Photorefractive keratectomy (PRK) is a laser eye surgery used to ablate the corneal stroma to correct visual refractive errors . PRK was developed in 1983 by Dr. Steven Trokel and colleagues and first performed in 1987 by Dr. Theo Seiler in Berlin. After receiving approval by the US Food and Drug Administration (FDA) in 1996, PRK was briefly the preferred surgical treatment of ametropia as it provided more predictable and stable results than incisional keratotomy. However, the number of PRK procedures fell in the late 1990s with the growing popularity of laser in situ keratomileusis (LASIK).
The study aims to compare the visual and refractive outcomes along with the pain score and patient satisfaction after photorefractive keratectomy in patients who underwent transepithelial or mechanical removal technique
• Age : older than 18 years old .
Gender: Include both males and females.
Stable refraction for at least 12 months .
Intraocular pressure less than 21mmHg.
_ patients with any eye disease (significant cataract or unstable glaucoma )
uncontrolled external disease such as blepharitis, dry eye syndrome, and atopy/allergy.
patients with Keratoconus and other abnormalities of the cornea such as corneal ectasias , thinning , edema , interstitial or neurotrophic keratitis and extensive vascularisation .
Patients with active systemic connective tissue disease such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA)