Comparative Evaluation of Spectral Transmittance of Some Welding Glasses with ANSI Z87.1

Background: Welding emits harmful rays to the eyes. We evaluate and compare the UV, blue light and IR transmittance characteristics of some currently available welding safety protectors with ANSI Z87.1 criteria.Materials and Methods: Three type of welding safety protectors (three of each type) have been evaluated for spectral transmittance. One-sample T-test was performed to establish is there a statistically significant difference between the standard criteria and UV, blue and IR regions for the welding protectors (α=0.05).Results: In ultraviolet (UV) (far and near) region, two types of the tested protectors (P1, P2) transmitted lower than the maximum allowable value specified in the standard (P<0.001). In infrared (IR) spectrum only one type (P3) transmitted lower than the maximum allowable value specified in the standard (P<0.001). In blue light region, all of the tested protectors transmitted lower than the maximum allowable value specified in the standard (P<0.001).Conclusion: Although all of the tested glasses could meet some parts of the criteria, but none of them could meet the complete spectral transmittance requirements of ANSI Z87.1

How Much of Hazardous Blue Light is Transmitted By Spectacle Lenses?

This is a Letter to the Editor and does not have an abstract

Prevalence of strabismic binocular anomalies, amblyopia and anisometropia. Rehabilitation Faculty of Shahid Beheshti Medical University

Purpose: Manifest strabismus such as constant and alternative esotropia and exotropia, not only cause cosmetic problem in patients but also induce disorders such as amblyopia. These anomalies can lead to academic failure in students and reduce efficiency in other jobs. Therefore, determining the prevalence of binocular anomalies is important. The purpose of this study is to determine the prevalence of strabismic binocular anomalies, amblyopia and anisometropia in patients examined in optometry clinic of the rehabilitation faculty of Shahid Beheshti Medical University in 2008/2009. Methods: In this study, files of 600 patients were evaluated. Cycloplegic refraction was performed in infants, elementary and middle school children and other patients had noncylcoplegic refraction. Anisometropia was defined as a difference of 1.00D or more between two eyes. Amblyopia was diagnosed as a reduction of best corrected visual acuity (BCVA) to 20/30 or less in one eye or 2-line difference in the absence of pathological causes. Cover test was performed to investigate of strabismus. Results: The prevalence of strabismic binocular anomalies, amblyopia and anisometropia were respectively: anisometropia in 64 patients (10.67%), anisometropic amblyopia in 9 patients (1.5%), anisometropic amblyopia with exotropia in 1 patient (0.17%), anisometropic amblyopia with esotropia in 1 patient (0.17%), bilateral amblyopia in 5 patients (0.83%), esotropia in 2 patients (0.33%), exotropia in 1 patients (0.17%) and convergence insufficiency in 2 patients (0.33%). Discussion: The results show that the prevalence of anisometropia was higher than shown in previous studies but prevalence of convergence insufficiency, esotropia and exotropia was lower than previous studies

A Study On The Frequency Of Different Types Of Optical Low Vision Aids Prescribed For Low Vision Patients Examined In The Clinic Of Optometry, Faculty Of Rehabilitation Sciences Shahid Beheshti University Of Medical Sciences, Tehran, 1387

Background and Aim: Different diseases can be the cause of low vision. In the case of low vision, visual acuity with conventional optical devices such as glasses and contact lenses is between” 20/70 to 20/200”. To improve the visual performance in these patients, low vision aids are prescribed.The types of prescribed low vision aids vary in different diseases. The purpose of this study is to determine the type and frequency of optical aids prescribed for low vision patients examined in optometry clinic of Rehabilitation faculty of shahid Beheshti University in 1387. Materials and Methods: In this retrospective cross-sectional study, 204 low vision patients went under investigation. In the present study variables including type and rate of refractive error, visual acuity with the best correction, type of diseases and type of prescribed optical low vision aids were investigated.Results: The frequency of prescribed distance glasses in diabetic retinopathy was 97%, age related macular degeneration 86.2%, Stargarts 92%, retinitis pigmentosa 86.4% and albinism 88.2%, Also the frequency of prescribed microscope in diabetic retinopathy was 81.82% , age related macular degeneration 48.27%, Stargarts 40% , retinitis pigmentosa 35.3% , albinism 35.3% and the frequency of prescribed magnifier in diabetic retinopathy was18.18%, age related macular degeneration 24.12% , Stargarts 52%, retinitis pigmentosa18.18% and albinism 29.4%.Conclusion: In many low vision conditions, it is more suitable to prescribe distance glasses rather than telescope. In this study the distance glass with the frequency of 84.8% is seen more acceptable in comparison with the telescope with the frequency of 41.7%. Among near optical low vision aids, microscope with the frequency of 50.5% is more accepted by the patients compared to magnifier with the frequency of 26% and CCTV with the frequency of 0.50%

Do UV-blocking soft contact lenses meet ANSI Z80.20 criteria for UV transmittance?

Purpose: To compare ultraviolet (UV) ray transmission in four UV-blocking soft contact lenses with Z80.20 standards set by the American National Standards Institute (ANSI). Methods: Four soft contact lenses including Acuvue Oasys (Johnson & Johnson, Ireland), Acuvue 2 (Johnson & Johnson, Ireland), Zeiss CONTACT Day 30 (Zeiss, Germany), and Sauflon 55 UV (Sauflon, UK) were evaluated for UV transmission. One-way ANOVA testing was performed to compare mean values of UVA and UVB transmission for the contact lenses. Results: Acuvue Oasys, Acuvue 2, Zeiss CONTACT Day 30 and Sauflon 55 UV showed UV-B transmittance values of 0.24%, 1.46%, 10.37%, and 2.52%, respectively. Corresponding values for UV-A transmittance were 20.81%, 33.49%, 44.03% and 42.53%, respectively. One-way ANOVA showed a statistically significant difference among the tested contact lenses in terms of UV-B (P < 0.001) and UV-A (P < 0.001) transmission. Conclusion: Acuvue Oasys met the ANSI criteria for UV transmission and may thus be a good choice for eye and vision care specialists and contact lens wearers seeking UV protection

A Comparative Investigation of Prescriptive Ophthalmic Lens Parameters with Iranian National Standards

Background and Aim: Wearing spectacles is the most common procedure for correction of refractive error and because of its close relationship with eye; the standards of frame & lens of glasses play a very important role in preventing vision problems. The purpose of this study was to compare spherical & cylindrical power and prismatic effect of plastic ophthalmic lenses with Iranian national standards.Material & Method: In this Cross sectional-Comparative study 48 plastic ophthalmic single vision lenses were inspected & compared with relative national standards i.e.: ISIRI 8715-1:1385.Results: The spherical power factor with instruments set as step 0.01, all the cases(-1.00,-3.00,-6.00) were in tolerance with limits of the standards (±0.12 D) .The instrument was set for 0.01 step for cylindrical power, at -6.00 D 100% of lenses had no cylindrical power. At -3.00 & -1.00 D about 99% were in tolerance with the standards (±0.09 D).The effect of horizontal & vertical prism, at the power of -6.00 all lenses show prismatic effect but 99% were in tolerance with the standards (±0.85D). At the power of -3.00 & -1.00 D, prismatic effect of lenses were in tolerance with relative standards (±0.55, ±0.35), respectively. Conclusion: All single vision were collected from famous companies showed the quality of passing all factors of tests & gained Iranian national standards i.e.: ISIRI 8715-1:1385