Search results for "myopia progression"
showing 4 items of 4 documents
The effect of fractal contact lenses on peripheral refraction in myopic model eyes.
2014
Purpose: To test multizone contact lenses in model eyes: Fractal Contact Lenses (FCLs), designed to induce myopic peripheral refractive error (PRE). Methods: Zemax ray-tracing software was employed to simulate myopic and accommodation-dependent model eyes fitted with FCLs. PRE, defined in terms of mean sphere M and 90–180 astigmatism J180, was computed at different peripheral positions, ranging from 0 to 35 in steps of 5, and for different pupil diameters (PDs). Simulated visual performance and changes in the PRE were also analyzed for contact lens decentration and model eye accommodation. For comparison purposes, the same simulations were performed with another commercially available conta…
Relative Peripheral Myopia Induced by Fractal Contact Lenses
2018
[EN] Purpose: To assess the peripheral refraction induced by Fractal Contact Lenses (FCLs) in myopic eyes by means of a two-dimensional Relative Peripheral Refractive Error (RPRE) map. Materials and Methods: This study involved 26 myopic subjects ranging from -0.50 D to -7.00 D. FCLs prototypes were custom-manufactured and characterized. Corneal topographies were taken in order to assess correlations between corneal asphericity and lens decentration. Two-dimensional RPREs were measured with an open-field autorefractor at 67 points, covering the central 60 x 30 degrees of the visual field. The bidimensional RPRE vector components: M, J(0) and J(45) of the difference between the values obtain…
Virskorekcijas pielietojamība tuvredzības progresijas novērtēšanā ortokeratoloģijas pacientiem
2022
Darbs ir uzrakstīts angļu valodā uz 93 lapaspusēm. Tas satur 49 attēlus, 24 tabulas un 95 atsauces uz literatūras avotiem. Šī darba mērķis ir pārbaudīt, vai virskorekcija ir derīga metode tuvredzības progresēšanas novērtēšanai ortokeratoloģijā. Hipotēze ir atrast lielākas izmaiņas gados jaunākiem pacientiem nekā pieaugušajiem, kā tas ir norādīts literatūrā. Pētījumā iekļauti 192 Eiropeīdās rases subjekti vecumā no 6 līdz 56 gadiem (vidēji 19,61±10,30). Izmantojot retrospektīvu analīzi, no objektīva BOZR kontaktlēcas parametra tiek iegūta virskorekcija (ORX). Jaunākiem cilvēkiem ir lielākas ORX vērtības, bet pieaugušajiem nav atšķirības (p<0,05). Vidēji tuvredzība progresēja par –0,18±0,44 D…
Comparison of myopic progression in Finnish and Singaporean children
2020
Purpose To compare 3-year myopic progression between Finnish and Singaporean children. Methods Myopic progression was compared between 9-year-old (mean age 9.7 ± 0.4 years, n = 92) and 11-year-old (mean age 11.7 ± 0.4 years, n = 144) Finnish (Finnish RCT) children and Singaporean children matched by age and refraction (SCORMMatched, n = 403) and 7- to 8-year-old Singaporean children matched only by refraction (SCORM Young, n = 186). Spherical equivalent (SE) was between −0.50 and −3.00 D. Refraction with cycloplegia was controlled annually for 3 years. Information on parental myopia, mother’s education, time spent on near-work and outdoor time was gathered by parental questionnaire. Results…