20 results match your criteria: "Michigan College of Optometry[Affiliation]"

Importance: Increased myopic shift was found to be associated with 1 year of overminus spectacle treatment for children with intermittent exotropia (IXT). Persistence of myopic shift after discontinuing overminus spectacles is unknown.

Objective: To compare refractive error change over 3 years in children with IXT originally treated with overminus vs nonoverminus spectacles.

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Significance: Binocular summation is a sensitive metric of binocular integration. As such, characterization of the mechanisms underlying binocular summation is a key step in translating and applying this knowledge to abnormal binocular systems afflicted with strabismus and amblyopia.

Purpose: Computational models of binocular summation have advocated the operation of mechanisms sensitive to the interocular phase disparity of first-order carrier gratings.

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Inability to Read After Prolonged COVID-19 Hospitalization: MRI With Clinical Correlation.

J Neuroophthalmol

September 2021

Department of Neurology and Ophthalmology (IB, NL-C, RCS, LN, DK), Michigan State University, East Lansing, Michigan; Department of Radiology (DP-H, BP), Michigan State University, East Lansing, Michigan; and Ferris State University (KA), Michigan College of Optometry, Big Rapids, Michigan.

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IMI - Industry Guidelines and Ethical Considerations for Myopia Control Report.

Invest Ophthalmol Vis Sci

February 2019

Brien Holden Vision Institute, and School of Optometry and Vision Science, University of New South Wales, Sydney, Australia.

Purpose: To discuss guidelines and ethical considerations associated with the development and prescription of treatments intended for myopia control (MC).

Methods: Critical review of published papers and guidance documents was undertaken, with a view to carefully considering the ethical standards associated with the investigation, development, registration, marketing, prescription, and use of MC treatments.

Results: The roles and responsibilities of regulatory bodies, manufacturers, academics, eye care practitioners, and patients in the use of MC treatments are explored.

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Purpose: Letter sequence recognition accuracy has been postulated to be limited primarily by low-level visual factors. The influence of high level factors such as visual memory (load and decay) has been largely overlooked. This study provides insight into the role of these factors by investigating the interaction between letter sequence recognition accuracy, letter string length and report condition.

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Clinical Evaluation of Large Diameter Rigid-Gas Permeable Versus Soft Toric Contact Lenses for the Correction of Refractive Astigmatism. A MultiCenter Study.

Eye Contact Lens

May 2018

École d'optométrie de l'Université de Montréal (L.M.), Montreal, Quebec, Canada; University of Missouri-St. Louis College of Optometry (E.S.B.), St. Louis, MO; Lake Havasu (S.L.W.), AZ; Illinois College of Optometry (R.R., J.S.H.), Chicago, IL; and Michigan College of Optometry (B.W.M., A.D.), Big Rapids, Michigan.

Purpose: This study aims to address the clinical performance of a large diameter rigid gas permeable lens (LRGP) in a group of subjects with low-to-moderate (0.75-2.75 D) refractive astigmatism.

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Binocular capture: the role of non-linear position mechanisms.

Vision Res

September 2014

Michigan College of Optometry, Ferris State University, Big Rapids, MI 49307, USA.

When monocular Vernier targets are presented with binocular disparate elements, an increase in vertical separation elevates alignment thresholds and also shifts its perceived visual direction towards the visual direction of the binocular disparate surround. This observation has been termed binocular capture. There is increasing evidence that this shift in the visual direction of the monocular target may be related to the type of position encoding mechanism involved in processing the relative position signal.

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The influence of binocular disparate targets on the perceived visual direction of adjacent monocular targets has been termed "binocular capture". The magnitude of capture increases significantly with increasing vertical separation between monocular targets. This study sets out to elucidate the interaction between spatial frequency content, contrast polarity and vertical separation between monocular targets to establish the roles of the monocular target's positional uncertainty and the underlying position-encoding mechanism in the production of binocular capture.

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Spatial scaling of the binocular capture effect.

Optom Vis Sci

March 2009

Michigan College of Optometry, Ferris State University, Big Rapids, Michigan, USA.

Purpose: Binocular "capture" occurs when the perceived visual direction of a monocular stimulus is displaced in the direction of the cyclopean visual direction of nearby binocular targets. This effect increases with the vertical separation of broadband monocular stimuli. The present study investigated whether the "capture" effect exhibits a systematic relationship with the spatial frequency composition of monocular lines and vertical separation.

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Background: Motion detection thresholds with a stationary frame of reference are significantly lower than unreferenced motion thresholds. To account for this, previous studies have postulated the existence of compensatory mechanisms, driven by the presence of a surround, that cancel the effects of eye movements. In the present study we used an adaptive optics scanning laser ophthalmoscope (AOSLO) to investigate the effects of retinal jitter due to fixation eye movements on referenced and unreferenced motion thresholds.

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Background: Nonorganic vision loss (NOVL) usually refers to reports of acuity reduction, field constrictions, or both without any associated organic pathology. Regardless of the underlying cause, the primary concern of the eye care practitioner is to demonstrate visual potential better than suggested by the patient's subjective reports.

Case Report: This article presents a case report of a 43-year-old woman with NOVL.

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Binocular contrast interactions in two-frame motion discrimination.

Percept Psychophys

August 2007

Michigan College of Optometry, Ferris State University, Big Rapids, Michigan 49307, USA.

Previous studies have shown that two-frame motion detection thresholds are elevated if one frame's contrast is raised, despite the increase in average contrast--the "contrast paradox". In this study, we investigated if such contrast interactions occurred at a monocular or binocular site of visual processing. Two-frame motion direction discrimination thresholds were measured for motion frames that were presented binocularly, dichoptically or interocularly.

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Background: This prospective case series was conducted to describe the safety and efficacy of orthokeratology with the Emerald Contact Lens for Overnight Orthokeratology (Oprifocon A; Euclid Systems Corporation, Herndon, Virginia) among young myopes.

Methods: Twenty subjects (ages 10 to 16) were enrolled in the 6-month pilot study. Subjects were fit empirically with overnight orthokeratology lenses and evaluated at 1 day, 1 week, 1 month, 2 months, 3 months, and 6 months.

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Army, Navy, and Air Force safety center ground eye injuries were evaluated from fiscal year 1988 through fiscal year 1998. The U.S.

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Stereopsis from a performance perspective.

Optom Vis Sci

March 2005

Michigan College of Optometry, Ferris State University, Big Rapids, Michigan, USA.

Purpose: A patient can demonstrate a poor stereoscopic test or task performance for reasons inherent within the test/task itself for reasons dependent on normal physiology common to all human subjects, and also for reasons that are outside of normal physiology and are unique or idiosyncratic to a particular person's visual system. This article reviews the literature for the first two reasons, but emphasizes the pathophysiology involved in the idiosyncratic and abnormal reasons.

Results: Using control systems analysis, it is shown that deficits in stereoscopic performance can be explained by reference to the quantitative aspect of stereoscopic threshold and qualitative aspects such as speed of response, reliability-robustness, and strength of percept.

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A retrospective study reviewed medical records of military personnel who had participated in a vision readiness study the previous year. The review evaluated (1) the number of personnel who returned for an eye examination (as recommended), (2) the number of dilated eye examinations, (3) the number of optical devices ordered, (4) the number of patients requiring continuing treatment, (5) the types of eye disease in personnel who were classified as nondeployable in the original study, and (6) the relationship between patient vision complaints and the need for spectacles. Analyses revealed 44% of military personnel have never had a comprehensive eye examination.

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The Association of Vision Science Librarians' citation analysis of Duane's Clinical Ophthalmology.

J Med Libr Assoc

January 2003

Michigan College of Optometry Reading Room, Ferris State University, 1310 Cramer Circle, Big Rapids, Michigan 49307-2738, USA.

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Relation between anterior and posterior converter systems.

Optom Vis Sci

July 2002

Michigan College of Optometry, Ferris State University, Big Rapids 49307-2738, USA.

A corrected or uncorrected human eye may be astigmatic and noncoaxial. The first-order (i.e.

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Asymmetric dioptric power matrices and corresponding thick lenses.

Optom Vis Sci

June 1997

Michigan College of Optometry, Ferris State University, Big Rapids, USA.

Background: When thickness or separation is taken into account, the dioptric power of systems with obliquely crossed toric surfaces (OCTS), including some corrected and uncorrected human eyes, can be represented by a four-dimensional vector space, provided that an arbitrary 2 x 2 asymmetric matrix is the equivalent power matrix of some optical system. The provision is crucial for the statistical validity of dioptric power matrix methods that take account of thickness. Previous efforts to verify the provision have not been satisfactory.

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Equivalent dioptric power asymmetry relations for thick astigmatic systems.

Optom Vis Sci

June 1997

Michigan College of Optometry, Ferris State University, Big Rapids, USA.

For optical systems consisting of separated obliquely crossed toric interfaces, the equivalent dioptric power has principal meridians that are not necessarily orthogonal to each other. In this case it takes four parameters to specify the equivalent power. A set of parameters convenient for ophthalmic optics consists of three traditional spherocylindrical parameters SC x theta together with a dioptric asymmetry parameter g.

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