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Purpose: To evaluate prospectively the clinical outcomes of topography-guided laser in situ keratomileusis (LASIK) surgery performed with Contoura Vision using the Wavelight excimer laser and planned with the Phorcides Analytical Engine., Setting: Four clinical practices in the U.S., Design: Prospective single-arm interventional study., Methods: 130 eyes of 65 patients with myopia or myopic astigmatism were enrolled in a prospective study of visual and refractive outcomes after treatment with Contoura Vision using the Wavelight EX500 excimer laser to achieve optimal distance vision. At 3 months postoperatively, uncorrected distance visual acuity (UDVA), manifest refraction, and corrected distance visual acuity (CDVA) were measured and compared with previously published studies., Results: At 3 months postoperatively, 100%, 89%, and 28% of eyes achieved UDVA of 20/20, 20/15, and 20/12.5 or better, respectively. 92% of eyes had postoperative UDVA equal to or better than their preoperative CDVA. Postoperative CDVA was equal to, 1 line better, or 2 lines better than the preoperative CDVA in 53%, 40%, and 6% of eyes, respectively. Only 1 eye lost 1 line of CDVA, and no eyes lost more than 1 line of CDVA. A statistically significant decrease was noted in subjective visual complaints, including glare, halos, difficulty driving at night, reading difficulty, starbursts, fluctuation in vision, and light sensitivity., Conclusions: The Phorcides Analytical Engine can be used to optimize visual outcomes for the correction of myopia and myopic astigmatism., (Copyright © 2022 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)

Purpose: To study eyes with 20/10 uncorrected distance visual acuity (UDVA) 3 months and 12 months after topography-guided LASIK for myopia and myopic astigmatism, and to identify factors predictive of this excellent level of visual acuity., Setting: Nine practices in the USA., Design: Prospective unmasked study of safety and effectiveness., Methods: The percentage of eyes with UDVA of 20/10 or better at 3 months and 12 months after topography-guided laser in situ keratomileusis (LASIK) with the Contoura Vision excimer laser in a U.S. Food and Drug Administration clinical trial was compared, and possible contributing factors were investigated., Results: Preoperatively, only 1% of eyes had 20/10 corrected distance visual acuity (CDVA). Postoperatively, 7.0% of eyes had 20/10 or better UDVA at 3 months, and this number increased to 16% at 12 months (odds ratio, 2.48; 95% confidence interval, 1.33-4.61). The lower preoperative corneal astigmatism and postoperative refractive cylinder correlated with better postoperative UDVA and CDVA, respectively (P < .01 in all cases). The postoperative UDVA correlated with the postoperative CDVA (P < .01)., Conclusion: The number of eyes with UDVA of 20/10 increases significantly between 3 months and 12 months after topography-guided LASIK and correlates with better postoperative CDVA. Eyes with lower preoperative corneal astigmatism are more likely to achieve 20/10 or better UDVA postoperatively. A significant improvement in the number of eyes with 20/10 or better from 3 months to 12 months after LASIK might be unique to topography-guided treatment., (Copyright © 2018 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the effect of riboflavin-ultraviolet (UV)-A corneal crosslinking (CXL) without epithelial removal on ectatic corneal disease., Setting: Woolfson Eye Institute, Atlanta, Georgia, USA., Design: Prospective observational study., Methods: Patients were treated with a new riboflavin formulation without epithelial removal, then exposed to UV light (365 nm) at 4 mW/cm 2 with on-off cycling for 30 minutes. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, maximum corneal curvature (maximum keratometry [Kmax]), total higher-order aberrations (HOAs), and coma were measured at 3, 6, 12, and 24 months postoperatively. Progression was defined as an increase of more than 1 diopter (D) in Kmax and loss of more than 1 line of CDVA., Results: Five hundred twelve eyes of 308 patients with keratoconus or forme fruste keratoconus and 80 eyes of 55 patients with ectasia after laser in situ keratomileusis (LASIK) were treated with the new riboflavin formulation without epithelial removal; 229 patients received bilateral treatments, 95 of which were simultaneous. The mean UDVA and CDVA improved by 1 to 1.5 Snellen lines at 1 and 2 years postoperatively (P < .0001). Mean Kmax decreased by 0.48 D at 2 years postoperatively (P = .0002). Mean total HOAs and coma decreased by 36% (P < .0001) and 37% (P = .0002), respectively, at 2 years postoperatively. Kmax decreased more than 1 D in three times as many eyes as it increased more than 1 D (P < .0001). No eyes progressed, and there was no loss of effect between 1 and 2 years postoperatively. No vision-threatening events were observed. Pain typically resolved within 24 hours, and visual acuity returned to preoperative levels in 1 to 2 days., Conclusion: Epithelium-on CXL using this new protocol halted the progression of keratoconus and ectasia after LASIK. It was safer and provided more rapid visual recovery than CXL with epithelial removal, allowing routine bilateral, simultaneous treatment., (Copyright © 2018 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare the corneal stromal riboflavin concentration and distribution using 2 transepithelial corneal crosslinking (CXL) systems., Setting: Absorption Systems, San Diego, California, USA., Design: Experimental study., Methods: The stromal riboflavin concentration of 2 transepithelial CXL systems was compared in rabbit eyes in vivo. The systems were the Paracel/Vibex Xtra, comprising riboflavin 0.25% solution containing TRIS and ethylenediaminetetraacetic acid and an isotonic solution of riboflavin 0.25%, (Group 1) and the CXLO system (Group 2). Manufacturers' Instructions For Use were followed. The intensity of riboflavin fluorescence by slitlamp observation 10, 15, and 20 minutes after instillation was graded on a scale of 0 to 5. The animals were humanely killed and the corneal stromal samples analyzed with liquid chromatography and mass spectrometry., Results: The mean riboflavin fluorescence intensity grades in Group 1 (4 eyes) were 3.8, 4.8, and 4.8 at 10, 15, and 20 minutes, respectively. The mean grades in Group 2 (3 eyes) were 2.0, 2.3, and 2.0, respectively. The riboflavin distribution was uniform in Group 1 but not in Group 2. The mean riboflavin concentration by liquid chromatography and mass spectrometry was 27.0 μg/g stromal tissue in Group 1 and 6.7 μg/g in Group 2. A stromal riboflavin concentration theoretically adequate for CXL, 15 μg/g, was achieved in all eyes in Group 1 and no eyes in Group 2. Slitlamp grading correlated well with liquid chromatography and mass spectrometry concentration (R 2  = 0.940)., Conclusions: The system used in Group 1 produced corneal riboflavin concentrations that were theoretically adequate for effective transepithelial CXL (≥15 μg/g), while the system in Group 2 did not. Slitlamp grading successfully estimated the corneal riboflavin concentration and can be used to ensure an adequate concentration of riboflavin in the cornea for transepithelial CXL., (Copyright © 2018 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the safety and effectiveness of topography-guided custom ablation treatment (T-CAT) to correct myopia and myopic astigmatism with laser in situ keratomileusis (LASIK)., Setting: Nine clinical sites in the USA., Design: Prospective observational nonrandomized unmasked study., Methods: The study comprised patients aged 18 to 65 years old with myopia or myopic astigmatism with a manifest refraction spherical equivalent (MRSE) up to -9.0 diopters (D) and astigmatism of 6.0 D or less. Patients with previous refractive surgery or abnormal topography were excluded. Corneal topographies were obtained using the Allegro Topolyzer, and laser treatment was delivered with the Allegretto Wave Eye-Q excimer laser system. Visual outcomes were evaluated postoperatively at 1 day, 1 week, and 1, 3, 6, 9, and 12 months., Results: The clinical trial enrolled 212 patients (249 eyes). The T-CAT procedure significantly reduced the MRSE and cylinder, with stability of outcomes evident from 3 to 12 months after surgery. Compared with the preoperative corrected distance visual acuity (CDVA), the postoperative uncorrected distance visual acuity (UDVA) improved by 1 line or more in 30% of eyes and the postoperative UDVA was at least as good as the preoperative CDVA in 90% of eyes. Most visual symptoms improved after T-CAT. There were no significant treatment-related adverse events or loss of vision., Conclusion: The T-CAT procedure performed with the diagnostic device and the refractive excimer laser system safely and effectively achieved predictable refractive outcomes and reduced visual symptoms with stable results through 12 months., Financial Disclosure: Dr. Stulting is a paid consultant to Alcon Laboratories, Inc., and was a medical monitor for the U.S. Food and Drug Administration (FDA) clinical trial. Dr. Fant is president of Clinical Research Consultants, Inc. (CRC), the clinical and regulatory consulting group that sponsored the FDA clinical trial. Dr. Fant and CRC were supported by Alcon Laboratories, Inc., (Copyright © 2016 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To assess the effect of preoperative topical nonsteroidal antiinflammatory drugs (NSAIDs) on postoperative pain after laser-assisted subepithelial keratectomy (LASEK) and to investigate their mechanism., Setting: Severance Eye Hospital and Saeyan Eye Clinic, Seoul, South Korea., Design: Prospective randomized clinical trial., Methods: Participants in 2 related studies were assessed. Study 1 comprised patients scheduled for bilateral LASEK (Group 1) who were randomized to receive an NSAID in 1 eye and a placebo in the fellow eye 30, 20, and 10 minutes before LASEK. Postoperative pain, glare, tearing, and irritation were assessed using a visual analog scale. Study 2 comprised healthy subjects (Group 2) who were randomly divided into subgroups. The participants in these subgroups were randomized to receive ketorolac tromethamine 0.5% in 1 eye and placebo (ofloxacin 0.3%) in the fellow eye (Group 2A), proparacaine hydrochloride 0.5% in 1 eye and placebo in the fellow eye (Group 2B), or ketorolac tromethamine 0.5% in 1 eye and placebo in the fellow eye, followed 10 minutes later by 1 drop of proparacaine hydrochloride 0.5% in both eyes (Group 2C). In all 3 groups, corneal sensitivity was measured after 1, 2, and 6 hours., Results: The mean postoperative pain score in the NSAID-pretreated eye was statistically significantly lower than in the placebo-pretreated eye 6, 12, and 24 hours postoperatively (P < .05). The mean corneal sensitivity was statistically significantly lower in the NSAID-treated eye than in the placebo-treated eye at 1 and 2 hours in Groups 2A and 2C (P < .05)., Conclusion: Preoperative administration of topical NSAIDs before LASEK effectively reduces postoperative pain., Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned., (Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To study the effect of flap thickness on visual acuity and refractive outcomes after laser in situ keratomileusis (LASIK) using 2 blade types with a mechanical microkeratome., Setting: Emory Vision, Atlanta, Georgia, USA., Methods: This retrospective analysis was of LASIK cases performed between January 2005 and June 2006 using an Amadeus I microkeratome and an ML7090 CLB blade (blade A) or a Surepass blade (blade B). Outcomes analyzed included flap thickness, uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction spherical equivalent (MRSE), the enhancement rate, and surgical complications 3 months postoperatively., Results: Two hundred sixty-three eyes of 153 patients were analyzed; blade A was used in 158 eyes and blade B, in 105 eyes. The mean flap thickness was significantly thinner with blade A than with blade B (107 microm +/- 12 [SD] versus 130 +/- 20 microm) (P<.0001). There was no overall correlation with either blade between flap thickness and UDVA, CDVA, or MRSE (all r<0.2). At 3 months, there was no statistically significant difference in UDVA, CDVA, or MRSE between the 2 blade groups at 3 months (all P > .10), and there was no difference in the complication rates., Conclusion: Flap thickness did not affect visual or refractive outcomes with a mechanical microkeratome with either blade type., ((c) 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare visual acuity and higher-order aberrations (HOAs) after wavefront-guided and wavefront-optimized laser in situ keratomileusis (LASIK)., Methods: This retrospective study comprised refraction-matched myopic eyes that had wavefront-guided (Visx Star S4 laser) or wavefront-optimized (WaveLight Allegretto Wave laser) LASIK targeted for emmetropia. Preoperative and postoperative manifest refraction spherical equivalent (MRSE), uncorrected (UDVA) and corrected (CDVA) distance visual acuities, and preoperative and postoperative HOAs were compared., Results: Preoperatively, there were no significant differences between the wavefront-guided and wavefront-optimized groups in age, sex, corneal thickness, MRSE, or HOAs (all P>.05). The mean MRSE was -2.88 diopters (D) +/- 2.6 (SD) and -2.96 +/- 2.6 D, respectively, preoperatively and -0.01 +/- 0.25 D and -0.02 +/- 0.33 D, respectively, postoperatively; 96% of all eyes were within +/-0.50 D of emmetropia postoperatively. There were no differences in UDVA, CDVA, MRSE, or HOAs between groups (all P>.05). The UDVA was 20/20 or better in 85% of eyes in the wavefront-guided group and 86% of eyes in the wavefront-optimized group. All eyes had 20/25 or better CDVA postoperatively; no eye lost 2 lines of CDVA. Fourteen eyes were converted from wavefront-guided to wavefront-optimized treatment because of poor limbal ring alignment (8 eyes), a wave scan not consistent with the manifest refraction (5 eyes), and no iris registration (1 eye)., Conclusions: Wavefront-guided LASIK and wavefront-optimized LASIK produced equivalent visual outcomes and no differences in HOAs. Wavefront-guided treatment could not be performed in many eyes because of difficulties during wavefront measurement., (Copyright 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To analyze the reasons for patient dissatisfaction after phacoemulsification with multifocal intraocular lens (IOL) implantation and the outcomes after intervention., Setting: Emory Eye Center, Atlanta, Georgia, USA., Methods: This retrospective review comprised eyes of patients dissatisfied with visual outcomes after multifocal IOL implantation. Outcomes analyzed included type of visual complaint, treatment modality for each complaint, and degree of clinical improvement after intervention., Results: Thirty-two patients (43 eyes) reported unwanted visual symptoms after multifocal IOL implantation, including in 28 eyes (65%) with an AcrySof ReSTOR IOL and 15 (35%) with a ReZoom IOL. Thirty patients (41 eyes) reported blurred vision, 15 (18 eyes) reported photic phenomena, and 13 (16 eyes) reported both. Causes of blurred vision included ametropia (12 eyes, 29%), dry eye syndrome (6 eyes, 15%), posterior capsule opacification (PCO) (22 eyes, 54%), and unexplained etiology (1 eye, 2%). Causes of photic phenomena included IOL decentration (2 eyes, 12%), retained lens fragment (1 eye, 6%), PCO (12 eyes, 66%), dry-eye syndrome (1 eye, 2%), and unexplained etiology (2 eyes, 11%). Photic phenomena attributed to PCO also caused blurred vision. Thirty-five eyes (81%) had improvement with conservative treatment. Five eyes (12%) did not have improvement despite treatment combinations. Three eyes (7%) required IOL exchange., Conclusions: Complaints of blurred vision and photic phenomena after multifocal IOL implantation were effectively managed with appropriate treatment. Few eyes (7%) required IOL exchange. Neodymium:YAG capsulotomy should be delayed until it has been determined that IOL exchange will not be necessary.

Purpose: To determine which of 3 methods for measuring preoperative refractive error yields the best refractive outcomes after wavefront-guided (Visx Star S4) or wavefront-optimized (WaveLight Allegretto Wave) excimer laser in situ keratomileusis (LASIK)., Setting: Emory Eye Center and Emory Vision, Emory University, Atlanta, Georgia, USA., Methods: This retrospective analysis of LASIK, performed from June to December 2007, analyzed sphere, cylinder, and spherical equivalent (SE) refractions generated from 3 methods (manifest refraction, aberrometer autorefraction [CustomVue WaveScan], corneal analyzer autorefraction [Nidek ARK-10000 OPD]), actual programmed treatment, and absolute deviation from ideal treatment (deviation) for each technique., Results: In the wavefront-guided group (63 eyes, 33 patients), manifest refraction and aberrometer autorefraction generated similar deviation for sphere and SE; both were significantly better than corneal analyzer autorefraction (P= .02 and P= .03, respectively). Aberrometer autorefraction generated less cylinder deviation than the other methods (both P= .003). In the wavefront-optimized group (61 eyes, 36 patients), manifest refraction generated less deviation for sphere and SE than aberrometer autorefraction or corneal analyzer autorefraction (sphere: P= .005 and P= .009, respectively; SE: P= .005 and P= .002, respectively). Manifest refraction and aberrometer autorefraction cylinder generated similar deviation, while aberrometer autorefraction was less than corneal analyzer autorefraction (P= .041)., Conclusions: Overall, manifest refraction was most accurate in generating postoperative emmetropia with both laser treatments; however, aberrometer autorefraction produced the least cylinder deviation for wavefront-guided treatment. Corneal analyzer autorefraction produced the least accurate results with both lasers.

Purpose: To analyze the changes in higher-order aberrations (HOAs) that occur after wavefront-optimized photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK)., Setting: Emory Eye Center and Emory Vision, Atlanta, Georgia, USA., Methods: This retrospective analysis comprised eyes that had PRK or LASIK from June 2004 through October 2005. Postoperative outcome measures included 3-month uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), manifest refraction spherical equivalent (MRSE), changes in the root mean square (RMS) and grouped coefficient HOAs (microns) measured with a corneal analyzer, and subjective assessment of visual aberrations., Results: One hundred consecutive eyes of 54 patients had PRK, and 100 contemporaneous consecutive eyes of 71 patients had LASIK. The PRK and LASIK populations were similar in general demographics, preoperative HOAs, and postoperative UCVA and BSCVA. The mean MRSE was slightly hyperopic after PRK (mean +0.11 diopters [D]) and slightly myopic after LASIK (mean -0.19 D) (P< .0001). There were no statistically significant changes in RMS or grouped coefficient HOA values after PRK or LASIK, nor were there significant differences in postoperative RMS or grouped coefficient HOA values between PRK and LASIK. One percent of PRK and LASIK patients reported a subjective increase in postoperative visual aberrations; 5% reported a subjective improvement postoperatively., Conclusions: Wavefront-optimized excimer laser surgery did not induce significant HOAs after PRK or LASIK. The 2 techniques were equally efficacious and had equivalent postoperative HOA profiles.

Purpose: To determine the effect of different blades on laser in situ keratomileusis (LASIK) flap thickness created with the Amadeus I microkeratome (Ziemer Ophthalmic Systems)., Setting: Emory University Department of Ophthalmology and Emory Vision, Atlanta, Georgia, USA., Methods: This retrospective nonrandomized comparative case study from January 2005 through June 2006 compared LASIK flap thickness created with blades from 2 manufacturers: the Surepass from Surgical Instrument Systems and distributed by AMO and the ML7090 CLB distributed by Med-Logics, Inc. Sex, preoperative corneal thickness, surgical-eye sequence, flap thickness and variance, and residual stromal bed were evaluated in each group., Results: This study evaluated 424 eyes of 226 patients. Surepass blades were used in 238 eyes and ML7090 CLB blades in 186 eyes. There were no significant differences between the 2 blade groups in preoperative corneal thickness, sex, or cases with corneal thickness greater than 550 microm. Mean flap thickness and variance were significantly lower in the ML7090 CLB group than in the Surepass group (P<.0001). There were no significant differences in flap thickness in either group based on sex; however, in both groups, flap thickness was significantly lower in second eyes and in eyes with a preoperative thickness less than 550 microm (P<.001)., Conclusions: The Amadeus I microkeratome created thinner, more consistent LASIK flaps with the ML7090 CLB blade than with the Surepass blade. Preoperative corneal thickness and eye sequence affected flap thickness, while sex did not.

Purpose: To analyze the visual outcomes and method of final visual correction in eyes with corneal ectasia after laser in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK)., Setting: Emory University Department of Ophthalmology and Emory Vision, Atlanta, Georgia, USA., Methods: This retrospective review comprised 74 eyes of 45 patients with corneal ectasia after LASIK (72 eyes) or PRK (2 eyes). Outcomes included postoperative uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), best corrected visual acuity (BCVA), and refraction; method of final visual correction; and time to rigid gas-permeable (RGP) contact lens failure., Results: Corneal ectasia developed a mean of 19.2 months after surgery. Postoperatively, the mean UCVA was 20/400 and the mean BSCVA before ectasia management was 20/108. After ectasia management, the mean BCVA was 20/37 and the final BCVA was 20/40 or better in 78% of eyes. Final visual correction was achieved with RGP lenses in 77% of eyes, spectacles in 9%, collagen crosslinking in 3%, intracorneal ring segments in 1%, and penetrating keratoplasty (PKP) in 8%. Two eyes with intracorneal ring segments required segment explantation and subsequent PKP. One eye that had PKP had a graft-rejection episode; there were no graft failures. Two eyes (3%) did not require a visual device to improve visual acuity. The mean time for successful RGP lens wear was 24.8 months; 80% of cases initially managed with RGP lenses were successful with this form of treatment., Conclusions: The majority of eyes developing postoperative corneal ectasia achieved functional visual acuity with RGP lens wear and did not require further intervention. Penetrating keratoplasty can usually be postponed or avoided by alternative methods of visual rehabilitation; however, PKP, when necessary, can provide good visual outcomes.

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.

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.

Purpose: To compare the accuracy of intraocular lens (IOL) power calculations using 4 formulas: Hoffer Q, Holladay 1, Holladay 2, and SRK/T., Setting: Tertiary care center., Methods: This study was a retrospective comparative analysis. Immersion ultrasound biometry (axial length, anterior chamber depth, and lens thickness), manual keratometry, and postoperative manifest refraction were obtained in 643 eyes of consecutive patients who had routine uneventful cataract surgery with implantation of 1 of 2 IOLs using the same operative technique by the same surgeon. Biometric data were entered into each of the 4 IOL power calculation formulas, and the results were compared to the final manifest refraction. An optimized lens constant was used for each formula. Results were also stratified into groups of short, average, medium long, and very long axial length <22.0 mm, 22.0 to <24.5 mm, 24.5 to 26.0 mm, and >26.0 mm, respectively)., Results: No formula was more accurate than the others as measured by mean absolute error. The formulas were also equally accurate when eyes were stratified by axial length., Conclusion: The 4 IOL power formulas provided equivalent refractive results in the entire group of eyes and in the subsets of axial lengths tested.

Two patients developed corneal ectasia after photorefractive keratectomy (PRK). Case 1 had evidence of early keratoconus preoperatively, with manifest refractions of -4.00 +2.50 x 160 (20/20) in the right eye and -7.00 +3.00 x 180 (20/30) in the left eye; thin corneas (472 microm and 441 microm, respectively); and inferior paracentral steepening in the right eye and central steepening in the left eye on topography. Case 2 had manifest refractions of -8.50 +3.75 x 123 (20/20(-2)) in the right eye and -9.25 +4.00 x 077 (20/20(-1)) in the left eye; corneal thickness of 509 microm and 508 microm, respectively; and symmetric bow-tie patterns in both eyes on topography. Case 2 had a family history suspicious for keratoconus, with a sibling who had bilateral corneal transplantation at a young age. Both patients developed bilateral corneal ectasia after PRK.

Uneventful small-incision cataract surgery was performed in a 70-year-old man and a 62-year-old woman with implantation of a Tecnis Z9000 intraocular lens (IOL) (Pharmacia). No ocular pathology was present in the patients preoperatively. Unsolicited complaints of negative dysphotopsia were made postoperatively, and the symptoms have persisted for more than 1 year in both patients. Symptomatic negative dysphotopsia may be seen in association with the Z9000 IOL.

We report six-month results of the Summit Technology Myopic Keratomileusis Phase I multicenter study. Fifty-seven eyes of 57 patients had keratomileusis to correct high myopia. A microkeratome was used for the primary keratectomy and the excimer laser was used to ablate the stroma of the resected lenticle (cap) or the stromal bed (in situ). At six months, 31 of the 47 eyes available for follow-up (65.9%) had uncorrected visual acuity of 20/40 or better; 16 (34.0%) had uncorrected acuity of 20/25 or better. Thirty-seven eyes (78.7%) maintained the same (+/- one Snellen line) best corrected visual acuity as before surgery; seven (14.9%) lost two lines and three (6.4%) lost more than two lines. In addition to the six-month multicenter study results, we report two year results in a subset of 28 eyes (22 from the multicenter study and six fellow eyes). At six months, 17 of the 24 eyes available for follow-up (70.9%) had uncorrected visual acuity of 20/40 or better and nine (37.5%) had uncorrected acuity of 20/25 or better, including eyes that had worse than 20/80 best corrected visual acuity preoperatively. At 24 months, five of the seven eyes available for follow-up (71.4%) had uncorrected acuity of 20/25 or better. Only one patient lost two lines of best corrected vision at six months and no patient lost more than two lines; at 24 months, all patients maintained (+/- one line) best corrected vision.(ABSTRACT TRUNCATED AT 250 WORDS)