Binocular vision

Induction of a central retinal lesion in both eyes of adult mammals is a model for macular degeneration and leads to retinotopic map reorganization in the primary visual cortex (V1). Here we characterized the spatio-temporal dynamics of molecular activity levels in the central and peripheral representation of five higher order visual areas, V2/18, V3/19, V4/21a,V5/PMLS, area 7, and V1/17, in adult cats with central 10° retinal lesions (both sexes), by means of real-time PCR for the neuronal activity reporter gene zif268...

PURPOSE: To compare minimally invasive strabismus surgery (MISS) with conventional strabismus surgery for horizontal recti in terms of functional outcome and complications. METHODS: A total of 40 patients requiring surgery for horizontal recti were divided into two groups: those undergoing MISS and those operated on using the conventional limbal technique. In the MISS group, two small keyhole radial cuts were made superior and inferior to the insertion of the muscle margin...

A bio-micromanipulation system is designed for manipulating micro-objects with a length scale of tens or hundreds of microns based on stereo light microscope. The world coordinate reconstruction of points on the surface of micro-objects is an important goal for the micromanipulation. Traditional pinhole camera model is applied widely in macrocomputer vision. However, this model will output bad data with remarkable error if it is directly used to reconstruct three-dimensional world coordinates for stereo light microscope...

PURPOSE: To compare visual outcomes and performance between bilateral implantation of a diffractive trifocal intraocular lens (IOL) Acrysof(®)PanOptix(®) TFNT00 and blended implantation of two different near add power bifocal IOLs: Acrysof(®) Restor(®) SV25T0 in dominant eye and Acrysof(®) Restor(®) SN6AD1 in the nondominant eye. METHODS: This prospective, nonrandomized, consecutive and comparative study assessed 20 patients (40 eyes) who had bilateral cataract surgery performed using the IOLs described...

BACKGROUND: To evaluate the effects on near and intermediate visual performance after bilateral Laser Anterior Ciliary Excision (LaserACE) procedure. METHODS: LaserACE surgery was performed using the VisioLite 2.94 μm erbium: yttrium-aluminum-garnet (Er:YAG) ophthalmic laser system in 4 oblique quadrants on the sclera over the ciliary muscle in 3 critical zones of physiological importance (over the ciliary muscles and posterior zonules) with the aim to improve natural dynamic accommodative forces...

AIM: The aim of the study was to evaluate color vision and its diagnostic value in predicting the risk of diabetic retinopathy in patients with glucose metabolism disorders. MATERIALS AND METHODS: The study involved 197 people, 92 women and 105 men aged 63.21 ± 8.74 years. In order to assess glucose metabolism disorders, patients were divided into three groups. The first group (DM) consisted of 60 people (16 women and 44 men aged 61.92 ± 8.46 years). These were people with type 2 diabetes...

BACKGROUND: Besides the reduction of visual field size, hemianopic patients may also experience other poorly understood symptoms such as blurred vision, diplopia, or reduced visual acuity, which may be related to microsaccade function. OBJECTIVE: To determine (i) if microsaccades are altered in hemianopia; (ii) how altered microsaccade features correlate with visual performances; and (iii) how their direction relates to visual field defect topography. METHODS: In this case-control study, microsaccades of hemianopic stroke patients (n = 14) were assessed with high-resolution eye-tracking technique, compared with those of healthy controls (n = 14), and correlated with visual performances, visual field defect parameters and lesion age...

PURPOSE: To determine changes in stereoacuity in anisometropic myopic eyes after photorefractive keratectomy (PRK). METHODS: Myopic patients with at least 1 diopter (D) of anisometropia in sphere, astigmatism, or spherical equivalent who were referred to our hospital for excimer refractive surgery were enrolled as a prospective sequential interventional case series. All patients underwent wavefront-guided photorefractive keratectomy (WFG-PRK) using the Technolas Perfect Vision (217z) Excimer laser machine...

Vision and hearing are dependent on disparities of spatial patterns received by two eyes and on time and intensity differences to two ears. However, the experiences of a single world have masked attention to these disparities. While eyes and ears are paired, there has not been parity in the attention directed to their functioning. Phenomena involving binocular vision were commented upon since antiquity whereas those about binaural hearing are much more recent. This history is compared with respect to the experimental manipulations of dichoptic and dichotic stimuli and the instruments used to stimulate the paired organs...

In amblyopia, abnormal visual experience leads to an extreme form of eye dominance, in which vision through the non-dominant eye is degraded. A key aspect of this disorder is perceptual suppression: The image seen by the stronger eye often dominates during binocular viewing, blocking the weaker eye's image from reaching awareness. Interocular suppression is the focus of ongoing work aimed at understanding and treating amblyopia, yet its physiological basis remains unknown. We measured binocular interactions in visual cortex of anesthetized amblyopic monkeys (female Macaca nemestrina), using 96-channel 'Utah' arrays to record from populations of neurons in V1 and V2...

PURPOSE: This study sought to explore the practice of orthoptists internationally in care provision for poststroke visual impairment. METHODS: Survey questions were developed and piloted with clinicians, academics, and users. Questions addressed types of visual problems, how these were identified, treated, and followed up, care pathways in use, links with other professions, and referral options. The survey was approved by the institutional ethical committee. The survey was accessed via a web link that was circulated through the International Orthoptic Association member professional organisations to orthoptists...

PURPOSE: The stability of binocular vision depends upon good fusional amplitudes, but the clinical assessment of fusional amplitudes varies around the world. The purpose of this study was to determine whether or not there is variation in the assessment of fusional amplitudes in normal subjects. The author looked at the testing distance, the order of testing, the role of examiner encouragement, and the subject's level of alertness. METHODS: In a prospective study using a modified crossover design, the author assessed fusional amplitudes in 99 subjects with normal eye exams...

The visual system must recover important properties of the external environment if its host is to survive. Because the retinae are effectively twodimensional but the world is three-dimensional (3D), the patterns of stimulation both within and across the eyes must be used to infer the distal stimulus-the environment-in all three dimensions. Moreover, animals and elements in the environment move, which means the input contains rich temporal information. Here, in addition to reviewing the literature, we discuss how and why prior work has focused on purported isolated systems (e...

In amblyopia, a visual disorder caused by abnormal visual experience during development, the amblyopic eye loses visual sensitivity while the other (fellow) eye is largely unaffected. Binocular vision in amblyopes is often disrupted by interocular suppression. We used 96-electrode arrays to record neurons and neuronal groups in areas V1 and V2 of 6 female monkeys (Macaca nemestrina) made amblyopic by artificial strabismus or anisometropia in early life, as well as 2 visually normal female monkeys (Macaca nemestrina)...

SIGNIFICANCE: The Bifocal Lenses In Nearsighted Kids (BLINK) study is the first soft multifocal contact lens myopia control study to compare add powers and measure peripheral refractive error in the vertical meridian, so it will provide important information about the potential mechanism of myopia control. PURPOSE: The BLINK study is a National Eye Institute-sponsored, double-masked, randomized clinical trial to investigate the effects of soft multifocal contact lenses on myopia progression...

PURPOSE: To compare the visual outcomes and quality of vision of 2 new diffractive multifocal intraocular lenses (IOLs) with those of a monofocal IOL. SETTING: Fatebenefratelli e Oftalmico Hospital, Milan, Italy. DESIGN: Prospective case series. METHODS: Patients had bilateral cataract surgery with implantation of a trifocal IOL (Panoptix), an extended-range-of-vision IOL (Symfony), or a monofocal IOL (SN60WF). Postoperative examinations included assessing distance, intermediate, and near visual acuity; binocular defocus; intraocular and total aberrations; point-spread function (PSF); modulation transfer function (MTF); retinal straylight; and quality-of-vision (QoV) and spectacle-dependence questionnaires...

AIM: To determine age norms in the first three years of life for grating visual acuity and contrast sensitivity obtained with Lea grating test and Hiding Heidi low contrast face test. METHODS: Lea grating test was used to estimate binocular grating acuity and Hiding Heidi low contrast face test was used to estimate contrast sensitivity in 600 healthy infants and children. Age ranged from 3 to 36mo subdivided into 12 groups subjected for full ophthalmologic and pediatric examinations...

Purpose: The measurement of achromatic sensitivity has been an important tool for monitoring subtle changes in vision as the result of disease or response to therapy. In this study, we aimed to provide a normative data set for achromatic and chromatic contrast sensitivity functions within a common cone contrast space using an abbreviated measurement approach suitable for clinical practice. In addition, we aimed to provide comparisons of achromatic and chromatic binocular summation across spatial frequency...

Understanding which aspects of vision are related to falls is important. We examine the associations between tests of balance, mobility, fear of falling (FES-1) and aspects of vision in 72 adults aged 70+. Balance and mobility were examined using the One Legged Stance test (OLST), the Sit to Stand test (STST) and the 5 Meter Walking test (5MWT). Visual measures included visual acuity (VA), contrast sensitivity, stereoacuity, binocular vision (BV) measurements, Useful field of View (UFV) and Attended Field of View (AFOV)...

In social interactions, it is highly salient to us where other people are looking. The ability to recover this information is critical to typical social development, helping us to coordinate our attention and behavior with others and understand their intentions and mental states [1-3]. The depth and direction in which another individual is fixating are specified jointly by their head position, eye deviation, and binocular vergence [4, 5]. It is hereto unknown, however, whether this dynamic visual information about others' focus of attention affects how we ourselves see the world...