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Purpose: To describe a new strategy for intraocular lens (IOL) power calculations after laser in situ keratomileusis (LASIK), determine the accuracy of the method, and compare the results with those of previously described techniques. Setting: Emory Eye Center, Atlanta, Georgia, USA. Methods: This retrospective comparative series compared eyes having cataract extraction after laser in situ keratomileusis (LASIK) and eyes having cataract extraction without previous surgery (control group) from January 1997 to December 2005. In the LASIK group, 2 strategies were used to determine the appropriate corneal curvature (K) value for IOL calculation: (1) the nonconsensus method and (2) the consensus-K technique. Postoperative outcomes were compared and included refraction, deviation from target refraction, and deviation from the ideal K or ideal IOL value for several techniques. Results: There were 43 LASIK eyes (14 nonconsensus and 29 consensus K) and 50 control eyes. The mean absolute deviation from target refraction in the nonconsensus group (1.47 diopters [D]) was significantly higher than that in the consensus-K group (0.52 D) (P = .02) or control group (0.44 D) (P = .01); the mean was not statistically different between the consensus-K group and the control group (P = .5). Compared with values with the consensus-K technique, the absolute deviation from back-calculated K values was significantly higher (P<.05) with all other K-generating methods tested except the classic refractive history method (0.56 D versus 0.65 D) (P = .4). When compared with the IOL value generated using the consensus-K technique, the absolute deviation from back-calculated IOL values was significantly higher for all other methods (P<.05). Conclusions: The consensus-K technique generated refractive outcomes similar to those in the control group and was better than with all other K- or IOL-generating techniques except the classic refractive history method. The consensus method showed less variability and higher predictability than all other methods tested. [Copyright &y& Elsevier]

Purpose: To analyze the occurrence of epithelial defects during primary laser in situ keratomileusis (LASIK) and identify predictive preoperative risk factors. Setting: Department of Ophthalmology, Emory University, Atlanta, Georgia, USA. Methods: The records of primary LASIK cases performed between January 2001 and May 2002 were retrospectively evaluated. Information abstracted included patient sex, age, and preoperative refraction (spherical equivalent) and the excimer laser used (Nidek EC-5000 or Alcon LADARVision). The primary outcome measure was the rate of intraoperative epithelial defect formation. Results: A total of 6984 primary LASIK cases were analyzed; these included 6067 cases with myopia and 917 cases with hyperopia. In all cases, the flaps were created with a Hansatome microkeratome (Bausch & Lomb). Most cases (75.6%) were performed with the Nidek EC-5000 excimer laser; all hyperopia cases were performed with the LADARVision laser. Overall, 647 cases (9.3%) had epithelial defects. There were 323 cases (9.5%) of epithelial defect in men and 319 (9.0%) in women (P = .4). The rate of epithelial defect increased with age; 124 (4.1%) occurred in patients younger than 40 years, and 523 (13.2%) occurred in patients older than 40 years (P<.0001). One hundred sixty cases (17.3%) were in hyperopic eyes and 487 cases (8.0%), in myopic eyes (P<.0001). Multivariate analysis of LADARVision cases showed that age older than 40 years and hyperopia were risk factors for epithelial defect (odds ratio 2.7 and 1.7, respectively; P<.0001 and P = .00002, respectively), while sex was not. Conclusion: Risk factors for epithelial defect formation during LASIK included increasing patient age, especially older than 40 years, and preoperative hyperopia. [Copyright &y& Elsevier]

Purpose: To compare early visual outcomes after wavefront-optimized advanced surface ablation (ASA) with those after wavefront-optimized LASIK. Design: Retrospective comparative series. Participants: One hundred thirty-six eyes undergoing ASA and 136 preoperative refraction–matched eyes undergoing LASIK from June 2004 through October 2005. Methods: Database review of preoperative characteristics, including patient age, gender, refraction, and central corneal pachymetry; perioperative information, including type of surgery, flap thickness (for LASIK cases), ablation depth, and residual stromal bed thickness; and postoperative information, including uncorrected visual acuity (UCVA) at 1 day, 1 week, 2 weeks, and 3 months, refraction at 3 months, and complications. All ASA patients had topical mitomycin C applied intraoperatively. Main Outcomes Measures: Postoperative UCVA, best spectacle-corrected visual acuity (BSCVA), spherical equivalent (SE) refraction, speed of visual recovery, and postoperative complications. Results: Surface ablation patients were younger (35.4 years vs. 39.8 years, P = 0.0002) and had thinner corneas (514 μm vs. 549 μm, P<0.0001) preoperatively. Average UCVA was significantly better after LASIK at 1 day (20/26.8 vs. 20/50.4, P<0.0001) and 2 weeks (20/24.4 vs. 20/33.3, P = 0.0002) postoperatively. However, by 3 months postoperatively, UCVA was better after ASA (20/20.8 vs. 20/22.7, P = 0.05), and 81.5% of patients achieved 20/20 or better UCVA after ASA, compared with 70.5% after LASIK (P = 0.05). More ASA eyes had postoperative UCVA that achieved or surpassed preoperative BSCVA than LASIK eyes (66% vs. 41.6%, P<0.0001). There were 53 patients who underwent bilateral simultaneous ASA. By 1 week, 87.5% had 20/40 or better UCVA in at least one eye and 62.5% had 20/40 or better UCVA in both eyes. By 2 weeks, 86.8% had 20/40 or better UCVA in one eye and 82.6% had 20/40 or better UCVA in both eyes. Conclusion: Initial visual recovery is more rapid after LASIK; however, by 3 months postoperatively UCVA and SE refractions were better after ASA. Advanced surface ablation is an effective alternative to LASIK, and based on early visual recovery, bilateral simultaneous surface ablation is a reasonable alternative to sequential surgery for the majority of patients. [Copyright &y& Elsevier]

Purpose: To compare 2 methods of calculating residual stromal bed (RSB) thickness after repeat LASIK, to determine which method generates more conservative RSB thickness estimates, and to determine any factors related to the discrepancy between these 2 calculation methods. Design: Retrospective nonrandomized comparative trial. Participants: Seventy-nine patients (one eye per patient) undergoing primary LASIK and 2 repeat procedures (second and third LASIK) from 1998 to 2002. Methods: We compared calculated RSB thickness after second and third LASIK using either original corneal thickness (CT) minus flap thickness and all ablations (original CT method) or pre-enhancement CT minus flap thickness and enhancement ablation (repeat CT method). Main outcomes measures: Differences in calculated RSB thickness after second and third LASIK by each method. Results: Calculated RSB thickness averaged 329 μm by the repeat CT method compared with 305 μm by the original CT method after second LASIK (mean difference, 24 μm; P<0.0001) and 320 μm by the repeat CT method compared with 289 μm by the original CT method after third LASIK (mean difference, 31 μm; P<0.0001). After second LASIK, for 54% of eyes the repeat CT method was greater by ≥20 μm, and for 19% of eyes it was greater by ≥40 μm. After third LASIK, for 67% of eyes the repeat CT method was greater by ≥20 μm, and for 26% of eyes it was greater by ≥40 μm. The repeat CT method gave greater RSB thickness values than the original CT method in 73 of 79 eyes (92%) after second LASIK and in 72 of 79 eyes (91%) after third LASIK. The difference between the 2 methods was not associated with age, gender, initial preoperative refractive error, or refractive error before repeat LASIK. Conclusion: Using original preoperative CT measurements provides a more conservative and thus safer approach than using CT measurements obtained before repeat LASIK to calculate RSB thickness after repeat LASIK. [Copyright &y& Elsevier]

Objective: To compare visual outcomes in eyes undergoing aberrometry-guided (InterWave) LASIK with those in eyes undergoing standard LASIK treatment based upon refractive measures.Design: Single-center, comparative, interventional, consecutive case series.Participants: Four hundred two consecutive eyes undergoing LASIK were analyzed retrospectively. One group, 106 eyes undergoing primary LASIK and 224 eyes undergoing LASIK enhancement, was treated with standard LASIK treatment using a 5.5-mm optical zone, 1.5-mm transition zone laser with the settings determined by manifest refraction. The second group, 44 untreated (primary) eyes and 28 previously treated (enhancement) eyes, received a multipass, multistage treatment in which the laser settings for each stage were determined by aberrometry measurements. Eyes with desired monovision (undercorrected) outcome and preoperative hyperopia were excluded from the study.Intervention: An aberrometry-guided laser treatment (InterWave LASIK) was compared with the standard LASIK treatment based upon the manifest refraction.Main outcome measures: Uncorrected visual acuity (VA), manifest refraction, best spectacle-corrected VA (BSCVA), severity of halos, and root mean square (RMS) retinal blur area measured at 3 months postoperatively.Results: Three months postoperatively there was no difference in uncorrected VA, BSCVA, refraction, or RMS retinal blur areas for pupil sizes of 3.5 mm between eyes treated by InterWave and those treated by standard LASIK. However, InterWave LASIK reduced the retinal blur area by 48% (P<0.0103) and 58% (P<0.0004) in primary cases and 43% (P<0.0430) and 74% (P<0.0271) in enhancement cases, respectively, for pupil sizes of 4.5 and 6.5 mm relative to standard LASIK treatments. Patients undergoing InterWave-guided treatment reported less severity of halo (0.37 vs. 0.98 [P<0.016] for primary cases and 0.35 vs. 0.73 [P<0.04] for enhancement cases).Conclusion: InterWave LASIK achieved acuity and refractive results equivalent to those of standard LASIK treatment based upon refraction, but resulted in superior quality mesopic vision. [Copyright &y& Elsevier]

: ObjectiveTo report cases of Avellino corneal dystrophy (ACD) exacerbated by LASIK for myopia.: DesignRetrospective, noncomparative, interventional case series and review of the literature.: ParticipantsSeven patients.: InterventionSix patients with exacerbation of granular corneal deposits after LASIK were examined for TGFBI mutations by polymerase chain reaction sequencing of DNA. One previously reported patient who was heterozygous for the ACD gene was followed up for 16 months after mechanical removal of granular deposits from the interface after LASIK.: Main outcome measuresSlit-lamp examination, visual acuity, manifest refraction, and DNA sequencing analysis.: ResultsAll patients were heterozygous for the Avellino dystrophy gene. Corneal opacities appeared 12 months or more after LASIK. Best spectacle-corrected visual acuity decreased as the number and density of the opacities increased. One patient underwent mechanical removal of granules from the interface and had a severe recurrence within 16 months. Another patient had removal of the granules from the interface with PTK, followed by treatment with topical mitomycin C. In this patient, the cornea has remained relatively clear for 6 months.: ConclusionsLaser in situ keratomileusis increases the deposition of visually significant corneal opacities and is contraindicated in patients with ACD. Mechanical removal of the material from the interface does not prevent further visually significant deposits. Mitomycin C treatment, in conjunction with surgical removal of opacities, may be an effective treatment. [Copyright &y& Elsevier]