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Hofmeister E.M.,Naval Medical Center San Diego | Bishop F.M.,Naval Medical Center San Diego | Kaupp S.E.,Naval Medical Center San Diego | Schallhorn S.C.,Optical Express
Journal of Cataract and Refractive Surgery | Year: 2013

Purpose: To evaluate the safety and efficacy of mitomycin-C (MMC) 0.01% (0.1 mg/mL) in preventing haze formation after wavefront-guided photorefractive keratectomy (PRK) for higher myopia at 3 exposures. Setting: United States Navy Refractive Surgery Center, San Diego, California, USA. Design: Double-masked randomized prospective trial. Methods: Sixty-, 30-, and 15-second exposures of MMC 0.01% were compared in wavefront-guided PRK for higher myopia. One eye received MMC (surgical sponge) and the other a placebo. All eyes received a 4-month tapering postoperative topical steroid regimen. Endothelial cell densities, haze scores, high- and low-contrast acuities, and manifest refraction were measured preoperatively and 1, 3, 6, and 12 months postoperatively. Outcomes were analyzed as repeated measures over time. Results: The mean preoperative manifest refraction spherical equivalent was -5.98 diopters (D) (range -4.4 to -8.0 D). No eye developed more than trace haze. There was a significant difference in haze scores between MMC-treated eyes and untreated eyes at 1 and 3 months (P=.034) but no difference at 6 and 12 months. Endothelial cell densities decreased in the treated eyes and untreated eyes at all 3 exposures at 1 month but returned to baseline by 6 months. There was no difference in acuities or refractions with or without MMC. Conclusions: Mitomycin-C may not be needed to prevent haze after modern PRK with a 4-month steroid taper. There was no clinically significant difference in haze formation between MMC eyes and control eyes at the concentration and exposures used. Financial Disclosure: Dr. Schallhorn is a consultant to Abbott Medical Optics, Inc. No author has a financial or proprietary interest in any material or method mentioned. © 2013 ASCRS and ESCRS Published by Elsevier Inc. Source

Schallhorn S.,Optical Express | Tanzer D.,U.S. Navy | Sanders D.R.,Center for Clinical Research | Sanders M.,Center for Clinical Research | And 2 more authors.
Journal of Refractive Surgery | Year: 2010

PURPOSE: To compare changes in simulated night driving performance after Visian Toric Implantable Collamer Lens (TICL; STAAR Surgical) implantation and photorefractive keratectomy (PRK) for the correction of moderate to high myopic astigmatism. METHODS: This prospective, randomized study consisted of 43 eyes implanted with the TICL (20 bilateral cases) and 45 eyes receiving conventional PRK (VISX Star S3 excimer laser) with mitomycin C (22 bilateral cases) for moderate to high myopia (-6.00 to -20.00 diopters[D] sphere) measured at the spectacle plane and 1.00 to 4.00 D of astigmatism. As a substudy, 27 eyes of 14 TICL patients and 41 eyes of 21 PRK patients underwent a simulated night driving test. The detection and identification distances of road signs and hazards with the Night Driving Simulator (Vision Sciences Research Corp) were measured with and without a glare source before and 6 months after each procedure. RESULTS: No significant difference was noted in the pre- to postoperative Night Driving Simulator in detection distances with and without the glare source between the TICL and PRK groups. The differences in identification distances without glare were significantly better for business and traffic road signs and pedestrian hazards in the TICL group relative to the PRK group whereas with glare, only the pedestrian hazards were significantly better. A clinically relevant change of Night Driving Simulator performance (>0.5 seconds change in ability to identify tasks postoperatively) was significantly better in the TICL group (with and without glare) for all identification tasks. CONCLUSIONS: The TICL performed better than conventional PRK in the pre- to postoperative Night Driving Simulator testing with and without a glare source present. Copyright © SLACK Incorporated. Source

Venter J.,Optical Express | Pelouskova M.,Optical Express
Journal of Cataract and Refractive Surgery | Year: 2013

Purpose: To evaluate the refractive outcomes and rotational stability after implantation of a multifocal toric intraocular lens (IOL) with a surface-embedded near section. Setting: Private center, London, United Kingdom. Design: Case series. Methods: This study evaluated eyes with more than 1.50 diopters (D) of preexisting corneal astigmatism. After phacoemulsification, Lentis Mplus toric IOLs were implanted in all cases. The main outcome measures were refraction, uncorrected (UDVA) and corrected (CDVA) distance visual acuities, uncorrected near visual acuity (UNVA), keratometry, and IOL position. Three-month postoperative data are presented. Results: The study enrolled 89 eyes (58 patients). The mean monocular postoperative UDVA and UNVA were 0.03 logMAR ± 0.11 (SD) and 0.17 ± 0.14 logMAR, respectively. The mean refractive cylinder decreased from 2.90 ± 1.31 D preoperatively to 0.50 ± 0.39 D postoperatively (P<.001). The mean difference between the planned axis of implantation and the actual axis postoperatively was 2.53 ± 2.27 degrees. Conclusion: The multifocal toric IOL with a surface-embedded near section effectively corrected preexisting corneal astigmatism. The IOL was stable in the capsular bag, there were no visually significant complications, and there was no significant rotation out to 3 months postoperatively. Financial Disclosure: Neither author has a financial or proprietary interest in any material or method mentioned. © 2013 ASCRS and ESCRS. Source

Schallhorn S.,University of California at San Francisco | Brown M.,Optical Express | Venter J.,Optical Express | Hettinger K.,Optical Express | Hannan S.,Optical Express
Journal of Refractive Surgery | Year: 2014

PURPOSE: To determine the relationship between lowlight pupil size and patient-reported outcomes 1 month after wavefront-guided LASIK in young patients with myopia. METHODS: Retrospective case series of 10,944 eyes of 5,563 young patients with myopia who underwent wavefront-guided LASIK (6.0-mm optical zone). Preoperative pupil size was measured under low-light conditions with an infrared pupillometer. Visual and refractive outcomes were evaluated at 1 month postoperatively. A questionnaire was administered to assess patient-reported outcomes including satisfaction with the procedure, night driving, and glare and halo visual symptoms. RESULTS: The average patient age was 29.8 years (range: 18 to 40 years). The mean preoperative manifest spherical equivalent of -3.49 diopters (D) (range: -0.50 to -11.75 D) was reduced to -0.04 ± 0.29 D at 1 month, with 94% of eyes achieving an uncorrected distance visual acuity of 20/20 or better. The mean lowlight pupil diameter was 6.6 mm (range: 4 to 9 mm) and 1,514 patients (27.2%) had a diameter of 8 mm or larger. No correlation between pupil diameter and patient-reported outcomes was found (r range: -0.02 to 0.07). Logistic regression analysis identified postoperative uncorrected distance visual acuity and postoperative manifest refraction as significant predictors of night halo complaints after wavefront-guided LASIK (P < .01). CONCLUSIONS: In this large series of young patients with myopia treated with wavefront-guided LASIK, lowlight pupil diameter was not predictive of surgery satisfaction, ability to perform activities, or visual symptoms at 1 month postoperatively. Copyright © SLACK Incorporated. Source

Schallhorn S.C.,University of California at San Francisco | Venter J.A.,Optical Express | Hannan S.J.,Optical Express | Hettinger K.A.,Optical Express
Clinical Ophthalmology | Year: 2015

Purpose: The purpose of this study was to evaluate the refractive and visual outcomes of wavefront-guided laser in situ keratomileusis (LASIK) in eyes with myopic astigmatism and cylindrical component $2.0 diopter (D). Methods: In this retrospective study, 611 eyes that underwent LASIK for simple or compound myopic astigmatism were analyzed. Preoperative refractive cylinder ranged from -2.00 D to -6.00 D (mean -2.76±0.81 D), and the sphere was between 0.00 D and -9.75 D (mean -2.79±2.32 D). Predictability, visual outcomes, and vector analysis of changes in refractive astigmatism were evaluated. Results: At 3 months after LASIK, 83.8% of eyes had uncorrected distance visual acuity of 20/20 or better, 90.3% had manifest spherical equivalent within ±0.50 D, and 79.1% had residual refractive cylinder within ±0.50 D of intended correction. The mean correction ratio for refractive cylinder was 0.92±0.14, the mean error of angle was -0.45°±2.99°, and the mean error vector was 0.37±0.38 D. A statistically significant correlation was found between the error of magnitude (arithmetic difference in the magnitudes between surgically induced refractive correction and intended refractive correction) and the intended refractive correction (r=0.26, P,0.01). Conclusion: Wavefront-guided LASIK for the correction of myopic astigmatism is safe, effective, and predictable. © 2015 Schallhorn et al. Source

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