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Purpose To evaluate the safety and efficacy of corneal collagen crosslinking (CXL) for the treatment of corneal ectasia after laser refractive surgery. Design Prospective, randomized, multicenter, controlled clinical trial. Participants One hundred seventy-nine subjects with corneal ectasia after previous refractive surgery. 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 (K), comparing treatment with control groups. 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 crosslinking treatment group, the maximum K value decreased by 0.7 diopters (D) from baseline to 1 year, whereas there was continued progression in the control group (1.3 D difference between treatment and control, P < 0.0001). In the treatment group, the maximum K value decreased by 2.0 D or more in 14 eyes (18%) and increased by 2.0 D or more in 3 eyes (4%). The CDVA improved by an average of 5.0 logarithm of the minimum angle of resolution (logMAR) letters. Twenty-three eyes (32%) gained and 3 eyes (4%) lost 10 or more logMAR letters. The UDVA improved 4.5 logMAR letters. Corneal haze was the most frequently reported crosslinking-related adverse finding. Conclusions Corneal collagen crosslinking was effective in improving the maximum K value, CDVA, and UDVA in eyes with corneal ectasia 1 year after treatment, with an excellent safety profile. CXL is the first approved procedure to diminish progression of this ectatic corneal process. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Purpose: To assess the outcomes of conductive keratoplasty (CK) for patients with complications related to LASIK or photorefractive keratectomy (PRK). Design: Retrospective, noncomparative, interventional case series. Participants: Sixteen eyes of 15 patients were treated using CK after complications of initial LASIK or PRK surgeries. Five cases are described in detail. Intervention: Rehabilitative CK was performed. Main Outcome Measures: Uncorrected visual acuity (UCVA) and best spectacle-corrected visual acuity (BSCVA), refractive error, keratometry, topography analysis, and a subjective assessment of visual quality. Results: After CK treatment, there was a mean improvement in UCVA of 2 lines; 1 eye lost >1 line of UCVA. Best-corrected visual acuity improved or remained the same in 12 of 15 eyes; no eyes lost >1 line of BSCVA. There was a mean reduction in astigmatism of 54%. Videokeratography generally demonstrated improved quality of the corneal optical surface, and patients reported a reduction in optical symptoms such as glare and halo. Conclusions: Conductive keratoplasty may give improved corneal optics and vision in patients with complications of LASIK or PRK. This application of CK offers an alternative in cases in which further flap manipulation or laser treatments are contraindicated. [Copyright &y& Elsevier]

: PurposeTo determine the incidence and risk factors for laser in situ keratomileusis (LASIK) retreatment and to present a novel retreatment technique.: DesignRetrospective noncomparative consecutive case series.: ParticipantsTwo thousand four hundred eighty-five eyes (1306 patients) underwent LASIK surgery for myopia, hyperopia, or astigmatism using either the Summit Apex Plus or the Alcon LADARVision excimer laser systems. Only retreatments for residual refractive error were included.: Main outcome measuresPrevalence and incidence of retreatments were determined. Potential risk factors for retreatment, including age, gender, and attempted correction, were assessed. Refractive error and a ratio of residual sphere to cylinder in retreated eyes were also analyzed.: ResultsOf the total cohort studied, 288 eyes of 233 patients underwent one retreatment, and 3 eyes of 3 patients required two retreatment procedures. The overall 1-year incidence of retreatment was 10.5%. The average length of time between initial treatment and enhancement was 7.3 ± 6.4 months; 85% of retreatments took place within 1 year. Two hundred eighty-five of the 288 retreatments were accomplished using a manual flap lift approach; 3 eyes required a repeat microkeratome cut. Higher initial corrections and residual astigmatism were associated with a significantly higher rate of retreatment. Patients older than 40 years were at greater risk for retreatment. There was no gender difference.: ConclusionsHigher initial corrections, astigmatism, and older age are risk factors for LASIK retreatment. Most LASIK flaps can be lifted using the manual technique described up to 3 years after initial surgery. [Copyright &y& Elsevier]

: ObjectiveTo document the 1-year safety, efficacy, and stability results of 355 eyes treated in the multicenter study of conductive keratoplasty (CK) used to correct low to moderate hyperopia.: DesignNonrandomized comparative (self-controlled) trial.: ParticipantsTwenty surgeons at 13 centers performed CK on the eyes of all patients enrolled in a multicenter, 2-year, U.S. phase III clinical trial. Treated eyes had +0.75 to +3.00 diopters (D) of hyperopia and ≤0.75 D of cylinder. Patients were 40 years of age or older.: InterventionLow-energy, high-frequency current was applied directly into the peripheral corneal stroma through a delivery tip inserted at 8 to 32 treatment spots. The number of treatment spots was increased for increasing levels of hyperopia, but the amount of radiofrequency energy remained constant. Emmetropia was intended. All eyes were treated once (there were no retreatments).: Main outcome measuresData from 355 eyes with 1 year of follow-up were analyzed for safety and stability, and data from 318 eyes were analyzed for efficacy and predictability, as well as stability and safety. All patients reported on satisfaction and quality of vision after surgery.: ResultsAt 1 year, uncorrected visual acuity was ≤20/20 in 56%, ≤20/25 in 75%, and ≤20/40 in 92% of eyes. The manifest refractive spherical equivalent refraction was within 0.50 D in 63%, within ±1.00 D in 89%, and within ±2.00 D in 99%. Seven of 355 eyes lost 2 lines of best spectacle-corrected visual acuity at 1 year, but no eye lost >2 lines. One eye of 355 had induced cylinder of >2.00 D. The cycloplegic refractive spherical equivalent changed a mean of 0.25 ± 0.50 D between months 3 and 6, 0.11 ± 0.41 D between months 6 and 9, and 0.11 ± 0.35 D between months 9 and 12. Refractive stability seemed to be attained by 6 months and remained stable through 12 months. Histology and confocal microscopy showed deep penetration of the treatment into the stroma. Endothelial cell counts were not changed by the treatment.: ConclusionsCK seems to be safe, effective, and stable for correcting low to moderate spherical hyperopia in patients 40 years old or older. Treatment penetration is deep and cylindrical in shape, and it does not damage the corneal endothelium. Uncorrected visual acuity, predictability, and stability are as good as or better than those obtained with other techniques used to correct hyperopia. [Copyright &y& Elsevier]

: ObjectiveTo evaluate the efficacy of phototherapeutic keratectomy (PTK) in reducing or resolving visually significant surface irregularities resulting from flap striae after LASIK.: DesignRetrospective, noncomparative case series.: ParticipantsTwenty-three eyes of 22 patients with flap striae after LASIK and reduced best-corrected visual acuity or visual symptoms that resolved with diagnostic contact lens fitting treated between January 2001 and April 2002 with at least 1 month of follow-up. The mean follow-up interval was 134 days (range, 30–354 days).: InterventionTransepithelial PTK.: Main outcome measuresUncorrected visual acuity (UCVA), resolution or reduction of preoperative symptoms, corneal haze, and best spectacle-corrected visual acuity (BSCVA).: ResultsMean BSCVA and UCVA improved significantly from 20/32 and 20/48 to 20/22 and 20/33 (P<0.0001 and P = 0.027), respectively, after PTK. There was a significant mean hyperopic shift of 0.88 diopters (D; P = 0.002, range, −1.38 to +3.88 D). Fourteen eyes (61%) were clinically clear, 6 eyes (23%) had trace haze, and 3 eyes (16%) had 1+ haze at the last follow-up visit. Mean spherical equivalent refractive error before LASIK was −7.23 D (range, −2.88 to −13.55 D). Twenty-two of 23 eyes had significant qualitative resolution or reduction of preoperative visual symptoms.: ConclusionsIn cases of visually significant LASIK flap striae, PTK is effective in improving best-corrected visual acuity and reducing visual symptoms. High myopia may be a risk factor for development of visually significant microstriae. Development of anterior stromal haze did not exceed 1+ density and was not correlated to either the number of laser pulses or the length of the follow-up period. [Copyright &y& Elsevier]