Search results for " Lenses"
showing 10 items of 190 documents
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…
Visual quality with corneo-scleral contact lenses after intracorneal ring segment (ICRS) implantation for keratoconus management
2019
Purpose: To evaluate the visual quality results when fitting a corneo-scleral contact lens (CScL) after intracorneal ring segment (ICRS) implantation for keratoconus management. Methods: Twenty-seven eyes of 27 patients with keratoconus underwent ICRS implantation and had CScL fitted as their visual quality was unsatisfactory with their spectacles or contact lenses. Patients received a complete eye examination, refraction and visual acuity assessment, anterior eye biomicroscopy, ocular fundus examination, corneal topographic analysis, endothelial-cell count, and visual quality assessment using contrast sensitivity and aberrometry tests. A diagnostic trial set was used in the fitting process…
Posterior‐chamber phakic implantable collamer lenses with a central port: a review
2020
Abstract We aimed to summarize the outcomes reported following the implantation of the V4c implantable collamer lens with a central port (ICL, STAAR Surgical Inc) for myopia correction. A literature search in PubMed, Web of Science and Scopus was carried out to identify publications reporting clinical outcomes of patients who were implanted with the V4c ICL model and had a follow‐up period of at least 6 months. A total of 35 clinical studies published between 2012 and 2020 were included in the present review. A comprehensive analysis of the available data was performed, focusing on visual and refractive outcomes at different time‐points post‐surgery. In addition, adverse events and other pa…
Corneo-scleral contact lens in a piggyback system for keratoconus: A case report.
2017
Purpose: We describe a case of fitting a corneo-scleral contact lens with a multi-aspheric geometry design (MAGD CScL) on top of a daily silicone hydrogel lens (piggyback system) for keratoconus management. Methods: A 48-year-old man using soft toric contact lenses required an improvement in the unsatisfactory quality of his vision. He presented with bilateral asymmetric keratoconus with high myopia in the right eye (RE) and severe myopia in the left eye (LE). In addition, he had low vision in his LE because of a maculopathy. He was fitted with MAGD CScL to correct his irregular astigmatism. A diagnostic trial set was used in the fitting process and the patient was assessed according to a s…
Fitting Scleral Lenses Less Than 15 mm in Diameter: A Review of the Literature.
2020
OBJECTIVE To perform a comprehensive review of the current and historical scientific literature on fitting small scleral lenses (diameter <15 mm) and clarifying their advantages and disadvantages, in addition to their clinical applications. METHODS The literature search was performed through PubMed from MEDLINE. RESULTS Eleven studies of case series (258 eyes) were found. Indications were similar to those of larger scleral lenses, 74% for corneal irregularities (mainly keratoconus), whereas 26% for ocular surface diseases. In the studies on cases of irregular corneas, visual acuity improved significantly regarding the values before and after fitting the lenses (mean, 0.4-0.03 logMar, respec…
Relative Peripheral Myopia Induced by Fractal Contact Lenses
2018
[EN] Purpose: To assess the peripheral refraction induced by Fractal Contact Lenses (FCLs) in myopic eyes by means of a two-dimensional Relative Peripheral Refractive Error (RPRE) map. Materials and Methods: This study involved 26 myopic subjects ranging from -0.50 D to -7.00 D. FCLs prototypes were custom-manufactured and characterized. Corneal topographies were taken in order to assess correlations between corneal asphericity and lens decentration. Two-dimensional RPREs were measured with an open-field autorefractor at 67 points, covering the central 60 x 30 degrees of the visual field. The bidimensional RPRE vector components: M, J(0) and J(45) of the difference between the values obtain…
Effect of multizone refractive multifocal contact lenses on the Cirrus HD OCT retinal measurements
2011
Background Simultaneous vision multifocal contact lenses are widely used to alleviate the symptoms of presbyopia. These contact lenses create simultaneous retinal images due to the incoming light distribution being divided into two or more focuses. Our aim was to evaluate whether the multizone refractive multifocal contact lenses affect the measurements of the retinal nerve fibre layer (RNFL) and macular thickness using optical coherence tomography (OCT). Methods In this cross-over study, 30 eyes of 30 subjects with a mean age of 50.42 ± 7.82 years were fitted with multizone refractive multifocal contact lenses. Using the RNFL Thickness Analysis mode of the Cirrus HD (Carl Zeiss, Meditec, D…
Stereoacuity with balanced presbyopic contact lenses.
2010
Our aim was to evaluate near stereoacuity with the balanced Proclear Multifocal simultaneous vision contact lens. Twenty-five presbyopic subjects were fitted binocularly with the Proclear Multifocal contact lens and with distance contact lenses combined with reading spectacles, which served as controls. After one month, stereoacuity was measured using the vectographic Titmus and Random dot stereotests and the Howard-Dolman (HD) apparatus under photopic conditions (85 cd/m(2) ) at 40 cm. Binocular high-contrast visual acuities (BHCVA) at distance and near were examined. For the multifocal group, mean stereoacuity with the Howard-Dolman method was 22.40 ± 8.23 seconds of arc. Using the Titmus…
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…