Biomedical subjects

R Aktunç

Publications and source records attributed to R Aktunç.

5 recordsLinked to original sources

PubMed1998

Laser in situ keratomileusis after photorefractive keratectomy for myopic regression.

PURPOSE: To assess the efficacy and safety of laser in situ keratomileusis (LASIK) for regression after excimer laser photorefractive keratectomy (PRK). SETTING: Eye Research Center, Istanbul University, Istanbul, Turkey. METHODS: Laser in situ keratomileusis to treat residual myopia ranging from 1.50 to 12.50 diopters (D) (mean 5.96 D +/- 3.06 [SD]) was performed in 45 eyes of 25 patients. Cylindrical corrections were done in 7 eyes (15.6%) and spherical ablations, in 38 (84.4%). The mean interval between primary PRK and LASIK retreatment was 18.50 +/- 8.12 months. The procedure was performed under a hinged corneal flap using the Chiron Automated Corneal Shaper and Chiron Keracor 116 excimer laser. RESULTS: Six months after LASIK retreatment, mean spherical equivalent refraction was -0.67 +/- 0.77 D. Thirty-six eyes (80%) were within +/- 1.00 D of emmetropia. Uncorrected visual acuity was 20/40 or more in 31 eyes (68.9%); 2 eyes (4%) lost 2 lines of best spectacle-corrected visual acuity. There was no statistically significant difference in corneal haze before and after LASIK. CONCLUSION: Laser in situ keratomileusis was safe and effective for treating residual myopia after excimer laser PRK.

Adult↗

PubMed1998

The effects of topical steroids on refractive outcome and corneal haze, thickness, and curvature after photorefractive keratectomy with a 6.0-mm ablation diameter.

BACKGROUND AND OBJECTIVE: To study the effect of topical prednisolone acetate after photorefractive keratectomy (PRK) using a 6.0-mm ablation diameter on the refractive and visual outcomes, corneal haze, corneal thickness, and corneal curvature in a prospective, double-masked, randomized manner. PATIENTS AND METHODS: Seventy-two eyes of 36 patients who had excimer laser PRK for correction of myopia ranging from -3.00 to -6.00 D (-4.11 +/- 0.84 D in eyes treated with steroids and -4.38 +/- 0.79 D in eyes treated with placebo; mean +/- SD) were enrolled. PRK procedures were performed using a 193-nm argon-fluoride excimer laser with 180-ml/cm2 fluence, a 10-Hz repetition rate, and a 6.0-mm ablation diameter. One eye of each patient was treated with the steroid (prednisolone acetate) and the other eye with placebo. Patients were observed for at least 12 months after PRK. RESULTS: There was no statistically significant difference between the steroid and the placebo groups with regard to refraction measurements that were taken postoperatively at 3 months (P = .39) and 12 months (P = .51). The corneas showed an increase in thickness after PRK in both groups, but the difference was not statistically significant at 12 months postoperatively (P = .45). The corneal haze score was not statistically different at any stage between groups (P = .30 at 3 months, P = .84 at 12 months). Keratometric data derived from corneal topography did not show any statistically significant difference (P = .85 at 3 months, P = .96 at 12 months). The rate of uncorrected visual acuity of 20/40 or more was 79.4% (27 eyes) in the steroid group and 70.5% (24 eyes) in the placebo group (P = .40). The rate of loss of 2 or more lines in best spectacle-corrected visual acuity was 5.85% (2 eyes) in the steroid group and 8.8% (3 eyes) in the placebo group (P = 1.0). CONCLUSION: Topical prednisolone acetate use for 3 months after PRK with a 6.0-mm ablation diameter has no effect on refractive and visual outcome, corneal haze, corneal thickness, and corneal curvature.

Administration, Topical↗

PubMed1996

Centration of excimer laser photorefractive keratectomy and changes in astigmatism.

One of the most important factors that influence the success of PRK might be corneal centration during treatment. We evaluated our centration rate in 49 eyes by using computer-assisted corneal topography. Only single zone treated eyes were chosen for the analysis and 91.5% of the eyes were centered within a 1 mm treatment zone while 51% were within 0.5 mm. At the end of the follow-up time of 10.4 months, these centration zones were found to have no influence on the attempted spherical refractive outcome, whereas increasing decentration induced an increase in postoperative astigmatism.

Adult↗

PubMed1996

Double zone PRK for high myopia.

INTRODUCTION: Although excimer laser PRK is our operation of choice for treating myopia, the correction of myopia exceeding -8.00 dpt is still a challenge as this procedure requires a deeper keratectomy. Therefore a double zone treatment may be beneficial to reduce ablation depth. METHODS: Twenty-one eyes with myopia between -8.00 dpt and -14.00 dpt were included in this study. Twelve eyes were treated 60% of myopia by 5 mm zone and the remaining 40% in a 4 mm zone in the same session (Group 1). RESULTS: Nine eyes achieved 60% of the desired correction treated with a 4 mm zone whereas 40% correction was achieved in a 5 mm zone (Group 2). No significant difference in postoperative healing, pain, hyperopic shift, myopic regression and haze was observed at the end of the mean follow-up time (10.4 months) but photophobic complaints were less in Group 2. Best corrected visual acuity did not decrease significantly. CONCLUSIONS: Double zone treatment seems to be an interesting method for treating moderate to high myopia.

Adult↗

PubMedDate not supplied

Simultaneous and sequential photorefractive keratectomy.

The purpose of this study was to show the safety, effectiveness, and predictability of simultaneous bilateral as compared to sequential unilateral photorefractive keratectomy in 273 normally sighted myopic eyes. An excimer laser with a fluence of 180 mj/cm2 at a frequency of 10 Hz was used at three ablation zones (5 mm, 6 mm, and 6.5 mm). There were no significant differences between the two groups' results. Mean refraction at six months was 0.34-0.96 D in group 1 simultaneous group and 0.32-0.95 D in group 2 sequential group. At 9 months after surgery, 84% of eyes had an uncorrected visual acuity of at least 20/40. The average pain score on the first postoperative day was 2.4 for group 1 simultaneous group and 2.3 for group 2 sequential group. No serious complications occurred. Despite the short follow up, simultaneous bilateral photorefractive keratectomy appears to be an effective and safe procedure for the correction of myopia.

Adult↗