Flap lift for LASIK retreatment in eyes with myopia

PURPOSE: To analyze the results achieved with LASIK retreatment after lifting the original flap in a large series of patients. DESIGN: Retrospective, noncomparative, interventional consecutive case series. PARTICIPANTS: Two thousand four hundred twenty-two consecutive eyes undergoing LASIK surgery for myopia, including 334 eyes submitted to flap lift for LASIK retreatment. MAIN OUTCOME MEASURES: Uncorrected visual acuity, best-corrected visual acuity, refractive error, and complications. RESULTS: LASIK retreatment was performed in 334 eyes (14%), and the mean time between initial procedure and retreatment was 8.2+/-6.2 months. The mean spherical equivalent (SE) improved from -1.2+/-0.6 diopters (D) (range, -4.2 to +1.2 D) before retreatment to +0.2+/-0.4 D (range, -3.1 to +1.1 D) after the retreatment. The uncorrected visual acuity (UCVA) after retreatment was 20/20 or better in 58% and 20/40 or better in 92% of eyes. The mean SE was within +/-1.0 D in 96% of the patients and within +/-0.5 D in 80.5% after retreatment. Eighteen eyes (5%) lost 1 line of best-corrected visual acuity, and 4 eyes (1%) lost 2 lines. CONCLUSIONS: LASIK retreatment surgery performed by relifting the flap was a useful procedure for correcting residual refractive errors after the primary LASIK procedure. It provided good uncorrected visual acuity, predictable results, good refractive stability, and few complications.     

Results of resident-performed laser in situ keratomileusis

PURPOSE: To analyze the results of resident-performed laser in situ keratomileusis (LASIK). SETTING: Rush University Medical Center, Department of Ophthalmology, Chicago, Illinois, USA. METHODS: This retrospective study comprised 44 consecutive eyes of 22 patients who had LASIK performed from August 2000 through February 2002. Based on preoperative spherical equivalent, the eyes were divided into a low myopia group (A) (-1.0 to -6.0 diopter [D]) and a higher myopia group (B) (> -6.01 D). Preoperative and postoperative spherical equivalent (SE), best corrected visual acuity (BCVA), and uncorrected visual acuity (UCVA) were measured and analyzed within each group. Patients had at least 2 follow-up visits, with the second visit occurring between 1 and 9 months postoperatively. RESULTS: Preoperatively, the mean SE in Group A was -3.93 D +/- 1.53 (SD) and in Group B, -8.49 +/- 1.70 D. At the final visit, the SE in Group A decreased to -0.29 +/- 0.55 D and in Group B, -1.09 +/- 0.87 D. The UCVA in Group A at the final visit was 20/20 or better in 43% of eyes and 20/40 or better in 100% of eyes. In Group B, the UCVA was 20/20 or better in 31% of eyes and 20/40 or better in 75% of eyes. In all eyes, the BCVA improved by 1 line in 16% or remained the same in 84%. No eyes lost any lines of BCVA. The SE taken at the last visit was within +/-0.5 D in 69% of all eyes and within +/-1.0 D in 82% of all eyes. The incidence of patients needing retreatment in resident-performed LASIK surgery was 3 of 44 (6.8%). CONCLUSIONS: Laser in situ keratomileusis performed by residents is a safe and effective procedure for correction of refractive error. Postoperative UCVA, refractive error, retreatment rate, and loss of BCVA were consistent with published results from nonresident surgeons. These results also exceeded the U.S. Food and Drug Administration requirements for LASIK surgery.     

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.     

Outcomes of retreatment after laser in situ keratomileusis

OBJECTIVE: To evaluate the safety and efficacy of retreatment after myopic laser in situ keratomileusis (LASIK). DESIGN: Retrospective, noncomparative case series. PARTICIPANTS: A total of 962 eyes of 566 patients underwent LASIK for up to -20.0 diopters (D) of myopia, of which 53 eyes (5.5%) were retreated. INTERVENTION: Retreatments were performed by lifting the original flap and using the Nidek EC-5000 excimer laser (Nidek Inc., Tokyo, Japan). MAIN OUTCOME MEASURES: Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BCVA), fogged manifest refraction, and complications were evaluated 6 months after retreatment. RESULTS: Overall, 53 (5.5%) of 962 eyes underwent LASIK retreatment. Before retreatment, the mean spherical equivalent (MSE) was -1.7 +/- 1.1 D (range, +0.3 to -5.0 D), UCVA ranged from 20/25 to 20/400, and BCVA ranged from 20/20 to 20/50. Six months after retreatment, the MSE was -0.09 +/- 0.29 D, 48 (90.6%) eyes were within +/-0.5 D, and all eyes were within +/-1.0 D of the attempted correction. The UCVA improved to 20/20 or better in 21 (39.6%) eyes and 20/40 or better in 51 (96.2%) eyes. The BCVA was maintained in 33 eyes (62.3%), 15 eyes (28.3%) gained 1 line or more of vision, whereas 5 eyes (9.4%) lost 1 line. All eyes had a BCVA of 20/50 or better. No retreated eye lost two or more lines of BCVA. No complications were observed. CONCLUSION: Retreatment for low amounts of residual myopia performed by lifting the original flap within the first year after surgery after myopic LASIK is safe, effective, and predictable.     

Lift-flap retreatment after laser in situ keratomileusis

PURPOSE: To demonstrate the effectiveness of lifting the flap for retreatment of undercorrected eyes after laser in situ keratomileusis (LASIK). METHODS: We reviewed the results of 11 LASIK patients (12 eyes) who underwent retreatment for residual myopia by lifting the previously cut flap. This was followed by treatment with the Summit Apex excimer laser and repositioning of the flap. Average time prior to retreatment was 5 months (range, 1 to 9 mo). Follow-up was 100% at 3 months after retreatment. RESULTS: The average preoperative spherical equivalent refraction was -8.73 D; average prior to retreatment was -2.24 D (range, -0.67 to -5.75 D). At 1 month after retreatment, average deviation from intended correction was 0.08 D; at 3 months it was -0.12 D. Eleven of 12 treated eyes (92%) had uncorrected visual acuity of 20/40 or better and 4 eyes (33%) saw 20/20 or better without correction. Six eyes (50%) were within +/- 0.50 D of intended correction at 3 months. No patients lost any lines of spectacle-corrected visual acuity. CONCLUSION: Retreatment of residual myopia after LASIK by lifting the flap appears to be effective and associated with minimal complications.     

准分子激光原位角膜磨镶术后屈光度数欠矫及回退再手术探讨

目的　探讨再次手术治疗准分子激光原位角膜磨镶术 (laserinsitukeratomileusis,LASIK)后屈光度数欠矫和回退的疗效。方法　将 1996年 3月至 1999年 7月在我院近视激光治疗中心行再次LASIK(re LASIK ,RLASIK)矫治残余近视度数患者 6 3例 (88只眼 ) ,按首次LASIK(firstLASIK ,FLASIK)术前等值球镜屈光度数分为Ⅰ组 4 1只眼 (≤ 10 0 0D)和Ⅱ组 4 7只眼 (>10 0 0D) ,分析导致再手术的因素 ;观察RLASIK术后屈光度数、裸眼视力、最佳矫正视力及手术并发症情况 ,统计术后屈光度数 <± 1 0 0D的发生率。术后随访时间 >1年。结果　在行RLASIK者中 ,FLASIK术前屈光度数>10 0 0D者超过 5 0 0 % ,同时行散光矫正术者占 73 9%。RLASIK术后Ⅰ组无屈光度数欠矫和回退现象 ,Ⅱ组存在屈光度数欠矫现象。RLASIK术后 1年 ,屈光度数 <± 1 0 0D者Ⅰ组为 6 8 3% ,Ⅱ组为5 1 1% ;全部病例RLASIK术后不同时间裸眼视力≥ 0 5者均超过 90 0 % ,最佳矫正视力较RLASIK术前下降 >2行者 8只眼 (9 0 % )。RLASIK术后Ⅱ组 3只眼 (3 4 % )发生圆锥角膜。结论　导致LASIK术后再手术的危险因素为高度近视、合并散光、个体反应差别。对于FLASIK术前屈光度数≤ 10 0 0D者 ,RLASIK的安全性、有效性、预测性及准确性均较为理想 ;对于F     

Laser in situ keratomileusis for residual myopia after photorefractive keratectomy

PURPOSE: To evaluate the efficacy and safety of laser in situ keratomileusis (LASIK) for myopic regression and undercorrection after photorefractive keratectomy (PRK). SETTING: The Eye Institute, Sydney, Australia. METHODS: Fifty eyes of 32 patients were treated by LASIK for residual myopia following primary PRK. The mean spherical equivalent refraction (SEQ) was -2.92 diopters (D) +/- 1.57 (SD) (range -0.75 to -7.88 D). The mean refractive cylinder was 0.96 +/- 0.74 D (range 0 to 3.50 D). For analysis, the eyes were divided into 2 groups: those with 0 or low corneal haze (Group 1) and those with severe corneal haze (Group 2). In Group 1, the SEQ was -1.99 +/- 0.79 D (range -0.75 to -3.75 D) and in Group 2, -3.77 +/- 1.62 D (range -0.75 to -7.90 D). The procedure was performed using the Chiron Automated Corneal Shaper and the Summit Apex Plus laser. The mean interval between PRK and LASIK was 25 months (range 9 to 59 months). The following parameters were studied before and after LASIK retreatment: SEQ, mean refractive cylinder, uncorrected visual acuity (UCVA), and best corrected visual acuity (BCVA). Complications after LASIK retreatment were evaluated. RESULTS: Six months after LASIK, the mean SEQ in all eyes was -0.65 +/- 0.86 D (range +1.50 to -3.35 D); 70.0% of eyes were within +/-1.00 D of emmetropia and the UCVA was 6/12 or better in 72.5%. The mean SEQ in Group 1 was -0.22 +/- 0.55 D (range -0.88 to -1.50 D) and in Group 2, -0.97+/- 0.92 D (range 0.12 to -3.25 D); the UCVA was 6/12 or better in 94.0% of eyes in Group 1 and in 56.0% in Group 2. No statistically significant between-group difference was found in lines of Snellen acuity lost or gained at 6 months. No eye lost more than 1 line of BCVA. CONCLUSIONS: Laser in situ keratomileusis appears to be a safe, effective, and predictable procedure for treating eyes with 0 or low haze with residual myopia after PRK. It is less predictable in eyes with severe haze.     

Laser in situ keratomileusis enhancement after photorefractive keratectomy

OBJECTIVE: To describe the safety, effectiveness, and predictability of laser in situ keratomileusis (LASIK) for correcting residual myopia after primary photorefractive keratectomy (PRK). DESIGN: A retrospective, noncomparative case series. PARTICIPANTS AND INTERVENTION: Thirty-six consecutive eyes of 30 patients underwent LASIK after primary PRK. A Multiscan Schwind excimer laser was used for LASIK enhancement. MAIN OUTCOME MEASURES: Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity, refraction, videokeratography, and complications were determined before and after LASIK retreatment. Follow-up was at least 12 months. RESULTS: Before LASIK, 11.11% of eyes showed a UCVA of 20/40 or better. This increased to 94.44% 12 months after LASIK. A UCVA of 20/25 or better was achieved in 0% before and in 72.22% after retreatment. Refraction +/-0.5 diopters (spherical equivalent) represented 0% of eyes before and 77.78% of eyes after enhancement. Before LASIK, two eyes had significant haze. Haze remained in these two eyes and appeared in another eye. CONCLUSIONS: Laser in situ keratomileusis proved to be safe and effective for treating residual myopia after PRK. Care must be taken when considering LASIK retreatment in patients with significant haze after primary PRK.     

Comparison of photorefractive keratectomy and laser in situ keratomileusis for myopia of -6 D or less using the Nidek EC-5000 laser

PURPOSE: We compared the efficacy, predictability, and safety of photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) for the surgical correction of low and moderate myopia. METHODS: A retrospective study was performed to evaluate uncorrected and spectacle-corrected visual acuity, and manifest refraction 1 year after PRK or LASIK. All procedures were done using an automatic microkeratome (Chiron Ophthalmic) and the Nidek EC-5000 excimer laser. RESULTS: PRK was performed in 75 eyes of 45 patients and LASIK in 133 eyes of 77 patients. Mean age for PRK patients was 32.8 years (range, 18 to 52 yr) and LASIK patients was 29.6 years (range, 18 to 49 yr). Mean preoperative spherical equivalent refraction for PRK patients was -3.28 D (range, -1.00 to -6.00 D) and LASIK, -3.86 D (range, -1.00 to -6.00 D). One year after surgery, mean spherical equivalent refraction for Group 1 (baseline, -1.00 to -3.00 D) PRK eyes was -0.18 +/- 0.61 D (range, -1.50 to +0.75 D) and for LASIK eyes, -0.08 +/- 0.61 D (range, -1.50 to +1.62 D), with no statistically significant difference. For Group 2 eyes (baseline, -3.25 to -6.00 D), mean spherical equivalent refraction for PRK eyes was -0.44 +/- 0.87 D (range, -2.00 to +2.12 D) and for LASIK eyes, -0.09 +/- 0.83 D (range, -1.50 to +1.75 D), with no statistically significant difference. The antilogarithm of the mean UCVA (antilogUCVA) in Group 1 for PRK was 0.79 +/- 0.21 (20/25) and for LASIK was 0.87 +/- 0.19 (20/23), with no statistically significant difference. The antilogUCVA in Group 2 for PRK eyes was 0.70 +/- 0.24 (20/28) and for LASIK eyes was 0.83 +/- 0.18 (20/24), with a statistically significant difference (0.7 vs. 0.83, P < .005). The percentage of eyes with a postoperative UCVA >20/40 in Group 1 for PRK was 91.5% (38 eyes) and for LASIK was 95% (50 eyes) (no statistically significant difference), and in Group 2 for PRK eyes, it was 82% (27 eyes) and 97.5% (78 eyes) for LASIK (statistically significant difference, P < .05). CONCLUSION: PRK and LASIK with the Nidek EC-5000 excimer laser are effective and safe for correcting low to moderate myopia, but LASIK eyes showed better results for moderate myopia in terms of uncorrected visual acuity.     

Laser in situ keratomileusis for myopia up to -11 diopters with up to -5 diopters of astigmatism with the summit autonomous LADARVision excimer laser system

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.     

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.     

Comparison of implantable contact lens and laser assisted in situ keratomileusis for moderate to high myopia

PURPOSE: To compare the results of laser assisted in situ keratomileusis (LASIK) and implantable contact lenses (ICL) in the correction of moderate/high myopia. METHODS: Five hundred fifty-nine LASIK eyes from the Davis Duehr Eye Center, Madison, WI, and 210 ICL eyes from the 14-site U.S. FDA Clinical Trial for ICL for Myopia were compared. These series were concurrently operated on with 8 to 12 D of preoperative myopia and were examined at 1 day, 1 week, 1 month, 6 months, and 1 year postoperatively. The mean baseline myopia was slightly higher in the ICL group, (ICL: -9.8 +/- 1.7 D; LASIK: -9.1 +/- 0.97 D). BSCVA, UCVA, and refractions were collected prospectively in both series. RESULTS: Every index of BSCVA, UCVA, predictability of refraction, and stability of refraction studied favored the ICL over the LASIK procedure. All but one of the indices (UCVA % 20/40 or better) were statistically significant in at least half of the time periods studied. At 6-month follow-up, both the loss of two or more lines (ICL: 0%; LASIK: 2%; p = 0.05) and gain of two or more lines (ICL: 7%; LASIK: 3%; p = 0.04) of BSCVA were better with the ICL. Similarly, efficacy outcomes with the ICL were better with predictability (attempted versus achieved +/-1.0 D) of the ICL at 90%; 76% with LASIK (p < 0.001). In this highly myopic series, UCVA 20/20 or better was 50% with ICL compared with 35% with LASIK (p < 0.001). No serious complications occurred in either series of cases. CONCLUSIONS: The ICL was safer and more effective than LASIK and appears to be a viable alternative to corneal refractive excimer surgery in the treatment of moderate to high myopia.     

Surgical outcomes of photorefractive keratectomy and laser in situ keratomileusis by inexperienced surgeons

PURPOSE: To investigate the results of photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) procedures performed by novice ophthalmologists and compare the results with those of experienced refractive surgeons. SETTING: Doheny Eye Institute, University of Southern California, Los Angeles, and Department of Ophthalmology, University of California, Irvine, California, USA. METHODS: In this retrospective case series, data were examined from the first PRK procedures by 33 consecutive ophthalmologists and the first LASIK procedures by 19 consecutive ophthalmologists. Preoperative and postoperative uncorrected visual acuity (UCVA) and best spectacle-corrected visual acuity (BSCVA), as well as intraoperative and early postoperative complications, were recorded. RESULTS: In the PRK group, 33.3% of eyes achieved a UCVA of 20/20 and 87.8%, 20/40 or better; 54.5% were within +/-0.5 diopter (D) of emmetropia and 87.8%, within +/-1.0 D. Two eyes with a preoperative spherical equivalent of greater than -11.0 D lost 2 lines of BSCVA. If eyes with low myopia (相似文献   

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.     

Photorefractive keratectomy for myopia with the Meditec MEL 70G-Scan flying spot laser

PURPOSE: To evaluate the efficacy, predictability, stability, and safety of the Meditec MEL 70G-Scan flying spot excimer laser. METHODS: One hundred thirty myopic eyes were treated with the Aesculap Meditec Mel 70G-Scan ArF flying spot excimer laser with photorefractive keratectomy (PRK). Patient groups: low myopia (Group 1) from -1.50 to -6.00 D (90 eyes), medium myopia (Group 2) from -6.10 to -9.00 D (31 eyes), high myopia (Group 3) from -9.10 to -14.00 D (9 eyes). RESULTS: At 12 months in the low myopia group, uncorrected visual acuity (UCVA) of 20/40 or better was achieved in 95.5% (86 eyes), 20/20 or better in 77.7% (70 eyes); 2.2% (two eyes) lost two or more lines of best spectacle-corrected visual acuity (BSCVA); 73.3% (66 eyes) were within +/-0.50 D of the target correction and 98.8% (89 eyes) were within +/-1.00 D. In the medium myopia group, UCVA of 20/40 or better was achieved in 74.2% (23 eyes), 20/20 or better in 25.8% (eight eyes); 3.2% (one eye) lost two lines, 61% (19 eyes) were within +/-0.50 D of desired correction and 83.8% (26 eyes) were within +/-1.00 D. In the high myopia group, UCVA of 20/40 or better was achieved in 22.2% (two eyes); 20/25 or better in 11.1% (one eye); none of the eyes achieved 20/20 UCVA; 22.2% (two eyes) lost two lines of BSCVA; 44.4% (four eyes) were within +/-0.50 D and 66.6% (six eyes) were within +/-1.00 D of the target correction. Refractive stability was achieved between 3 and 6 months. Increased intraocular pressure was detected overall in 7.69%. CONCLUSIONS: The results of predictability, safety, and efficacy in low and medium myopia with the Meditec MEL 70G-Scan flying spot excimer laser were good, but poorer predictability, regression, and a significant loss of BSCVA were observed in the high myopia group.     

Safety and predictability of laser in situ keratomileusis enhancement by flap reelevation in high myopia

PURPOSE: To evaluate the safety and predictability of laser in situ keratomileusis (LASIK) retreatment following primary procedures for high myopia and astigmatism. SETTING: Corneal Diseases and Excimer Laser Research Unit, Department of Ophthalmology, University of Dundee, Dundee, United Kingdom. METHODS: This prospective observational study of retreatment comprised a cohort of 109 eyes having primary LASIK for high myopia and astigmatism with a spherical equivalent (SE) of -9.70 diopters (D) +/- 4.06 (SD). Twenty-four eyes (22%) with an initial myopic SE of -9.83 +/- 3.50 D, a comparable subset of the entire group (P < .05), had retreatment for residual myopia (-3.02 +/- 2.17 D) to improve uncorrected visual acuity (UCVA) by reelevating the corneal flap and ablating the stromal bed. RESULTS: The mean follow-up after retreatment was 12.8 +/- 5.1 months (range 1.5 to 24 months; 19 eyes >/=6 months, 13 eyes > or = 12 months). The mean myopic SE was reduced to +0.53 +/- 0.62 D at 1 week, +0.05 +/- 0.50 D at 1 month, +0.30 +/- 0.50 D at 6 months, and +0.18 +/- 0.42 D at the latest follow-up, 12.8 months. At the latest review, 62% of eyes were within +/-0.50 D of emmetropia and 100% were within +/-1.00 D. The mean refraction did not alter statistically between 1 week and subsequent times. The mean UCVA improved from 6/30 prior to retreatment to 6/9 at the latest follow-up. Uncorrected visual acuity of 6/6 or better, 6/9 or better, and 6/12 or better was achieved by 33.0%, 75.0%, and 95.8% of eyes, respectively. No significant complications that led to a loss of best corrected visual acuity were encountered, although retreatment procedures were more uncomfortable than primary procedures and self-limiting; epithelial ingrowth that did not threaten vision was common, and 2 patients complained of nighttime visual symptoms. CONCLUSIONS: Retreatment of residual myopia by reelevating the flap was relatively safe and predictable, with a low risk of sight-threatening complications. However, longer term studies may be required to detect late complications.     

Laser in situ keratomileusis enhancement for consecutive hyperopia after myopic overcorrection.

PURPOSE: To assess the efficacy, predictability, and safety of laser in situ keratomileusis (LASIK) for the treatment of consecutive hyperopia after myopic LASIK. SETTING: Stanford University School of Medicine, Stanford, California, USA. METHODS: In a retrospective study, 36 eyes of 30 patients with consecutive hyperopia after myopic LASIK had LASIK retreatment using the VISX S2 excimer laser. Primary outcome variables including uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), manifest refraction, complications, and vector analysis were evaluated preoperatively and 1 day and 3 months postoperatively. RESULTS: The mean spherical equivalent decreased from +1.52 diopters (D) +/- 0.55 (SD) (range +0.63 to +2.63 D) preoperatively to -0.10 +/- 0.52 D (range -1.25 to +1.50 D) 3 months after retreatment. The UCVA was 20/20 or better in 24 eyes (66.7%) and 20/40 or better in 34 eyes (94.4%). Twenty eyes (55.5%) were within +/-0.5 D of the intended correction and 34 eyes (94.4%), within +/-1.0 D. No eye lost 2 or more lines of BSCVA. One eye (2.8%) developed diffuse lamellar keratitis that resolved without sequelae, and 2 eyes (5.6%) developed nonprogressive epithelial ingrowth that did not require removal. CONCLUSIONS: Laser in situ keratomileusis retreatment for consecutive hyperopia following myopic LASIK was an effective, predictable, and safe procedure. Long-term follow-up is needed to assess stability.     

Femtosecond laser in situ keratomileusis after radial keratotomy

PURPOSE: To assess the safety, efficacy, and predictability of femtosecond laser in situ keratomileusis (LASIK) in eyes with previous radial keratotomy (RK). SETTING: Hospital Virgen del Consuelo de Valencia, Valencia, and Vissum Instituto Oftalmológico de Alicante, Alicante, Spain. METHODS: This prospective study comprised 11 eyes of 7 patients with residual low myopia after previous RK who had surgery with the IntraLase femtosecond laser (IntraLase Corp.) and the Star 2 excimer laser (Visx, Inc.). Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), defocus equivalent, refraction, flap thickness, flap diameter, and intraoperative complications were evaluated over a minimum 6-month follow-up. RESULTS: Although the RK incisions opened in all eyes when the flap was lifted, LASIK was successfully completed in all cases. Mean flap thickness was 119 microm +/- 13 (SD). There were no cases of slipped flaps, microstriae, or epithelial ingrowth. Defocus equivalent was reduced from a mean of 2.51 +/- 0.62 diopters (D) to 0.52 +/- 0.28 D; 7 eyes (63.6%) were within +/-0.50 D, and 11 eyes (100%) were within +/-1.00 D. All eyes had 20/40 or better UCVA, although 2 eyes (18.1%) lost 1 line of BSCVA. CONCLUSIONS: The femtosecond laser was safely used to create thin LASIK flaps in eyes with previous RK. An increased postoperative inflammatory response may explain the loss of BSCVA in some cases. Efficacy and predictability of the procedure were comparable to those of LASIK after RK with mechanical microkeratomes.     

Myopic and hyperopic laser in situ keratomileusis retreatments: indications, techniques, limitations, and results

PURPOSE: To assess the efficacy of myopic and hyperopic laser in situ keratomileusis (LASIK) retreatment procedures. SETTING: Mater Private Hospital, Dublin, Ireland. METHODS: Retreatment was defined as either lifting the previously created flap or when this was not possible, cutting a new flap. Fifty-six patients were retreated, 17 with hyperopia (Group 1) and 39 with myopia (Group 2). The mean preoperative spherical equivalent in Group 1 was +3.79 diopters (D) +/- 1.53 (SD) (range +1.75 to +8.12 D) and in Group 2, -5.46 +/- 2.87 D (range -0.38 to -15.25 D). RESULTS: The indications for retreatment were undercorrection, decentration, epithelial ingrowth, and central island. Postoperatively, the mean spherical equivalents in Groups 1 and 2 were +1.11 +/- 2.02 D (range -1.75 to +5.50 D) and -1.02 +/- 2.20 D (range +4.75 to -9.00 D), respectively. In Group 1, the uncorrected visual acuity (UCVA) was 6/12 or better in 5.8% preoperatively and in 35% postoperatively. In Group 2, the UCVA was 6/12 or better in 5.1% preoperatively and in 59.0% postoperatively. Although 29% of the hyperopic eyes and 8% of the myopic eyes lost 1 Snellen line of best corrected visual acuity (BCVA), there was an improvement (of 1 or more lines) in BCVA in 12% and 49%, respectively. In cases that were decentered preoperatively, the postoperative optical zone ablation centration was better in 85.7% of Group 1 eyes and 61.5% of Group 2 eyes. Corneal complications following retreatment included peripheral scarring, epithelial ingrowth, Bowman's folds, and keratectasia. CONCLUSIONS: Both myopic and hyperopic retreatments resulted in a stable refractive outcome. Myopic retreatments were superior to hyperopic retreatments in both efficacy and safety.     

Laser in situ keratomileusis for different degrees of myopia

PURPOSE: To determine the efficacy, predictability, stability and safety of laser in situ keratomileusis (LASIK) in treating patients with different degrees of myopia. METHODS: We enrolled 386 eyes of 200 consecutive patients who underwent LASIK and divided them into four groups according to their degree of preoperative spherical equivalent (SE). Group 1 eyes ranged between - 1.00 and - 3.99 dioptres (D) (low myopia). Group 2 eyes ranged between - 4.00 and - 5.99 D (moderate myopia). Group 3 eyes ranged between - 6.00 and - 9.99 D (high myopia). Group 4 eyes were over - 9.99 D (extreme myopia). Follow-up was at 1 day, 1 week and 1, 3, 6, 12 and 18 months postoperatively. RESULTS: Our study included 386 eyes of 200 patients with SE ranging from - 3.00 to - 16.00 D (mean - 7.14 +/- 2.87 D). All eyes were seen at 1 day postoperatively. A total of 360 eyes (93%) were examined at 1 week, 330 eyes (85%) at 1 month, 281 eyes (73%) at 3 months, 247 eyes (64%) at 6 months, 199 eyes (52%) at 12 months and 142 eyes (37%) at 18 months. The postoperative data from 1 day to 12 months were used because of the low follow-up rate at 18 months postoperatively. Group 1 consisted of 30 eyes. The mean SE was - 3.52 +/- 0.43 D preoperatively and - 0.40 +/- 0.58 D at 1 month, - 0.46 +/- 0.60 D at 6 months and - 0.42 +/- 0.50 D at 12 months postoperatively. Uncorrected visual acuity (UCVA) was 20/40 or better in 95% of eyes at 1 day and in 100% of eyes at 6 and 12 months postoperatively. Group 2 consisted of 151 eyes. The mean SE was - 5.36 +/- 0.67 D preoperatively and - 0.54 +/- 0.78 D at 1 month, - 0.56 +/- 0.90 D at 6 months and - 0.55 +/- 0.82 D at 12 months postoperatively. Uncorrected VA was 20/40 or better in 95% of eyes at 1 day and in 100% of eyes at 6 and 12 months postoperatively. Group 3 consisted of 167 eyes. The mean SE was - 8.15 +/- 0.94 D preoperatively and - 0.58 +/- 0.90 D at 1 month, - 0.67 +/- 1.00 D at 6 months and - 0.64 +/- 0.95 D at 12 months postoperatively. Uncorrected VA was 20/40 or better in 90% of eyes at 1 day and in 98% of eyes at 6 and 12 months postoperatively. Group 4 consisted of 38 eyes. The mean SE was - 11.09 +/- 1.10 D preoperatively and - 1.25 +/- 1.20 D at 1 month, - 1.13 +/- 1.30 D at 6 months and - 1.20 +/- 1.25 D at 12 months postoperatively. Uncorrected VA was 20/40 or better in 78% of eyes at 1 day, in 94% at 6 months and in 90% at 12 months postoperatively. Intraoperative complications (free cap) occurred in two eyes and postoperative complications were observed in three eyes, making the total complications rate 1.29% (5/386). Seven eyes lost one Snellen line of BCVA, five lost two lines and two lost more than two lines (total: 3.64%, 14/386). CONCLUSION: In conclusion, LASIK is effective, predictable and safe for correcting myopia but is more accurate for correcting myopia up to -10.00 D. With more improvement in algorithms and ablation profile, we believe that LASIK can offer better results for higher myopia.