Faculty Bibliography

OBJECTIVE: To assess the safety and effectiveness of the Summit Autonomous LADARVision active tracking narrow beam excimer laser system for laser in situ keratomileusis (LASIK) correction of myopia and astigmatism. DESIGN: A multicenter, prospective noncomparative case series. PARTICIPANTS: This cohort consisted of 177 eyes corrected for spherical myopia up to -11 diopters (D) and 170 eyes corrected for myopia up to -11 D spherical equivalent with astigmatism up to -5 D. INTERVENTION: Treatments were performed at four sites in the United States using a 6-mm optic zone for spherical myopes and a 5.5-mm optic zone with a 1-mm blend for astigmats. MAIN OUTCOME MEASURES: Visual acuity, subjective refraction, vector analysis, subject satisfaction, intraocular pressure, complications, and adverse reactions. RESULTS: Six-month follow-up was available on 157 spherical eyes and 113 astigmatic eyes. For spherical myopes, uncorrected visual acuity (UCVA) was 20/20 or better in 60.5%, 20/25 or better in 80.3%, and 20/40 or better in 93.9%. The mean spherical equivalent was -0.29 +/- 0.45 D with 75.2% +/- 0.50 D and 94.9% +/- 1.00 D of intended. A loss of two lines of best spectacle-corrected visual acuity (BSCVA) occurred in 0.6%, and no eyes lost greater than two lines of BSCVA. For astigmatic myopes, UCVA was 20/20 or better in 52.0%, 20/25 or better in 74.5%, and 20/40 or better in 94.1%. The mean spherical equivalent was -0.23 +/- 0.49 D with 75.2% +/- 0.50 D and 95.6% +/- 1.00 D of intended. A loss of two lines of BSCVA occurred in 0.9%, and no eyes lost greater than two lines of BSCVA. Vector analysis showed that 99% of the intended cylinder was corrected on average with a mean angle of error of 4.2 degrees. Refractive stability was achieved between 1 and 3 months in 97.5% of spherical eyes and 99.4% of astigmatic eyes and confirmed between 3 and 6 months in 100% of both spherical and astigmatic eyes. CONCLUSIONS: Eyes treated for myopia up to -11 D of spherical equivalent with or without astigmatism up to -5 D show early refractive stability, good UCVA outcomes, no significant loss of BSCVA, accurate correction of astigmatism, and slight undercorrection without a change from the photorefractive keratectomy algorithm and with a single treatment

BACKGROUND/PURPOSE: Conductive keratoplasty (CK) is a surgical technique that delivers radio frequency (350 kHz) current directly into the corneal stroma through a Keratoplasty tip inserted into the peripheral cornea at 8 to 32 treatment points. A full circle of CK spots produces a cinching effect that increases the curvature of the central cornea, thereby decreasing hyperopia. We report here the 12-month results of a 2-year, prospective, multicenter US clinical trial conducted to evaluate the efficacy, safety, and stability of CK. METHODS: A total of 233 patients (401 eyes) with preoperative hyperopia of +0.75 to +3.00 D and < or = 0.75 D of astigmatism (mean preoperative manifest refractive spherical equivalent = +1.76 D +/- 0.60) were enrolled into the study at 13 centers and underwent CK treatment. RESULTS: Twelve-month postoperative data are available on 203 eyes for safety and stability and 171 eyes for safety, stability, and efficacy. A total of 91% had uncorrected visual acuity (UCVA) of 20/40 or better, and 51% had UCVA of 20/20 or better. Manifest refractive spherical equivalent was within +/- 0.50 D in 58%, within +/- 1.00 D in 91%, and within +/- 2.00 D in 99%. The mean change in residual refraction was 0.26 D +/- 0.49 between 3 and 6 months, 0.09 D +/- 0.37 between 6 and 9 months, and 0.13 D +/- 0.39 between 9 and 12 months. CONCLUSIONS: One-year data show safety and efficacy of CK in the treatment of hyperopia. Changes in residual refractive error after CK appeared to be small, suggesting that a stable refraction could be achieved by 6 months

OBJECTIVE: To determine the effects of laser in situ keratomileusis (LASIK) on best-corrected visual acuity (BCVA) and contrast sensitivity. DESIGN: Prospective, observational case series. PARTICIPANTS: One hundred twelve eyes, in 65 patients with myopia and myopia with astigmatism, who underwent LASIK. TESTING AND MAIN OUTCOME MEASURES: Best-corrected visual acuity using the Snellen visual acuity chart and contrast sensitivity using the CSV 1000 (Vector Vision, Dayton OH) was tested before surgery and 1 week, 1 month, and 3 months after surgery in patients who underwent LASIK. RESULTS: Contrast sensitivity was depressed for patient eyes with spherical equivalence (SE) between -1.25 diopters (D) and -13.75 D, at 12 cycles/degree for at least 3 months and at 18 cycles/degree for 1 week after LASIK. For patient eyes with SE between -1.25 D and -6.00 D, contrast sensitivity was depressed only at 12 cycles/degree for at least 3 months after LASIK. For patient eyes with SE between -6.00 D and -13.75 D, contrast sensitivity was depressed at 6, 12, and 18 cycles/degree 1 week after LASIK but returned toward preoperative levels by 1 month after surgery. Despite the slight decreases in contrast sensitivity, all scores were still within the range of normal values except for 12 cycles/degree for 3 months and 18 cycles/degree at 1 week after surgery in the high myopia group. Although highly myopic patients, compared with patients with low myopia, had slightly less BCVA before surgery, both groups maintained their preoperative BCVA at all postoperative visits. CONCLUSIONS: Based on this study, we conclude that LASIK has little effect on BCVA and contrast sensitivity for up to 3 months after surgery

OBJECTIVE: To assess the safety and effectiveness of the Autonomous Technologies Corporation LADARVision excimer laser system for photorefractive keratectomy correction of myopia and astigmatism. DESIGN: A multicenter, prospective, noncomparative case series. PARTICIPANTS: The cohort consisted of 467 eyes corrected for spherical myopia and 211 eyes corrected for myopia with astigmatism. INTERVENTION: Treatments were performed at six sites in the United States using a 6-mm ablation zone for spherical myopes and a 5.5-mm zone with a 1.0-mm blend for astigmats. MAIN OUTCOME MEASURES: Visual acuity, subjective refraction, corneal haze, intraocular pressure, complications, adverse reactions, patient satisfaction, and corneal endothelial changes. RESULTS: Twelve-month follow-up was available on 414 spherical eyes and 175 astigmatic eyes. The results for spherical eyes with correction between -1 and -5.99 diopters (D) were: uncorrected visual acuity (UCVA) of 20/40 or better achieved by 98.1%, 20/20 or better by 72%, 1.8% lost 2 lines and 0.3% lost greater than 2 lines of best spectacle-corrected visual acuity (BSCVA); 76.4% were within 0.50 D of the target correction and 94.4% were within 1.00 D. The results for myopia with astigmatism with spherical equivalent correction between -1 and -5.99 D were: UCVA of 20/40 or better in 97.4%, 20/20 or better in 61.7%, 2.5% lost 2 lines and no eyes lost greater than 2 lines BSCVA; 73.9% were within 0.50 D of the target correction and 95% were within 1.00 D. For spherical myopes combined with myopic astigmats corrected for 6 to 10 D, results were: UCVA of 20/40 or better in 93.4%, 20/20 or better in 61.2%, 2.3% lost 2 lines and no eyes lost greater than 2 lines of BSCVA; 67.2% were within 0.50 D of the desired correction and 87.8% were within 1.00 D. Refractive stability was achieved between 3 and 6 months for the spherical and astigmatic groups. No eyes had corneal haze graded as moderate or greater, and there was no significant decrease in endothelial cell density. CONCLUSIONS: Patients treated for 1 to 10 D of spherical equivalent myopia, with or without astigmatism, showed early refractive stability, excellent UCVA, no significant loss of BSCVA, no loss of endothelial cell density, and very low levels of corneal haze to 12 months after surgery