Search results for "Myopia."
showing 10 items of 163 documents
Opportunities and threats to contact lens practice: A global survey perspective
2021
Aim: To understand the views of contact lens (CL) practitioners across the globe regarding what they perceive as opportunities and threats in CL practice. Methods: A self-administered anonymised questionnaire, constructed in English and translated in six more languages, was distributed through reputed international professional bodies and academic institutions worldwide. The questionnaire included items on demographic characteristics, type of practice, and questions designed to explore practitioners’ perspective on the future of their CL practice over the next five years. Results: A total of 2408 valid responses were analysed. Multifocal CLs for presbyopia, CLs for myopia control, use of da…
Visual Acuity in Myopes with Standard and Reversed Contrast Optotypes
2017
Abstract The aim of this study was to assess the visual acuity of myopes with standard and reversed contrast optotypes and to determine how the visual acuity of myopes is affected by optical defocus and the type of optical correction, either contact lenses or spectacles. Twenty-three myopic subjects (18 and 23 years old) with uncorrected vision had their visual acuity assessed with both standard and reversed contrast optotypes. The study also included 10 myopes with contact lens as well as habitual spectacle correction. The visual acuity for myopes with uncorrected vision was better with reversed than standard contrast optotypes. Better reversed contrast than standard contrast visual acuity…
Ārā pavadītā laika ietekme uz miopijas progresēšanu
2021
Bakalaura darbs ir uzrakstīts angļu valodā uz 25 lapaspusēm. Tas satur 13 attēlus, 5 tabulas un 16 literatūras atsauces. Darba mērķis ir novērtēt āra aktivitāšu ietekmi uz miopijas attīstības kavēšanu. Dati tika iegūti ar jautājumu anketu palīdzību. Rezultāti rāda, ka āra aktivitātes šajā pētījumā nav nozīmīgs faktors, kurš kavē miopijas veidošanos (p<0.05). Nozīmīgs miopijas veidošanās faktors ir iedzimtība.
High myopic patients with and without foveoschisis: morphological and functional characteristics.
2020
Purpose: Myopic foveoschisis (MF) is characterized by the splitting of the retinal layers in the fovea of patients with high myopia (HM). MF may progress into foveal detachment or macular hole formation with consequent loss of central vision. The aim of this study is to investigate morphological and functional changes of the macular region in myopic subjects with and without foveoschisis. Design: Observational, cross-sectional, comparative study. Methods: Forty-eight patients with HM and 24 healthy controls were evaluated by spectral domain-optical coherence tomography (SD-OCT), multifocal electroretinography (mfERG) and microperimetry (MP-1) tests to assess macular thickness, functionality…
Predictability of intraocular lens power calculation after small-incision lenticule extraction for myopia
2019
PURPOSE To evaluate and compare the predictability of intraocular lens (IOL) power calculation after small-incision lenticule extraction (SMILE) for myopia and myopic astigmatism. SETTING Department of Ophthalmology, Philipps University of Marburg, Marburg, Germany. DESIGN Retrospective comparative case series. METHODS Preoperative evaluation included optical biometry using IOLMaster 500 and corneal tomography using Pentacam HR. The corneal tomography measurements were repeated at 3 months postoperatively. The change of spherical equivalent due to SMILE was calculated by the manifest refraction at corneal plane (SMILE-Dif). A theoretical model, involving the virtual implantation of the same…
Ortokeratoloģijas pielietojums miopijas progresēšanas kontrolei skolas vecuma bērniem
2017
Bakalaura darbs ir uzrakstīts latviešu valodā uz 36 lapām. Tas satur 25 attēlus, 1 tabulu un 20 literatūras avotus. Pētījuma mērķis ir nodemonstrēt, Ortho-K lēcu lietošana var palēlināt miopijas progresēšanu skolas vecuma bērniem, kuriem ir miopija. Pētījumā piedalījās 28 bērni (vidējais vecums 10 ± 2 gadi) ar vidējo miopijas lielumu -3,15 D ± 1,43 D (astigmātisms mazāks par 1,00 D) ārstēšanas sākumā. Miopijas progresēšana tika novērota vienu gadu pirms Ortho-K lēcu lietošanas un 3 gadus, lietojot Ortho-K lēcas. Rezultāti rāda, ka vidējais miopijas progresēšanas apjoms pirms Ortho-K lēcu lietošanas bija -0,86 D ± 0,53 D gada laikā un tas nozīmīgi (p << 0,0001) samazinājās līdz -0,04 D ± 0,1…
Ocular Refraction at Birth and Its Development During the First Year of Life in a Large Cohort of Babies in a Single Center in Northern Italy
2020
The purpose of this study was to investigate refraction at birth and during the first year of life in a large cohort of babies born in a single center in Northern Italy. We also aimed to analyze refractive errors in relation to the gestational age at birth. An observational ophthalmological assessment was performed within 24 h of birth on 12,427 newborns. Refraction was examined using streak retinoscopy after the administration of tropicamide (1%). Values in the range of between +0.50 ≤ D ≤ +4.00 were defined as physiological refraction at birth. Newborns with refraction values outside of the physiological range were followed up during the first year of life. Comparative analyses were condu…
Modulation transfer function: Rigid versus foldable phakic intraocular lenses
2008
Purpose To study in a standard eye model the changes in modulation transfer function (MTF) of a monofocal intraocular lens (IOL) when a phakic IOL (pIOL) is placed in the anterior chamber, compare the MTFs of the rigid Artisan pIOL and foldable Artiflex pIOL, and evaluate the temporal evolution of the MTF of the foldable pIOL after the mechanical stress the pIOL undergoes when injected. Setting Fundacion Oftalmologica del Mediterraneo, Valencia, Spain. Methods The MTF values of the IOLs were calculated from the cross-line spread function recorded with the Opal Vector System. The measurements were taken using an eye model following the British and EN-ISO standards with 2.0 mm, 3.0 mm, 4.0 mm…
The posterior chamber phakic refractive lens (PRL): a review
2012
Implantation of phakic intraocular lenses (pIOLs) is a reversible refractive procedure, preserving the patient’s accommodative function with minimal induction of higher order aberrations compared with corneal photoablative procedures. Despite this, as an intraocular procedure, it has potential risks such as cataracts, chronic uveitis, pupil ovalization, corneal endothelial cell loss, pigmentary dispersion syndrome, pupillary block glaucoma, astigmatism, or endophthalmitis. Currently, only two models of posterior chamber pIOLs are commercially available, the implantable collammer lens (STAAR Surgical Co.) and the phakic refractive lens (PRL; Zeiss Meditec). The number of published reports on…
Implantable collamer lens and femtosecond laser for myopia: comparison using an adaptive optics visual simulator.
2014
Purpose: To compare optical and visual quality of implantable collamer lens (ICL) implantation and femtosecond laser in situ keratomileusis (F-LASIK) for myopia. Methods: The CRX1 adaptive optics visual simulator (Imagine Eyes, Orsay, France) was used to simulate the wavefront aberration pattern after the two surgical procedures for -3-diopter (D) and -6-D myopia. Visual acuity at different contrasts and contrast sensitivities at 10, 20, and 25 cycles/degree (cpd) were measured for 3-mm and 5-mm pupils. The modulation transfer function (MTF) and point spread function (PSF) were calculated for 5-mm pupils. Results: F-LASIK MTF was worse than ICL MTF, which was close to diffraction-limited MT…