Biomedical subjects

N Alkara

Publications and source records attributed to N Alkara.

3 recordsLinked to original sources

PubMed2006

[Reoperations after LASIK].

BACKGROUND: Repeat operations after refractive surgery have increased in frequency during the past 10 years. The spectrum of the indications for repeat LASIK may have changed. METHODS: All cases of repeat operations after refractive surgery performed between May 1, 2004 and April 30, 2005 at the Institute of Refractive and Ophthalmic Surgery (IROC) were retrospectively investigated regarding indication for repeat surgery and visual and refractive results. The 1-month results were used to estimate the refractive and visual success rate. RESULTS: Of the 76 reoperations, 69 were performed as re-lifts, 3 eyes had new lamellae cut, and 3 cases needed keratoplasties. The reoperations took place 7.5 +/- 13 months after the primary operation (range 0.5 to 60 months). The most frequent indication was residual astigmatism of 0.5 D and more. Visual loss of more than 1 decimal line did not occur and unaided visual acuity increased from 0.64 to 1.05. No complications were reported, however, 3 eyes needed additional enhancement. CONCLUSIONS: Reoperations after LASIK performed as re-lifts appear to be effective and reasonably safe when using the technique described and respecting a residual stromal thickness of 280 microns.

Comorbidity↗

PubMed1998

[A prospective clinical study of correction of myopic astigmatism by combined treatment with PRK and T-incision and photoastigmatic refractive keratectomy. The results after one year].

BACKGROUND: In contrast to the correction of simple myopia there is no widely accepted technique for the correction of myopic astigmatism. Currently two techniques are available: the photoastigmatic refractive keratectomy (PARK) and the combination of arcuate keratotomies with standard PRK (PRK-T). METHODS: In two groups, 67 patients underwent a correction of myopic astigmatism in a total of 87 eyes (19 by PRK-T and 68 by PARK), and were followed for 1 year. The spherical equivalent was -6.7 D in both groups and the refractive astigmatism ranged from -1.0 to -6.5 D. The PARK procedure was performed by means of an elliptic ablation (Kertom I, Schwind) with a 5.8 x 8.1 mm zone. The PRK-T technique consisted of two arcuate keratotomies with a free optical zone of 7 mm and a standard myopic PRK at least 6 weeks later. RESULTS: The 1 year follow-up was completed in 57 out of 87 eyes included in the study. At 1 year post-operation, 83% of the PRK-T group and 80% of the PARK group had an uncorrected visual acuity of 20/40 or better. The refractive astigmatism was reduced by 76% in the PRK-T group and by 67% in the PARK group. The spherical equivalent was -0.59 +/- 1.1 D at 1 year after PRK-T and -0.28 +/- 1.04 D after PARK. In three eyes of the PARK group (6.7%) a visual loss of more than one Snellen line occurred. Two of these eyes had a preoperative myopia of more than -6 diopters. CONCLUSION: Both techniques have the potential to reduce myopic astigmatism, however, the success rate is not as high compared to spherical PRK. Also, the complication rate of 2.5% in corrections to -6 D is significantly higher than that with spherical myopic PRK.

Adult↗

PubMedDate not supplied

Diametral ablation--a technique to manage decentered photorefractive keratectomy for myopia.

PURPOSE: Decentered ablation after photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) is an intraoperative complication that may significantly influence the visual outcome. Currently, there is no accepted technique available to manage this problem. METHODS: A technique of reoperation for eccentric ablation after PRK called diametral ablation is presented that uses a transepithelial phototherapeutic keratectomy (PTK) that leaves epithelium over the area of primary PRK. This residual epithelium acts as a shield for the previously treated stroma during a second PRK located opposite to the primary PRK with reference to the pupil center. The results of six such retreatments (6 eyes of 6 patients) are presented. RESULTS: In all eyes, a significant improvement regarding centration and subjective complaints was achieved. The eccentricity was reduced from 1.43+/-0.66 mm to 0.36+/-0.15 mm (P = .003). CONCLUSION: Diametral ablation is a promising alternative treatment of eccentric ablation.

Adult↗