摘要:

Stereopsis performance was assessed in 88 optometric patients using an operant match-to-sample discrimination task involving random dot stereograms (RDSs). All normals passed the RDS test, and all constant strabismics without amblyopia, microtropes, and amblyopic strabismics failed. Only a portion of anisometropia amblyopes, intermittent strabismics, and ocular-pathology patients passed. The findings were interpreted as indicating that stereopsis with a RDS may be better predicted and explained in terms of binocular fusion and bifoveal alignment than by visual acuity.

ISSN:0093-7002    

出版商:OVID    

年代:1978

数据来源: OVID

摘要:

This paper examines the contribution of the macular region to visual function. Several test targets were used to measure visual performance within 10 deg of the center of the fovea for normal observers and for an observer with a uniocular central 6-deg scotoma. We conclude that the nature of the test target is more important in the measurement of parafoveal than central vision and that the macular region contributes significantly to the visibility of objects as large as 2.5 deg.

ISSN:0093-7002    

出版商:OVID    

年代:1978

数据来源: OVID

摘要:

This paper describes the various parts of a new interactive classroom television system (ICTS) that is being used by partially sighted elementary school children. This ICTS permits children to view one of seven separately controlled TV screens and thereby be in continuous visual communication with their teacher, classmates, and classroom. Comments are made on the advantages of educating partially sighted children separately from normally sighted children.

ISSN:0093-7002    

出版商:OVID    

年代:1978

数据来源: OVID

摘要:

A color-naming task was used to assess color vision in the fovea and parafovea. Like traditional psychophysical procedures, color naming showed that short-wavelength vision is suppressed centrally. The anatomical and physiological mechanisms underlying tritan foveal vision are discussed.

ISSN:0093-7002    

出版商:OVID    

年代:1978

数据来源: OVID

摘要:

We show the presence of a new nonlinearity in accommodation dynamics. Positive accommodation is slower when the eye is operating in the near range; conversely, relaxation of accommodation is apparently slower during work in the far range. Latency of accommodation is unaffected by working range. This new dynamic range nonlinearity has been defined in connection with a continuing research study of accommodation responses in normal subjects and in clinic patients. Instrumentation and analysis procedures are described.

ISSN:0093-7002    

出版商:OVID    

年代:1978

数据来源: OVID

摘要:

Fuchs's endothelial dystrophy interferes with removal of fluid from the cornea by the endothelium. It progresses through stages of corneal guttata, corneal edema, bullous keratopathy, vascularization, and scarring, and complications such as glaucoma or infection. The optometrist can detect this disorder and manage its early stages as well as provide counseling and proper referral. This paper includes a case study and a discussion of the course and treatment of this disease.

ISSN:0093-7002    

出版商:OVID    

年代:1978

数据来源: OVID

摘要:

When a subject monocularly views a bar grating that is oriented counterclockwise from vertical, and then immediately looks at a vertically oriented grating, he/she perceives it rotated clockwise. This tilt aftereffect occurs when the adapting and test targets are viewed by the same eye (direct effect) or opposite eye (interocular transferral effect). An apparatus has been developed to measure the tilt aftereffect in a clinical setting and to use such measures in assessing the prognosis for functional correction of strabismus on the assumption that the transferred tilt aftereffect is an indicator of the percentage of binocularly driven cortical neurons. Results from six normal and two strabismic subjects are presented.

ISSN:0093-7002    

出版商:OVID    

年代:1978

数据来源: OVID

摘要:

The ophthalmic literature dealing with diseases of the optic nerve, tracts, and visual cortex was reviewed for the period November 19761 to November 1977. Thirty-three papers of interest to optometrists have been abstracted. Main areas of interest include response of posterior segment to anterior-segment disturbances; structural anomalies in nerve-head region, including a new potential cause for hypoplasia of optic nerve; speculation on possible common origins of; RPE/Bruch's membrane disturbances and endothelium/Descemet's membrane disturbances; a vascular hypothesis for pathogenesis of optic-nerve-head drusen; an explanation for reversibility of infantile glaucomatous cupping; glaucomatocyclitic crisis; the role of axoplasmic flow in papilledema; new developments in field testing for early glaucomatous loss; effects of cerebral vascular accidents on color vision; and two interesting instances of systemic disease with ocular manifestations.

ISSN:0093-7002    

出版商:OVID    

年代:1978

数据来源: OVID