OBrart, DPS and Corbett, MC and Verma, S and Heacock, G and Oliver, KM and Lohmann, CP and Muir, MGK and Marshall, J (1996) Effects of ablation diameter, depth, and edge contour on the outcome of photorefractive keratectomy. JOURNAL OF REFRACTIVE SURGERY, 12 (1). pp. 50-60. ISSN ,
Full text not available from this repository.Abstract
PURPOSE: To investigate the effects of the ablation diameter, depth, and edge contour on the outcome of excimer laser photorefractive keratectomy (PRK). METHODS: A prospective study was conducted in which 60 patients (60 eyes) were randomly allocated to 5.00-mm, 6.00-mm, or 5.00 to 6.00-mm multizone treatment groups. All eyes underwent a -6.00 diopter (D) correction using a Summit Omnimed excimer laser. RESULTS: In eyes treated with 6.00-mm diameter zones, the initial hyperopic shift was reduced, with significant differences at 1 and 4 weeks (p<0.01). At 6 and 12 months, the refractive changes were closer to the intended correction with 6.00-mm diameters. The predictability of PRK was improved with 6.00-mm zones, with a significant reduction in variance of the refractive changes, at all stages postoperatively (p<0.05 to p<0.001). Objective measurements of haze were significantly less at 1, 3, and 6 months with 6.00-mm ablations (p<0.05). There were no differences between the 5.00-mm and the 5.00- to 6.00-mm multizone groups. Computerized measurements of ''night'' halo were significantly smaller in the 6.00-mm treatment group at 1 week and 1 month (p<0.05). At 12 months, two patients treated with 5.00-mm zones and three with the 5.00- to 6.00-mm multizone complained of severe night vision disturbances. No 6.00-mm eyes were similarly affected. CONCLUSIONS: Treatment with a 6.00-mm spherical ablation diameter produced less initial overcorrection, improved predictability, and was associated with a reduction in postoperative halos and night vision disturbances. Creating a superficial blend zone with a 5.00- to 6.00-mm multizone treatment had no beneficial effect on the outcome.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | EXCIMER-LASER; SIGHTED EYES; FOLLOW-UP; MYOPIA; KERATOMILEUSIS; SURGERY; CORNEA; |
| Depositing User: | Dr. Gernot Deinzer |
| Last Modified: | 19 Oct 2022 08:36 |
| URI: | https://pred.uni-regensburg.de/id/eprint/52086 |
Actions (login required)
 |
View Item |
