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A Randomized Comparison of Pupil-Centered Versus Vertex-Centered Ablation in LASIK Correction of Hyperopia

      Purpose

      To compare visual and optical outcomes of pupil-centered vs vertex-centered ablation in patients undergoing laser-assisted in situ keratomileusis (LASIK) for hyperopia.

      Design

      Randomized, double-masked, prospective, single-center trial.

      Methods

      Setting: Institutional practice. Study population: Sixty eyes of 30 patients with low and moderate hyperopia. Intervention procedure: Eyes underwent LASIK (Allegretto excimer laser). In 30 eyes, the ablation was centered on the pupil, while in the 30 other eyes the ablation was centered on the corneal reflex. Main outcome measures: Primary outcome measure was the safety index. Main secondary outcome measures were efficacy index, manifest refraction, uncorrected visual acuity, best spectacle-corrected visual acuity (BCVA), and ocular high-order aberrations for a 6-mm pupil size.

      Results

      At 3 months postoperatively, the safety index was 0.99 ± 0.04 in the pupil-centered group and 0.99 ± 0.08 in the vertex-centered group (P = .97). The efficacy index was also similar for both groups: 0.96 ± 0.05 in pupil-centered eyes and 0.93 ± 0.09 in vertex-centered eyes (P = .31). Optical aberrations were similar for pupil-centered and vertex-centered eyes. Considering only eyes showing large pupil decentration, we found a tendency for better visual results in favor of pupil-centered eyes in terms of safety index and a slight but significant increase of coma in vertex-centered eyes.

      Conclusion

      LASIK is an effective procedure for treatment of hyperopia. Pupil-centered and vertex-centered treatments provide similar visual and optical outcomes. However, in eyes showing large temporal pupil decentration, pupil-centered ablation seemed to produce a lower amount of coma and, as a consequence, a reduced loss of BCVA compared with vertex-centered patients.
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      Biography

      Vincent Soler, MD, MS, is an Associate Professor in the Ophthalmology Department of Purpan Hospital, Toulouse, France. His primary clinical interests are corneal surgery, glaucoma and pediatric ophthalmolgy. He is also involved in myopia genetics research.

      Linked Article

      • A Randomized Comparison of Pupil-Centered Versus Vertex-Centered Ablation in LASIK Correction of Hyperopia
        American Journal of OphthalmologyVol. 153Issue 4
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          We read with interest the article by Soler and associates comparing pupil-centered vs vertex-centered ablations for the correction of hyperopia.1 From analysis of the ocular aberrations, they found that in eyes showing large pupil decentration (distance from pupil center to corneal vertex more than 0.25 mm), pupil-centered ablation seemed to induce a lower amount of coma and, consequently, a reduced loss of corrected distance visual acuity compared with vertex-centered patients.1 Interestingly, in the group with lower pupil decentration, they found better aberrometric outcomes when centered on the corneal vertex.
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