Search results for "Contrast sensitivity"

Visual function after implantation of an aspheric bifocal intraocular lens.

2009

Purpose To evaluate distance, intermediate, and near vision after bifocal aspheric AcrySof ReSTOR SN6AD1 intraocular lens (IOL) implantation. Setting Fernandez-Vega Ophthalmological Institute, Oviedo, Spain. Methods Binocular distance best corrected visual acuity (BCVA) (4.0 m), best distance-corrected near (40.0 cm) and intermediate (70.0, 60.0, 50.0 cm) acuities, and contrast sensitivity under photopic (85.0 candelas [cd]/m 2 ) and mesopic (3.0 cd/m 2 ) conditions with and without glare were measured postoperatively. A patient-satisfaction and visual phenomena questionnaire was administered. Results Six months postoperatively, the mean acuities (logMAR) were binocular BCVA, −0.064 ± 0.049…

Visual function after bilateral implantation of a new zonal refractive aspheric multifocal intraocular lens.

2011

Purpose To evaluate visual function after bilateral implantation of a zonal refractive aspheric multifocal intraocular lens (IOL). Setting Private practice surgery center, Valencia, Spain. Design Cohort study. Methods Consecutive eyes with cataract had bilateral implantation of Lentis Mplus LS-312 multifocal IOLs. Distance, intermediate, and near visual acuities; contrast sensitivity; defocus curves; and a quality-of-vision questionnaire, including presence of halos or dysphotopsia, were evaluated 6 months postoperatively. A control group of age-matched monofocal pseudophakic patients was included to compare contrast sensitivity function. Results In the multifocal group, the mean binocular …

One-Year Outcomes with New-Generation Multifocal Intraocular Lenses

2007

Purpose: To compare new-generation multifocal intraocular lenses (IOLs) with monofocal IOLs. Design: Randomized prospective clinical trial. Participants: Sixty-two consecutive patients with cataract, seen between January of 2005 and January of 2006 at the Department of Ophthalmology of Palermo University Hospital in Italy, were bilaterally implanted with monofocal (AR 40, Advanced Medical Optics [AMO], Santa Ana, CA; 15 patients), multifocal refractive (Array SA40N, AMO; 16 patients), multifocal refractive (ReZoom, AMO; 15 patients), or multifocal diffractive pupil-independent (Tecnis ZM900, AMO; 16 patients) IOLs. Intervention: Bimanual phacoemulsification. Main Outcome Measures: Primary o…

Chromatic-achromatic perimetry in four clinic cases: Glaucoma and diabetes

2015

Color perimetry has interesting clinical application for the diagnosis and detection of certain eye conditions, due to the variations that certain diseases can cause in chromatic thresholds, both in the red-green (RG) and the blue-yellow (BY) pathways.[1,2,3,4] The separate study of the visual function of both the chromatic and achromatic mechanisms could be more efficient in detecting sensitivity variations, and such variations would not be obscured by the intrusion of other mechanisms. Currently, the supply of conventional perimeters that are capable of performing a chromatic perimetry test is very limited and with reduced options regarding the possibility of choosing the physical charact…

Effect of sport-tinted contact lenses for contrast enhancement on retinal straylight measurements

2008

PURPOSE: To investigate the effect of two tinted contact lenses (CL) designed for outdoor sports activity on the psychometric determination of retinal straylight using the compensation comparison method. METHODS: Thirteen emmetropic subjects were randomly fitted with two different tinted Nike Maxsight (Bausch & Lomb, Rochester, NY, USA) CL in one eye, while the contralateral eye was fitted with a clear lens made of the same material (Optima 38, Bausch & Lomb). Three valid straylight measurements were taken on each eye before and a few minutes after lens insertion, when lens stabilization had occurred. RESULTS: The subjects' mean straylight values were 0.90 +/- 0.09 at baseline and 0.95 +/- …

Accommodation-related changes in monochromatic aberrations of the human eye as a function of age.

2008

PURPOSE. To investigate the relationship between accommodation and the optical aberrations of the whole human eye, as a function of age. METHODS. Sixty healthy subjects with spherical ametropia in the range 3 D, astigmatism less than 1 D, corrected visual acuity of 20/18 or better, and normal findings in an ophthalmic examination were enrolled. Subjects were divided into four groups, with age ranges of 19 to 29, 30 to 39, 40 to 49, and 50 to 60 years. Monochromatic optical aberrations and pupil size were measured with a Hartmann-Shack wavefront sensor under monocular viewing conditions, without pharmacological dilation or cycloplegia. Stimulus vergences were in the range of 0 to 5 D, with a…

Retinal straylight in patients with monofocal and multifocal intraocular lenses

2007

Purpose To determine the differences in retinal straylight perceived by patients with monofocal intraocular lenses (IOLs) and patients with multifocal IOLs. Setting Vissum-Instituto de Oftalmologico de Alicante, Alicante, Spain. Methods In this prospective study, contrast sensitivity and retinal straylight were measured prospectively 6 months postoperatively in 67 eyes of 40 patients with a monofocal or multifocal IOL. In the monofocal group, a ThinOptX IOL (ThinOptX, Inc.) was implanted in 12 eyes and an Acri.Smart 48 S IOL (Acri.Tec) in 20 eyes. In the multifocal IOL group, a ReZoom IOL (Advanced Medical Optics) was implanted in 13 eyes and a ReSTOR IOL (Alcon Laboratories) in 22 eyes. Re…

IOL Multifocali di II e III generazione: performance visiva e capacità di lettura

2011

Zilo gaismu bloķējošo lēcu ietekme uz kontrastjutību

2018

Bakalaura darbs ir 21 lappaspusi garš, satur 9. attēlus, 1. tabulu un 39. literatūras atsauces. Darba mērķis ir novērtēt zilo gaismu bloķējošo lēcu ietekmi uz kontrastjutību. Mērījumi tika veikti, izmantojot Pelli-Robsona testu, kurš tika rādīts iPad telefonā. Mērījumā piedalījās 55 dalībnieki. Mērījumi tika veikti ar briļļu lēcām, kurām bija zilo gaismu bloķējošais klājums, kā arī ar lēcām, kurām bija tradicionālais pretatspīdumu klājums. Kontrastjutība bija labāka ar zilo gaismu bloķējošām lēcām nekā ar lēcām, kurām bija tradicionālais pretatspīdumu klājums (p<0.001). Dalībniekiem ar sūdzībām par žilbšanu kontrastjutības uzlabojums ar zilo gaismu bloķējošām lēcām bija lielāks nekā dalībni…

Human contrast sensitivity in coherent Maxwellian view: effect of coherent noise and comparison with speckle.

1997

Lasers have been used in vision for measuring the neural contrast sensitivity function (CSF) by forming interference fringes on the retina. We distinguish among three kinds of illumination with lasers: incoherent (without noise), Maxwellian or coherent (with coherent noise), and diffuse coherent (with speckle). The three have different characteristics and different CSF's. A coherent imaging system is designed to measure the CSF with fully coherent illumination. This is the CSF of the whole visual system, although it is measured with gratings imaged on the retina. It therefore differs from the neural CSF's measured by other authors with partially coherent illumination. However, the neural CS…