Photorefractive keratectomy for low-to-moderate myopia and astigmatism with a small-beam,tracker-directed excimer laser

ObjectiveTo assess the safety and effectiveness of the Autonomous Technologies Corporation LADARVision excimer laser system for photorefractive keratectomy correction of myopia and astigmatism.DesignA multicenter, prospective, noncomparative case series.ParticipantsThe cohort consisted of 467 eyes corrected for spherical myopia and 211 eyes corrected for myopia with astigmatism.InterventionTreatments 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 measuresVisual acuity, subjective refraction, corneal haze, intraocular pressure, complications, adverse reactions, patient satisfaction, and corneal endothelial changes.ResultsTwelve-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.ConclusionsPatients 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.     

Use of large optical zones with the LADARVision laser for myopia and myopic astigmatism

PURPOSE: To analyze the visual acuity, contrast sensitivity, and target deviations of patients who underwent laser in situ keratomileusis (LASIK) for spherical and astigmatic myopia with up to 8.0-mm laser optical zones. DESIGN: A retrospective noncomparative interventional case series. PARTICIPANTS: Three hundred fifty-two eyes of 186 patients in a refractive surgery practice. METHODS: Chart review of consecutive patients who underwent LASIK for spherical and astigmatic myopia with the Autonomous LADARVision excimer laser. MAIN OUTCOME MEASURES: The preoperative and the 3-month postoperative visual acuity and contrast sensitivity, as well as the target deviation, were assessed for each eye. The change in best spectacle-corrected visual acuity (BSCVA), best spectacle-corrected contrast sensitivity (BSCCS), and target deviation were analyzed by size of optical zone. RESULTS: For spherical myopes, uncorrected visual acuity (UCVA) was 20/20 or better in 55.7% of eyes. The mean deviation from target was -0.19 +/- 0.64 diopters (D), with 75.3% within +/-0.50 D of the target. None of the eyes lost more than two lines of BSCVA. A loss of three or more patches (levels) of BSCCS was seen in 2.7% of eyes, whereas a loss of four or more patches of BSCCS was seen in 1.1%. For astigmatic myopes, UCVA was 20/20 or better in 61.9% of eyes. The mean deviation from target was -0.17 +/- 0.55 D, with 67.5% within +/-0.50 D of the target. No eye lost more than two lines of BSCVA. A loss of three or more patches of BSCCS was seen in 4.3% of eyes, whereas a loss of four or more patches of BSCCS was seen in 1.2%. CONCLUSIONS: Larger optical diameters did not adversely affect BSCVA and BSCCS. Postoperative target deviation with the nomogram used was accurate with larger optical zones.     

Laser subepithelial keratomileusis for myopia of -6 to -10 diopters with astigmatism with the MEL60 laser

PURPOSE: To evaluate the efficacy, predictability, and safety of laser subepithelial keratomileusis (LASEK) for treatment of high myopia with astigmatism. METHODS: LASEK was performed in 61 eyes of 36 consecutive patients with myopic spherical equivalent refraction of -6.00 to -10.00 D using the Aesculap-Meditec MEL60 excimer laser. Data were collected prospectively with a follow-up of 6 to 17 months. Main outcome measures recorded were UCVA, BSCVA, residual refractive error, corneal haze, and complications. RESULTS: Ninety-six percent of eyes achieved 20/40 or better UCVA at 1 month. At 12 months, 64% of eyes achieved 20/20 and 92% achieved 20/40 or better UCVA. Two eyes lost 2 lines of BSCVA at 6 or 12 months. Accuracy of correction was +/- 0.50 D from emmetropia in 82% of eyes, and +/- 1.00 D in 90% at 12 months. No eye showed more than grade 1 haze. Grade 1 haze was observed in three eyes at 12 months. One patient had mild postoperative keratitis, which was successfully treated. CONCLUSIONS: LASEK with the Aesculap-Meditec MEL60 excimer laser appeared to be safe, effective, and highly predictable in treating high myopia.     

Laser in situ keratomileusis for myopia of -1.50 to -6.00 diopters

PURPOSE: To evaluate the results of laser in situ keratomileusis (LASIK) for the correction of low and moderate myopia and astigmatism using the Nidek EC-5000 excimer laser with a modified algorithm. METHODS: Three hundred and ninety-six eyes of 257 patients with myopia ranging from -1.50 to -6.00 D and astigmatism of no more than 4.00 D were included. Manifest spherical equivalent refraction, uncorrected and spectacle-corrected visual acuity were assessed at 1 month (357 eyes, 90%), 3 months (220 eyes, 56%), and 6 months (168 eyes, 42%) after LASIK. RESULTS: Mean preoperative spherical equivalent refraction was -3.60 +/- 1.27 D and mean cylinder was -1.01 +/- 1.08 D. Mean postoperative spherical equivalent refraction was -0.12 +/- 0.31 D and mean cylinder was -0.19 +/- 0.33 D. At 6 months follow-up, 158 eyes (94%) had a mean postoperative spherical equivalent refraction within +/- 0.50 D of emmetropia; 168 eyes (100%) were within +/- 1.00 D. Uncorrected visual acuity was 20/20 or better in 81% (136 eyes) and 20/40 or better in 100%. Two eyes (1.2%) lost 1 line of spectacle-corrected visual acuity due to a decentered ablation. No eye lost 2 or more lines of spectacle-corrected visual acuity. CONCLUSION: Our modified LASIK algorithm with the Nidek EC-5000 excimer laser resulted in safe and predictable outcomes for treatment of low and moderate amounts of myopia and astigmatism.     

Laser in situ keratomileusis for myopia and compound myopic astigmatism using the Technolas 217 scanning-spot laser

PURPOSE: To evaluate the safety, efficacy, predictability, and visual results of laser in situ keratomileusis (LASIK) using the Bausch & Lomb Technolas(R) 217 scanning-spot laser for the treatment of myopia and compound myopic astigmatism. SETTING: Stanford Eye Laser Center, Stanford, California, USA. METHODS: In a prospective study, 110 eyes of 58 patients with a mean spherical equivalent (SE) of -4.87 diopters (D) +/- 2.5 (SD) (range -1.0 to -11.4 D) had LASIK for myopia and compound myopic astigmatism using the Technolas 217 scanning-spot laser. The primary outcome variables included preoperative and postoperative best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity (UCVA), achieved versus attempted correction, vector analysis of astigmatism, and complications. RESULTS: One hundred ten eyes were available for analysis at 3 months. The mean SE refraction was reduced 95% (mean -0.23 +/- 0.4 D), and astigmatism was reduced 70% (mean 0.28 +/- 0.3 D). One day postoperatively, 100% of eyes had a UCVA of 20/40 or better, 96% had 20/25 or better, 77% had 20/20 or better, and 39% had 20/15 or better. At the 3-month examination, 100% of eyes had a UCVA of 20/40 or better, 95% had 20/25 or better, 83% had 20/20 or better, and 48% had 20/15 or better. Ninety percent of eyes were within +/-0.5 D of emmetropia. No eye lost 2 or more lines of BSCVA. CONCLUSIONS: The Technolas 217 scanning-spot laser produced excellent postoperative UCVA and BSCVA. It was predictable, safe, and effective for the treatment of myopia and compound myopic astigmatism. Long-term follow-up is needed to assess the stability of the procedure.     

Analysis of the efficacy, predictability, and safety of LASEK for myopia and myopic astigmatism using the Technolas 217 excimer laser

PURPOSE: To evaluate the efficacy, predictability, and safety of laser-assisted subepithelial keratectomy (LASEK) for the treatment of myopia and myopic astigmatism. SETTING: Stanford University Eye Laser Center, Stanford, California, USA. METHODS: This retrospective analysis comprised 102 eyes that had LASEK for myopia using the Bausch & Lomb Technolas 217 excimer laser. Primary outcome variables including uncorrected visual acuity (UCVA), best spectacle- corrected visual acuity (BSCVA), manifest refraction, and complications were evaluated at 3, 6, and 12 months. Vector analysis was performed on eyes that received astigmatic correction. RESULTS: The mean spherical equivalent was -7.03 diopters (D) +/- 2.61 (SD) preoperatively, +0.19 +/- 0.64 D at 3 months, +0.23 +/- 0.82 D at 6 months, and +0.03 +/- 0.63 D at 12 months (P<.001). At 3, 6, and 12 months, the UCVA was 20/20 or better in 66%, 67%, and 83% of eyes, respectively, and 20/40 or better in 98%, 99%, and 100%; 74%, 70%, and 83%, respectively, were within +/-0.5 D of emmetropia, and 89%, 86%, and 97%, respectively, were within +/-1.0 D. No eye lost more than 2 lines of BSCVA. At 3, 6, and 12 months, 10.0%, 8.7%, and 0% of eyes, respectively, had trace corneal haze. Vector analysis found a success rate of approximately 78% to 80% in achieving the astigmatic surgical correction at the 3 postoperative visits. CONCLUSIONS: Laser-assisted subepithelial keratectomy was an effective, predictable, and safe procedure for the treatment of myopia and myopic astigmatism. Further studies are needed to determine the role of LASEK in the refractive surgery spectrum.     

LASIK correction of spherical hyperopia,hyperopic astigmatism,and mixed astigmatism with the LADARVision excimer laser system

OBJECTIVE: To assess the safety and effectiveness of the LADARVision active tracking narrow beam excimer laser system (Alcon Surgical, Orlando, FL) using laser in situ keratomileusis (LASIK) for correction of spherical hyperopia, hyperopic astigmatism, and mixed astigmatism. DESIGN: A multicenter, prospective non-randomized (self-controlled) comparative trial. PARTICIPANTS: A total of 360 eyes, including 152 spherical hyperopic, 143 hyperopic astigmatic, and 65 mixed astigmatic, were treated for up to +6.00-diopter (D) sphere with up to -6.00-D cylinder. INTERVENTION: Treatments were performed at six sites in the United States using a 6-mm optic zone with a 1.5-mm peripheral blend zone for a maximum ablation zone diameter of 9 mm. MAIN OUTCOME MEASURES: Uncorrected visual acuity (UCVA), manifest refraction, vector analysis, best spectacle-corrected visual acuity (BSCVA), complications and adverse reactions, subjective symptoms, and patient satisfaction. RESULTS: Six and 12 months of follow-up, respectively, were available on 143 and 117 spherical hyperopic eyes, 124 and 74 hyperopic astigmatic eyes, and 57 and 38 mixed astigmatic eyes, respectively. For spherical hyperopes at 6 and 12 months, UCVA was 20/40 or better in 93.4% and 93.9% of eyes, respectively. The manifest refraction spherical equivalent (MRSE) was within 0.50 D of intended in 65.0% and 74.1% of eyes, respectively, and within 1.00 D in 87.4% and 91.4%, respectively. Refractive stability was demonstrated in 94.2% or more of eyes between the intervals of 1 to 3 months and 3 to 6 months and in 95.3% or more of eyes to 12 months. A loss of two lines of BSCVA occurred in 3.5% and 3.4%, respectively, and no eyes lost more than two lines. For hyperopic astigmats at 6 and 12 months, UCVA was 20/40 or better in 90.9% and 93.8% of eyes, respectively. The MRSE was within 0.50 D of intended in 60.5% and 73.0% of eyes, respectively, and within 1.00 D in 88.7% and 89.2% of eyes, respectively. Refractive stability was demonstrated in 96.5% or more of eyes, respectively, between the intervals of 1 to 3 months and 3 to 6 months and 95.5% or more to 12 months. A loss of two lines of BSCVA occurred in 5.8% and 1.4% of eyes, respectively, and no eyes lost more than two lines. For mixed astigmats at 6 and 12 months, UCVA was 20/40 or better in 92.6% and 94.4% of eyes, respectively. The MRSE was within 0.50 D of intended in 64.9% and 73.7% of eyes, respectively, and within 1.00 D in 87.7% and 94.7% of eyes, respectively. Refractive stability was demonstrated in 100% of eyes between the intervals of 1 to 3 months and 3 to 6 months and in 97.0% or more to 12 months. A loss of two lines of BSCVA occurred in 1.9% and 0.0% of eyes, respectively, and no eyes lost more than two lines. CONCLUSIONS: The data support safety and effectiveness of the LASIK correction of spherical hyperopia, hyperopic astigmatism, and mixed astigmatism with the LADARVision system.     

Nomogram adjustment of laser in situ keratomileusis for myopia and myopic astigmatism with the Alcon LADARVision system

PURPOSE: To evaluate the visual and refractive results of conventional (non-wavefront) laser in situ keratomileusis (LASIK) for treatment of myopia and myopic astigmatism using the Alcon LADARVision 4000 excimer laser system and nomogram adjustment techniques. METHODS: A retrospective analysis of 499 eyes that had LASIK for myopia and myopic astigmatism was performed. Preoperative manifest spherical equivalent refraction ranged from -0.43 to -6.00 D and preoperative astigmatism ranged from 0 to -4.75 D. Patients were evaluated during 3 months following surgery. RESULTS: One month after surgery, 72% of eyes examined (298/415 eyes) had uncorrected visual acuity (UCVA) of 20/20 or better. Three months after surgery, 83% of eyes examined (216/261 eyes) had UCVA of 20/20 or better. One and three months after surgery, 82% and 83% of eyes, respectively, were within +/-0.50 D of attempted correction; 97% of eyes were within +/-1.00 D at both 1 and 3 months. No eye lost more than 1 line of best spectacle-corrected visual acuity (BSCVA) at 3 months after surgery. At the 3-month examination, 83% of eyes had UCVA better than or equal to preoperative BSCVA. CONCLUSIONS: Conventional LASIK to correct myopia and myopic astigmatism was safe and effective using the Alcon LADARVision 4000 excimer laser system. Outcomes were substantially improved throughout development of an accurate nomogram, derived from continually updated regression analysis of previous refractive results.     

Results of laser in situ keratomileusis for myopia of -10 to -19 diopters with a Technolas 217 laser

PURPOSE: To evaluate the effectiveness, predictability, and safety of laser in situ keratomileusis (LASIK) for correcting myopia greater than -10.00 D. METHODS: Sixty-five eyes of 37 patients with myopia greater than -10.00 D underwent LASIK. Patients were evaluated on day 1, 1 week, 1, 3, and 6 months after surgery. Parameters evaluated were uncorrected visual acuity (UCVA) and best spectacle-corrected visual acuity (BSCVA), residual refractive error, regression of correction, and presence of any complication. RESULTS: Mean preoperative BSCVA was 0.745 +/- 0.234, which improved to 0.8070 +/- 0.237 postoperatively. The average preoperative UCVA was 0.022 +/- 0.02; postoperative UCVA at 6 months was 0.536 +/- 0.255. UCVA of 20/40 or better was achieved in 58% (38 eyes) and 20/20 or better in 26% (17 eyes). The average refractive error before LASIK was -12.64 +/- 2.16 D (range -10.00 to -19.00 D). Mean residual refractive error 1 week following LASIK was -0.63 +/- 1.36 D, which regressed to a mean -1.78 +/- 2.08 D at the end of 6 months. Nineteen eyes (29%) were within +/-0.50 D of intended refractive correction. CONCLUSION: LASIK was partially effective in the correction of high myopia. An initial overcorrection may be programmed to offset the effect of refractive regression.     

CustomVue laser in situ keratomileusis for myopia and myopic astigmatism using the Visx S4 excimer laser: Efficacy, predictability, and safety

PURPOSE: To evaluate the efficacy, predictability, and safety of custom laser in situ keratomileusis (LASIK) using the Visx wavefront platform CustomVue for the treatment of myopia and myopic astigmatism. SETTING: Stanford University Eye Laser Center, Stanford, California, USA. METHODS: This retrospective analysis was of the initial 140 eyes of 78 patients treated consecutively with LASIK for myopia using the Visx Star S4 excimer laser. Primary outcome variables, including uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), manifest refraction, and complications, were evaluated at 1 week and 1 and 3 months. Vector analysis was performed on eyes that received astigmatic correction. RESULTS: Mean preoperative spherical equivalent (SE) was reduced from -3.89 diopters +/- 1.48 (SD) to an SE of -0.21 +/- 0.36 D at 1 month and -0.28 +/- 0.36 D at 3 months (P < .001). At 1 and 3 months, UCVA was 20/20 or better in 84.3% and 87.9%, respectively. Eighty-six percent of eyes at 1 month and 81.4% of eyes at 3 months were within +/-0.5 D of emmetropia. No eyes lost more than 2 lines of BSCVA. Vector analysis yielded an index of success of 0.39, indicating a 61% success rate in achieving the astigmatic surgical correction at 3 months. The preoperative root-mean-square value of 0.28 +/- 0.08 microm increased slightly to 0.33 +/- 0.11 microm at 1 month and 0.34 +/- 0.11 microm at 3 months. CONCLUSION: Wavefront-guided LASIK using the Visx CustomVue system was effective, predictable, and safe for correction of low to moderate myopic refractive error.     

Wavefront-guided photorefractive keratectomy for myopia and myopic astigmatism

PURPOSE: To evaluate the results of wavefront-supported customized ablation (WASCA) in eyes treated with photorefractive keratectomy (PRK) to correct spherical myopia and myopic astigmatism. METHODS: One-hundred fifty eyes of 104 patients (mean age 33.4 +/- 4.4 years) were included in the study. An Asclepion Shack-Hartmann wavefront aberrometer was used to assess lower and higher order refractive aberrations of eyes, and customized PRK treatments were carried out using the Asclepion-Meditec MEL 70 G-Scan excimer laser. Follow-up time was 6 months. RESULTS: The mean preoperative spherical equivalent refraction was -4.02 +/- -1.04 D, and mean uncorrected visual acuity (UCVA) was 0.06 +/- 0.02. Postoperatively, mean UCVA was 1.04 (better than 20/20), mean best spectacle-corrected visual acuity was 1.22 (20/16), and average spherical equivalent refraction was -0.12 D; 98.6% (148 of 150 eyes) were within +/-0.50 D of intended refraction, and 100% were within +/-1.00 D. Concerning safety, in 71.1% of eyes (107 of 150) BSCVA was the same as preoperatively, and in 8.2% (11 of 150) it increased by two or more Snellen lines. None of the eyes lost two or more lines of BSCVA. The root mean square value for higher order aberrations increased 1.4 times following PRK. CONCLUSIONS: WASCA-guided PRK was efficacious, safe and predictable; BSCVA may be improved by the WASCA method compared to results achievable with a traditional PRK technique, in spite of an increase in the root mean square value for higher-order aberrations.     

Ten-year follow-up of laser in situ keratomileusis for myopia of up to -10 diopters

PURPOSE: To evaluate the long-term outcomes of laser in situ keratomileusis (LASIK) for myopia of up to -10 diopters (D). DESIGN: A long-term (10-year) follow-up retrospective, interventional case series. METHODS: The study included 97 eyes of 70 patients with a preoperative spherical equivalent (SE) of up to -10 D treated with myopic LASIK at the Instituto Oftalmológico de Alicante, Alicante, Spain, using the VISX 20/20 excimer laser (Santa Clara, California, USA) and the Automated Corneal Shaper microkeratome (Chiron Vision, Irvine, California, USA). All patients were evaluated three months, one year, two years, five years, and 10 years after surgery. The main outcome measures were refractive predictability and stability, mean corneal keratometry, topographical cylinder, safety, efficacy, stability of visual acuity, and postoperative complications. RESULTS: At 10 years, 71 (73%) of 97 eyes were within +/- 1.00 D and 89 (92%) were within +/- 2.00 D. Twenty eyes (20.8%) underwent retreatments because of overcorrection, undercorrection, regression, or both. The mean SE slightly decreased (myopic regression) over 10 years, with a mean myopic regression of -0.12 +/- 0.16 D per year. Fifty-four (54.6%) of 97 eyes demonstrated an increase in best spectacle-corrected visual acuity (BSCVA) after 10 years. No eye developed corneal ectasia in the long-term, and only three eyes lost more than two lines of BSCVA because of complications that were not attributable to the LASIK procedure. CONCLUSIONS: LASIK for myopia of up to -10 D is a safe and effective procedure with slight myopic regression that slows down with time and a high rate of BSCVA increase in the long-term.     

Laser in situ keratomileusis for myopic astigmatism with the Nidek EC-5000 laser

PURPOSE: We studied the efficacy, predictability, and safety of laser in situ keratomileusis (LASIK) for moderate to high simple and compound myopic astigmatism. METHODS: Ninety-two eyes of 46 consecutive patients who had LASIK for myopic astigmatism (64 eyes, astigmatism 3.00 to 9.00 D; myopia 0 to -20.00 D), or simple myopia (28 eyes, myopia -4.00 to -20.00 D; astigmatism 0 to 0.50 D) were retrospectively studied. Mean baseline spherical equivalent refraction (SE) in the myopia group was -8.11 +/- 3.94 D and in the astigmatism group, -8.55 +/- 4.49 D. All eyes underwent LASIK using the Nidek EC-5000 laser by the same surgeon. RESULTS: At 6 months after LASIK in the myopia group versus the astigmatism group, 24 eyes (85%) vs. 54 eyes (84%) were available for follow-up, 12 eyes (50%) vs. 13 eyes (24%) had uncorrected visual acuity (UCVA) of 20/20, 19 eyes (79%) vs. 44 eyes (81%) had UCVA of 20/40, 8 eyes (33%) vs. 18 eyes (33%) had SE within +/- 0.50 D, 15 eyes (62%) vs. 39 eyes (72%) had SE within +/- 1.00 D, and mean SE was -1.22 +/- 1.17 D vs. -0.74 +/- 1.46 D. Mean astigmatism (vertexed to the corneal plane) in the astigmatism group was 2.77 D at 0 degrees before surgery and 0.32 D at 7 degrees at 6 months. None of the myopic eyes and three of the astigmatic eyes (5%) lost > or = 2 lines of best spectacle-corrected visual acuity. CONCLUSION: LASIK with the Nidek EC-5000 laser for myopic astigmatism was reasonably effective, predictable, and safe. Astigmatism was under-corrected with the nomogram implemented in this study.     

Arcuate relaxing incisions with a 5.00-mm optical zone for the correction of high postcataract astigmatism

The purpose of this study was to investigate the efficacy and safety of arcuate cuts with a 5-mm optical zone to correct high postoperative astigmatism after extracapsular cataract extraction. We performed 5-mm optical zone arcuate cuts on 23 eyes of 23 patients with high postoperative astigmatism. Ophthalmic examination included uncorrected visual acuity (UCVA), best spectacle corrected visual acuity (BSCVA) and the amount of the refractive and keratometric cylinder before and 9 months after operation. Surgically induced refractive change was calculated in all cases. A significant reduction in astigmatism was achieved in all cases with minimal axis deviation. No case developed clinically significant irregular astigmatism. The mean magnitude of astigmatism of the surgically induced refractive change calculated from standard keratometry and refractive data was 3.73+/-0.72 and 3.70+/-0.77 dptr, respectively. The mean axis deviation calculated from the keratometric and refractive data was 1.18+/-2.33 and 1.32+/-3.62 degrees, respectively. At the last examination, 78.2% of the eyes had UCVA of 20/40 or better. No eye lost more than two lines of vision, 6 eyes lost one line, 2 eyes gained one and 1 eye gained two lines of BSCVA. The above data show that the 5-mm optical zone arcuate astigmatic keratotomy is an effective and safe method of correcting high postoperative astigmatism.     

Comparison between LASEK with mitomycin C and LASIK for the correction of myopia of -7.00 to -13.75 D

PURPOSE: To compare laser epithelial keratomileusis (LASEK) and LASIK for the correction of high myopia. METHODS: A prospective, single-masked study was conducted. Patients treated with LASEK to correct myopia > or = -7.00 diopters (D) (spherical equivalent manifest refraction) with a cylinder < or = -3.50 D (LASEK group) were compared to patients treated with LASIK (LASIK group) using the same excimer laser (Technolas 217C). Mitomycin C (MMC) 0.02% was applied for 1 minute in all LASEK-treated eyes. RESULTS: A total of 228 consecutive eyes were included in the study (114 in each group, matched for preoperative refraction). The mean preoperative spherical equivalent manifest refraction was -8.72 +/- 1.20 D in the LASEK group and -8.74 +/- 1.20 D in the LASIK group (range: -7.00 to -13.75 D) (P = .9). Uncorrected visual acuity (UCVA) was significantly lower in LASEK eyes 1, 7, and 30 days postoperatively (P = .0001 for each comparison). No significant differences were found at 3 months postoperatively in UCVA (P = .3), best spectacle-corrected visual acuity (BSCVA) (P = .2), or in the safety (P = .6) and efficacy (P = .8) indices. Uncorrected visual acuity was 1.0 or better in 34.2% of LASEK eyes and 44.7% of LASIK eyes. Spherical refraction was +0.25 +/- 0.6 D after LASEK and -0.06 +/- 0.5 D after LASIK (P = .0001). Sixty-eight percent of LASEK eyes and 79% of LASIK eyes were within +/- 0.50 D of intended refraction. No LASEK eye versus 7 LASIK eyes lost 2 lines of BSCVA. Eight LASEK eyes gained 2 or more lines of BSCVA versus 1 LASIK eye. CONCLUSIONS: Visual improvement after LASEK with intraoperative MMC was significantly slower than after LASIK. Visual outcomes (UCVA, BSCVA, and safety and efficacy indices) 3 months after surgery were similar with both techniques for the correction of high myopia. Ten percent more eyes after LASIK were within +/- 0.50 D of intended refraction.     

Laser in situ keratomileusis with the VISX Star laser for myopia over -10.0 diopters.

PURPOSE: To evaluate the efficacy, predictability, stability, and safety of laser in situ keratomileusis (LASIK) for myopia over -10.00 diopters (D). SETTING: The Eye Institute of Utah, Salt Lake City, Utah, USA. METHODS: The prospective study included 332 eyes of 183 patients having LASIK with the VISX Star laser to correct myopia of -10.00 to -18.00 D. The eyes were divided into 3 groups according to the preoperative refraction: Group A (n = 208), -10.00 to -11.90 D; Group B (n = 94), -12.00 to -14.00 D; Group C (n = 30), -14.10 to -18.00 D. The mean follow-up was 12.0 months +/- 5.6 (SD) (range 6 to 37 months). RESULTS: Overall, the mean spherical equivalent decreased 96%, from -11.69 +/- 1.46 D preoperatively to -0.37 +/- 0.80 D postoperatively. The mean astigmatism decreased 72%, from 1.66 +/- 1.22 D to 0.46 +/- 0.53 D. At the last visit, 84.0% of eyes were within +/-1.00 D of emmetropia and 96.4% were within +/-2.00 D. An overcorrection of more than +1.00 D was experienced by 1.8% of patients. The uncorrected visual acuity (UCVA) was 20/20 or better in 45.8% of eyes and 20/40 or better in 89.5%. Six eyes (1.8%) lost 2 or more lines of best corrected visual acuity; this included 1 eye in which iatrogenic keratectasia developed 18 months after LASIK retreatment. Retreatment was done in 37.0% of eyes at a mean of 6.3 +/- 5.3 months (3 to 32 months) after the initial treatment. At the last examination, 86.0% of eyes in Groups A and B and 70.0% in Group C were within +/-1.00 D of emmetropia. A significant difference was found between Groups A and C (P =.032). The UCVA was 20/20 in 52.0% of Group A eyes, 38.0% of Group B eyes, and 23.0% of Group C eyes. The difference between Groups A and C was significant (P =.001), but the difference between Groups A and B was not (P =.055). CONCLUSIONS: In this study, LASIK was effective in correcting myopia up to -14.00 D. The efficacy, predictability, and safety were significantly less in eyes with myopia greater than -14.00 D.     

Laser in situ keratomileusis for compound myopic astigmatism using the Meditec MEL 70 G-Scan excimer laser

PURPOSE: To determine the safety, efficacy, predictability, and stability of laser in situ keratomileusis (LASIK) in treating patients with myopic astigmatism using the Meditec MEL 70 G-Scan excimer laser. METHODS: Seventy-four eyes of 42 patients with myopia ranging from -4.50 to -9.88 D and astigmatism ranging from 0.50 to 4.00 D who underwent LASIK with the Meditec MEL 70 G-Scan excimer laser and the Summit Krumeich-Barraquer microkeratome were studied. Patients were followed for 1 year. RESULTS: Mean baseline spherical equivalent refraction was -7.12 +/- 1.70 D and cylinder was 1.62 +/- 1.72 D. At 12 months, mean postoperative spherical equivalent refraction was -0.49 +/- 0.57 D and mean refractive cylinder was 0.59 +/- 0.32 D. Mean change in spherical equivalent refraction between 1 and 12 months after surgery was -0.09 +/- 0.31 D, toward myopia. At baseline, no eyes had best spectacle-corrected visual acuity (BSCVA) of 20/20 or better, and 65% had 20/40 or better. At 12 months after surgery, 10% of eyes had BSCVA of 20/20 or better and 88% of eyes had 20/40 or better. The unusually low postoperative BSCVA results were thought to be due to amblyopia or existence of a higher percentage of some optical aberrations in this group of eyes. Mean uncorrected visual acuity was -1.38 +/- 0.42 LogMAR units (20/400) at baseline and -0.29 +/- 0.25 LogMAR units (20/40) at the 12-month postoperative examination. No eyes lost two or more lines of spectacle-corrected visual acuity. No vision threatening complications were observed. CONCLUSIONS: LASIK with the Meditec MEL 70 G-Scan excimer laser appeared to be safe, effective, reasonably predictable, and stable for correction of myopic astigmatism with a spherical component between -4.25 and -8.25 D and a cylindrical component between 0.50 and 4.00 D. However, astigmatism was slightly undercorrected with the algorithm used.     

Laser-assisted subepithelial keratectomy for low to high myopia and astigmatism

PURPOSE: To evaluate the safety and efficacy of laser-assisted subepithelial keratectomy (LASEK) for the treatment of low to high myopia and astigmatism. SETTING: Solo private practice, Mountain View, California, USA. METHODS: Laser-assisted subepithelial keratectomy was performed in 146 eyes of 83 consecutive patients with myopia or myopic astigmatism using a VISX Star S2 excimer laser (72 eyes) or a Nidek EC-5000 excimer laser (74 eyes). The mean preoperative myopic spherical equivalent was -5.32 diopters (D) (range -1.25 to -14.38 D). Data were collected prospectively with a follow-up of 1 to 12 months. Outcome measurements included uncorrected visual acuity (UCVA), manifest refraction, best spectacle-corrected visual acuity (BSCVA), corneal haze, and complications. RESULTS: After 6 and 12 months, no eye lost 2 or more lines of BSCVA. After 6 months, the UCVA was 20/20 in 57% of eyes and 20/40 or better in 96%. After 12 months, it was 20/20 in 56% of eyes and 20/40 or better in 96%. No eye developed corneal haze that affected visual acuity. There were no serious or vision-threatening complications. CONCLUSIONS: Laser-assisted subepithelial keratectomy was safe and effective in treating a wide range of myopia and astigmatism. The potential advantages of LASEK over laser in situ keratomileusis (LASIK) include the elimination of stromal flap complications and greater choice in patient selection. The disadvantages include varying degrees of pain for 2 days and blurry vision for several days postoperatively.     

LASIK for myopia with the Zeiss meditec MEL 80

PURPOSE: To prospectively evaluate a new high-speed, small spot-scanner laser for the correction of myopia and myopic astigmatism. METHODS: Seventy-six consecutive eyes with myopia and myopic astigmatism between -1.00 and -8.25 diopters (D) and up to -2.75 D astigmatism underwent LASIK treatment using the MEL 80 laser (Carl Zeiss Meditec, Jena, Germany). Parameters evaluated were uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), residual refractive error, regression of correction, and aberrometry. RESULTS: Mean preoperative BSCVA was 20/20, which improved to 20/18 postoperatively. Postoperative UCVA was 20/20 at 1 month and 20/18 at 1 year. Uncorrected visual acuity > or = 20/20 was achieved in 58 (83%) of 70 eyes at 1 month and in 60 (88%) of 68 eyes at 1 year. The average refractive error before LASIK was -4.41 +/- 1.98 D. The mean residual refractive error was 0.14 +/- 0.31 D at 1 month and 0.13 +/- 0.30 D at 1 year. At 1-month and 1-year follow-up, respectively, 66 (94%) of 70 eyes and 65 (96%) of 68 eyes were within +/- 0.50 D of intended refractive correction. No eye lost two lines. At 1 month 17% of eyes and at 1 year 13% of eyes gained two lines or more. Between 1-month and 1-year follow-up, 100% of eyes were stable. Mean root-mean-square high order aberration changed from 0.20 microm preoperatively to 0.28 microm postoperatively. CONCLUSIONS: The MEL 80 is effective and safe in the treatment of myopia and myopic astigmatism.     

Tracker-assisted laser in situ keratomileusis for myopia using the autonomous scanning and tracking laser: 12-month results

OBJECTIVE: To determine the safety, efficacy, and predictability of the Autonomous scanning and tracking laser for the correction of myopia and myopic astigmatism with laser in situ keratomileusis (LASIK) procedure. DESIGN: Retrospective, noncomparative case series. PARTICIPANTS: The first 129 consecutive eyes with up to -13.00 diopters (D) of myopia and -5.00 D of astigmatism. INTERVENTION: Myopic tracker-assisted LASIK (T-LASIK) using the Autonomous Laser (Alcon Summit Autonomous, Waltham, MA) and Hansatome microkeratome (Bausch & Lomb Surgical, Bracknell, England). MAIN OUTCOME MEASURES: Uncorrected visual acuity (UCVA), manifest spherical equivalent (MSE), best spectacle-corrected visual acuity (BSCVA), and complications were studied. RESULTS: At 12 months, the mean MSE was -0.02 +/- 1.01 D, with 79.1% of eyes within 0.5 D and 89.9% of eyes within 1 D of the intended correction. UCVA was 20/20 or better in 71.4%, 20/25 or better in 78.5%, and 20/40 or better in 92.8% of eyes. Two eyes (1.6%) lost 2 lines and five eyes (3.8%) gained 2 lines of BSCVA. Sixteen eyes (12.4%) required retreatment to correct residual myopia or astigmatism. After retreatment, 14 of 16 eyes were within 0.5 D of emmetropia. Nine eyes (6.9%) had minor flap complications; two eyes (1.6%) had grade 2 diffuse lamellar keratitis, of which one eye had associated peripheral flap melt. One eye showed slight decentration; this eye was rolling throughout the procedure. All eyes had some dryness, with 10% severe enough to require temporary punctual occlusion with plugs. CONCLUSIONS: T-LASIK for myopic astigmatism with the Autonomous Laser is relatively safe, effective, and predictable. The tracker seems to be effective, and the complications are relatively few. Retreatment rates are acceptable and can be performed safely and effectively to improve visual outcome. The outcomes are comparable with other published data.