571 research outputs found
Is refraction with a hand-held autorefractometer useful in addition to visual acuity testing and questionnaires in preschool vision screening at 3.5 years in Japan?
The vision-screening program for 3.5-year-old children in Japan consists of 3 steps:questionnaires and home visual acuity testing, visual acuity testing by nurses and inspection by medical officers at regional Public Health Centers, and examinations by ophthalmologists. In this study, we tested refraction with a hand-held autorefractometer in addition to visual acuity testing and inspection to reveal whether or not autorefraction leads to better detection of eye problems. Autorefraction was performed in 6 consecutive sessions by a single examiner in 265 children at 3.5 years of age who all visited the same center. The children were sent to the third step of examinations by ophthalmologists based on refractive error criteria:3 diopters myopia or 1 diopter hyperopia, and/or 2 diopters astigmatism in either eye, in addition to the current criteria:1) failure in either eye for 0.5 visual acuity at the center, 2) eye-related symptoms revealed by the questionnaires, or 3) eye problems detected by medical officers. Notices to visit ophthalmologists were issued for 64 children (24%), and 37 of those (58%) made the visits, so that documents containing final diagnoses were sent back to the Public Health Office. Of the 64 children, 12 were sent to ophthalmologists based on the current criteria only, 10 based on both the current criteria and the refractive error criteria, and 42 based on the refractive error criteria only. Twelve of the 13 children visiting ophthalmologists by the current criteria had diagnoses such as amblyopia and strabismus. In contrast, 15 of 24 children visiting ophthalmologists by only the refractive error criteria had mainly diagnoses of refractive errors, with no serious problems. In conclusion, autorefraction in addition to visual acuity testing and inspection led to detection of only one additional case of an eye disease at 3.5 years, while tripling the number of children sending to the third-step examination by an ophthalmologist. Thus, from a cost-effectiveness standpoint, autorefraction is not recommended as an additional test when the current system is conducted as designed.</p
Microfabrication of Three-Dimensional Structures in Polymer and Glass by Femtosecond Pulses
We report three-dimensional laser microfabrication, which enables
microstructuring of materials on the scale of 0.2-1 micrometers. The two
different types of microfabrication demonstrated and discussed in this work are
based on holographic recording, and light-induced damage in transparent
dielectric materials. Both techniques use nonlinear optical excitation of
materials by ultrashort laser pulses (duration < 1 ps).Comment: This is a proceedings paper of bi-lateral Conf. (Republics of China &
Lithuania) on Optoelectronics and Magnetic Materials, Taipei, May 25-26,
2002.
Photorefraction with Spot Vision Screener versus Visual Acuity Testing as Community-Based Preschool Vision Screening at the Age of 3.5 Years in Japan
Nationwide in Japan, a community-based vision-screening program in 3.5-year-old children is conducted in three steps: questionnaires and home visual acuity testing as the primary screening; visual acuity testing by nurses and pediatricians’ inspection in community health centers as the secondary screening; and examinations by ophthalmologists as the tertiary screening. In this study, we introduced photorefraction with a Spot vision screener in addition to visual acuity testing to answer the clinical question of whether photorefraction could better detect eye diseases and potentially replace visual acuity testing. Photorefraction was performed on 813 consecutive 3.5-year-old children in a center. The children were sent to tertiary examinations, which were based on the Spot vision screener standard, in addition to the visual acuity testing standard: failure in either eye to pass 0.5 visual acuity in a center. A notice to visit ophthalmologists was issued for 95 children (11%), and documents with the diagnosis were sent back to the Heath Office for 76 children (80%). The rate of children with anisometropic or ametropic amblyopia or accommodative esotropia as treatment-requiring diseases was highest in cases of no pass at both standards (10/15 = 66%), and higher in cases of no pass only at the Spot vision screener standard (13/45 = 28%), compared with cases of no pass only at the visual acuity testing standard (6/33 = 18%, p = 0.0031). Photorefraction, in addition to visual acuity testing and inspection led to additional eye diseases detection at 3.5 years. Visual acuity testing at home would not be omitted in the introduction of photorefraction
CONTRIBUTION OF FORWARD AND VERTICAL IMPULSES DURING MAXIMAL 5OM SPRINTING TO THE MAXIMUM RUNNING VELOCITY IN SPRINTERS
The present study developed a 50 m-forceplate system and examined relationships between the impulse calculated from ground reaction force (GRF) from start to 50m and the maximum running velocity (Vfmax). Thirty five male sprinters performed maximal sprint on the system, using starting block. The forward and vertical components of impulses (IMPf and IMPv. respectively) were computed far each support phase by integrating the GRF. The highest correlation coefficients for both IMPf(~0.736)a nd IMPv(r=-0.729) were found at the distance of 10 m from the start. These results indlcate the ability to keep lMPv low and lMPf high seems to be important for achieving greater Vfmax, notably in the initial stage of acceleration phase
Detection of strabismus and amblyopia in 1.5- and 3-year-old children by a preschool vision-screening program in japan
All children at the age of 1.5 and 3 years in Japan undergo physical, mental, and developmental checkups including dental, eye, and hearing examinations. The vision-screening program consists of 3 steps : questionnaires and home visual acuity testing as the first step (only for 3-year-old children), visual acuity testing by nurses and inspection by medical officers at regional Health Centers as the second step, and detailed examinations by ophthalmologists as the third step. This study aims to reveal the prevalence of strabismus and amblyopia as obtained from data in the vision-screening program. The final diagnoses made by ophthalmologists and sent back to the Health Centers in Okayama City were reviewed to elucidate the prevalence of strabismus, amblyopia, refractive errors, and other diseases in 1.5- and 3-year-old children in Okayama City in 5 years from 2000 to 2004. Of approximately 6,500-6,900 total children, 83.7-86.8% at 1.5 years old and 77.8-81.9% at 3 years old were brought to the Health Centers. The rates of strabismus were 0.01-0.12% at 1.5 years old and 0.20-0.34% at 3 years old, while the rates of amblyopia were 0% at 1.5 years old and 0.13-0.18% at 3 years old. The higher rates of strabismus at 3 years old were attributed mainly to the increase of exotropia and intermittent exotropia. In conclusions, the prevalence of strabismus was different between 1.5- and 3-year-old children. The vision-screening program in Japan functions to detect strabismus and amblyopia
ACCURACY IN DETERMINING KINETIC PARAMETERS WITH FORCE PLATES EMBEDDED UNDER SOIL-FILLED BASEBALL MOUND
We developed a force measurement system embedded in a soil-filled mound for measuring ground reaction forces (GRF) acting on baseball pitchers and examined the accuracy of determining the point of force application (PFA) and kinetic parameters computed from GRF. Three 1.0 x 0.9 m2 force platforms were placed on the concrete foundation of an indoor sports facility and three bays were fixed onto the aluminum plates of the force plateorms. In each tray, clay-blocks were laid tightly and a mixture of red sand and volcanic-ash was used to make a smooth surface layer. The mean absolute error was 6.0 f 4.0 mm in determining PFA, less than 15.5 Ns (5% of the true value) in determining linear impulse. These results suggest that the present method is valid for measuring the PFA and GRF acting on the pitcher's legs for analyzing kinetics of pitching performances
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