Search results for "visio"

Long-term results of surgical treatment of high myopia with Worst-Fechner intraocular lenses

1995

Abstract This retrospective study evaluated the results in 90 eyes that had a minus-power anterior chamber intraocular lens implanted to correct high myopia. Preoperative myopia ranged from −7.00 to −24.00 D. Postoperative spherical equivalent was −0.50 D; 80.5% of eyes were within 1.00 D of emmetropia. Two years postoperatively, no cataract formation, retinal detachment, glaucoma, or significant endothelial damage had occurred. We conclude that minus-power lenses can rapidly, safely, and predictably correct high myopia in phakic patients.

Excimer laser photorefractive keratectomy for high myopia

1995

Abstract One hundred and thirty-three eyes of 103 patients had photorefractive keratectomy with a slit scan mode excimer laser for myopia ranging from −6.00 to −22.00 diopters (D). The epithelium was removed with 20% ethanol, and the ablation was done with a tapered profile surrounding the optical zone. Patients were divided into two groups based on preoperative myopia: Group A, −6.00 D to −12.00 D (88 eyes); Group B, −12.50 D to −22.00 D (45 eyes). In Group A, mean preoperative refraction was −9.59 ± 1.79 D. Mean postoperative refraction was −0.29 ± 1.47 D at one month, −0.85 ± 1.68 D at three months, −1.17 ± 2.04 D at six months, and −0.56 ± 0.74 D at one year. Anterior stromal haze was g…

Prevalence of corneal astigmatism before cataract surgery.

2008

To analyze the prevalence and presentation patterns of corneal astigmatism in cataract surgery candidates.University of Valencia, Valencia, Spain.Refractive and keratometric values were measured before surgery in patients having cataract extraction. Descriptive statistics of refractive and keratometric cylinder data were analyzed and correlated by age ranges.Refractive and keratometric data from 4,540 eyes of 2,415 patients (mean age 60.59 years +/- 9.87 [SD]; range 32 to 87 years) differed significantly when the patients were divided into 10-year subsets. There was a trend toward less negative corneal astigmatism values, except the steepest corneal radius and the J(45) vector component, in…

Endothelial study of iris-claw phakic lens: four year follow-up.

1998

Abstract Purpose: To study quantitative and morphometric endothelial changes in phakic eyes implanted with the Worst iris-claw lens to correct high myopia. Setting: Department of Ophthalmology, University Hospital “La Fe”, Valencia, Spain. Material and Methods: This retrospective study involved 111 phakic eyes (73 patients) implanted with the Worst iris-claw lens. Noncontact specular microscopy and computer-assisted analysis was performed preoperatively and 6 months and 1, 2, 3, and 4 years postoperatively. Results: The mean cell loss was 3.85% at 6 months, 6.59% at 1 year, 9.22% at 2 years, 11.68% at 3 years, and 13.42% at 4 years. At 2 years, the hexagonality and coefficient variation in …

Flicker Defined Form Perimetry in Glaucoma Suspects with Normal Achromatic Visual Fields

2014

To evaluate if repeated flicker-defined form (FDF) perimetry can detect visual field (VF) defects in glaucoma suspects with normal findings in achromatic standard automated perimetry (SAP).Patients with optic nerve heads (ONHs) or retinal nerve fiber layer (RNFL) findings clinically suspicious for glaucoma and normal SAP were enrolled. Patients underwent VF testing with FDF perimetry (Heidelberg Edge Perimetry, HEP) at two consecutive visits (HEP I and HEP II) and confocal scanning laser ophthalmoscopy with the Heidelberg Retina Tomograph (HRT). Abnormal HEP was defined by cluster-point analysis (CPA) and by the HEP specific glaucoma hemi-field test (GHT). Results were compared with an age-…

Differentiating the differential rotation effect.

2011

As an observer views a picture from different viewing angles, objects in the picture appear to maintain their orientation relative to the observer. For instance, the eyes of a portrait appear to follow the observer as he or she views the image from different angles. We have explored this rotation effect, often called the Mona Lisa effect. We report three experiments that used portrait photographs to test variations of the Mona Lisa effect. The first experiment introduced picture displacements relative to the observer in directions beyond the horizontal plane. The Mona Lisa effect remained robust for vertical and/or diagonal observer displacements. The experiment also included conditions in …

Visual gravity influences arm movement planning.

2012

International audience; When submitted to a visuomotor rotation, subjects show rapid adaptation of visually guided arm reaching movements, indicated by a progressive reduction in reaching errors. In this study, we wanted to make a step forward by investigating to what extent this adaptation also implies changes into the motor plan. Up to now, classical visuomotor rotation paradigms have been performed on the horizontal plane, where the reaching motor plan in general requires the same kinematics (i.e., straight path and symmetric velocity profile). To overcome this limitation, we considered vertical and horizontal movement directions requiring specific velocity profiles. This way, a change i…

Testing the egocentric mirror-rotation hypothesis.

2011

AbstractAlthough observers know about the law of reflection, their intuitive understanding of spatial locations in mirrors is often erroneous. Hecht et al. (2005) proposed a two-stage mirror-rotation hypothesis to explain these misconceptions. The hypothesis involves an egocentric bias to the effect that observers behave as if the mirror surface were rotated by about 2° to be more orthogonal than is the case. We test four variants of the hypothesis, which differ depending on whether the virtual world, the mirror, or both are taken to be rotated. We devised an experimental setup that allowed us to distinguish between these variants. Our results confirm that the virtual world — and only the v…

Prevalence of visual problems in a rural population of Kenya

2012

Salmonella-reactive Synovial Fluid T-cell Clones in a Patient with Post-infectious Salmonella Arthritis

1990

From a patient with reactive arthritis following Salmonella typhimurium enteritis, synovial fluid T-lymphocytes were cloned and expanded in vitro. Seven out of 74 clones showed a marked proliferative response to antigens of heat-killed Salmonella typhimurium with autologous T-cell-depleted peripheral blood mononuclear cells as antigen-presenting cells. The Salmonella-reactive clones were of the CD4+ phenotype, antigen-induced proliferation could be inhibited by a monoclonal antibody to HLA class II. One clone recognized both Salmonella and Campylobacter jejuni antigens in the proliferation assay. The multiclonality of Salmonella-reactive synovial fluid T-cells indicates that the microorgani…