ISSN:1542-2321    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose.To establish the safety and efficacy of clinical performance of a novel hyper-O2–transmitting rigid gas-permeable (RGP) lens (tisilfocon A) worn continuously for 30 days (29 nights) equivalent to a conventional control hydrogel lens (etafilcon A) worn for 7 days (6 nights).Methods.The study was a prospective, open-label, 24-center, concurrent cohort-controlled clinical trial.Outcome Measures.Outcome measures included rates of adverse events, slitlamp findings, length of wear achieved, lens-corrected visual acuity, corneal refractive changes, dryness, and lens deposits.Results.The RGP lens wear test was equivalent or superior to the hydrogel control performance in all categories. Two-thirds (66.5%) of patients wearing the RGP lens achieved continuous wear periods greater than 22 nights; and 60.4% achieved more than 28 nights of continuous use. There was a statistically significant lower rate of adverse events, considered definitely related to lens wear, for the RGP test lens versus the hydrogel control (none vs. 2.2%;P= 0.007, Fisher’s exact two-sided test).Conclusions.Continuous wear of the tisilfocon A (Menicon Z, Menicon Co., Ltd., Nagoya, Japan) RGP lens for up to 30 nights is a safe and equivalent alternative to 7-day (6-night) hydrogel wear.

ISSN:1542-2321    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose.This study was conducted to measure the corneal thickness changes associated with wearing 30-day tisilfocon A (Dk = 163) and 6-day etafilcon A (Dk = 28) contact lenses. The probable cause of the outcomes is discussed.Methods.Thirty subjects were fitted with Menicon Z rigid gas-permeable (RGP) contact lenses and a control group (n = 30) was fitted with ACUVUE hydrogel lenses, at two study sites. After a 2-week period of daily wear, subjects began prolonged wear. Measurements were performed at the dispensing visit, and then at the 2-week daily wear, the 1-week, 6-month, and 12-month extended- and continuous-wear visits.Results.Repeated measures analysis of covariance was performed on mean corneal thickness. There was a significant increase in corneal thickness in the hydrogel lens extended-wear group compared to the RGP group (P= 0.03). The mean corneal thickness in the ACUVUE group was 2.58% higher at the 2-week daily wear visit, 2.38% higher at the 1-week extended-wear visit, 2.96% higher at the 6-month, and 2.97% higher at the 1-year visit compared to the RGP continuous-wear patients.Discussion.Patients wearing high-Dk RGP contact lenses for continuous wear may have thinner corneas (within the normal thickness range) probably because of minimal hypoxia-induced corneal stromal swelling; RGP-induced reversible corneal epithelial compression; deceased epithelial sloughing; or long-term contact lens-induced keratocyte apoptosis.Patients wearing hydrogel contact lenses for extended wear may have thicker corneas because of hypoxia-induced corneal stromal swelling. Additional evidence of corneal hypoxic stress is seen in the higher prevalence of striae and epithelial microcysts in the hydrogel group and greater variability of corneal thickness measurements in the soft contact lens group in our results.

ISSN:1542-2321    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose.This evaluation was conducted as part of a protocol entitledEvaluation of the Menicon Z Rigid Gas Permeable Contact Lens for up to 30 Days Extended Wear. The purpose of the protocol was to compare corneal endothelial morphology changes after wearing rigid gas-permeable (RGP) Menicon Z contact lenses, continuously for up to 30 days, with ACUVUE (Johnson & Johnson Vision Care) hydrogel contact lenses, worn for up to 6 nights of extended wear.Methods.Sixty patients, who were adapted to RGP daily wear and soft contact lens daily wear, were recruited at two study sites. The thirty subjects who wore RGP daily wear lenses were fitted with the Menicon Z (tisilfocon A, oxygen permeablility [Dk] = 163) RGP contact lens comprised the test group. The control group subjects (n = 30 former users of daily wear soft contact lenses) were fitted with ACUVUE (etafilcon A, Dk = 28) hydrogel contact lenses. After a 2-week adaptation period of daily wear, subjects began extended wear. Endothelial imaging was performed at the two study sites in this multicenter study (University Hospitals of Cleveland/Case Western Reserve University Department of Ophthalmology [CWRU] and The Ohio State University [OSU]). The hydrogel lens group was instructed to wear their lenses for 7 days and 6 nights before discarding the lenses and to sleep with no lenses on the seventh night. The RGP group was permitted to wear the lenses for up to 30 days and 29 consecutive nights before removing the lenses for cleaning and overnight soaking.Results.CWRU had 24 patients (12 soft contact lens and 12 rigid contact lens) and OSU had 21 patients (12 soft contact lens and 9 rigid contact lens) who completed the study and were included in the analyses. Patients who were withdrawn from the study at CWRU included one RGP patient dropped out because of pregnancy; one RGP patient developed vascularized limbal keratitis and discomfort; one could not be fitted with a bitoric RGP; two soft lens patients moved from the area, and one dropped out because of dry eyes. At OSU, four patients dropped out due to discomfort (two in each lens type); one moved from the study area; one decided not to participate soon after the consent visit; one had worries of reduced vision at 6 months; one subject’s attitude changed prior to the 6 month visit; and one subject was withdrawn for reasons of poor study schedule compliance.Conclusion.The Menicon Z lens wearers in this study did not show significant endothelial cell morphology changes after 1 year of nearly continuous contact lens wear. This finding is particularly important considering the RGP wearers in this study were older by a average of 10 years (mean age approximately 40) and had worn their contact lenses an average of almost 10 years longer than the soft contact lens wearers.

ISSN:1542-2321    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose.A body of clinical and laboratory evidence suggests that tinted spectacle lenses may have an effect on visual performance. The aim of this study was to quantify the effects of spectacle lens tint on the visual performance of 25 subjects with cataracts.Methods.Cataracts were scored based on best-corrected acuity and by comparison with the Lens Opacity Classification System (LOCS III) plates. Visual performance was assessed by measuring contrast sensitivity with and without glare (Morphonome software version 4.0). The effect of gray, brown, yellow, green and purple tinting was evaluated.Results.All subjects demonstrated an increase in contrast thresholds under glare conditions regardless of lens tint. However, brown and yellow lens tints resulted in the least amount of contrast threshold increase. Gray lens tint resulted in the largest contrast threshold increase.Conclusions.Individuals with lenticular changes may benefit from brown or yellow spectacle lenses under glare conditions.

ISSN:1542-2321    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

This article presents the case of a 49-year-old man who did not have a history of wearing contact lenses and who developed a rapidly progressive course ofAcanthamoebakeratitis. The patient developed stromal keratitis that did not respond to herpes simplex virus therapies. Within 1 week after presentation, the patient progressed from mild anterior stromal haze and edema to a ring infiltrate, epithelial loss, and significant corneal edema. Corneal scrapings demonstrated cysts consistent withAcanthamoebakeratitis. The patient was admitted to the hospital and placed on intensive medical therapy. He responded to therapy, and at 5 months showed central scarring in a quiet eye. This article presents a case ofAcanthamoebakeratitis in a non-contact lens wearer, who was diagnosed clinically and histopathologically within 1 week of onset of symptoms. His case was atypical given his lack of contact lens wear or antecedent trauma and rapid progression to a ring infiltrate, usually seen as late findings.

ISSN:1542-2321    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose.To evaluate changes in corneal thickness after 2, 4, and 6 weeks of frequent-replacement contact lens wearing.Material and Methods.Twenty-eight patients were fitted with ACUVUE (Johnson & Johnson) contact lenses. Central and peripheral corneal thickness was measured before contact lens fitting and after 2, 4, and 6 weeks of wearing.Results.Analysis of variance shows that the period of contact lens wearing has no influence on central corneal thickness. After a small increase in the second week, central corneal thickness returns to the initial values in the fourth and sixth weeks of contact lens wearing. Peripheral corneal thickness was statistically related to the time of contact lens wearing (P<0.01). A statistically significant difference was observed between the baseline and peripheral corneal thickness measurements in the second, fourth, and sixth week of contact lens wearing (P<0.01).Conclusions.Frequent-replacement contact lenses (ACUVUE) cause a small amount of corneal edema, which is higher in the periphery than in the center. Central corneal swelling disappears after 6 weeks of wearing, but in the periphery it remains stable throughout the period of observation.

ISSN:1542-2321    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose.The purpose of this study is to assess the effects of commercially available contact lens wetting solutions on bacterial binding and cell exfoliation rates in human corneal epithelium.Methods.The effects of four contact lens care solutions were tested: ReNu Multi Plus (Bausch & Lomb, Rochester, NY) multipurpose solution; OPTI-FREE Express (Alcon, Ft. Worth, TX) multipurpose solution; Complete Blink-N-Clean (Allergan, Irvine, CA) lens drops; and Lens Plus (Allergan) rewetting drops.Study Design.Prospective, double-masked, randomized crossover clinical trial (N = 20 subjects).Outcome Measures.Measures of outcome included binding ofPseudomonas aeruginosa(PA) to exfoliated corneal epithelial cells, and the rate of surface cell exfoliation. Cells were collected at the baseline (pretreatment) examination and 4 days later, after subjects used the assigned solution six times daily and once again immediately before cell collection (posttreatment). Following cell collection, patients underwent 1 week of recovery, during which no drops were used, and random cross-over assignment to the next test solution.Results.Use of test solutions increased PA binding, with a range of + 11.9% to + 58.2%. Analyzed together, PA binding increased significantly (+ 29%;P= 0.02, pairedt-test); Lens Plus solution alone raised PA binding levels significantly (P= 0.022, 2-way ANOVA, Student-Newman-Keuls [SNK] test). Exfoliation rates were decreased from −7% to −52.7%. Analyzed together, cell exfoliation decreased significantly (P= 0.004; Wilcoxon signed rank test). Individual use of OPTI-FREE decreased exfoliation significantly (P= 0.019; 2-way ANOVA, SNK test).Conclusions.Topical application of common commercial contact lens care solutions increases PA binding and reduces corneal surface cell exfoliation. Similar effects have also been reported with contact lens wear. Taken together, the data suggest that the use of lens solution itself may play a role in increasing PA binding to corneal epithelial cells and, hence, might potentially contribute inadvertently to increased risk for lens-related microbial keratitis.

ISSN:1542-2321    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Objective.To compare photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) in treating spherical hyperopia using the VISX STAR S2 excimer laser.Intervention.Fifteen consecutive eyes of 15 patients underwent PRK, and 16 consecutive eyes of 16 patients underwent LASIK (follow-up: 12 months).Main Outcome Measures.Postoperative pain, uncorrected visual acuity (UCVA), deviation from intended correction, and loss of best spectacle-corrected visual acuity (BSCVA).Results.Mean preoperative spherical equivalent was + 2.18 diopter [D] for PRK and + 2.03D for LASIK. All PRK patients experienced significant postoperative pain that required systemic medication, whereas LASIK patients had minor and transient discomfort. Mean deviation from intended correction was −0.83D, + 0.01D, and + 0.18D at 1, 6, and 12 months after PRK, and + 0.22D, +0.30D, and + 0.40D at 1, 6, and 12 months after LASIK (P= 0.002 at 1 month). A higher proportion of LASIK eyes had a UCVA of 20/20 or better at all time points (P= 0.013 and 0.025 at 1 and 3 months, respectively). There was no statistically significant difference between both groups in BSCVA loss.Conclusions.LASIK and PRK are comparable in efficacy and safety. However, PRK was more painful, with an initial and temporary myopic over-correction that did not occur after LASIK. Stability was achieved between 3 and 6 months following PRK, and one month following LASIK.

ISSN:1542-2321    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose.To compare two preservative-free hydrating agents, in multidose (ABAK) bottles, in contact lens wearers experiencing symptoms of ocular dryness.Methods.The endpoint of this 4-week multicenter, randomized, double-blind, parallel-group study comparing a 2% polyvinylpyrrolidone (PVP) solution with a 0.9% NaCl solution was to assess ocular discomfort using a visual analog scale. A biomicroscopic examination and a test of tolerability on instillation were also performed, and adverse events were recorded.Results.Thirty-nine subjects were enrolled (23 PVP; 16 NaCl). The average age was 30; subjects were predominantly female, and mostly wore frequent-replacement contact lenses. They were all exposed to environmental factors such as routine use of video monitors or air conditioning. The two groups were similar at baseline (D0). Both PVP and NaCl improved the comfort of contact lens wear (P= 0.0003), with no difference between them (P= 0.25). The mean daily duration of lens wear and the daily number of instillations to relieve discomfort (4.2 ± 2.0 for PVP ABAK; 4.6 ± 1.9 for NaCl ABAK) were comparable. However, PVP use led to more favorable evolution of fluorescein-staining corneal punctuations (P= 0.028). Safety was good, with minimal adverse events considered unrelated to the products. Lens wettability was excellent, and there were no clinically relevant deposits. Most subjects also found the ABAK bottles convenient.Conclusions.Ocular hydration improves comfort in contact lens wearers. NaCl is an appropriate first-line treatment, but for subjects with fluorescein-staining punctuations, lubrication with PVP is preferable.

ISSN:1542-2321    

出版商:OVID    

年代:2003

数据来源: OVID