Purpose.: To experimentally measure the spectral transmission of human crystalline lenses belonging to adult and elderly persons, determine color total visible light such lenses. Methods.: The curve 32 was measured using a PerkinElmer 800UV/VIS spectrometer. Total chromatic coordinates these were determined from curves for solar illumination. Results.: lens that filters UV its in spectrum decreases with age; decrease is greater short wavelengths. decreases, especially after age 70 years,...

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...

PURPOSE: To analyze the image quality with a refractive and 2 hybrid refractive–diffractive multifocal intraocular lenses (IOLs) in vitro to determine IOL modulation transfer function (MTF) following EN-ISO international standard for distance near vision study IOLs' behavior different pupil sizes. SETTING: Fundación Oftalmológica del Mediterráneo, Valencia, Spain. METHODS: This evaluated 4 IOLs: AcrySof ReSTOR SN60D3 (Alcon) Tecnis ZM900 (AMO), ReZoom NXG monofocal SN60WF (Alcon). The MTF...

To study the relationship between optics quality of multifocal intraocular lenses (IOLs) and distance-corrected near, intermediate, distance visual acuity to determine degree which must change produce a significant difference in acuity.Fundación Oftalmológica del Mediterráneo, Valencia, Spain.Monocular (decimal logMAR) was measured at 4 m, 70 cm, 30 cm under photopic mesopic conditions eyes with 1 3 IOL models. Visual versus "average modulation" assessed.The pupil diameter patient age were...

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,...

In this paper, a multigrid motion compensation video coder based on the current human visual system (HVS) contrast discrimination models is proposed. A novel procedure for encoding of prediction errors has been used. This restricts maximum perceptual distortion in each transform coefficient. subjective redundancy removal includes amplitude nonlinearities and some temporal features perception. perceptually weighted control adaptive estimation algorithm also derived from model. Perceptual...

PURPOSE: To study in a standard eye model the changes modulation transfer function (MTF) of monofocal intraocular lens (IOL) when phakic IOL (pIOL) is placed anterior chamber, compare MTFs rigid Artisan pIOL and foldable Artiflex pIOL, evaluate temporal evolution MTF after mechanical stress undergoes injected. SETTING: Fundación Oftalmológica del Mediterráneo, Valencia, Spain. METHODS: The values IOLs were calculated from cross-line spread recorded with Opal Vector System. measurements taken...

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 whether the difference in optic quality between 2 types of phakic intraocular lenses (pIOLs) affects visual quality.Fundación Oftalmológica del Mediterráneo, Valencia, Spain.Before implantation a pIOL for myopia, all eyes had an examination including corrected (CDVA) and uncorrected (UDVA) distance acuity testing, corneal endothelial cell count (ECC), pressure (IOP) measurement. The postoperative outcomes, determined at least 1 year after surgery, were CDVA; UDVA; contrast...

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...

To evaluate the efficacy of a standard double intraocular lens (IOL) system (IOL-Vip) in patients with low vision and central scotoma due to macular degeneration assess predictability residual refraction magnification.Ophthalmology Department, Hospital General Universitario, Valencia, Spain.This interventional prospective noncomparative case series comprised 13 consecutive surgical procedures 10 scotoma. Follow-up was 12 months. Evaluation included difference between preoperative...

Purpose.: To evaluate visual function with a novel multichannel functional test named the ATD Multichannel Functional Test. Methods.: This multicenter study had prospective and cross-sectional design. A total of 186 eyes were included: 42 glaucoma, 14 glaucoma suspects due to optic nerve characteristics, 25 ocular hypertensives, 105 normal eyes. All patients performed standard fields (Humphrey 24-2) eight stimuli configurations: four achromatic (A), two red-green (T), blue-yellow (D). derive...

The contrast sensitivity function (CSF) of the whole visual system is determined with use coherent diffuse illumination. This provides supplementary data about effect speckle on ability to perceive spatial information contained in an image. results show that not only prevents perception finest details (highest frequencies) but also reduces visibility lower frequencies (especially where low). difference between CSF's and without quantitatively very important. And ratio two a measure retinal...

Summary The purpose of the present work was to study effect on visual performance wearing disposable soft tinted contact lenses for cosmetic purposes. Parameters such as contrast sensitivity (Vistech 6000), colour vision (Farnsworth‐Munsell 100‐Hue test), fields (static Goldmann perimetry) and subjective (what wearer feels while lenses) were studied under different illumination levels in order check possible losses these at low levels. Sixteen emmetropic subjects fitted consecutively with...