for correcting astigmatism.
The most frequent use of AK today is for the correction of astigmatism at the time of lens implant surgery (either cataract or refractive lens exchange surgery). AK also goes by the name “relaxing incisions”.