Comparison of corneal centering in photorefractive keratectomy

Corneal ectasia after photorefractive keratectomy.

Two patients developed corneal ectasia after photorefractive keratectomy (PRK). Case 1 had evidence of early keratoconus preoperatively, with manifest refractions of -4.00 +2.50 x 160 (20/20) in the right eye and -7.00 +3.00 x 180 (20/30) in the left eye; thin corneas (472 microm and 441 microm, respectively); and inferior paracentral steepening in the right eye and central steepening in the le...

Photorefractive keratectomy: implications of corneal wound healing.

Photorefractive keratectomy: implications of corneal wound healing

Photorefractive keratectomy (PRK) with an argon fluoride laser (193 nm) was developed to alter the refractive power of the eye predictably and permanently. At PRK the central corneal epithelium is debrided mechanically and a disc 4 to 6 mm in diameter is ablated into the anterior stroma using computer controlled algorithms to control the depth of the wound. Theoretically for corrections of up t...

Corneal epithelial recovery following photorefractive keratectomy.

AIMS To further understand the morphological and functional recovery of corneal epithelium following excimer laser photorefractive keratectomy (PRK). METHODS The right eyes (group 1) of 15 male, New Zealand white rabbits weighing 2-3 kg underwent PRK. The left eye of each rabbit (group 2) underwent simple mechanical de-epithelialisation and were examined as treated controls. Both eyes of anot...

Corneal Regeneration After Photorefractive Keratectomy: A Review.

Photorefractive keratectomy (PRK) remodels corneal stroma to compensate refractive errors. The removal of epithelium and the ablation of stroma provoke the disruption of corneal nerves and a release of several peptides from tears, epithelium, stroma and nerves. A myriad of cytokines, growth factors, and matrix metalloproteases participate in the process of corneal wound healing. Their balance w...