To assess the incidence of corneal haze following surface ablation in (PRK) in high myopic patients (≥6D). METHODS: In this prospective clinical study, 25 patients with high myopia (≥6D) that is 50 eyes in total, underwent photorefractive keratectomy by Schwind Amaris 500E laser machine. At the initial presentation, each patient underwent a detailed clinical evaluation that included recording of medical history, detailed ocular history, Snellen visual acuity testing, and thorough anterior segment by slit-lamp bio-microscopy and posterior segment examination with indirect ophthalmoscopy were done. Corneal topography and pachymetry were also done. The patient is followed up at 1week to observe for re-epithelialization and then at 1, 3 and 6 months for observation of haze under slit-lamp examinamination. RESULTS: In our study of 25 patients, that is 50 eyes in total were divided into 3 groups depending upon the spherical equivalence. Group 1 between 6.00-7.00D, group 2 between 7.00-8.00D, and in group 3 more than 8D (≥8.00D). Over 6months period of follow up a significant haze was noted as the patient’s refractive error increased. Out of 50 eyes, 11 eyes (84.6%) with spherical equivalence of 6.00-7.00D (group 1) had grade 0, 8 eyes (66.6%) with spherical equivalence of 7.00-8.00D (group 2) had grade 0, and 6 eyes (24%) with spherical equivalence ≥8.00D (group 3) had grade 0. Thus, the results show that there has been a significant decrease in the eyes with no corneal haze as the refractive error increased. Eyes with grade 1 haze in group1 were 2 (15.3%), group 2 were 3 (25%), and group 3 were 7 (28%). These results showed that the incidence of grade 1 haze increased with increase in spherical equivalence. Eyes with grade 2 haze in group 1 were 0 (0%), group 2 were 1 (8.3%), group 3 were 10 (40%). Thus, it is seen that grade 2 haze was not noted in eyes with spherical equivalence between 6.00-7.00D, but were noted with increase in the refractive error. Eyes with grade 3 haze in group 1 and 2 were 0, and group 3 were 2 (8%). Thus, the results show that as the refractive error of increases the incidence of haze and the degree of haze increases. The p value 6D), thus compromising the post-operative visual acuity. 2. With the use of intra-operative 0.02% Mitomycin-C (MMC) and post-operative topical corticosteroids, thus modifying the healing process and decreasing the incidence of haze in high myopic patients. 3. Thus, concluding that PRK can be an effective procedure in treating high myopic patient.
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