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Purpose: To compare, in a masked manner, a novel cross-linked hyaluronic acid ocular bandage gel (OBG) versus standard-of-care bandage contact lens (BCL) plus artificial tears with respect to safety and effectiveness in healing epithelial defects created for photorefractive keratectomy (PRK). Methods: This was a randomized, reading center-masked, exploratory study. Forty-five patients (myopic without significant anisometropia) scheduled for bilateral PRK (9-mm epithelial defect) were randomized post-PRK to treatment with OBG 8 times daily for 3 days, followed by 4 times daily for 11 days (Group 1); OBG 4 times daily for 14 days (Group 2); or BCL and artificial tears (Control). A masked reading center used image analysis of digital slit lamp photos of the fluorescein-stained cornea to evaluate defect size during the 14-day postoperative follow-up period. Effectiveness endpoints were (1) time to complete closure of the corneal defect and (2) proportion of patients with complete healing on day 3 postoperatively, whose defect remained closed. Safety assessments included findings for adverse events and vision, Standard Patient Evaluation of Eye Dryness (SPEED™) Questionnaire, slit lamp, intraocular pressure, and fundus examinations. Results: The proportion of patients with complete healing at 3 days was 73.3%, 86.7%, and 66.7% of patients in Groups 1, 2, and Control, respectively. On day 2, the mean wound size was 6%-26% smaller in Groups 1 and 2 compared with Control. No safety concern arose. SPEED scores were not significantly different across groups. Conclusion: OBG offers a well-tolerated and effective therapy for quickly reepithelializing the cornea following trauma, disease, or surgery.

Purpose To identify the laser programming strategy that will achieve optimal refractive outcomes of LASIK with a topography-guided laser for eyes with a disparity between cylinder measured by manifest refraction and cylinder measured by topography. Setting Six surgeons at 5 clinical sites in the USA. Design Retrospective data review. Methods Preoperative, treatment, and postoperative data on 52 eyes that underwent topography-guided LASIK with the WaveLight EX500 Contoura® Vision excimer laser ablation profile in which the vectors representing the preoperative refractive cylinder and the cylinder measured by the WaveLight® Topolyzer™ VARIO Diagnostic Device (Vario cylinder) differed by >/= 0.50D and/or >/= 10 degrees of orientation were analyzed retrospectively. Data were contributed by six surgeons using the laser at 5 different clinical sites. Vector analysis of postoperative cylindrical refractive error and the actual laser programming strategy was used to calculate the cylindrical correction that would, theoretically, have completely eliminated postoperative refractive cylinder. This was compared to expected results using the preoperative manifest cylinder, the topographic cylinder, and the Phorcides Analytic Engine (Phorcides LLC, North Oaks MN; Phorcides). For analysis, subjects were stratified on the basis of the vector difference between Manifest and Topo cylinder (High, >0.75 D; and Low, ≤0.75 D). Results The poorest calculated theoretical outcomes were obtained with the manifest refraction (centroid: -0.43, 0.22; mean calculated error vector: 0.56 ± 0.42 D; p=ns). Better outcomes were obtained with the topographically measured refraction (centroid: 0.37, 0.02; mean calculated error vector: 0.47 ± 0.33 D; p=ns). The best outcomes were obtained with Phorcides (centroid: -0.15, 0.06; mean calculated error vector: 0.39 ± 0.28 D; p=ns). The mean error vector magnitude in the Phorcides Low group was significantly lower than for the Manifest and Topo Low groups (0.26 D vs 0.48 D and 0.33 D; p

Purpose To assess patient satisfaction and perceived outcomes with different methods of refractive error correction through annual surveys administered over a 3-year period. Design Prospective, longitudinal, parallel-group, multicenter survey. Participants A total of 1800 subjects, aged 18 to 60 years, who had LASIK or continued using contact lenses. Methods Twenty sites across the United States enrolled subjects who completed a study-specific baseline survey during a contact lens examination or while being evaluated as a candidate for LASIK. Links to follow-up surveys were emailed annually for 3 years. Between-group differences were assessed by analysis of variance, and associations were assessed by logistic multivariate regression. Main Outcome Measures Visual satisfaction. Results Of 1800 subjects, 694 (39%) comprised the control group who continued contact lens wear, 819 (45%) wore contacts at baseline and had LASIK, and 287 (16%) wore glasses at baseline and had LASIK. Most contact lens users had worn them successfully ≥5 years. The proportion expressing strong satisfaction with their current vision correction method decreased from 63% at baseline to 54% at year 3 in the contact lens control group, whereas 88% of former contact lens wearers and 77% of former glasses wearers were strongly satisfied with LASIK at year 3. Patients 40 years of age or younger when they had LASIK were somewhat more likely to be strongly satisfied than older patients. LASIK significantly reduced difficulties with night driving and nighttime visual disturbances among former contact lens users and former glasses users. The proportion with dry eye symptoms at 1, 2, or 3 years after LASIK was not significantly increased relative to baseline contact lens wear but was significantly increased relative to baseline glasses use, consistent with many glasses users having tried and abandoned contact lenses because of latent dry eye problems. Compared with continued contact lens wear, LASIK significantly reduced the self-reported rates of eye infections, ulcers, and abrasions each year. Conclusions Compared with contact lens wear, current LASIK technology improved ease of night driving, did not significantly increase dry eye symptoms, and resulted in higher levels of satisfaction at 1, 2, and 3 years follow-up.

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.Nine practices in the USA.Prospective unmasked study of safety and effectiveness.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.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).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.

Purpose To evaluate the safety and effectiveness of the Kamra small-aperture intracorneal inlay. Setting Centers in North America, Europe, Asia, and Australia. Design Prospective clinical trial. Methods Patients with emmetropic presbyopia had intracorneal implantation of the inlay in the nondominant eye. Results The study comprised 507 patients with emmetropic presbyopia who were aged 45 to 60 years old. The implanted eyes exhibited 3.5 diopters of defocus range above 20/40, with 363 (87.1%) of 417 patients and 391 (93.8%) of 417 patients having 20/40 or better monocular and binocular uncorrected near visual acuity (UNVA) at 36 months, respectively. Patients implanted via a femtosecond laser pocket procedure using a spot/line setting of 6 μm × 6 μm demonstrated further improved near vision, with 131 (90.3%) of 145 patients and 137 (94.5%) of 145 of patients having 20/40 or better monocular and binocular UNVA, respectively. Uncorrected distance visual acuity 20/25 or better was maintained in 135 (93.1%) of 145 of implanted eyes and 100% (145) of 145 of implanted eyes binocularly at 36 months. Less than 1.5% of eyes had a loss of 2 or more lines of corrected distance visual acuity for 3 months or more at any time after surgery. Forty-four inlays (8.7%) were removed from the full cohort over 3 years. The removal rate was significantly less in the 6 × 6 pocket group (3.0% for visual complaints) and further reduced with deeper implantation (0%). Less than 1.0% of the patients reported severe glare or halos postoperatively. Conclusion The small-aperture corneal inlay was found to be safe and effective, improving near vision both monocularly and binocularly with minimal effect on distance visual acuity.

PURPOSE: To evaluate the safety of the corneal inlay removal procedure and the reversibility of visual acuities, corneal topography, and corneal biomicroscopy changes in a series of cases. METHODS: Ten cases implanted with one of three versions of the AcuFocus Kamra Inlay (ACI 7000, 7000T, and 7000PDT; AcuFocus, Inc., Irvine, CA) were followed for a minimum of 6 months after corneal inlay removal. RESULTS: The reason for removal was related to subjective dissatisfaction with visual symptoms (8 of 10 patients) such as night glare, photophobia, starburst, blurry vision, and halos. One case of removal was related to inadvertent thin flap and the final case was related to insufficient near vision. Mean uncorrected distance visual acuity (UDVA) and uncorrected near visual acuity (UNVA) was 0 ± 0.1 logMAR (Snellen 20/20) and 0.5 ± 0.2 logMAR (Snellen 20/40), respectively, preoperatively and 0.1 ± 0.1 logMAR (Snellen 20/25) and 0.5 ± 0.1 logMAR (Snellen 20/63), respectively, 6 months after corneal inlay removal. Mean corrected distance visual acuity (CDVA) and corrected near visual acuity (CNVA) was 0 ± 0.1 logMAR (Snellen 20/20) and 0 ± 0.1 logMAR (Snellen 20/20), respectively, preoperatively and 0 ± 0.1 logMAR (Snellen 20/20) and 0.1 ± 0.1 logMAR (Snellen 20/25), respectively, 6 months after corneal inlay removal. Mean root mean square (RMS) higher-order aberration (HOA) was 0.50 ± 0.12 (range: 0.30 to 0.70) preoperatively and 0.69 ± 0.14 (range: 0.48 to 0.95) 6 months after corneal inlay removal ( P < .8). Weak positive correlation was found between Δt Implant-Removal (Δt I-R), RMS spherical, coma, and HOA at 6 months (Δt I-R vs RMS spherical was r = 0.2, r 2 = 0.5, P < .7; Δt I-R vs RMS coma was r = 0.8, r 2 = 0.6, P < .3; and Δt I-R vs HOA r = 0.8; r 2 = 0.6, P < .9). CONCLUSION: This study suggests that after removal of the corneal inlay, corneal topography and corneal aberrometry are not permanently affected. In more than 60% of patients, CNVA, CDVA, UNVA, and UDVA were similar to the preoperative value. [ J Refract Surg. 2013;29(8):550–556.]

Purpose To evaluate the safety and efficacy of corneal collagen crosslinking (CXL) for the treatment of progressive keratoconus. Design Prospective, randomized, multicenter, controlled clinical trial. Participants Patients with progressive keratoconus (n = 205). Methods The treatment group underwent standard CXL and the sham control group received riboflavin alone without removal of the epithelium. Main Outcome Measures The primary efficacy criterion was the change over 1 year of topography-derived maximum keratometry value, comparing treatment with control group. Secondary outcomes evaluated were corrected distance visual acuity (CDVA), uncorrected distance visual acuity (UDVA), manifest refraction spherical equivalent, endothelial cell count, and adverse events. Results In the CXL treatment group, the maximum keratometry value decreased by 1.6 diopters (D) from baseline to 1 year, whereas keratoconus continued to progress in the control group. In the treatment group, the maximum keratometry value decreased by 2.0 D or more in 28 eyes (31.4%) and increased by 2.0 D or more in 5 eyes (5.6%). The CDVA improved by an average of 5.7 logarithm of the minimum angle of resolution (logMAR) units. Twenty-three eyes (27.7%) gained and 5 eyes lost (6.0%) 10 logMAR or more. The UDVA improved 4.4 logMAR. Corneal haze was the most frequently reported CXL-related adverse finding. There were no significant changes in endothelial cell count 1 year after treatment. Conclusions Corneal collagen crosslinking was effective in improving the maximum keratometry value, CDVA, and UCVA in eyes with progressive keratoconus 1 year after treatment, with an excellent safety profile. Corneal collagen crosslinking affords the keratoconic patient an important new option to decrease progression of this ectatic corneal process.

PURPOSE: To analyze the impact of the three latest U.S. Food and Drug Administration (FDA)–approved lasers on patient-reported outcomes after LASIK. METHODS: In this meta-analysis of patient-reported FDA data, an aggregated total of 718 eyes undergoing LASIK using VISX iDesign (Abbott Medical Optics Manufacturing, Milpitas, CA), Alcon Contoura (Alcon Research, Ltd., Fort Worth, TX), and Nidek CATz (Nidek Co. Ltd., Gamagori, Japan) lasers were evaluated for overall changes in visual symptoms postoperatively. Statistical significance was calculated when appropriate to assess changes. A P value of less than .05 was considered statistically significant. RESULTS: At 12 months following LASIK, there was a decrease in the postoperative difficulty driving at night (29%) with respect to preoperative values. There was a significant postoperative reduction in prior moderate to severe symptoms for light sensitivity (9%), difficulty driving at night (22%), reading difficulty (8%), double vision (2%), glare (12%), and halos (6%) at 12 months following LASIK. CONCLUSIONS: Analysis of the FDA data shows that modern lasers have significantly improved patient-reported visual outcomes after LASIK. [ J Refract Surg. 2017;33(6):362–368.]

PURPOSE: To evaluate outcomes in patients with myopia up to −12.00 diopters (D), with or without astigmatism up to 6.00 D, who underwent LASIK with the WaveLight Refractive Suite (Alcon Laboratories, Inc., Fort Worth, TX). METHODS: This multicenter, prospective, single-arm study evaluated patients at baseline, on the day of surgery, and 1 day and 1, 3, and 6 months postoperatively. The primary outcome was comparison of 1-month postoperative binocular uncorrected distance visual acuity (UDVA) with preoperative binocular corrected distance visual acuity (CDVA). Noninferiority was defined as the upper bound of the 95% confidence interval less than 0.1 logMAR. Post-hoc analyses for superiority were conducted for monocular and binocular CDVA at 1, 3, and 6 months. Continuous variables were summarized using mean (95% confidence interval), median, quartiles, standard deviation, minimum and maximum, and categorical variables as counts and percentages. RESULTS: Of the 96 patients (54% female, mean age: 31 years), 5 underwent monocular and 91 binocular LASIK surgery (187 eyes). Preoperatively, mean binocular CDVA was −0.025 ± 0.126 logMAR, mean binocular UDVA was 1.148 ± 0.626 logMAR, and mean manifest spherical refraction equivalent was −3.67 ± 1.98 D. Postoperative binocular UDVA at 1 month (−0.088 ± 0.107 logMAR) was noninferior to preoperative binocular CDVA. Postoperative binocular UDVA at 1, 3 (−0.098 ± 0.107 logMAR), and 6 months (−0.105 ± 0.113 logMAR) were significantly superior to preoperative binocular CDVA ( P < .0001 each). CONCLUSIONS: The primary study objective was exceeded; postoperative UDVA was significantly superior to preoperative CDVA in patients with myopia and myopia with astigmatism who underwent LASIK with the WaveLight Refractive Suite. [ J Refract Surg. 2017;33(5):322–328.]

Purpose TO evaluate the endothelial cell density (ECD) change after laser-assisted in situ keratomileusis (LASIK) using IntraLase FS30®and the influence of anterior chamber gas bubbles (AC gas bubbles) produced during flap creation on the corneal endothelium during the excimer laser ablation. Methods Myopic LASIK was performed in 436 eyes of 252 patients at Shinagawa LASIK Center. Average age was 32.4±7.05 years. IntraLase FS30® was used for flap creation and Allgretto Wave Eye-Q® 400Hz was used for excimer laser ablation. Preoperative and 3-month postoperative ECD were measured with a noncontact specular microscope (Noncon Robo FA-3509®) and compared. The preoperative and 3-month postoperative ECD changes that developed AC gas bubbles during the flap creation (19 eyes of 18 patients) were also examined. The change of ECD was compared to the group that did not produce AC gas bubbles. Results The average ECD reduction after LASIK was −15±102 cells/mm2 for AC gas bubbles (-) group (0.51%, p>0.05) and-35±130 cells/mm2 (1.21%, p>0.05) for AC gas bubbles (+) group. There was no significant ECD change in the AC gas bubbles (-) and AC gas bubbles (+) groups, and no significant difference was observed between AC gas bubbles (-) and AC gas bubbles (+) groups. Conclusions IntraLase FS30® is a safe and effective tool for LASIK operation which does not cause damage to corneal endothelium. Anterior chamber gas bubbles produced during flap creation did not damage corneal endothelial cells and did not interfere with LASIK operations.

Purpose: To compare the effect of femtosecond thin-flap LASIK and photorefractive keratectomy (PRK) on postoperative endothelial cell density. Methods: In a prospective, randomized, contralateral, single-center clinical trial, 25 patients (mean age: 30±5 years [range: 21 to 38 years]) underwent PRK in one eye and thin-flap LASIK in the fellow eye for the correction of myopia using a wavefront-guided platform. The central corneal endothelial cell density was measured using the NIDEK Confoscan 4 preoperatively, and at 1 and 3 months postoperatively. Changes in endothelial cell density were analyzed over time between the two refractive techniques. Results: In PRK, the average preoperative endothelial cell density was 3011±329 cells/mm 2 , which decreased to 2951±327 cells/mm 2 at 1 month ( P =.5736) and 2982±365 cells/mm 2 at 3 months ( P =.6513). In thin-flap LASIK, the average preoperative endothelial cell density was 2995±325 cells/mm 2 , which decreased to 2977±358 cells/mm 2 at 1 month ( P =.5756) and 2931±369 cells/mm 2 at 3 months ( P =.4106). No statistically significant difference was found between the two groups at 1 ( P =.7404) or 3 ( P =.3208) months postoperatively. Conclusions: No statistically significant change was noted in endothelial cell density following either PRK or thin-flap LASIK for the treatment of myopia. Furthermore, no statistically significant difference was found between the two groups out to 3 months postoperatively, indicating that thin-flap LASIK is as safe as PRK with regards to endothelial health. [ J Refract Surg . 2009;25:1098–1102.]

The present study, which was designed as a prospective, double-masked, randomized, controlled, single-site study, was conducted to compare the effects of 3 approved ophthalmic nonsteroidal anti-inflammatory drugs-nepafenac ophthalmic suspension 0.1% (Nevanac; Alcon Laboratories, Inc., Fort Worth, Tex), ketorolac tromethamine ophthalmic solution 0.4% (Acular LS; Allergan, Irvine, Calif), and bromfenac 0.09% (Xibromtrade mark; ISTA Pharmaceuticals, Irvine, Calif)-on corneal reepithelialization and postoperative pain control in patients undergoing photorefractive keratectomy. In addition to nonsteroidal anti-inflammatory drugs, each patient received an antibiotic-moxifloxacin hydrochloride ophthalmic solution 0.5% (nepafenac group) or gatifloxacin ophthalmic solution 0.3% (ketorolac and bromfenac groups). All treatments were administered 3 times daily beginning 1 d preoperatively and continuing for 1 wk postoperatively; prednisolone acetate 1.0% was administered concurrently 4 times daily. Bandage contact lenses were replaced at each postoperative visit for corneal staining and epithelial defect grading. Self-evaluation of pain relief was recorded on postoperative days 1 and 3 with the use of a visual analog scale. A total of 29 patients (58 eyes) were enrolled and underwent bilateral custom photorefractive keratectomy. Mean time to reepithelialization was 5.50+/-1.59 d for the nepafenac 0.1% group, 5.62+/-1.23 d for the ketorolac 0.4% group, and 7.25+/-2.53 d for the bromfenac 0.09% group. A significant difference was detected between nepafenac 0.1% and bromfenac 0.09% and between ketorolac 0.4% and bromfenac 0.09% (P.05). Significant reductions in pain scores were observed with nepafenac 0.1% on day 1 (-1.13) and day 3 (-1.32), ketorolac 0.4% on day 3 (-0.88), and bromfenac 0.09% on day 3 (-0.83). No adverse events were reported. Eyes treated with nepafenac 0.1% or ketorolac 0.4% achieved complete reepithelialization significantly faster than those treated with bromfenac 0.09%. Daily contact lens removal and application of fluorescein may have delayed reepithelialization in the overall population; however, the effect would have been the same in all 3 groups. Pain relief with nepafenac 0.1% was achieved sooner than with ketorolac 0.4% or bromfenac 0.09%.

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.

Purpose: To compare the outcomes of wavefront-guided laser in situ keratomileusis (LASIK) performed using the IntraLase femtosecond laser with the outcomes using the Hansatome mechanical microkeratome. Setting: Private clinic, Overland Park, Kansas, USA. Methods: In a prospective contralateral-eye study performed under institutional review board supervision, 51 consecutive patients (102 eyes) had bilateral wavefront-guided LASIK for myopia using the Alcon LADARVision laser. One eye of each patient was randomized to have the flap created with the IntraLase femtosecond laser and the other flap using a standard compression head Hansatome microkeratome. All other treatment parameters were the same. Results: The IntraLase group had significantly better mean uncorrected visual acuity (UCVA) at all intervals from 1 day to 3 months postoperatively. The mean spheroequivalent at 3 months was more myopic with the Hansatome (-0.34 diopter [D] ± 0.28 [SD]) than with the IntraLase (-0.19 ± 0.24 D) (P

To provide 6-month results of a 1-year clinical trial evaluating conductive keratoplasty (CK) for the treatment of presbyopic symptoms in emmetropic and hyperopic eyes.A total of 143 patients with presbyopic symptoms were enrolled in this 1-year United States FDA clinical trial and treated to improve near vision in 1 eye (unilateral treatment). In addition, 33 fellow eyes were treated to improve distance vision (bilateral treatment). For near vision correction, the target refraction was up to -2.0 D in the nondominant eye, and for distance vision correction, 0.0 D. Enrolled patients had a preoperative spherical equivalent of plano to +2.00 D, no more than 0.75 D of refractive astigmatism, and were 40 years of age or older. No retreatments were performed.Of the eyes treated for near, 77% had uncorrected near vision of J3 or better at 6 months postoperatively. A total of 85% of all patients had binocular distance UCVA of 20/25 or better along with J3 or better near, a combination that represents functional acuity for a presbyope. Sixty-six percent of eyes treated for near had a manifest refractive spherical equivalent (MRSE) within +/- 0.50 D of intended at 6 months. In 89% of eyes, the MRSE changed 0.05 D or less between 3 and 6 months postoperatively. After month 1, the incidence of variables associated with safety was 1% or lower. Seventy-six percent were very satisfied or satisfied with their procedure.CK appears to be very safe and effective in producing functional visual acuity in presbyopic eyes up to 6 months following the procedure. Patient satisfaction with the procedure is similar to that of monovision LASIK.

Although less common with current surgical practices, corneal haze after PRK may still occur and require treatment. In addition, patients with corneal haze from procedures done in the past (RK or PRK before the use of mitomycin C) can present to the refractive surgeon with symptomatic corneal haze. Two-stage transepithelial PRK is a useful surgical technique for treating these patients [1, 2].

Objective To evaluate the safety and efficacy of Intrastromal Corneal Ring Segments (ICRS) for the correction of myopia. Design Nonrandomized, comparative trial. Participants Patients enrolled in the United States Food and Drug Administration phase II and phase III clinical trials of the ICRS had best spectacle-corrected visual acuity (BSCVA) of 20/20 or better, myopia of −1.00 to −3.50 diopters (D), and a cylindrical correction of 1.00 D or less as measured by manifest refraction. Intervention Surgical correction of myopia with an ICRS. Main outcome measures Efficacy was assessed by predictability of refractive outcome (deviation from predicted cycloplegic refraction spherical equivalent), stability of refractive effect, and postoperative uncorrected visual acuity. Safety was assessed by adverse events, maintenance or loss of preoperative BSCVA, and induced manifest refraction cylinder. Results Four hundred fifty-two patients were enrolled at 11 investigational sites in both studies. Of the 454 surgical attempts, 449 received an ICRS in one eye (0.25, 0.30, and 0.35 mm in 148, 151, and 150 eyes, respectively). First surgeries were attempted in 452 patients. An ICRS was successfully implanted in 447 initial eyes, and 5 surgeries were discontinued. Of the five discontinued surgeries, three patients subsequently exited from the study, and two patients went on to have the ICRS implanted in the second eye, bringing the total number of successful implants to 449 patient eyes. Month 24 postoperative follow-up was completed on 358 patients (80%). At month 24, 328 of 354 eyes (93%) were within ±1.00 D of predicted refractive outcome. Refraction changed by 1 D or less in 97% of eyes (421/435) between 3 and 6 months after implantation and in 99% (343/348) between months 18 and 24. Before surgery, 87% of eyes (390/448) saw worse than 20/40 uncorrected; 24 months after surgery, 55% of eyes (196/358) saw 20/16 or better, 76% (271/358) saw 20/20 or better, and 97% (346/358) saw 20/40 or better. Although two eyes (2/358; 0.5%) lost two or more lines of BSCVA at 24 months; visual acuity in both was 20/20 or better. Intraoperative complications included anterior corneal surface perforation (three eyes) and anterior chamber perforations (two eyes, one during an attempted exchange procedure); all healed spontaneously without suturing and without loss of BSCVA. The ICRS was repositioned in five eyes to increase correction. Postoperative complications in one eye each were infectious keratitis, shallow segment placement, and loss of two lines of BSCVA at two or more consecutive examinations (subsequently regained). Conclusions The ICRS safely, predictably, and effectively reduced or eliminated myopia of −1.00 to −3.50 D. The refractive effect was stable over time.

To evaluate the effect of a glare source on visual function in patients after photorefractive keratectomy and radial keratotomy.Thirteen patients (22 eyes) who underwent photorefractive keratectomy and 20 patients (40 eyes) who underwent radial keratotomy were evaluated in this cross-sectional study. LogMAR visual acuity and contrast sensitivity were measured. Pupils were measured with the Rosenbaum card. A halogen/tungsten glare source approximated the luminance of headlights of an oncoming car at 100 feet.In the photorefractive keratectomy and radial keratotomy groups, pupils were significantly smaller (P.01) and the pupillary clearance of the ablation zone in photorefractive keratectomy and the clear zone in radial keratotomy were significantly larger under the glare condition (P.01). In the photorefractive keratectomy group, visual acuity and contrast sensitivity under the glare condition were significantly higher than in the no-glare condition (P = .02). In the radial keratotomy group, contrast sensitivity under the glare condition was significantly higher than under the no-glare condition (P = .001 to .003).After photorefractive keratectomy or radial keratotomy, the traditional glare source constricted the pupil and partially masked the optical aberrations, which resulted in an improvement in visual function. A "pupil-sparing" aberration test is needed for evaluation of visual function after refractive surgery.

Purpose To determine the outcome of patients who received phototherapeutic keratectomy (PTK) for recurrent erosion syndrome due to anterior basement membrane dystrophy (ABMD). Design A retrospective, noncomparative case series. Participants Forty-eight eyes of 43 consecutive patients who underwent PTK for recurrent erosions occurring in ABMD at the Hunkeler Eye Center from 1991 to April 1995. All patients had previously failed at least one method of medical or surgical treatment for recurrent erosions and had slit-lamp findings of ABMD on initial evaluation. Intervention The eyes each underwent manual superficial keratectomy and PTK with the Summit Omnimed excimer laser. Main outcome measures Data were analyzed by a retrospective chart review for 1, 3, 6, and 12 months for the 36 eyes with at least 12 months of follow-up data available. They were analyzed for preoperative and postoperative visual acuity, change in spherical equivalent, recurrence rate, and patient satisfaction. Results The preoperative mean visual acuity was not statistically significantly different at 1 month after PTK. Statistically significant improvement in mean visual acuity was present at 3, 6, and 12 months. Recurrence of symptoms of recurrent erosion was present in 5 (13.8%) of 36 eyes during the 12-month follow-up period, which was managed with repeat PTK over the area of the cornea initially treated with PTK; 1 of 5 required a third PTK treatment. All recurrences presented within 6 months of PTK or repeat PTK. The mean dioptric change in spherical equivalent was not statistically significant. Patient satisfaction levels after PTK for recurrent erosions in ABMD were assessed in 21 (58%) of 36 patients on a scale of 0 to 5 (5 = most satisfied); the mean response was 4.14 of 5. Conclusions Phototherapeutic keratectomy is an effective treatment for recurrent erosions occurring in the setting of ABMD, is well tolerated, and may improve visual acuity. The rate of recurrence of erosions in ABMD treated with PTK is low during a 12-month follow-up period.

Purpose: To evaluate the relationship between contrast sensitivity, surgical treatment zone, and clearance (ablation or clear zone — pupil diameter), photorefractive keraectomy (PRK) and radial keratotomy (RK). Setting: Saint Louis University Eye Institute St. Louis, Missouri, and Hunkeler EyeCenter, Kansas City, Missouri, USA. Methods: Thirteen patients had PRK and 20, RK. Contrast sensitivity was measured with the Stereo Optical F.A.C.T. (F.A.C.T.) and VectorVision CSV 1000 (V.V) charts Pupils were measured with the Rosenbaum card. Results: In the PRK group, W contrast sensitivity at 6 and 12 cycles per degree(cpd) correlated withthe ablation zone ( r 2 = 0 18 and 0.22, respectively) while visual acuity and F.A.CT. contrast sensitivity did not correlate. In the RK group both W and F.A.C.T. contrast sensitivity contrast sensitivity at 6 cpd correlated with clearance ( r 2 = 0.29 and 0.12, respectively). Pupils were larger with the W test than with the F.A.C.T. chart because ambient chart luminance was less in the former Conclusion: Contrast sensitivity is likely a more sensitive indicator of visual function than acuity in refractive surgery. The W system unmasks aberrations, from the transition zone of ablated and unablated. cornea in PRK ; Larger samples are needed to determine the critical ablation clearance of the pupil to avoid loss of visual function.

Objective This report presents the results of a randomized clinical trial of photorefractive keratectomy (PRK) and laser-assisted in situ keratomileusis (LASIK). Design A randomized, prospective, multicenter clinical trial. Participants A total of 220 eyes of 220 patients entered the study cohort: 105 randomized to PRK and 115 to LASIK. The mean preoperative manifest refraction spherical equivalent was −9.23 diopters (D) in the PRK group and −9.30 D in the LASIK group. Intervention All patients received a one-pass, multizone excimer laser ablation as part of either a PRK or LASIK procedure using the Summit Apex excimer laser. Attempted corrections ranged from 6.00 to 15.00 D. Main outcome measures Data on uncorrected and spectacle-corrected visual acuity, predictability, and stability of refraction, corneal haze, and flap complications were analyzed. Patients were observed for up to 6 months. Results One day after surgery, 0 (0.0%) and 3 (4.5%) eyes in the PRK group saw 20/20 and 20/40 or better uncorrected, respectively, while 7 (10%) and 48 (68.6%) eyes in the LASIK group saw 20/20 and 20/40 or better, respectively. At 6 months after PRK, 13 (19.1%) and 45 (66.2%) eyes saw 20/20 and 20/40 or better, respectively, while after LASIK, 16 (26.2%) and 34 (55.7%) eyes saw 20/20 and 20/40 or better, respectively (odds ratio = 0.56 for likelihood of uncorrected visual acuity Conclusions Although improvement in uncorrected visual acuity is more rapid in LASIK than in PRK, efficacy outcomes in the longer term generally are similar between the two procedures. There is a greater tendency toward undercorrection in LASIK eyes using the specific laser and nomogram in this study, but the scatter in achieved versus attempted correction is similar, suggesting little difference in the accuracy of the two procedures. A suggestion of decreased propensity for loss of spectacle-corrected visual acuity in LASIK eyes requires further investigation.

Objective: The purpose of the study is to define qualitative patterns of corneal topography after excimer laser photorefractive keratectomy (PRK) using a 6-mm beam diameter, investigate changes in patterns over time, and identify associations of topography patterns with clinical outcomes. Design: Multicenter, prospective cohort study. Participants: Ninety-eight eyes of 90 patients with myopia who had undergone PRK using the Summit Technology, Inc., excimer laser with a 6-mm beam diameter. Intervention: Computer-assisted videokeratography data were analyzed for eyes having undergone PRK. Topography patterns at 3, 6, and 12 months after surgery were classified and associations with clinical outcomes assessed. Main Outcomes Measured: Topography patterns after PRK were determined at 3, 6, and 12 months after surgery. Associations with preoperative characteristics of age and attempted correction, and postoperative outcomes of uncorrected and spectacle-corrected visual acuity, predictability, astigmatism, corneal haze, glare, halo, and patient satisfaction were analyzed. Results: At 1 year, 21.4% of corneas showed a homogeneous topography, 27.6% showed a toric-with-axis configuration, 10.2% showed a toric-against-axis configuration, 7.1% showed an irregularly irregular topography, 24.5% showed a keyhole/semicircular pattern, and 9.2% showed focal topographic variants. From 3 to 6 months, 40.1 % of maps changed; from 6 to 12 months, 53.1 % of maps changed, generally to optically smoother, regular patterns. Older age and higher attempted correction were associated with the development of more irregular patterns. The irregular groups showed worse predictability than did the regular groups and a tendency for slight overcorrection. The average reported glare/halo of 1.33 (scale = 0 to 5) in this study was less than in a previous study of the 4.5- to 5-mm treatment zone. However, of six patients expressing dissatisfaction with the results of surgery, three ranked their glare or halo at the maximum level. Conclusions: Topography patterns using a 6-mm beam diameter are identifiable, improve with time, and may affect clinical outcomes after photorefractive keratectomy (PRK). The keyhole/semicircular pattern is more prevalent with a 6 mm treatment zone than with smaller treatment zones. Although optical side effects of glare and halo appear to be reduced with the 6-mm treatment, a small number of patients still report substantial glare or halo after the procedure.

Objective: The purpose of the study was to evaluate the safety and efficacy of the intrastromal corneal ring segments (ICRS) for the correction of myopia. Design: A 2-year phase II clinical trial of ICRS was initiated in May 1995. The investigational plan specifies that 150 patients with sighted eyes, requiring myopic corrections from −1.00 to −6.00 diopters (D), will each receive ICRS in 1 eye. The patient population will be divided into approximately five patients per ICRS thickness (0.25, 0.30, 0.35, 0.40, and 0.45 mm) per site. Six investigational sites are participating in the trial. Participants: Fifty-nine men and 43 women requiring myopic corrections were enrolled at four U.S. investigational sites. These 102 patients each received the ICRS product in 1 eye. Intervention: Correction of myopia. Main Outcome Measures: Efficacy of ICRS was assessed with respect to the trial endpoints of predictability of refractive effect, uncorrected visual acuity (UCVA), stability of UCVA, maintenance of best spectacle-corrected visual acuity and stability of refractive effect. Results: As shown by the available month-3 data (99 patients; all device thicknesses), 95 (96%) of 99 patients had a UCVA of 20/40 or better. Ninety-eight (99%) of 99 patients were within 2 lines of their preoperative best spectacle-corrected visual acuity. The average change (with standard error) in cycloplegic refraction (spherical equivalent) achieved by ICRS thickness was −1.27 ± 0.09 D (0.25 mm), −2.13 ± 0.16 D (0.30 mm), −2.56 ± 15 D (0.35 mm), −3.77 ± 0.37 D (0.40 mm) and −4.16 ± 0.24 D (0.45 mm). Seventy-seven percent (76/99) of the patients were within ±1.00 D of their intended correction. When the ICRS was removed in two cases, both patients returned to within 0.75 D of their preoperative manifest refraction. Conclusions: The ICRS appears to be a viable and effective alternative for the treatment of myopia. Additionally, as indicated by the explant data, the ICRS's refractive effect may be reversible upon removal of the device.

PURPOSE: To assess the corneal topographic and refractive results and feasibility of placing Intacs in eyes with a history of previous laser in situ keratomileusis (LASIK) surgery. METHODS: This was a prospective study on 25 eyes with residual myopia between -0.75 and -3.00 D. Residual myopia in these patients was secondary to regression or planned undercorrection due to preoperative thin corneas. RESULTS: Main outcome measures included uncorrected visual acuity, preservation of best spectacle-corrected visual acuity, refractive predictability, corneal topographic changes, and evaluation of surgical complications. CONCLUSIONS: Initial Intacs procedures after previous LASIK were performed uneventfully. In addition to correcting residual myopia, these procedures may improve night vision symptoms in some patients. These cases may improve our understanding of the ideal corneal shape. [J Refract Surg 2000;1 6(suppl):S236-S238]

Purpose: To identify preoperative and intraoperative characteristics associated with outcomes of photorefractive keratectomy (PRK). Methods: In the phase III multicenter clinical trials of the Summit Technology excimer laser for corrections of 1.5 to 6.0 diopters (D) of myopia, three principal outcomes of PRK on 612 patients were examined: (1) uncorrected visual acuity of 20/40 or better, (2) predictability of refractive outcome within 1.0 D of attempted correction, and (3) stability of refractive result between 12 and 24 months. Multiple logistic regression was used to test for independent associations of multiple preoperative and intraoperative characteristics with each of these outcomes. Results: Older age was independently associated with lesser likelihood of achieving 20/40 or better uncorrected visual acuity (odds ratio=1.08 per incremental year of age, 95% confidence interval [Cl] = 1.04–1.12) and with decreased predictability, specifically with overcorrection (odds ratio=1.09, 95% Cl=1.06–1.12), but age was not associated with stability of refraction. Greater attempted correction was associated independently with a decreased likelihood of 20/40 or better uncorrected visual acuity (odds ratio=2.78 for corrections of 3.5–5.5 D, 95% Cl=1.18–6.75; odds ratio=4.19 for corrections of ≥5.5 D, 95% Cl=1.66–10.58), with decreased predictability (odds ratio=1.72 for corrections of 3.5–5.5 D, 95% Cl=1.05–2.85; odds ratio=2.95 for corrections of ≥5.5 D, 95% Cl=1.65–5.26), and with a reduced likelihood of stability of refraction (odds ratio=3.46 for corrections of ≥5.0 D, 95% Cl=1.32–9.11). No intraoperative characteristics were associated with any of the outcomes assessed. Conclusions: Using this specific excimer laser system with an optical zone of 4.5 or 5.0 mm, patient age and attempted correction are important preoperative characteristics associated with postoperative uncorrected visual acuity and predictability of PRK. Stability of refraction is strongly associated with attempted correction. Such information may help guide patient selection, determine timing of fellow eye treatment, and suggest changes in the laser treatment algorithm for individual patients. Although these findings may be representative of PRK in general, similar analyses should be performed before modifying patient treatments using either a 6.0-mm treatment zone or other laser systems.

Purpose The 193-nm argon fluoride excimer laser can remove corneal scars and smooth corneal irregularities, obviating corneal transplantation. We conducted a prospective multicenter trial of excimer laser phototherapeutic keratectomy for corneal vision loss as a basis for Food and Drug Administration premarket approval. Methods We treated 232 eyes of 211 patients with corneal vision loss. All had corneal pathology in the anterior 100 μm of the stroma. Mean postoperative follow-up was 10 ± 8 months. The primary outcome variable was change in best spectacle-corrected visual acuity. Results At postoperative month 12, best spectacle- corrected visual acuity improved in 46 (45%) of 103 eyes and worsened in nine (9%) of 103 eyes by 2 or more Snellen lines. Best spectacle- corrected visual acuity improved by a mean of 1.6 ± 2.8 Snellen lines (95% confidence interval, 1.1 to 2.1 lines). Every postoperative visit confirmed statistically significant improvement of mean best spectacle-corrected acuity. At month 12, treated eyes had a mean hyperopic shift in refraction of 0.87 diopter and a mean reduction in astigmatism of 0.36 diopter. Treatment appeared most effective in eyes with hereditary corneal dystrophies, Salzmann's nodular degeneration, and corneal scars, and least effective in eyes with calcific band keratopathy. Complications included recurrence of underlying pathology, corneal graft rejection, and bacterial keratitis. Conclusions Argon fluoride excimer laser phototherapeutic keratectomy is effective, with relatively few complications, for treating vision loss from corneal opacification or irregularity. Efficacy, however, varies widely depending upon individual eyes and underlying diagnoses.

• Purpose: We studied the occurrence of late scarring after photorefractive keratectomy and its response to topical corticosteroids and debridement during the course of follow-up of 950 eyes that had photorefractive keratectomy with excimer laser. • Methods: Five eyes of four patients developed localized corneal scars, decreased visual acuity, and increased myopia after five to 33 months of good visual acuity, with trace haze. In two eyes, scars were removed by debridement alone. In these two eyes, recurrent scars were treated by debridement, followed by aggressive treatment with topical corticosteroids. Two other eyes were treated with topical corticosteroids alone. The fifth eye, which developed a scar after debridement to correct a subjective visual distortion after photorefractive keratectomy, was treated with debridement followed by aggressive topical corticosteroids. • Results: Treatment with topical corticosteroids alone in two eyes improved uncorrected visual acuity slightly and decreased myopia, although the scars remained unchanged. Debridement without aggressive topical corticosteroid use resulted in rapid return of the scars and a decrease in visual acuity. Subsequent debridement after aggressive topical corticosteroid treatment resulted in resolution of scars and no recurrence after discontinuation of corticosteroids in one case. In another case, the scar recurred eight months after discontinuation of topical corticosteroids. In Case 4, the scar has not recurred as the topical corticosteroid dosage has been reduced. • Conclusions: Patients who undergo photorefractive keratectomy should be counseled concerning the risk of late scarring, reexamined frequently after photorefractive keratectomy, and treated with topical corticosteroids after corneal trauma. Long-term treatment with topical corticosteroids may be required to prevent the recurrence of scars after debridement.

Purpose: To assess the influence of corneal surface microirregularities on objective and subjective visual performance after photorefractive keratectomy (PRK). Setting: Multicenter clinical trial. Methods: The alpha version of the Potential Corneal Acuity (PCA) computer program, currently under development, was used to qualitatively and quantitatively analyze the corneal surface of 176 eyes of 176 patients 1 year after PRK. Color maps of corneal surface irregularities were reviewed and quantitative values (PCA) predicting best spectacle-corrected visual acuity (BSCVA) as limited by the cornea were evaluated for associations with qualitative topography patterns, optical zone decentration, and clinical outcomes of BSCVA, uncorrected visual acuity (UCVA), subjective patient satisfaction, and a subjective glare/halo index. Results: Qualitatively, corneas after PRK were generally characterized by a ring of optical irregularity at the juncture of the ablation zone and untreated cornea. Standard corneal topography maps graded as irregular after PRK had a significantly higher PCA value than those graded as regular. There was a trend toward higher PCA values with greater optical zone decentration that was not statistically significant. Actual BSCVA was identical to that which the PCA value predicted in 32% of patients and was within one Snellen line in 71 %, within two lines in 89%, and within three lines in 94%. The correlation between the PCA and the glare/halo index and with subjective patient satisfaction was statistically significant. The relationship between PCA and UCVA was not significant. Conclusions: A ring of optical microirregularity of the corneal surface can appear at the juncture of the treated and untreated cornea after PRK, indicating that the optical zone edge might affect objective and subjective postoperative visual outcomes. Further understanding of corneal surface topography and refinement of the PCA program should help explain visual outcome after PRK.

BACKGROUND: Variation in healing response has been noted after excimer laser photorefractive keratectomy (PRK). METHODS: A retrospective analysis of 116 eyes that underwent PRK for myopia was performed. Standard surgical protocol and postoperative corticosteroid treatment were followed for all eyes. Scattergrams of achieved correction versus attempted correction at 6 months after surgery were analyzed. Subepithelial corneal haze was compared with refractive outcome. RESULTS: Three healing responses were observed. Normal responders (84.5%) showed a hyperopic overcorrection at 1 month with a gradual regression toward plano and good refractive outcome. Inadequate responders (11.2%) showed a pronounced early hyperopic overcorrection (greater than 1.50 diopters [D]) with minimal regression at 6 months. Aggressive responders (4.3%) displayed an early overcorrection with rapid regression toward myopia. Clear to trace subepithelial corneal haze was present at 6 months in 96% of normal and inadequate responders. Aggressive responders had more pronounced subepithelial haze at 6 months. CONCLUSION: Variation in the amount of subepithelial healing response occurs after excimer laser PRK. Abnormal healing responses may be detected early in the postoperative period by correlation of refractive error with the amount of subepithelial haze. [J Refract Surg. 1995;11:341-347.]

PURPOSE: To investigate whether dilute brimonidine (0.025%) reduces patient discomfort, subconjunctival hemorrhage, and injection after LASIK without a significant increase in the rate of flap complications or surgical enhancements. METHODS: This randomized, double-blind, prospective study enrolled 180 patients (360 eyes) in a contralateral eye comparison of topical dilute brimonidine, naphazoline/pheniramine, or Systane Ultra (Alcon Laboratories, Inc., Fort Worth, TX) administered shortly before LASIK for any indication. Patients were evaluated for subconjunctival hemorrhage, injection, and flap dislocation 1 hour and 1 day postoperatively. Patient questionnaires measuring patient comfort and ocular symptoms were administered at these same follow-up visits. Patients were examined for 3 months to determine similar outcomes for standard indices of safety, predictability, efficacy, and enhancement rates. RESULTS: Scores of patient discomfort, subconjunctival hemorrhage, and injection were significantly lower in eyes treated with dilute brimonidine at the 1 hour and 1 day postoperative examinations. Refloats for mild-flap edge wrinkling were required in 3 brimonidine eyes (2.5%), 1 naphazoline/pheniramine eye (0.8%), and no control eyes, but this difference did not reach statistical significance ( P = .18). There was no significant difference between eyes at 3 months in terms of visual acuity, refractive error, corrected distance visual acuity, or rate of enhancement. CONCLUSIONS: Use of dilute brimonidine before LASIK reduces subconjunctival hemorrhage and injection and improves patient comfort after surgery. Flap edge wrinkling requiring refloat may still be a complication with dilute brimonidine. [ J Refract Surg . 2013;29(7):469–475.]

PURPOSE: To investigate the speed of visual recovery following myopic thin-flap LASIK with a femtosecond laser. METHODS: This pilot study prospectively evaluated 20 eyes from 10 patients who underwent bilateral simultaneous LASIK with the Femto LDV Crystal Line femtosecond laser (Ziemer Ophthalmic Systems AG) used to create a circular flap of 9.0-mm diameter and 110-μm thickness followed by photoablation with the Allegretto Wave Eye-Q (WaveLight AG) excimer laser. Binocular and monocular uncorrected distance visual acuity (UDVA), monocular contrast sensitivity, and a patient questionnaire were evaluated during the first hours, 1 day, and 1 month postoperatively. RESULTS: For monocular UDVA, 100% of eyes were 20/40 at 1 hour and 100% were 20/25 at 4 hours. For binocular UDVA, all patients achieved 20/32 by 30 minutes and 20/20 by 4 hours. Low frequency contrast sensitivity returned to preoperative baseline by 1 hour ( P =.73), and showed a statistically significant improvement over baseline by 4 hours ( P =.01). High frequency monocular contrast sensitivity returned to preoperative baseline by 4 hours ( P =.48), and showed a statistically significant improvement by 1 month ( P =.04). At 2 and 4 hours, 50% and 100% of patients, respectively, indicated that they would feel comfortable driving. CONCLUSIONS: Visual recovery after thin-flap femtosecond LASIK is rapid, occurring within the first few hours after surgery.

BACKGROUND: A new experimental surgical technique to correct spherical hyperopia by steepening of the central corneal curvature was performed on human cadaver eyes. METHODS: Ten eyes were used in the study. All were pretreated with glycerin to ensure a uniform corneal thickness between .55 and .65 mm on ultrasonic pachometry. A constant intraocular pressure of approximately 30 to 40 mm Hg was maintained in each eye by the injection of saline into the vitreous cavity. This was verified by pneumotonometry. A vertical blade diamond knife was set at 100% of the thinnest of four paracentral readings. Each eye underwent preoperative computed topography. One set of five eyes had 12 incisions made following a 5.75-millimeter diameter Mendez hexagonal marker that included unconnected T incisions at each junction (ie, "Hex T" pattern). The other set of five eyes had four arcuate incisions made following a 6-millimeter diameter zone marker; each incision was 60° in arc. Immediately after surgery, computed topography was repeated. RESULTS: The hexagonal keratotomy set of eyes had an average steepening of the cornea of 0.80 D with a range of -1.05 to +4.38 D. The arcuate keratotomy set had an average steepening of +2.12 D with a range of + 1.27 to +3.27 D. CONCLUSIONS: This study suggests arcuate keratotomy may be a more effective procedure in the correction of spherical hyperopia when compared with hexagonal keratotomy. The amount of corneal steepening achieved in a cadaver eye model may not be the same as when performed in vivo. (Refract Corneal Surg 1993;9:388-391.)

The centration of excimer laser photorefractive keratectomy (PRK) is critical to the procedure's success. We evaluated PRK centration in 49 patients using the EyeSys topography system. Ablation zone centration was measured from the corneal vertex and from the pupillary center using the pupil-finding software. Centration was measured more accurately from the pupillary center (0.40 mm) than from the corneal vertex (0.44 mm). Right eyes were decentered less than left eyes. There was an unpredictable correlation between amount of decentration and postoperative visual acuities. The ability to measure centration of keratorefractive procedures precisely from the pupil is an important advance in topography technology.

PURPOSE: To compare differences in visual outcomes and induced spherical aberration after conventional and wavefront-optimized LASIK for the treatment of hyperopia. METHODS: In a prospective, randomized, single-center clinical trial, 51 consecutive eyes underwent LASIK for the treatment of hyperopia. Eyes were divided between groups treated with conventional LASIK with the Alcon LADAR4000 excimer laser (n=25) and wavefront-optimized LASIK with the WaveLight ALLEGRETTO excimer laser (n=26). Refractive and visual outcomes, induced spherical aberrations, and contrast sensitivity were analyzed. RESULTS: On postoperative day 1, 20% of eyes treated with a conventional profile had uncorrected visual acuity (UCVA) of 20/20 or better compared to 65% of eyes receiving wavefront-optimized treatment ( P =.0011). By 6 months, UCVA was 20/20 or better in 72% and 84% of the conventional and wavefront-optimized treatment groups, respectively ( P =.3254). At 6 months, the manifest refraction spherical equivalent was −0.21±0.47 diopters (D) and 0.16±0.27 D ( P =.6469) whereas the cylinder was −0.41±0.47 D and −0.17±0.27 D ( P =.0332) for the conventional and wavefront-optimized treatment groups, respectively. Induced spherical aberration was −0.54±0.32 µm and −0.42±0.21 µm for the conventional and wavefront-optimized treatment groups, respectively ( P =.1195). The respective change in mesopic and photopic area under the log contrast sensitivity function was −0.05±0.29 and −0.05±0.23 for the conventional treatment group and 0.08±0.39 and 0.08±0.41 for the wavefront-optimized treatment group ( P =.1970). CONCLUSIONS: Wavefront-optimized (ALLEGRETTO) and conventional (LADAR4000) ablation predictably and safely correct low to moderate hyperopia. Wavefront-optimized ablation showed superior results with regards to rapid visual recovery and residual cylinder. Although not statistically significant, a trend towards less induced negative spherical aberrations and improved mesopic and photopic contrast sensitivity was noted with wavefront-optimized treatment. [ J Refract Surg . 2010;26:356–363.]

PURPOSETo investigate the association between ocular dominance and refraction. METHODSA retrospective study of the cycloplegic refraction of 2453 consecutive patients with a mean age of 46±12 years (range: 18 to 79 years) was performed. One thousand one hundred fifty-seven (47%) patients were men and 1296 (53%) were women. Patients who had previous eye surgery, ocular disease, or >2 lines of best spectacle-corrected visual acuity (BSCVA) difference between eyes were excluded. Motor ocular dominance was determined using the hole-in-the-card test. RESULTSThe right and left eyes were dominant in 67% (1650) and 33% (803) of patients, respectively. Males had a higher right eye dominance (70%) than females (65%) (P=.0168) with a mean cycloplegic spherical equivalent refracton (SE) of –2.12 diopters (D) and –2.38 D, respectively. This higher rate of right eye dominance in males was seen at all levels of SE refractive error. Mean BSCVA was 20/19 in both right and left eyes (P>.05) with a mean SE of –2.25±3.63 D and –2.26±3.66 D in the right and left eyes, respectively. Neither mean SE difference nor BSCVA difference between eyes was found to correlate with motor eye dominance. CONCLUSIONSGender appears to be a factor when testing ocular dominance but not SE refractive error. The hole-in-the-card dominance test is a method that is easy to perform for both patients and clinicians. [J Refract Surg. 2008;24:685-689.] ABOUT THE AUTHORS From Durrie Vision, Overland Park, Kan. The authors have no financial interest in the materials presented herein. Correspondence: Ilker Eser, MD, Canakkale Onsekiz Mart University, School of Medicine, Dept of Ophthalmology, Terzioglu Yerleskesi, 17100, Canakkale Turkey. Tel: 90 532 452 9200; Fax: 90 286 218 0393; E-mail: ilkereser@yahoo.com Received: March 30, 2007 Accepted: May 25, 2007 Posted online: December 28, 2007

Purpose To determine the differences in the visual results, pain response, biomechanical effect, quality of vision, and higher-order aberrations, among other parameters, in eyes undergoing either photorefractive keratectomy (PRK) or thin-flap LASIK/sub-Bowman keratomileusis (SBK; intended flap thickness of ±100 μm and 8.5-mm diameter) at 1, 3, and 6 months after surgery. Design A contralateral eye pilot study. Participants Fifty patients (100 eyes) were enrolled at 2 sites. Methods The mean preoperative spherical refraction was –3.66 diopters (D) and the mean cylinder was –0.66 D for all eyes. Eyes in the PRK group underwent 8.5-mm ethanol-assisted PRK, whereas in eyes in the SBK group, an 8.5-mm, (intended) 100-μm flap was created with a 60-kHz IntraLase femtosecond laser (Advanced Medical Optics, Santa Ana, CA). All eyes underwent a customized laser ablation using an Alcon LADARVision 4000 CustomCornea excimer laser (Alcon Laboratories, Fort Worth, TX). Main Outcome Measures Preoperative and postoperative tests included best spectacle-corrected visual acuity, uncorrected visual acuity (UCVA), corneal topography, wavefront aberrometry, retinal image quality, and contrast sensitivity. Patients completed subjective questionnaires at each visit. Results One- and 3-month UCVA results showed a statistically significant difference: SBK, 88% 20/20 or better vs. 48% 20/20 or better for PRK. At 6 months, UCVA was 94% 20/20 or better for PRK and 92% for SBK. At 1 and 3 months, the SBK group had lower higher-order aberrations (coma and spherical aberration; P ≤0.05); at 1, 3, and 6 months, there was no statistically significant difference in spherical aberration and vertical and horizontal coma between the 2 groups. Conclusions At the 1-month follow-up, the thin-flap/SBK group demonstrated clinically and statistically significant better visual acuity than the PRK group. By 3 months, the vision in the 2 groups had begun to equalize, although the SBK eyes continued to have better vision. At 6 months, there were no statistical differences between the 2 groups. Financial Disclosure(s) Proprietary or commercial disclosure may be found after the references.

Two NSAIDs—nepafenac 0.1% and ketorolac tromethamine 0.4%—were compared in terms of their effects on corneal reepithelialization and pain after photorefractive keratectomy (PRK) in a randomized, double-masked, contralateral eye, multicenter study. A total of 40 healthy adult patients who were undergoing sequential bilateral PRK received nepafenac 0.1% and ketorolac 0.4% in contralateral eyes, 1 drop 3 times daily for 3 d after bandage contact lens insertion. Patients were assessed on postoperative days 1, 3, 4, 5, and 7. At each visit, patients provided a general rating of pain. Each patient also assessed the sensation of each eyedrop following instillation (after-drop pain, irritation, burning/stinging, and overall comfort). Starting on day 3, epithelial defect size was assessed. Mean epithelial defect size was similar between treatments at each postoperative visit (P > .05). The average time-to-healing was 4.18 d for nepafenac 0.1 % and 4.00 d for ketorolac 0.4% (P=.3134). No statistical difference was observed between nepafenac 0.1% and ketorolac 0.4% in mean postoperative pain scores (P > .05). On day 3, the nepafenac 0.1% group had significantly lower mean sensation scores than did the ketorolac 0.4% group for after-drop pain (P=.0090), irritation (P=.0007), and burning/ stinging (P=.0003). Mean overall comfort score was also significantly better for nepafenac 0.1% on day 3 (7.43 vs 6.41; P < .0001). Nepafenac 0.1% and ketorolac 0.4% provide postoperative pain relief after PRK surgery without associated adverse effects on corneal epithelial healing. Nepafenac 0.1 % treatment may offer greater comfort upon instillation in patients who have undergone PRK.

PURPOSE: Anterior segment optical coherence tomography (OCT) was used to analyze thin flaps created with the IntraLase femtosecond laser (IntraLase Corp). METHODS: Twenty-five eyes of 25 patients had flaps created with the 60 kHz IntraLase femtosecond laser prior to excimer laser ablation. The desired flap thickness was 110 µm with a diameter of 8.5 mm for all eyes. At 1 month postoperatively, all eyes were evaluated with the Visante anterior segment OCT (Carl Zeiss Meditec). Four thickness measurements were obtained across the length of the flaps at the meridians of 45°, 90°, 135°, and 180°. Thus, 16 thickness measurements were analyzed for each flap. RESULTS: Flaps were uniform (planar) with a mean thickness of 112 ?5 µm (range: 87 to 118 µm). Average standard deviation within the individual flaps was 4 µm (range: 1 to 8 ???). CONCLUSIONS: The IntraLase femtosecond laser creates thin, uniform (planar) flaps with high predictability and reproducibility. [J Refract Surg. 2007;23:555558.1

PURPOSE: To present our experience performing wavefront-guided ablations for the treatment of residual refractive error following previous refractive surgery. METHODS: Four different cases are presented ? 1) prima iy wavefront-guided LASIK; 2) wavefront-guided lift-flap LASIK retreatment; 3) wavefront-guided photorefractive keratectomy (PRK) retreatment; and 4) wavefront-guided PRK over radial keratotomy retreatment. All procedures were performed with the Alcon CustomCornea laser platform. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), manifest refraction, and wavefront analysis (6.5-mm pupil) were performed preoperatively and 3 months after CustomCornea retreatment. The Alcon LADARWave device was used for wavefront measurements. RESULTS: Total lower order and higher order aberrations were decreased following wavefront-guided retreatment, resulting in improved quality of vision. The maximum target offset (+0.75 diopters) can be used to prevent an overcorrection of defocus (myopia) when treating a significant amount of spherical aberration. CONCLUSIONS: Wavefront-guided ablation was an effective treatment for residual lower and higher order aberrations following previous refractive surgery. Custom ablation treatment algorithms need to be developed specifically for retreatment procedures. [J Refract Surg. 2005;21:S804-S807.]

PURPOSE: To compare the measured difference and degree of cyclotorsion in eyes undergoing customized laser ablation between the time of wavefront measurement and laser refractive surgery. METHODS: The degree of cyclotorsion was measured in 1019 consecutive eyes of 732 patients who underwent wavefront-guided corneal ablation for the treatment of myopia with or without astigmatism with the Alcon LADARVision excimer laser. Prior to obtaining the wavefront measurement, the horizontal axis of each eye was marked. Cyclotorsional alignment was measured on the supine patient prior to beginning the laser. RESULTS: The predominant trend was for excyclotorsion. The total range of torsion in degrees was 0.5? to 17.5? (mean: 4.05?2.9?). Cyclotorsion >2? occurred in 68% of all eyes. In the right eyes, 83% excyclotorted, 14% incyclotorted, and 3% displayed no torsion. In the left eyes, 62% excyclotorted, 34% incyclotorted, and 4% exhibited no torsion. In a subset of 112 patients undergoing simultaneous bilateral surgery, 46% displayed bilateral excyclotorsion and 1.7% displayed bilateral incyclotorsion. CONCLUSIONS: In this study, the majority of eyes had a low to moderate amount of cyclotorsion observed with the change of orientation from seated to supine position. Excyclotorsion was the predominant pattern. Proper registration prior to wavefront-guided corneal ablation is essential for proper correction of astigmatism and higher order aberrations to achieve optimal visual outcomes. [J Refract Surg. 2005;21:S772-S774.]

The purpose of these two studies was to compare the safety and tolerability of moxifloxacin 0.5% ophthalmic solution and gatifloxacin 0.3% ophthalmic solution for use with laser-assisted in situ keratomileusis (LASIK) and laser-assisted subepithelial keratomileusis (LASEK) patients. Treatment with the two antibiotic regimens was randomly assigned to fellow eyes of each patient. The LASIK study showed no difference between the two therapies in terms of visual acuity, pupil size, SPK, edema, haze, day- and nighttime glare, halos, clarity of day or night vision, and dry eye symptoms up to 1 week after surgery. Patients reported no preference between the two antibiotics on the basis of ease of use, irritation, redness, itching, gritty, sandy or scratchy feeling, speed of recovery, overall vision, or overall comfort up to 7 days after LASIK surgery. Corneal healing after LASEK surgery was equivalent for the antibiotic regimens containing moxifloxacin 0.5% ophthalmic solution and gatifloxacin 0.3% ophthalmic solution. When comparing safety and tolerability, these findings suggest an equivalent role for these fluoroquinolone antibiotics in surgical prophylaxis.

A 48-year-old man had symptoms of monocular diplopia following photorefractive keratectomy (PRK) for residual myopia after radial keratotomy. The cornea was characterized by a ring of subepithelial haze. A new type of corneal topography analysis that depicts areas of focal optical micro irregularity was used to diagnose the etiology of the optical symptoms. [Ophthalmic Surg Lasers 1996;27:315-317.]

PURPOSE: To compare the early visual results of custom laser in situ keratomileusis (LASIK) outcomes for two different excimer laser systems.METHODS: This is a preliminary report of an ongoing prospective study that evaluated 30 patients (60 eyes) who were randomized to one of two custom LASIK treatment groups: 15 patients (30 eyes) with the Alcon CustomCornea laser system (Alcon Laboratories Ine, Fort Worth, Tex) and 15 patients (30 eyes) with the Bausch & Lomb Zyoptix laser system (Bausch & Lomb, Rochester, NY). These matched patients were required to qualify for treatment with both custom laser systems. All flaps were created with the IntraLase femtosecond laser (IntraLase Corp, Irvine, Calif) using a superior hinge. Early outcome measures are uncorrected visual acuity (UCVA) at 1 day, 1 week, and 1 month postoperative; manifest refractions at 1month follow-up; and a comparison of 1 -month postoperative UCVA to preoperative best spectaclecorrected visual acuity (BSCVA). Wavefront, topography, contrast sensitivity, and subjective questionnaires were also performed and will be reported after 3-month follow-up.RESULTS: At 1 month, the percentage of eyes with UCVA of 20/20 and 20/40 were similar with 93% and 100%, respectively, for CustomCornea eyes and 90% and 97%, respectively, for Zyoptix eyes. A difference between the two groups is in the percentage of eyes with UCVA of 20/16, 20/12.5, and 20/10 with 80%, 47%, and 13%, respectively, for CustomCornea and 70%, 10%, and 0%, respectively, for Zyoptix. The mean residual spherical equivalent refraction was +0.01 ? 0.34 diopters (D) for CustomCornea and -0.04 ? 0.38 D for Zyoptix. The two groups are similar at ?1.00 D of intended correction, with CustomCornea 100% and Zyoptix 97%. However, ?0.25 D the CustomCornea group was 10% more accurate at 73% versus 63% for the Zyoptix group. The efficiency ratio (postoperative UCVA compared to preoperative BSCVA) was greater for the CustomCornea group at 20/20, 20/16, 20/12.5, and 20/10 levels.CONCLUSION: Custom LASIK with CustomCornea and Zyoptix is safe and effective and produces excellent early visual outcomes. This study demonstrates that current standard metrics for reporting refractive surgery visual outcomes are not adequate for evaluating wavefront-guided laser vision correction procedures. Amending the standard reporting metrics to include visual outcomes at the 20/16, 20/12.5, and 20/10 levels; accuracy at the ?0.25 D of attempted; and postoperative UCVA compared to preoperative BSCVA will improve our ability to analyze wavefront-guided outcomes. [J Refract Surg 2004;20:S644-S648]

PURPOSE: With the advent of wavefront-guided custom abalation we not only try to reach a target of 20/20 vision, but strive for improvement in what has always been most important - the quality of this vision. METHODS AND RESULTS: Insights are presented, based on clinical experience at Durrie Vision with our first 100 commercial CustomCornea eyes. We highlight key points for preparing a clinical practice for this new technology, such as staff training, marketing, and pricing. We discuss technical aspects such as patient selection and target adjustment as they relate to the Alcon LADARWave system. CONCLUSION: In our practice we have thus far had clinical success with CustomCornea; patient acceptance has been high, and by closely monitoring our first few patients we were able to reduce the number of future enhancements. [J Refract Surg 2003;19:S687-S690]

We report the first case, to our knowledge, of phacoemulsification with lens implantation in a patient with previous photorefractive keratectomy for myopia. Intraocular lens calculations were performed using manual and automated keratometry. The surgical and postoperative course were uneventful with a good visual outcome. Standard intraocular lens calculation and surgical technique appear to be successful for cataract extraction after photorefractive keratectomy.

PURPOSE: To report two patients (two eyes) with previous photorefractive keratectomy, who subsequently underwent cataract extraction years later. DESIGN: Case reports. METHODS: Corneal topography was used to determine corneal power used in intraocular lens power calculations. RESULTS: In two eyes of two patients, intraocular lens calculations after photorefractive keratectomy were inadequate, which resulted in a hyperopic postoperative refractive error requiring implantation of a piggyback intraocular lens. CONCLUSION: Corneal topography to determine corneal power in patients with previous photorefractive keratectomy may result in unpredictable intraocular lens power calculations. The clinical history method is the standard to determine corneal power and should be considered in intraocular lens calculations before cataract surgery. We recommend supplying refractive patients with preoperative data for use in future formulas for intraocular lens selection.