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PubMed1989

Tinted lenses and dyslexics--a controlled study. SPELD (S.A.) Tinted Lenses Study Group.

We have carried out a randomised prospective controlled trial of the effect of tinted lenses on the reading ability of 24 non-asthmatic dyslexic children aged between nine and twelve years. Reading ability was assessed using the Neale Analysis of Reading. After one school term, there was no significant difference in the change in reading age between treatment and control groups. After two school terms (approximately six months), only 11 children (44%) were still wearing the glasses. Of 381 suitable subjects for entry into the study, 208 were excluded because of a diagnosis of asthma (to avoid effects of medication on cerebral function). As a result, we may have excluded subjects who would have responded favourably to tinted lenses.

Child↗
PubMed2003

A randomized clinical trial of progressive addition lenses versus single vision lenses on the progression of myopia in children.

PURPOSE: The purpose of the Correction of Myopia Evaluation Trial (COMET) was to evaluate the effect of progressive addition lenses (PALs) compared with single vision lenses (SVLs) on the progression of juvenile-onset myopia. METHODS: COMET enrolled 469 children (ages 6-11 years) with myopia between -1.25 and -4.50 D spherical equivalent. The children were recruited at four colleges of optometry in the United States and were ethnically diverse. They were randomly assigned to receive either PALs with a +2.00 addition (n = 235) or SVLs (n = 234), the conventional spectacle treatment for myopia, and were followed for 3 years. The primary outcome measure was progression of myopia, as determined by autorefraction after cycloplegia with 2 drops of 1% tropicamide at each annual visit. The secondary outcome measure was change in axial length of the eyes, as assessed by A-scan ultrasonography. Child-based analyses (i.e., the mean of the two eyes) were used. Results were adjusted for important covariates, by using multiple linear regression. RESULTS: Of the 469 children (mean age at baseline, 9.3 +/- 1.3 years), 462 (98.5%) completed the 3-year visit. Mean (+/-SE) 3-year increases in myopia (spherical equivalent) were -1.28 +/- 0.06 D in the PAL group and -1.48 +/- 0.06 D in the SVL group. The 3-year difference in progression of 0.20 +/- 0.08 D between the two groups was statistically significant (P = 0.004). The treatment effect was observed primarily in the first year. The number of prescription changes differed significantly by treatment group only in the first year. At 6 months, 17% of the PAL group versus 30% of the SVL group needed a prescription change (P = 0.0007), and, at 1 year, 43% of the PAL group versus 59% of the SVL group required a prescription change (P = 0.002). Interaction analyses identified a significantly larger treatment effect of PALs in children with lower versus higher baseline accommodative response at near (P = 0.03) and with lower versus higher baseline myopia (P = 0.04). Mean (+/- SE) increases in the axial length of eyes of children in the PAL and SVL groups, respectively, were: 0.64 +/- 0.02 mm and 0.75 +/- 0.02 mm, with a statistically significant 3-year mean difference of 0.11 +/- 0.03 mm (P = 0.0002). Mean changes in axial length correlated with those in refractive error (r = 0.86 for PAL and 0.89 for SVL). CONCLUSIONS: Use of PALs compared with SVLs slowed the progression of myopia in COMET children by a small, statistically significant amount only during the first year. The size of the treatment effect remained similar and significant for the next 2 years. The results provide some support for the COMET rationale-that is, a role for defocus in progression of myopia. The small magnitude of the effect does not warrant a change in clinical practice.

Child↗
PubMed1983

Intraocular lenses versus extended-wear contact lenses in aphakic rehabilitation. A controlled clinical study.

A controlled clinical study with random allocation of method of rehabilitation (lens implant or contact lenses) was designed for comparative outcome assessments. Sixty-one patients were included in the study: 31 patients randomized to lens implantation and 30 patients to extended-wear contact lens rehabilitation with early post-operative fitting. Complication rates were low in both groups with slight accumulation of intraocular complications in the implant group and of external complications in the contact lens group. We found no significant differences between the groups in final visual acuity, in vision dependent practical functioning, or in patients' contentment. Two main points summarize our results and impressions from this study: At the expense of a slightly higher risk the lens implant patients get the most convenient and comfortable rehabilitation and at the expense of frequent visits for follow-up and lens cleaning the contact lens patients get the safest rehabilitation. The patient offered contact lens rehabilitation should be capable of alert cooperation, fairly mobile and living within easy access to ophthalmic service, while the patient offered lens implant does not need to fulfill these criteria.

Aged↗
PubMed1993

Complications and symptoms with disposable daily wear contact lenses and conventional soft daily wear contact lenses.

We conducted a historical cohort study of 1,954 myopic cosmetic contact lens wearers (1,258 disposable soft daily wear lens users and 696 conventional [nondisposable] soft daily wear lens users). Our aim was to estimate the rates of complications and symptoms among patients using daily wear disposable contact lenses on a regular disposal regimen and to compare these with rates for conventional soft daily wear users. Patients were selected from five contact lens practices in Denmark. Data were abstracted from the eye care practitioners' office records for the period October 1987 through December 1989. Virtually all of the disposable lens users were on a two-week disposal regimen. Overall, the prevalence of complications was significantly lower among the daily wear disposable lens users than among the conventional soft daily wear lens users. The incidence of corneal ulcers did not differ significantly between the two study groups. As compared to conventional soft daily wear lens users, disposable daily wear lens users reported symptoms less frequently at routine scheduled visits and had a lower rate of unscheduled visits for complications and symptoms.

Adult↗
PubMed2000

Vitreoretinal surgery through multifocal intraocular lenses compared with monofocal intraocular lenses in fluid-filled and air-filled rabbit eyes.

PURPOSE: To compare vitrectomy procedures and visualization of posterior segment structures through multifocal silicone intraocular lenses (IOLs) with the same procedures through monofocal silicone IOLs in rabbit eyes. DESIGN: Experimental study. PARTICIPANTS: Twelve eyes of six rabbits. METHODS: Each rabbit eye underwent phacoemulsification of the lens and posterior chamber implantation of a silicone multifocal or silicone monofocal IOL. The type of IOL (monofocal vs. multifocal) implanted in the first eye of each rabbit was randomly decided. The fellow eye then received the other IOL type. Vitrectomy procedures were performed through the IOLs by using a flat contact lens (part 1) or wide-angled contact lens (part 2) for visualization through fluid-filled (parts 1 and 2) and air-filled (part 2) eyes. MAIN OUTCOME MEASURES: Image quality, stereopsis, and contrast were subjectively graded on a scale of 0 (none) to 4 (excellent) for each eye by each surgeon. RESULTS: In part 1, image quality averaged 4 for the monofocal IOL and 3.6 for the multifocal IOL. Stereopsis averaged 4 for the monofocal IOL and 4 for the multifocal IOL. Contrast averaged 4 for the monofocal IOL and 3.9 for the multifocal IOL. Vitrectomy with retinal surface maneuvers was successfully performed in both pigmented and nonpigmented rabbit eyes through both IOL types. In part 2, image quality, stereopsis, and contrast were rated as 4 for both multifocal and monofocal silicone IOLs. Air-fluid exchange was performed without difficulty. Image quality, stereopsis, and contrast were rated as 4 for air-filled eyes. CONCLUSIONS: Visualization of posterior segment structures through multifocal silicone IOLs was sufficient for retinal surface maneuvers during vitrectomy procedures in both fluid-filled and air-filled rabbit eyes.

Air↗
PubMed1991

Implantation of Kelman-style, open-loop anterior chamber lenses during keratoplasty for aphakic and pseudophakic bullous keratopathy. A comparison with iris-sutured posterior chamber lenses.

The clinical and specular microscopic results of 40 cases (39 patients) of penetrating keratoplasty during which a Kelman-style anterior chamber intraocular lens was implanted were reviewed retrospectively. Thirty-one pseudophakic eyes received an intraocular lens exchange and nine aphakic eyes received a secondary intraocular lens. Postoperative follow-up averaged 24.5 months (range, 3 to 51 months). At 1, 2, and 3 years after keratoplasty, 39.3%, 63.2%, and 63.6% of eyes, respectively, had visual acuities of 20/40 or better. Ninety-five percent of the grafts remained clear. Causes of poor postoperative visual acuity included cystoid macular edema (32.5%), new glaucoma (22.5%), and age-related macular degeneration (10.0%). Other causes were endothelial rejection leading to graft failure, corneal ulceration, and retinal detachment. Corneal endothelial cell loss by specular microscopy was 11.5% at 1 years, 21.3% at 2 years, and 25.0% at 3 years. These results were compared with cell loss associated with iris-sutured posterior chamber lenses in penetrating keratoplasty. Visual outcomes and complication rates were similar between these two methods; however, the endothelial attrition at 1 and 2 years for the sutured posterior chamber lens was greater than that of the Kelman anterior chamber lens.

Adult↗
PubMed1993

[Asymmetric multizone lenses--a new concept in multifocal intraocular lenses].

BACKGROUND: Asymmetrical multifocal lenses (MIOLs) represent a new concept for binocular implantation of MIOLs: one asymmetrical IOL--destined for implantation in the dominant eye--is favouring distance vision by assuring that 60-70% of the light rays coming from an object will pass through the distance part of the optic. The other IOL--destined for implantation in the second eye--is favouring near vision, enabling that 60-70% of the light energy will be focused by the near zone(s) of the IOL. METHODS: Modulation transfer function (MTF), Strehl-Ratio (SR) and resolution efficiency (RE) were determined in both foci by in vitro measurement. Defocus curves were performed after clinical implantation as well as after "optical implantation" by means of an optical device developed by Reiner. RESULTS: In vitro measurements showed superior results of SR and RE in the favoured focus of the MIOL. Defocus curves after clinical and "optical" implantation yielded higher peaks for visual acuity and contrast in the favoured focus. CONCLUSION: First theoretical and clinical results do confirm the new concept of asymmetrical multifocal IOLs.

Contrast Sensitivity↗
PubMed2004

Cost effectiveness of foldable multifocal intraocular lenses compared to foldable monofocal intraocular lenses for cataract surgery.

AIM: To analyse the cost effectiveness of foldable monofocal intraocular lenses (IOLs) compared to foldable multifocal IOLs in cataract surgery alongside a prospective, multicentre randomised clinical trial (RCT). METHODS: Patients underwent cataract surgery with bilateral monofocal (n = 97) or multifocal (n = 93) IOL implantation. Cost data and patient preferences, using the visual analogue scale (VAS), the time trade-off (TTO), and the standard gamble (SG) technique were obtained preoperatively and postoperatively by structured interviews. The incremental costs (multifocal minus monofocal), mean costs per patient, and differences in preferences were computed. RESULTS: Mean costs for glasses per patient in the monofocal group were 41.67 and in the multifocal group 149.58. The difference in costs between the multifocal and monofocal group was -92.09 and was statistically significant (p = 0.008). No significant differences were found in total costs or in effectiveness between the monofocal and multifocal IOL group. CONCLUSION: The cost effectiveness of multifocal IOLs is reduced to a cost minimisation analysis, because of the inability to demonstrate significant differences in effects. The use of multifocal IOLs in cataract surgery resulted in a significant reduction in costs for patient's postoperative spectacles.

Aged↗
PubMed2006

Visual function in patients with yellow tinted intraocular lenses compared with vision in patients with non-tinted intraocular lenses.

AIM: To compare the visual function in patients with short wavelength blue light blocking yellow tinted intraocular lenses (IOLs) with that in patients with non-tinted IOLs. METHODS: 74 patients scheduled for bilateral cataract surgery underwent implantation of either yellow IOLs (HOYA YA60BB) or non-tinted IOLs (VA60BB) in both eyes. Contrast visual acuity with and without a glare source was measured under photopic (100 cd/m2) and mesopic (slightly higher luminance than typically used-5 cd/m2) conditions at 2 weeks and 3 months after surgery using the contrast sensitivity accurate tester. Visual acuity and the incidence of patients who noted cyanopsia were also examined. RESULTS: No significant differences between the yellow tinted and non-tinted IOL groups were observed in mean visual acuity or in photopic or higher luminance mesopic contrast visual acuity with and without glare source at either 2 weeks or 3 months after surgery. Furthermore, there was no significant difference in contrast visual acuity loss as a result of glare. The incidence of patients who noticed cyanopsia was significantly less in the yellow tinted IOL group than in the non-tinted IOL group at 2 weeks after surgery (p = 0.0234), but no patients reported cyanopsia at 3 months. CONCLUSION: Visual function in patients with yellow tinted IOLs is virtually the same as that in patients with non-tinted IOLs.

Aged↗
PubMed2002

[Treatment of dislocated lenses in patients with Marfan's syndrome using vitrectomy and intraocular lenses].

PURPOSE: To evaluate results of surgical complex treatment of lens dislocation in Marfan syndrome cases. MATERIAL AND METHODS: Nineteen eyes of 13 patients were operatively treated for lens dislocation. Pars plana vitrectomy was done in all eyes. Dislocated lenses were removed by lensectomy in 5 eyes and with an intracapsular method in 14 eyes. The scleral fixation technique was used for primary posterior chamber intraocular lens implantation in 18 eyes, and one eye remained aphakic. Time of observation ranged between 6 and 71 months (mean 3.5 years). RESULTS: All eyes achieved improvement in visual acuity or good preoperative visual acuity was maintained. The vision between 6/6 and 6/8 was achieved in 14 patients. There were no serious intraoperative or early postoperative complications. Retinal detachment appeared in two eyes in a long observation time and it was successfully operatively treated. The not good visual results were due to amblyopia (n = 2), complications of retinal detachment surgery (n = 2) and glaucomatous optic disc atrophy coexisting with macular degeneration (n = 1). CONCLUSIONS: Pars plana vitrectomy and primary scleral-fixated IOL implantation gives quick and good visual rehabilitation in adult patients with Marfan's syndrome. The described surgical method is complex and need a prolonged operative time, but gives very good functional results and very few complications.

Adult↗