keyword
MENU ▼
Read by QxMD icon Read
search

Vergence

keyword
https://www.readbyqxmd.com/read/28540011/effectiveness-of-vision-therapy-in-school-children-with-symptomatic-convergence-insufficiency
#1
Jung Un Jang, Jung Yun Jang, Kim Tai-Hyung, Hwang Woon Moon
PURPOSE: To determine the effectiveness of vision therapy among Korean elementary school children with convergence insufficiency. METHODS: A total of 235 elementary schoolchildren, 10.13 ± 2.45 years of age, were subjected to thorough eye examination including binocular vision testing. Of them, 32 individuals with symptomatic convergence insufficiency without strabismus, amblyopia, and ocular disease were chosen to receive vision therapy via brock string, barrel card, mirror stereoscope, prism goggles, and aperture rule for a duration of 8 weeks...
April 2017: Journal of Ophthalmic & Vision Research
https://www.readbyqxmd.com/read/28532935/toric-outcomes-computer-assisted-registration-versus-intraoperative-aberrometry
#2
Jonathan D Solomon, John Ladas
PURPOSE: To compare refractive outcomes of intraoperative computer-assisted registration and intraoperative aberrometry for the reduction of cylinder during toric intraocular lens (IOL) placement. SETTING: Bowie Vision Institute, Bowie, Maryland, USA. DESIGN: Prospective randomized case series. METHOD: The patients were divided into 2 groups that had toric IOL implantation after phacoemulsification. The intraoperative computer-assisted registration group (Group 1) had preoperative toric calculations...
April 2017: Journal of Cataract and Refractive Surgery
https://www.readbyqxmd.com/read/28522252/optical-quality-of-rotationally-symmetrical-contact-lenses-derived-from-their-power-profiles
#3
Antonio J Del Águila-Carrasco, Daniel Monsálvez-Romín, Eleni Papadatou
PURPOSE: To present a methodology for evaluating the optical quality of rotationally symmetrical contact lenses (CLs) from a single power profile. METHODS: Simulated rotationally symmetrical power profiles corresponding to different CLs designs (monofocal, two-zone center-near bifocal, and four-zone center-distance bifocal) were used to calculate the wavefront error profile by means of numerical integration. Then, each lens wavefront error profile was spun around the center to obtain the lens wavefront error surface...
May 15, 2017: Contact Lens & Anterior Eye: the Journal of the British Contact Lens Association
https://www.readbyqxmd.com/read/28514944/short-term-visual-outcomes-of-a-new-trifocal-intraocular-lens
#4
Jorge L García-Pérez, Juan Gros-Otero, Celia Sánchez-Ramos, Vanesa Blázquez, Inés Contreras
BACKGROUND: Today, patients often expect to achieve spectacle independance after cataract surgery. New trifocal intraocular lenses have been developed to try and fullfill this demand. The purpose of this study is to report the short-term visual outcomes of a new trifocal intraocular lens (AcrySof PanOptix™). METHODS: Consecutive adult patients undergoing cataract surgery with bilateral implantation of the study intraocular lens in a private practice clinic were considered for inclusion...
May 17, 2017: BMC Ophthalmology
https://www.readbyqxmd.com/read/28505662/asymmetries-between-convergence-and-divergence-reveal-tonic-vergence-is-dependent-upon-phasic-vergence-function
#5
Ian M Erkelens, William R Bobier
Horizontal vergence eye movements are controlled by two processes, phasic and slow-tonic. Slow-tonic responses are hypothesized to be stimulated by the faster, pulse-step neural output of the phasic system. This suggests that the general behavior of each system should be similar; however, this relationship has yet to be investigated directly. We characterize the relationship between phasic and tonic vergence by quantifying directional asymmetries in the response properties of each mechanism to the same disparity amplitudes...
May 1, 2017: Journal of Vision
https://www.readbyqxmd.com/read/28499997/enhancement-of-visual-comfort-and-sense-of-presence-on-stereoscopic-3d-images
#6
Heeseok Oh, Jongyoo Kim, Jinwoo Kim, Taewan Kim, Sanghoon Lee, Alan C Bovik
Conventional stereoscopic 3D (S3D) displays do not provide accommodation depth cues of the 3D image or video contents being viewed. The sense of content depths is thus limited to cues supplied by motion parallax (for 3D video), stereoscopic vergence cues created by presenting left and right views to the respective eyes, and other contextual and perspective depth cues. The absence of accommodation cues can induce two kinds of accommodation vergence mismatches (AVM) at the fixation and peripheral points, which can result in severe visual discomfort...
May 9, 2017: IEEE Transactions on Image Processing: a Publication of the IEEE Signal Processing Society
https://www.readbyqxmd.com/read/28491916/orthoptic-treatment-of-convergence-insufficiency-in-parkinson-s-disease-a-case-series
#7
Hélène Kergoat, Caroline Law, Estefania Chriqui, Marie-Jeanne Kergoat, Bernard-Simon Leclerc, Michel Panisset, Ronald Postuma, Elizabeth L Irving
Introduction: This study reports a case series of orthoptic treatment (OT) for convergence insufficiency (CI) in individuals with Parkinson's disease (PD). Method: We are reporting two cases of individuals with PD who completed OT for CI. Both had a confirmed diagnosis of CI, accompanied by CI-type symptomatology. They each underwent an OT program consisting of three office-based visits and 8 weeks of home-based exercises. Treatment outcome was based on the changes measured pre- versus post-OT on the near point of convergence, positive fusional vergences, and symptomatology score...
January 2017: Gerontology & Geriatric Medicine
https://www.readbyqxmd.com/read/28439978/simulation-of-commercial-vs-theoretically-optimised-contact-lenses-for-presbyopia
#8
Richard Legras, David Rio
PURPOSE: To compare theoretically optimised bifocal contact lens optical designs to commercially available optical designs for presbyopia. METHODS: Retinal images were simulated, using a numerical eye model, from -6 (i.e., near vision) to +2 D for each 0.25 D. Ten optical profiles were simulated. Four of them corresponded to commercial contact lenses (i.e., Acuvue Oasys for Presbyopia®, Air Optix Aqua Multifocal®, Purevision Multifocal® and Distance Biofinity Multifocal®)...
May 2017: Ophthalmic & Physiological Optics: the Journal of the British College of Ophthalmic Opticians (Optometrists)
https://www.readbyqxmd.com/read/28424868/non-invasive-measurements-of-the-dynamic-changes-in-the-ciliary-muscle-crystalline-lens-morphology-and-anterior-chamber-during-accommodation-with-a-high-resolution-oct
#9
José J Esteve-Taboada, Alberto Domínguez-Vicent, Daniel Monsálvez-Romín, Antonio J Del Águila-Carrasco, Robert Montés-Micó
PURPOSE: The purpose of the study was to assess non-invasively the changes in the anterior chamber eye, crystalline lens morphology, and ciliary muscle during accommodation by means of an anterior chamber optical coherence tomographer (OCT), and correlate them with vergence. METHODS: Twenty-five eyes of twenty-five healthy subjects, whose mean age was 29.9±7.1 years, were included and measured with an anterior chamber OCT. The central corneal thickness (CCT), anterior chamber depth (ACD), anterior crystalline lens radius of curvature (ALRC), crystalline lens thickness (CLT), and ciliary muscle area (CMA) were measured for each participant at 0, -1, -2, and -3 D of target vergence...
April 20, 2017: Graefe's Archive for Clinical and Experimental Ophthalmology
https://www.readbyqxmd.com/read/28380953/compact-see-through-3d-head-mounted-display-based-on-wavefront-modulation-with-holographic-grating-filter
#10
Qiankun Gao, Juan Liu, Xinhui Duan, Tao Zhao, Xin Li, Peilin Liu
A compact see-through three-dimensional head-mounted display (3D-HMD) is proposed and investigated in this paper. Two phase holograms are analytically extracted from the object wavefront and uploaded on different zones of the spatial light modulator (SLM). A holographic grating is further used as the frequency filter to couple the separated holograms together for wavefront modulation. The developed preliminary prototype has a simple optical facility and a compact structure (133.8mm × 40.4mm × 35.4mm with a 47...
April 3, 2017: Optics Express
https://www.readbyqxmd.com/read/28380093/assessing-the-accommodation-response-after-near-visual-tasks-using-different-handheld-electronic-devices
#11
Aikaterini I Moulakaki, Alberto Recchioni, Antonio J Del Águila-Carrasco, José J Esteve-Taboada, Robert Montés-Micó
Purpose: To assess the accommodation response after short reading periods using a tablet and a smartphone as well as determine potential differences in the accommodation response at various stimulus vergences using a Hartmann- Shack aberrometer. Methods: Eighteen healthy subjects with astigmatism of less than 1 D, corrected visual acuity of 20/20 or better, and normal findings in an ophthalmic examination were enrolled. Accommodation responses were obtained under three different conditions: accommodation system of the eye relaxed and visually stressed with a tablet and an smartphone for 10 min, at a distance of 0...
January 2017: Arquivos Brasileiros de Oftalmologia
https://www.readbyqxmd.com/read/28355633/combining-1-d-components-to-extract-pattern-information-it-is-about-more-than-component-similarity
#12
Christian Quaia, Lance M Optican, Bruce G Cumming
At least under some conditions, plaid stimuli are processed by combining information first extracted in orientation and scale-selective channels. The rules that govern this combination across channels are only partially understood. Although the available data suggests that only components having similar spatial frequency and contrast are combined, the extent to which this holds has not been firmly established. To address this question, we measured, in human subjects, the short-latency reflexive vergence eye movements induced by stereo plaids in which spatial frequency and contrast of the components are independently varied...
March 1, 2017: Journal of Vision
https://www.readbyqxmd.com/read/28348893/effect-of-illumination-on-ocular-status-modifications-induced-by-short-term-3d-tv-viewing
#13
Yuanyuan Chen, Yuwen Wang, Xinping Yu, Aiqin Xu, Jian Jiang, Hao Chen
Objectives. This study aimed to compare changes in ocular status after 3D TV viewing under three modes of illumination and thereby identify optimal illumination for 3D TV viewing. Methods. The following measures of ocular status were assessed: the accommodative response, accommodative microfluctuation, accommodative facility, relative accommodation, gradient accommodative convergence/accommodation (AC/A) ratio, phoria, and fusional vergence. The observers watched 3D television for 90 minutes through 3D shutter glasses under three illumination modes: A, complete darkness; B, back illumination (50 lx); and C, front illumination (130 lx)...
2017: Neural Plasticity
https://www.readbyqxmd.com/read/28324117/accommodation-responds-to-optical-vergence-and-not-defocus-blur-alone
#14
Antonio J Del Águila-Carrasco, Iván Marín-Franch, Paula Bernal-Molina, José J Esteve-Taboada, Philip B Kruger, Robert Montés-Micó, Norberto López-Gil
Purpose: To determine whether changes in wavefront spherical curvature (optical vergence) are a directional cue for accommodation. Methods: Nine subjects participated in this experiment. The accommodation response to a monochromatic target was measured continuously with a custom-made adaptive optics system while astigmatism and higher-order aberrations were corrected in real time. There were two experimental open-loop conditions: vergence-driven condition, where the deformable mirror provided sinusoidal changes in defocus at the retina between -1 and +1 diopters (D) at 0...
March 1, 2017: Investigative Ophthalmology & Visual Science
https://www.readbyqxmd.com/read/28241657/dynamic-visual-responses-of-accommodation-and-vergence-to-electro-holographic-images
#15
Aya Nozaki, Masaya Mitobe, Fumio Okuyama, Yuji Sakamoto
Electro-holography can display images without inducing fatigue and three-dimensional (3D) sickness, i.e., visual discomfort due to viewing a stereoscopic display. Thus, this technology is expected to be applied to 3D media. However, there are no studies that have shown the agreement between the dynamic responses of accommodation and vergence to the reconstructed images of electro-holography and those to the real targets. This paper describes the measurement results of these responses using a developed system that can simultaneously measure the dynamic responses of accommodation and vergence...
February 20, 2017: Optics Express
https://www.readbyqxmd.com/read/28222490/the-prevalence-of-convergence-insufficiency-in-iran-a-population-based-study
#16
Hassan Hashemi, Payam Nabovati, Mehdi Khabazkhoob, Hadi Ostadimoghaddam, Asgar Doostdar, Ehsan Shiralivand, Abbasali Yekta
PURPOSE: The aim was to determine the prevalence of convergence insufficiency and its relationship with age, gender and refractive error in a population-based study. METHODS: In this cross-sectional study, all residents over one year old in Mashhad city, in the north east of Iran, were sampled through random stratified cluster sampling. After selecting samples and their participation in the study, they all had eye examinations including the measurement of visual acuity, refraction, binocular vision assessment, including cover test, measurement of near point of convergence and fusional vergences and finally, slitlamp biomicroscopy...
February 21, 2017: Clinical & Experimental Optometry: Journal of the Australian Optometrical Association
https://www.readbyqxmd.com/read/28195951/assessment-of-oculomotor-function-in-patients-with-postconcussion-syndrome-a-systematic-review
#17
Foad Taghdiri, Brenda Varriano, Maria Carmela Tartaglia
BACKGROUND: Concussion and its associated sequel, postconcussion syndrome (PCS), have a debilitating impact on the lives of concussed patients. However, a diagnostic biomarker for this condition is lacking. Recently, there has been a surge of interest in using oculomotor function testing as an objective assessment of patients with PCS. OBJECTIVES: To systematically synthesize, appraise, and summarize all published empirical studies that have assessed alteration of oculomotor functions in patients with PCS...
February 10, 2017: Journal of Head Trauma Rehabilitation
https://www.readbyqxmd.com/read/28192091/the-influence-of-age-on-adaptation-of-disparity-vergence-and-phoria
#18
Tara L Alvarez, Eun H Kim, Chang Yaramothu, Bérangère Granger-Donetti
A paucity of research exists to investigate whether the normal aging process influences the ability to adapt disparity vergence and phoria. Vergence eye movements and dissociated phoria were recorded from 49 healthy subjects (ages 20-70years) using an objective eye movement tracking system. Four-degree vergence responses were modified using a double-step protocol. Dynamics of vergence were quantified via peak velocity. The phoria adaptation experiment measured the magnitude (net change in phoria level) and rate (magnitude divided by the time constant) of phoria adaption during 5min of sustained fixation on a binocular target (40cm/8...
February 16, 2017: Vision Research
https://www.readbyqxmd.com/read/28177529/a-central-mesencephalic-reticular-formation-projection-to-medial-rectus-motoneurons-supplying-singly-and-multiply-innervated-extraocular-muscle-fibers
#19
Martin O Bohlen, Susan Warren, Paul J May
We recently demonstrated a bilateral projection to the supraoculomotor area from the central mesencephalic reticular formation (cMRF), a region implicated in horizontal gaze changes. C-group motoneurons, which supply multiply innervated fibers in the medial rectus muscle, are located within the primate supraoculomotor area, but their inputs and function are poorly understood. Here, we tested whether C-group motoneurons in Macaca fascicularis monkeys receive a direct cMRF input by injecting this portion of the reticular formation with anterograde tracers in combination with injection of retrograde tracer into the medial rectus muscle...
June 1, 2017: Journal of Comparative Neurology
https://www.readbyqxmd.com/read/28176802/ocular-reflex-phase-during-off-vertical-axis-rotation-in-humans-is-modified-by-head-turn-on-trunk-position
#20
Samantha B Douglas, Gilles Clément, Pierre Denise, Scott J Wood
Constant velocity Off-Vertical Axis Rotation (OVAR) imposes a continuously varying orientation of the head and body relative to gravity, which generates a modulation of horizontal (conjugate and vergence), vertical, and torsional eye movements. We introduced the head-turn-on-trunk paradigm during OVAR to examine the extent to whether the modulation of these ocular reflexes is mediated by graviceptors in the head, i.e., otoliths, versus other body graviceptors. Ten human subjects were rotated in darkness about their longitudinal axis 20° off-vertical at a constant velocity of 45 and 180°/s, corresponding to 0...
February 8, 2017: Scientific Reports
keyword
keyword
37009
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"