Search results for "mesopic vision"
showing 10 items of 45 documents
Visual performance with simultaneous vision multifocal contact lenses.
2011
Purpose: The aim was to assess visual performance after PureVision high addition multifocal contact lens (PM) fitting through contrast sensitivity measured under different illumination levels for both distance and near. Methods: In a cross-over study, 20 presbyopic patients were randomly assigned to PM or spectacles. Near contrast sensitivity was measured with the Vistech VCTS 6500 system. Distance contrast sensitivity and distance visual acuity (VA) were measured with the Functional Vision Analyser under photopic (85 cd/m2) and mesopic (3.0 cd/m2) conditions, the latter also under two levels of induced glare: 1.0 lux and 28 lux. Near VA was measured by logMAR charts under approximately 8…
Contrast sensitivity after LASIK flap creation with a femtosecond laser and a mechanical microkeratome
2007
ABSTRACT PURPOSE: To compare the effects on contrast sensitivity of the IntraLase femtosecond laser for flap creation (IntraLASIK) and standard LASIK for myopia. METHODS: Two hundred eyes of 100 consecutive patients underwent LASIK treatment using the VISX S2 laser system. The femtosecond laser (15 kHz IntraLase) was used for flap creation in 100 eyes (50 patients) and a mechanical microkeratome (Carriazo-Barraquer) was used in 100 eyes (50 patients). Best spectacle-corrected contrast sensitivity was measured before and 6 months postoperatively in the IntraLASIK and mechanical LASIK groups. The IntraLASIK and mechanical LASIKinduced changes in contrast sensitivity were compared under photop…
Rod-cone based color vision in seals under photopic conditions
2016
Marine mammals have lost the ability to express S-cone opsin, and possess only one type of M/L-cone in addition to numerous rods. As they are cone monochromats they should be color blind. However, early behavioral experiments with fur seals and sea lions indicated discrimination ability between many shades of grey and blue or green. On the other hand, most recent training experiments with harbor seals under "mesopic" conditions demonstrated rod based color blindness (Scholtyssek et al., 2015). In our experiments we trained two harbor seals (Phoca vitulina) and two South African fur seals (Arctocephalus pusillus) with surface colors under photopic conditions. The seals had to detect a triang…
Contrast sensitivity and color perception with orange and yellow intraocular lenses
2012
To evaluate contrast sensitivity function (CSF) and color vision after implantation of either orange or yellow-tinted intraocular lenses (IOLs).Fifty-six eyes of 28 cataract patients who had bilateral implantation of orange-tinted (PC440Y Orange, Ophtec), yellow-tinted (AcrySof Natural SN60AT, Alcon), or clear (AcrySof SA60AT, Alcon) IOLs were examined. Six months postoperatively, monocular CSF under photopic and mesopic (with and without glare) conditions were measured using the Functional Visual Analyzer. Color discrimination was determined with the Farnsworth-Munsell 100-Hue test.Patients implanted with orange-tinted, yellow-tinted, or clear IOLs displayed similar CSF values, with no sta…
Influence of trifocal intraocular lenses on standard autorefraction and aberrometer-based autorefraction.
2019
To study the agreement between manifest refraction and objective refraction measured with two autorefractor models and an aberrometer in eyes implanted with a trifocal diffractive intraocular lens (IOL).IOA Madrid Innova Ocular, Madrid, Spain.Prospective comparative cohort study.An autorefractor keratometer (KR-8800), based on a Scheiner double pinhole, and a 3-dimension wavefront topography aberrometer system (OPD-Scan III), based on the scanning-slit retinoscopy principle, were used to obtain objective refraction readings. In addition, lower-order Zernike coefficients (Z) were used to calculate objective refraction. A set of 7 different results was obtained in power vector notation (spher…
Working-Age Cataract Patients: Visual Results, Reading Performance, and Quality of Life with Three Diffractive Multifocal Intraocular Lenses
2013
Purpose To compare the visual outcomes, reading performance, and quality of life (QoL) of working-age cataractous patients bilaterally implanted with 3 different diffractive multifocal intraocular lenses (MIOLs). Design Two-center, randomized, prospective, double-masked study. Participants Sixty-three consecutive patients (126 eyes) seen at Ophthalmology Section, Palermo and Florence University, Italy, randomized to receive the ReSTOR SN6AD3 (Alcon Laboratories, Inc, Irvine, CA) (20 patients, group A), ReSTOR SN6AD1 (Alcon Laboratories, Inc) (21 patients, group B), or TECNIS ZMA00 (Abbott Medical Optics, Santa Ana, CA) (22 patients, group C) MIOL. Intervention Phacoemulsification. Main Outc…
Visual and Refractive Outcomes in Hyperopic Pseudophakic Patients Implanted with the Acri.LISA 366D Multifocal Intraocular Lens
2009
Our purpose was to assess the visual quality after bilateral implantation of the Acri.LISA 366D intraocular lens (IOL; Carl Zeiss Meditec, Jena, Germany) in patients with hyperopia. We did a prospective and nonrandomized study. One hundred and seventy eyes of 85 patients had bilateral implantation of the Acri.LISA 366D IOL. The patients were divided into 2 groups: low to moderate hyperopia (IOL power, 21 to 24.5 diopters [D]) and high hyperopia (IOL power, 25 to 36 D). Monocular and binocular best spectacle-corrected visual acuity (BSCVA), best distance-corrected near visual acuity (BCNVA), binocular best distance-corrected intermediate visual acuity (VA), and distance contrast sensitivity …
Visual function comparison of 2 aspheric multifocal intraocular lenses
2011
To compare visual function after bilateral implantation of the multifocal Lentis Mplus LS-312 with a nonrotational symmetrical design (copolymer aspheric) or the Acrysof Restor SN6AD1 +3.0 D (hybrid aspheric) intraocular lens (IOL).Fernández-Vega Ophthalmological Institute, Oviedo, Spain.Comparative case series.Six months postoperatively, corrected distance visual acuity (CDVA), distance-corrected near visual acuity (DCNVA), the defocus curve, and photopic and mesopic contrast sensitivity with and without glare were measured.The mean CDVA was 0.02 ± 0.06 (SD) with the copolymer aspheric IOL and -0.06 ± 0.05 logMAR with the hybrid aspheric IOL (P=.07) and the mean DCNVA, 0.10 ± 0.06 and -0.0…
Visual performance comparison between contact lens-based pinhole and simultaneous vision contact lenses.
2011
Background The aim was to evaluate the visual performance provided with a contact lens-based pinhole design against a simultaneous vision multifocal contact lens. Methods In a cross-over study at the University of Valencia, 22 presbyopic patients were evaluated using an artificial pupil fitted on the non-dominant eye and the simultaneous vision PureVision Multifocal contact lenses. After one month of contact lens wear, binocular distance visual acuity (BDVA), binocular near visual acuity (BNVA), defocus curve, binocular distance contrast sensitivity, binocular near contrast sensitivity, and stereoacuity were measured, under photopic conditions (85 cd/m2). In addition, binocular distance vis…
Artificial pupil versus contralateral balanced contact lens fit for presbyopia correction.
2014
Purpose: To assess and compare the effects of contact lens-based artificial pupil design and contralateral balanced multifocal contact lens combination (CBMCLC) on visual performance. Methods: This randomized crossover study conducted at the University of Valencia, Spain included 38 presbyopic patients using an artificial pupil contact lens in the nondominant eye and a CBMCLC. After a month of lens wear, the binocular distance visual acuity (BDVA), binocular near visual acuity (BNVA), defocus curve, binocular distance, and near contrast sensitivity and near stereoacuity (NSA) were measured under photopic conditions (85 cd/m2). Moreover, BDVA and binocular distance contrast sensitivity were …