To analyze changes in the eye's refractive properties when a toric intraocular lens (IOL) rotates.Fundación Oftalmológica del Mediterráneo, Valencia, Spain.Experimental study.The matrix definition of astigmatism was used this theoretical study and compared with another vector representation. Two methods were compared: (1) The cylinder, C, resulting from addition 2 cylinders C(1) C(2) whose axes form an angle a, is obtained by vectors values forming 2a; (2) power matrix, F, thin astigmatic...

<title>Abstract</title> <bold>Background/Objectives:</bold> The aim of this work is to investigate how corneal oedema influences the thickness several layers and refractive index (n_cornea), therefore clarifying its effect on structure endothelial function.<bold>Subjects/Methods:</bold> A laboratory study was conducted with thirty-four porcine eyes, categorised into three groups: Control (non-oedematous), 24-h oedema, 48-h oedema. layers—epithelium (ET), Bowman’s membrane (BMT),...

PURPOSE: To evaluate the effect of pupil size on image quality a sectorial multifocal intraocular lens (IOL), Lentis Mplus (Oculentis GmbH, Berlin, Germany), and Acri.LISA IOL (Carl Zeiss Meditec, Jena, Germany). METHODS: The authors measured MTFs LS-312 366D with three different sizes diameters: 3, 4, 5 mm. MTF was calculated from cross-line spread function recorded OPAL Vector System (Image Science Ltd., Oxford, UK) by using fast Fourier-transform techniques. RESULTS: In distance focus,...

To assess visual quality and stabilization of refractive changes in corneal edema patients after cataract surgery, using acuity (VA) contrast sensitivity measurements.Sixty-one eyes were analysed, twenty-three with thirty-eight without edema. Uncorrected corrected distance VA (UDVA CDVA) determined an EDTRS chart, the function (CSF) under photopic mesopic illumination conditions a CVS-1000e clinical refraction, topography. Measurements taken preoperatively, 1-2 days, 1 3-months surgery....

To evaluate the changes in optical quality when toric intraocular lenses (IOL) are rotated or tilted and to demonstrate that IOL rotation produces an increasing effect of aberrations.Modulation transfer function (MTF) average modulation were used analyze image a IOL. The axis was 5°, 10°, 15°, 20°, 25°, 30° successive MTF measurements. tilt values 0° increments 1°, plus 15°. Pupil diameters 3 5 mm used.The decay due aberrations more sensitive than tilt. main decrement modulation,...

To determine the effect of main morphological types and grades age-related cataracts on refractive error. We measured 276 subjects with optical compensation prior to development cataract. evaluated 224 eyes nuclear cataract, 125 cortical 103 posterior subcapsular (PSC) cataract classified LOCSIII. visual acuity (VA) their spectacles best-corrected (BCVA) chart in decimal scale obtain optimal differences between compensations. A significant myopic shift was observed from low mild grade (p =...

Available applications for vision testing in mobile devices usually do not include detailed setup instructions, sacrificing rigor to obtain portability and ease of use. In particular, colorimetric characterization processes are generally obviated. We show that different differ also profile those differences limit the range which they most adequate.The color reproduction characteristics four devices, two smartphones (Samsung Galaxy S4, iPhone 4s) tablets Tab 3, iPad 4), have been evaluated...

We have assessed the spectral transmittance of different layers human cornea in ultraviolet (UV), visible, and near-infrared (IR) ranges. Seventy-four corneal sample donors were included study. Firstly, was measured using a spectrophotometer. Then, all samples fixed for histopathological analysis, which allowed us to measure thickness each layer. Finally, absorption coefficients computed by linear model reproducing total transmittance. The results show that transmission almost unity at...

(1) Purpose: To assess the main corneal response differences between normal and subclinical keratoconus (SCKC) with a Corvis® ST device. (2) Material Methods: We selected 183 eyes of patients, mean age 33 ± 9 years 16 patients SCKC similar age. measured best corrected visual acuity (BCVA) topography Pentacam HD device to select group. Biomechanical measurements were performed using carried out non-parametric analysis data SPSS software (Wilcoxon signed rank-test). (3) Results: found...

Apple devices could be suitable for vision tests, provided that the test has been correctly adapted to device, after considering spatial and colorimetric characterization of screen.The majority applications not developed by or colorimetry experts suffers from conceptual design errors may lead average users an erroneous assessment their visual capabilities. The reliability tests depends on accurate generation necessary stimuli in a particular device. Our aim was ascertain whether given color...

We simulate how subjects with losses in chromatic and achromatic contrast sensitivity perceive colored images by using the spatiochromatic corresponding pair algorithm.This is a generalized version of algorithm Capilla et al. (J Opt Soc Am (A) 2004;21:176-186) for simulating color perception deviant subjects, which incorporates simple spatial vision model, consisting linear filtering stage, band-pass filter two low-pass ones, red-green blue-yellow mechanisms. These filters, except global...

Ferran AdriA , chef principal del restaurante catalan y ahora fundacion elBulli, participo en 2007 la exposicion de arte contemporaneo Documenta 12 . Mi trabajo analiza este evento como interseccion tres elementos: el performance AdriA  cocinero, incorporacion ciencia tecnologia cocina lo que se conoce “tecno-cocina” cruce entre comida. En mi analisis, describo algunos los platos asi su relacion con campo artistico. lugar centrarme cuestion polemica sobre si un puede considerarse artista o...

Purpose: To analyze the optical quality of intraocular lenses (IOL) with an orange (PC440Y) and a yellow (SN60AT) filter, correlate these results visual patients implants. Setting: Fisabio Oftalmología Médica, Valencia, Spain. Design: Randomized prospective study. Materials Methods: The IOL was determined using modulation transfer function (MTF) spectral transmission. 87 eyes cataract (51 filter 36 filter) by best corrected acuity (BCVA) contrast sensitivity (CSF) under photopic mesopic...

&lt;p&gt;Ferran Adrià, chef principal del restaurante catalán y ahora fundación elBulli, participó en 2007 la exposición de arte contemporáneo &lt;em&gt;Documenta 12&lt;/em&gt;. Mi trabajo analiza este evento como intersección tres elementos: el performance Adrià cocinero, incorporación ciencia tecnología cocina lo que se conoce “tecno-cocina” cruce entre comida. En mi análisis, describo algunos los platos así su relación con campo artístico.&lt;/p&gt;&lt;p&gt;En lugar centrarme cuestión...

We have analyzed the ultraviolet transmittance of some commercial intraocular lenses (IOLs). The results show differences wavelength cutoff among them.The purpose this study was to measure and compare light different IOLs made out acrylic hydrophobic, hydrophilic, hydrophilic with hydrophobic surface materials from manufacturers.The spectral transmission curves eight monofocal same dioptric power +20.0 diopters were measured using a PerkinElmer Lambda 35 ultraviolet/visible spectrometer. Two...

An increase in lens thickness is often described as a linear function of age. However, contradictory opinions exist about whether the continues to after 50 years Differences slope between this younger and older people, but these findings are inconsistent with behavior an throughout life. We investigated among different functions, including variation, which would be best show relation available model portraying growth could advantageous many practical applications. The possibility differences...

This study presents a method for measuring scattering in explanted intraocular lenses (IOLs). Currently, determining IOLs is usually performed by Scheimpflug cameras and the results are expressed units used this apparatus. The we propose uses spectrophotometer makes it possible to measure total transmission of IOL using an integrating sphere; direct determined double-beam mode. difference between these two transmissions gives value percentage values light lost. In addition, obtaining...

Purpose. To evaluate the most common lens opacities in Valencia (Spain), analyzed by gender, grade, and type of cataracts. The results are compared with other studies performed at geographical latitudes on different races. Methods. A total 1951 eyes patients diagnosed cataracts, aged between 30 96 years, were evaluated accordance age, degree cataract, bilaterality symmetry this disease. Lens Opacities Classification System III was used to classify cataract graded as mild or moderate...

We aim to simulate how colored images are perceived by subjects with local achromatic and chromatic contrast sensitivity losses in the visual field (VF).The spatiochromatic corresponding pair algorithm, introduced a previous article (J Opt Soc Am (A) 2004;21:176-186), has been implemented linear model of system. Spatial information is processed separately mechanisms means multiscale model, sensors selective frequency, orientation, spatial position, whose mechanism-dependent relative weights...

To study the optical changes on hydrogel-silicone intraocular lenses (IOLs) resulting from loading them with dexamethasone. We used prototype hydrogel(pHEMA)-silicone IOLs and loaded matrices an anti-inflammatory drug (dexamethasone). The properties we analyzed experimentally were a) modulation transfer function (MTF); b) spectral transmission; c) diopter power. These determinations performed drug-loaded IOLs, that had released drug, not been drug-loaded. Loading a IOL dexamethasone results...