Background
The surgical reduction of hyperopia is an evasive but worthy pursuit since hyperopia affects both distance vision and near vision and is compounded by presbyopia at a time when patients are in the prime of their vocational and personal life. A wide spectrum of refractive surgeries has been applied over the years in the relentless pursuit of hyperopia correction.
With the introduction of the excimer laser, the possibilities of carving a positive lenticule into the cornea were investigated.
To steepen an untreated corneal center, it is necessary to have a relatively deep peripheral ablation, with a progressive steepening of the transition of zone 1.
See the image below.
Corneal topography with central uniform steepening following hyperopic LASIK.
The argon fluoride 193-nm excimer laser corrects refractive errors by sub–micron-precision tissue removal from the cornea.
Photorefractive keratectomy (PRK) has been used successfully for hyperopia but has problems of regression, induced astigmatism, and corneal haze, thereby limiting its usefulness to the correction of mild hyperopia only.
Excimer laser in situ keratomileusis (LASIK) overcomes many disadvantages of surface ablation (PRK) and has become the procedure of choice for treating hyperopia up to +6.00 diopters (D).
See related CME at Highlights of the American Society of Cataract and Refractive Surgery Symposium.