Method of measuring and mapping the scope of vision, from central to peripheral of each eye.
The total area or space visible in a person's peripheral vision with the eye looking straightforward.
A localized defect in the visual field bordered by an area of normal vision. This occurs with a variety of EYE DISEASES (e.g., RETINAL DISEASES and GLAUCOMA); OPTIC NERVE DISEASES, and other conditions.
Visual impairments limiting one or more of the basic functions of the eye: visual acuity, dark adaptation, color vision, or peripheral vision. These may result from EYE DISEASES; OPTIC NERVE DISEASES; VISUAL PATHWAY diseases; OCCIPITAL LOBE diseases; OCULAR MOTILITY DISORDERS; and other conditions (From Newell, Ophthalmology: Principles and Concepts, 7th ed, p132).
A series of tests used to assess various functions of the eyes.
Instruments used to observe distant objects.
An ocular disease, occurring in many forms, having as its primary characteristics an unstable or a sustained increase in the intraocular pressure which the eye cannot withstand without damage to its structure or impairment of its function. The consequences of the increased pressure may be manifested in a variety of symptoms, depending upon type and severity, such as excavation of the optic disk, hardness of the eyeball, corneal anesthesia, reduced visual acuity, seeing of colored halos around lights, disturbed dark adaptation, visual field defects, and headaches. (Dictionary of Visual Science, 4th ed)
Partial or complete loss of vision in one half of the visual field(s) of one or both eyes. Subtypes include altitudinal hemianopsia, characterized by a visual defect above or below the horizontal meridian of the visual field. Homonymous hemianopsia refers to a visual defect that affects both eyes equally, and occurs either to the left or right of the midline of the visual field. Binasal hemianopsia consists of loss of vision in the nasal hemifields of both eyes. Bitemporal hemianopsia is the bilateral loss of vision in the temporal fields. Quadrantanopsia refers to loss of vision in one quarter of the visual field in one or both eyes.
Clarity or sharpness of OCULAR VISION or the ability of the eye to see fine details. Visual acuity depends on the functions of RETINA, neuronal transmission, and the interpretative ability of the brain. Normal visual acuity is expressed as 20/20 indicating that one can see at 20 feet what should normally be seen at that distance. Visual acuity can also be influenced by brightness, color, and contrast.
Glaucoma in which the angle of the anterior chamber is open and the trabecular meshwork does not encroach on the base of the iris.
A condition in which the intraocular pressure is elevated above normal and which may lead to glaucoma.
Conditions which produce injury or dysfunction of the second cranial or optic nerve, which is generally considered a component of the central nervous system. Damage to optic nerve fibers may occur at or near their origin in the retina, at the optic disk, or in the nerve, optic chiasm, optic tract, or lateral geniculate nuclei. Clinical manifestations may include decreased visual acuity and contrast sensitivity, impaired color vision, and an afferent pupillary defect.
Area of the OCCIPITAL LOBE concerned with the processing of visual information relayed via VISUAL PATHWAYS.
The selecting and organizing of visual stimuli based on the individual's past experience.
The electric response evoked in the cerebral cortex by visual stimulation or stimulation of the visual pathways.
The pressure of the fluids in the eye.
The minimum amount of stimulus energy necessary to elicit a sensory response.
Set of cell bodies and nerve fibers conducting impulses from the eyes to the cerebral cortex. It includes the RETINA; OPTIC NERVE; optic tract; and geniculocalcarine tract.
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
Investigative technique commonly used during ELECTROENCEPHALOGRAPHY in which a series of bright light flashes or visual patterns are used to elicit brain activity.
The tendency to explore or investigate a novel environment. It is considered a motivation not clearly distinguishable from curiosity.
Mental process to visually perceive a critical number of facts (the pattern), such as characters, shapes, displays, or designs.
The observable response an animal makes to any situation.
The process in which light signals are transformed by the PHOTORECEPTOR CELLS into electrical signals which can then be transmitted to the brain.
The portion of the optic nerve seen in the fundus with the ophthalmoscope. It is formed by the meeting of all the retinal ganglion cell axons as they enter the optic nerve.
The ability to detect sharp boundaries (stimuli) and to detect slight changes in luminance at regions without distinct contours. Psychophysical measurements of this visual function are used to evaluate visual acuity and to detect eye disease.
The physical activity of a human or an animal as a behavioral phenomenon.
Learning the correct route through a maze to obtain reinforcement. It is used for human or animal populations. (Thesaurus of Psychological Index Terms, 6th ed)
Games in which players use a racquet to hit a ball or similar type object.
The positioning and accommodation of eyes that allows the image to be brought into place on the FOVEA CENTRALIS of each eye.
The blending of separate images seen by each eye into one composite image.
The real or apparent movement of objects through the visual field.
Focusing on certain aspects of current experience to the exclusion of others. It is the act of heeding or taking notice or concentrating.
Voluntary or reflex-controlled movements of the eye.
The awareness of the spatial properties of objects; includes physical space.
The X-shaped structure formed by the meeting of the two optic nerves. At the optic chiasm the fibers from the medial part of each retina cross to project to the other side of the brain while the lateral retinal fibers continue on the same side. As a result each half of the brain receives information about the contralateral visual field from both eyes.
An analogue of GAMMA-AMINOBUTYRIC ACID. It is an irreversible inhibitor of 4-AMINOBUTYRATE TRANSAMINASE, the enzyme responsible for the catabolism of GAMMA-AMINOBUTYRIC ACID. (From Martindale The Extra Pharmacopoeia, 31st ed)
The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.
The science dealing with the correlation of the physical characteristics of a stimulus, e.g., frequency or intensity, with the response to the stimulus, in order to assess the psychologic factors involved in the relationship.
Recording of electric potentials in the retina after stimulation by light.
The time from the onset of a stimulus until a response is observed.
Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.
Neurons of the innermost layer of the retina, the internal plexiform layer. They are of variable sizes and shapes, and their axons project via the OPTIC NERVE to the brain. A small subset of these cells act as photoreceptors with projections to the SUPRACHIASMATIC NUCLEUS, the center for regulating CIRCADIAN RHYTHM.
The inability to see or the loss or absence of perception of visual stimuli. This condition may be the result of EYE DISEASES; OPTIC NERVE DISEASES; OPTIC CHIASM diseases; or BRAIN DISEASES affecting the VISUAL PATHWAYS or OCCIPITAL LOBE.
Feeling or emotion of dread, apprehension, and impending disaster but not disabling as with ANXIETY DISORDERS.
An imaging method using LASERS that is used for mapping subsurface structure. When a reflective site in the sample is at the same optical path length (coherence) as the reference mirror, the detector observes interference fringes.
Methods and procedures for the diagnosis of diseases of the eye or of vision disorders.
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
Images seen by one eye.
An area approximately 1.5 millimeters in diameter within the macula lutea where the retina thins out greatly because of the oblique shifting of all layers except the pigment epithelium layer. It includes the sloping walls of the fovea (clivus) and contains a few rods in its periphery. In its center (foveola) are the cones most adapted to yield high visual acuity, each cone being connected to only one ganglion cell. (Cline et al., Dictionary of Visual Science, 4th ed)
Hereditary, progressive degeneration of the neuroepithelium of the retina characterized by night blindness and progressive contraction of the visual field.
A response to a cue that is instrumental in avoiding a noxious experience.
Agents destructive to snails and other mollusks.
An activity in which the body is propelled through water by specific movement of the arms and/or the legs. Swimming as propulsion through water by the movement of limbs, tail, or fins of animals is often studied as a form of PHYSICAL EXERTION or endurance.
Behavioral manifestations of cerebral dominance in which there is preferential use and superior functioning of either the left or the right side, as in the preferred use of the right hand or right foot.
Slender processes of NEURONS, including the AXONS and their glial envelopes (MYELIN SHEATH). Nerve fibers conduct nerve impulses to and from the CENTRAL NERVOUS SYSTEM.
A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.
Fields representing the joint interplay of electric and magnetic forces.
Vision considered to be inferior to normal vision as represented by accepted standards of acuity, field of vision, or motility. Low vision generally refers to visual disorders that are caused by diseases that cannot be corrected by refraction (e.g., MACULAR DEGENERATION; RETINITIS PIGMENTOSA; DIABETIC RETINOPATHY, etc.).
Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.
Ischemic injury to the OPTIC NERVE which usually affects the OPTIC DISK (optic neuropathy, anterior ischemic) and less frequently the retrobulbar portion of the nerve (optic neuropathy, posterior ischemic). The injury results from occlusion of arterial blood supply which may result from TEMPORAL ARTERITIS; ATHEROSCLEROSIS; COLLAGEN DISEASES; EMBOLISM; DIABETES MELLITUS; and other conditions. The disease primarily occurs in the sixth decade or later and presents with the sudden onset of painless and usually severe monocular visual loss. Anterior ischemic optic neuropathy also features optic disk edema with microhemorrhages. The optic disk appears normal in posterior ischemic optic neuropathy. (Glaser, Neuro-Ophthalmology, 2nd ed, p135)
An abrupt voluntary shift in ocular fixation from one point to another, as occurs in reading.
Elements of limited time intervals, contributing to particular results or situations.
The coordination of a sensory or ideational (cognitive) process and a motor activity.
Agents that alleviate ANXIETY, tension, and ANXIETY DISORDERS, promote sedation, and have a calming effect without affecting clarity of consciousness or neurologic conditions. ADRENERGIC BETA-ANTAGONISTS are commonly used in the symptomatic treatment of anxiety but are not included here.
Examination of the interior of the eye with an ophthalmoscope.
Differential response to different stimuli.
Measurement of ocular tension (INTRAOCULAR PRESSURE) with a tonometer. (Cline, et al., Dictionary of Visual Science, 4th ed)
The oxygen consumption level above which aerobic energy production is supplemented by anaerobic mechanisms during exercise, resulting in a sustained increase in lactate concentration and metabolic acidosis. The anaerobic threshold is affected by factors that modify oxygen delivery to the tissues; it is low in patients with heart disease. Methods of measurement include direct measure of lactate concentration, direct measurement of bicarbonate concentration, and gas exchange measurements.
Processes and properties of the EYE as a whole or of any of its parts.
Cognitive disorders characterized by an impaired ability to perceive the nature of objects or concepts through use of the sense organs. These include spatial neglect syndromes, where an individual does not attend to visual, auditory, or sensory stimuli presented from one side of the body.
A form of GLAUCOMA in which chronic optic nerve damage and loss of vision normally attributable to buildup of intraocular pressure occurs despite prevailing conditions of normal intraocular pressure.
Retinal diseases refer to medical conditions that affect the retina, the light-sensitive tissue at the back of the eye, leading to vision loss or blindness.
The sensory discrimination of a pattern shape or outline.
Posterior portion of the CEREBRAL HEMISPHERES responsible for processing visual sensory information. It is located posterior to the parieto-occipital sulcus and extends to the preoccipital notch.
Signals for an action; that specific portion of a perceptual field or pattern of stimuli to which a subject has learned to respond.
The aperture in the iris through which light passes.
A pair of ophthalmic lenses in a frame or mounting which is supported by the nose and ears. The purpose is to aid or improve vision. It does not include goggles or nonprescription sun glasses for which EYE PROTECTIVE DEVICES is available.
The concave interior of the eye, consisting of the retina, the choroid, the sclera, the optic disk, and blood vessels, seen by means of the ophthalmoscope. (Cline et al., Dictionary of Visual Science, 4th ed)
The anterior pair of the quadrigeminal bodies which coordinate the general behavioral orienting responses to visual stimuli, such as whole-body turning, and reaching.
Total loss of vision in all or part of the visual field due to bilateral OCCIPITAL LOBE (i.e., VISUAL CORTEX) damage or dysfunction. Anton syndrome is characterized by the psychic denial of true, organic cortical blindness. (Adams et al., Principles of Neurology, 6th ed, p460)
Awareness of oneself in relation to time, place and person.
Visualization of a vascular system after intravenous injection of a fluorescein solution. The images may be photographed or televised. It is used especially in studying the retinal and uveal vasculature.
Upper central part of the cerebral hemisphere. It is located posterior to central sulcus, anterior to the OCCIPITAL LOBE, and superior to the TEMPORAL LOBES.
Method of making images on a sensitized surface by exposure to light or other radiant energy.
The 2nd cranial nerve which conveys visual information from the RETINA to the brain. The nerve carries the axons of the RETINAL GANGLION CELLS which sort at the OPTIC CHIASM and continue via the OPTIC TRACTS to the brain. The largest projection is to the lateral geniculate nuclei; other targets include the SUPERIOR COLLICULI and the SUPRACHIASMATIC NUCLEI. Though known as the second cranial nerve, it is considered part of the CENTRAL NERVOUS SYSTEM.
Part of the DIENCEPHALON inferior to the caudal end of the dorsal THALAMUS. Includes the lateral geniculate body which relays visual impulses from the OPTIC TRACT to the calcarine cortex, and the medial geniculate body which relays auditory impulses from the lateral lemniscus to the AUDITORY CORTEX.
Imaging methods that result in sharp images of objects located on a chosen plane and blurred images located above or below the plane.
The point or frequency at which all flicker of an intermittent light stimulus disappears.
A species of the genus MACACA inhabiting India, China, and other parts of Asia. The species is used extensively in biomedical research and adapts very well to living with humans.
The active insecticidal constituent of CHRYSANTHEMUM CINERARIIFOLIUM flowers. Pyrethrin I is the pyretholone ester of chrysanthemummonocarboxylic acid and pyrethrin II is the pyretholone ester of chrysanthemumdicarboxylic acid monomethyl ester.
Persons with loss of vision such that there is an impact on activities of daily living.
Theoretical representations that simulate the behavior or activity of the neurological system, processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
Relatively bright light, or the dazzling sensation of relatively bright light, which produces unpleasantness or discomfort, or which interferes with optimal VISION, OCULAR. (Cline et al., Dictionary of Visual Science, 4th ed)
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
Swelling of the OPTIC DISK, usually in association with increased intracranial pressure, characterized by hyperemia, blurring of the disk margins, microhemorrhages, blind spot enlargement, and engorgement of retinal veins. Chronic papilledema may cause OPTIC ATROPHY and visual loss. (Miller et al., Clinical Neuro-Ophthalmology, 4th ed, p175)
Areas of attractive or repulsive force surrounding MAGNETS.
Deviations from the average or standard indices of refraction of the eye through its dioptric or refractive apparatus.
The absence or restriction of the usual external sensory stimuli to which the individual responds.
The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)
Adjustment of the eyes under conditions of low light. The sensitivity of the eye to light is increased during dark adaptation.
Inflammation of the optic nerve. Commonly associated conditions include autoimmune disorders such as MULTIPLE SCLEROSIS, infections, and granulomatous diseases. Clinical features include retro-orbital pain that is aggravated by eye movement, loss of color vision, and contrast sensitivity that may progress to severe visual loss, an afferent pupillary defect (Marcus-Gunn pupil), and in some instances optic disc hyperemia and swelling. Inflammation may occur in the portion of the nerve within the globe (neuropapillitis or anterior optic neuritis) or the portion behind the globe (retrobulbar neuritis or posterior optic neuritis).
A nonspecific term referring to impaired vision. Major subcategories include stimulus deprivation-induced amblyopia and toxic amblyopia. Stimulus deprivation-induced amblyopia is a developmental disorder of the visual cortex. A discrepancy between visual information received by the visual cortex from each eye results in abnormal cortical development. STRABISMUS and REFRACTIVE ERRORS may cause this condition. Toxic amblyopia is a disorder of the OPTIC NERVE which is associated with ALCOHOLISM, tobacco SMOKING, and other toxins and as an adverse effect of the use of some medications.
Defects of color vision are mainly hereditary traits but can be secondary to acquired or developmental abnormalities in the CONES (RETINA). Severity of hereditary defects of color vision depends on the degree of mutation of the ROD OPSINS genes (on X CHROMOSOME and CHROMOSOME 3) that code the photopigments for red, green and blue.
Pesticides designed to control insects that are harmful to man. The insects may be directly harmful, as those acting as disease vectors, or indirectly harmful, as destroyers of crops, food products, or textile fabrics.
An activity in which the body is propelled by moving the legs rapidly. Running is performed at a moderate to rapid pace and should be differentiated from JOGGING, which is performed at a much slower pace.
The effect of environmental or physiological factors on the driver and driving ability. Included are driving fatigue, and the effect of drugs, disease, and physical disabilities on driving.
Function of the human eye that is used in bright illumination or in daylight (at photopic intensities). Photopic vision is performed by the three types of RETINAL CONE PHOTORECEPTORS with varied peak absorption wavelengths in the color spectrum (from violet to red, 400 - 700 nm).
Conditions which affect the structure or function of the pupil of the eye, including disorders of innervation to the pupillary constrictor or dilator muscles, and disorders of pupillary reflexes.
The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.
Mental processing of chromatic signals (COLOR VISION) from the eye by the VISUAL CORTEX where they are converted into symbolic representations. Color perception involves numerous neurons, and is influenced not only by the distribution of wavelengths from the viewed object, but also by its background color and brightness contrast at its boundary.
Complex mental function having four distinct phases: (1) memorizing or learning, (2) retention, (3) recall, and (4) recognition. Clinically, it is usually subdivided into immediate, recent, and remote memory.
The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.
The worsening of a disease over time. This concept is most often used for chronic and incurable diseases where the stage of the disease is an important determinant of therapy and prognosis.
An oval area in the retina, 3 to 5 mm in diameter, usually located temporal to the posterior pole of the eye and slightly below the level of the optic disk. It is characterized by the presence of a yellow pigment diffusely permeating the inner layers, contains the fovea centralis in its center, and provides the best phototropic visual acuity. It is devoid of retinal blood vessels, except in its periphery, and receives nourishment from the choriocapillaris of the choroid. (From Cline et al., Dictionary of Visual Science, 4th ed)
A technique of inputting two-dimensional images into a computer and then enhancing or analyzing the imagery into a form that is more useful to the human observer.
Perception of three-dimensionality.
The adjustment of the eye to variations in the intensity of light. Light adaptation is the adjustment of the eye when the light threshold is increased; DARK ADAPTATION when the light is greatly reduced. (From Cline et al., Dictionary of Visual Science, 4th ed)
Misalignment of the visual axes of the eyes. In comitant strabismus the degree of ocular misalignment does not vary with the direction of gaze. In noncomitant strabismus the degree of misalignment varies depending on direction of gaze or which eye is fixating on the target. (Miller, Walsh & Hoyt's Clinical Neuro-Ophthalmology, 4th ed, p641)
An adrenocortical steroid that has modest but significant activities as a mineralocorticoid and a glucocorticoid. (From Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed, p1437)
The ability to respond to segments of the perceptual experience rather than to the whole.
Dominance of one cerebral hemisphere over the other in cerebral functions.
A form of glaucoma in which the intraocular pressure increases because the angle of the anterior chamber is blocked and the aqueous humor cannot drain from the anterior chamber.
A genus of the subfamily CERCOPITHECINAE, family CERCOPITHECIDAE, consisting of 16 species inhabiting forests of Africa, Asia, and the islands of Borneo, Philippines, and Celebes.
Atrophy of the optic disk which may be congenital or acquired. This condition indicates a deficiency in the number of nerve fibers which arise in the RETINA and converge to form the OPTIC DISK; OPTIC NERVE; OPTIC CHIASM; and optic tracts. GLAUCOMA; ISCHEMIA; inflammation, a chronic elevation of intracranial pressure, toxins, optic nerve compression, and inherited conditions (see OPTIC ATROPHIES, HEREDITARY) are relatively common causes of this condition.
Any surgical procedure for treatment of glaucoma by means of puncture or reshaping of the trabecular meshwork. It includes goniotomy, trabeculectomy, and laser perforation.
An illusion of vision usually affecting spatial relations.
The sensory interpretation of the dimensions of objects.
Diseases affecting the eye.
Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.
A subjective visual sensation with the eyes closed and in the absence of light. Phosphenes can be spontaneous, or induced by chemical, electrical, or mechanical (pressure) stimuli which cause the visual field to light up without optical inputs.
Photosensitive afferent neurons located primarily within the FOVEA CENTRALIS of the MACULA LUTEA. There are three major types of cone cells (red, blue, and green) whose photopigments have different spectral sensitivity curves. Retinal cone cells operate in daylight vision (at photopic intensities) providing color recognition and central visual acuity.
The act of knowing or the recognition of a distance by recollective thought, or by means of a sensory process which is under the influence of set and of prior experience.

Test-retest variability of frequency-doubling perimetry and conventional perimetry in glaucoma patients and normal subjects. (1/1026)

PURPOSE: To compare the test-retest variability characteristics of frequency-doubling perimetry, a new perimetric test, with those of conventional perimetry in glaucoma patients and normal control subjects. METHODS: The study sample contained 64 patients and 47 normal subjects aged 66.16+/-11.86 and 64.26+/-7.99 years (mean +/- SD), respectively. All subjects underwent frequency-doubling perimetry (using the threshold mode) and conventional perimetry (using program 30-2 of the Humphrey Field Analyzer; Humphrey Instruments, San Leandro, CA) in one randomly selected eye. Each test was repeated at 1-week intervals for five tests with each technique over 4 weeks. Empirical 5th and 95th percentiles of the distribution of threshold deviations at retest were determined for all combinations of single tests and mean of two tests, stratified by threshold deviation. The influence of visual field eccentricity and overall visual field loss on variability also were examined. RESULTS: Mean test time with frequency-doubling perimetry in patients and normal control subjects was 5.90 and 5.25 minutes, respectively, and with conventional perimetry was 17.20 and 14.01 minutes, respectively. In patients, there was a significant correlation between the results of the two techniques, in the full field and in quadrants, whereas in normal subjects there was no such correlation. In patients, the retest variability of conventional perimetry in locations with 20-dB loss was 120% (single tests) and 127% (mean tests) higher compared with that in locations with 0-dB loss. Comparative figures for frequency-doubling perimetry were 40% and 47%, respectively. Variability also increased more with threshold deviation in normal subjects tested with conventional perimetry. In both patients and normal subjects, variability increased with visual field eccentricity in conventional perimetry, but not in frequency-doubling perimetry. Both techniques showed an increase in variability with overall visual field damage. CONCLUSIONS: Frequency-doubling perimetry has different test-retest variability characteristics than conventional perimetry and may have potential for monitoring glaucomatous field damage.  (+info)

Between-algorithm, between-individual differences in normal perimetric sensitivity: full threshold, FASTPAC, and SITA. Swedish Interactive Threshold algorithm. (2/1026)

PURPOSE: To determine the between-algorithm differences in perimetric sensitivity for the Swedish Interactive Threshold algorithm (SITA) Standard, SITA Fast, FASTPAC, and Full Threshold algorithms; to determine the between-subject, between-algorithm differences in the magnitude of the normal variation in sensitivity. METHODS: The sample comprised 50 normal subjects (mean age, 52.9 +/- 18.5 years) experienced in automated perimetry. One randomly assigned eye was examined at three visits with Program 30-2 of the Humphrey Field Analyzer (HFA). The first visit was a familiarization session. A two-period crossover design with order randomization within visits was used over the second and third visits. SITA Standard, SITA Fast, and HFA 640 Full Threshold were administered during one visit. FASTPAC and HFA 750 Full Threshold were administered during the remaining visit. RESULTS: Group mean Mean Sensitivity was 0.8 dB higher for SITA Standard than for Full Threshold (P < 0.001) and 1.3 dB higher for SITA Fast than for Full Threshold (P < 0.001). A similar trend was found between SITA and FASTPAC. The group mean Mean Sensitivity for SITA Fast was 0.5 dB higher than for SITA Standard (P < 0.001). The pointwise between-algorithm difference in sensitivity was similar for all algorithms. The pointwise between-algorithm, between-subject variability was lower for SITA. The examination durations for SITA Fast and SITA Standard were half those for FASTPAC and Full Threshold; SITA Fast was 41% that of SITA Standard (P < 0.001). CONCLUSIONS: SITA produced marginally higher mean mean sensitivity compared with that of existing algorithms and markedly reduced examination duration. The reduced between-subject variability of SITA should result in narrower confidence limits for definition of normality.  (+info)

Looking behind a pathological blind spot in human retina. (3/1026)

Recent work suggests that dichoptic lateral interactions occur in the region of the visual field of one eye that corresponds to the physiological blind spot in the other eye (Tripathy, S. P., & Levi, D. M. (1994). The two-dimensional shape of spatial interaction zones in the parafovea. Vision Research, 34, 1127-1138.) Here we ask whether dichoptic lateral interactions occur in the region of the visual field of one eye that corresponds to a pathological blind spot, a retinal coloboma in the other eye. To address this question we had the observer report the orientation of a letter 'T' presented within this region in the presence of flanking 'T's presented to the other eye around the coloboma. A large drop in performance was seen due to the flanks, showing the existence of dichoptic lateral interactions in this monocular region. The presence of these dichoptic interactions in a region lacking direct retinal afferents from one eye is consistent with the proposition that long-range horizontal connections of the primary visual cortex mediate these interactions.  (+info)

Does visual sensitivity improve between 5 and 8 years? A study of automated visual field examination. (4/1026)

In 74 normal subjects (62 children aged 5-8 years and 12 adults), we tested the widely-held belief that visual sensitivity improves substantially during childhood. Maturation of the retino-striate pathways is generally invoked to account for age-related changes in visual sensitivity. We evaluated the extent to which attentional factors unduly emphasized the effect of age on the purely physiological mechanisms. After a specially-designed familiarization procedure, sensitivity was fully evaluated at two locations in the superior temporal field using a bracketing technique (Octopus 2000R). False-positive (FP) and false-negative (FN) catch-trials were interspersed with the sequence of stimuli. Analyses demonstrated that: (1) age affected sensitivity; and (2) the general level of attentiveness varied not only with age, but also among subjects in the same age group. We then estimated the extent to which improved visual sensitivity may reflect a concomitant evolution of vigilance. Firstly, controlled variance analyses indicated that factors for evaluating attentiveness (rate of FN responses, slope of the psychometric function at the median, and goodness of fit) were indeed much better predictors than age of the sensitivity measured. Secondly and more significantly, the grouping of subjects into homogeneous subgroups, on the basis of their attentional performance, showed that children as young as 5 years may have a visual sensitivity that is only marginally lower than that of adults.  (+info)

Models for the description of angioscotomas. (5/1026)

To describe small scotomas in visual field examinations several statistical models are proposed and applied to the evaluation of angioscotoma in 13 ophthalmologically normal subjects. A special perimetric grid is used where thresholds can be estimated along a line of narrow-spaced test points which crosses the predicted location of the retinal vessel. A two-stage analysis employs single estimations to fit a threshold curve by means of a special parametric description of the luminance difference sensitivity threshold as a function of stimulus position. An alternative model incorporates the threshold as a function of position into the probabilistic description of the binary response (stimulus seen/not seen).  (+info)

Angioscotoma detection with fundus-oriented perimetry. A study with dark and bright stimuli of different sizes. (6/1026)

Fundus-oriented perimetry (FOP) was used to evaluate the effectiveness of different-sized bright and dark stimuli in detecting and quantitatively measuring angioscotoma. The foveolas and optic disks of digitized fundus images were aligned with their psychophysical counterparts to construct individual grids of perimetric stimuli. Each grid included a linear set of test point locations crossing a retinal vessel. Angioscotomas immediately became visible in nine of 13 healthy normal volunteers tested with FOP. Additional mathematical processing of local loss of differential light sensitivity (dls) disclosed an angioscotoma for at least one stimulus condition in all persons tested. The angioscomas were usually deeper for small (12) targets than for large (32') ones. On the other hand, the overall noise at dls thresholds was generally higher for small than for large stimuli regardless of whether the stimuli were bright or dark. No noteworthy differences were found in detection rates or signal-to-noise ratios under different stimulus conditions (dark/bright/small/large). FOP permits the individual arrangement of stimuli for specific morphological conditions and is thus capable of detecting even minute visual field defects such as angioscotomas.  (+info)

Preperimetric glaucoma diagnosis by confocal scanning laser tomography of the optic disc. (7/1026)

AIM: To evaluate the ability of confocal scanning laser tomography of the optic nerve head to detect glaucomatous optic nerve damage in ocular hypertensive eyes without visual field defects. METHODS: The study included 50 normal subjects, 61 glaucoma patients with glaucomatous changes in the optic disc and visual field, and 102 "preperimetric" patients with increased intraocular pressure, normal visual fields, and glaucomatous appearance of the optic disc as evaluated on colour stereo optic disc photographs. For all individuals, confocal scanning laser tomographs of the optic nerve head were taken using the Heidelberg retina tomograph (HRT; software 2.01). RESULTS: Almost all investigated HRT variables varied significantly (p < 0.05) between the normal eyes and preperimetric glaucoma eyes with pronounced overlap between the two study groups. Corresponding to the overlap, sensitivity and specificity values were relatively low when HRT variables were taken to differentiate between normal and preperimetric glaucoma eyes. At a given specificity of 95% highest sensitivities were found for the variables "rim area in the superior disc sector" (24.8%), "nerve fibre layer thickness in the inferior disc sector" (26.5%), and "rim volume in the superior disc sector" (25.5%). A multivariate approach increased sensitivity to 42.2% at a given specificity of 95%. For the glaucoma group highest sensitivity values were reached by rim volume in the superior disc sector (73.8%) and rim area (72.1%); the multivariate approach reached 83.6%. CONCLUSIONS: Owing to pronounced overlapping between the groups, confocal scanning laser tomography of the optic nerve head has relatively low diagnostic power to differentiate between normal eyes and preperimetric glaucoma eyes. One of the reasons may be the biological interindividual variability of quantitative optic disc variables.  (+info)

Measurement of retinal nerve fibre layer by scanning laser polarimetry and high pass resolution perimetry in normal tension glaucoma with relatively high or low intraocular pressure. (8/1026)

AIMS: To determine whether any differences may exist in the relation between the neural capacity as determined by high pass resolution perimetry and the thickness of the retinal nerve fibre layer (RNFL) in patients having normal tension glaucoma (NTG) with a relatively high intraocular pressure (IOP) between 16 and 21 mm Hg (HNTG) v those with a lower IOP below 15 mm Hg (LNTG). METHODS: Scanning laser polarimetry and high pass resolution perimetry were performed in 20 eyes of 20 patients with HNTG and 21 eyes of 21 patients with LNTG. The correlation between total and regional thickness of the peripapillary RNFL and the corresponding total and regional neural capacity with linear regression analysis were evaluated. RESULTS: Overall, although the total RNFL thickness was not significantly correlated with the total neural capacity, the RNFL thickness in each of the superior and inferior quadrants was significantly correlated with the corresponding regional neural capacity (r = 0.44, p = 0.0045; r = 0.39, p = 0.0126 for each). The RNFL thickness in each of the superior and inferior quadrants in the HNTG group was significantly correlated with the corresponding regional neural capacity (r = 0.52, p = 0.0196; r = 0.49, p = 0.0286 for each). No significant correlation between neural capacity and the RNFL thickness was observed either globally or regionally in the LNTG group. CONCLUSION: The degree of the correlation between neural capacity as determined by high pass resolution perimetry and thickness of the RNFL as measured by scanning laser polarimetry appeared to differ in NTG patients with an IOP higher than 15 mm Hg v those with a lower IOP.  (+info)

In the medical field, a scotoma refers to a visual field defect or loss of vision in a specific area of the visual field. It is typically caused by damage to the retina, optic nerve, or other structures in the eye that are responsible for transmitting visual information to the brain. Scotomas can be classified as central or peripheral, depending on the location of the visual field loss. Central scotomas involve a loss of vision in the center of the visual field, while peripheral scotomas involve a loss of vision in the outer edges of the visual field. Scotomas can be caused by a variety of conditions, including glaucoma, diabetic retinopathy, macular degeneration, and optic neuritis. Treatment for scotomas depends on the underlying cause and may include medications, surgery, or other interventions to slow or stop the progression of the underlying condition.

Vision disorders refer to a range of conditions that affect an individual's ability to see clearly or perceive visual information accurately. These disorders can affect any part of the visual system, including the eyes, the optic nerve, the brain, or the visual pathways that connect these structures. Some common vision disorders include: 1. Refractive errors: These are errors in the shape of the eye that cause light to focus incorrectly on the retina, leading to blurred vision. Examples include nearsightedness (myopia), farsightedness (hyperopia), and astigmatism. 2. Cataracts: A cataract is a clouding of the lens in the eye that can cause。 3. Glaucoma: Glaucoma is a group of eye diseases that can damage the optic nerve and lead to vision loss or blindness. 4. Age-related macular degeneration (AMD): AMD is a progressive eye disease that affects the macula, the part of the retina responsible for central vision. 5. Diabetic retinopathy: This is a complication of diabetes that can cause damage to the blood vessels in the retina, leading to vision loss. 6. Retinitis pigmentosa: This is a genetic disorder that causes progressive damage to the retina, leading to night blindness and eventually vision loss. 7. Amblyopia: Amblyopia, also known as lazy eye, is a condition in which the brain does not properly use one eye, leading to reduced vision in that eye. These are just a few examples of the many vision disorders that can affect individuals. Treatment for these disorders may include corrective lenses, surgery, medication, or other interventions, depending on the specific condition and its severity.

Glaucoma is a group of eye diseases that damage the optic nerve, which is responsible for transmitting visual information from the eye to the brain. This damage can lead to gradual vision loss and, in severe cases, blindness. There are several types of glaucoma, including open-angle glaucoma, closed-angle glaucoma, and normal-tension glaucoma. Open-angle glaucoma is the most common type and typically affects both eyes. It occurs when the drainage system in the eye becomes blocked, causing increased pressure inside the eye. Closed-angle glaucoma is less common and occurs when the iris blocks the drainage system, causing a sudden increase in eye pressure. Normal-tension glaucoma occurs when the eye pressure is within the normal range, but the optic nerve is still damaged. Symptoms of glaucoma may include blurred vision, eye pain, redness, and sensitivity to light. However, many people with glaucoma have no symptoms until the disease is advanced. That's why regular eye exams are important for early detection and treatment. Treatment for glaucoma typically involves lowering eye pressure with medication, laser therapy, or surgery. The goal of treatment is to slow or stop the progression of the disease and preserve vision.

Hemianopsia is a neurological condition characterized by a partial loss of vision in one half of the visual field, resulting in a "split vision" or "blind spot" on one side. It can be caused by damage to the optic nerve, which carries visual information from the eye to the brain, or to the brain itself. Hemianopsia can be classified as either homonymous (when both eyes are affected on the same side) or heteronymous (when the two eyes are affected on opposite sides). It can be a symptom of a variety of neurological disorders, including stroke, brain tumors, and multiple sclerosis. Treatment for hemianopsia depends on the underlying cause and may include medications, surgery, or rehabilitation therapy.

Glaucoma, open-angle, is a type of glaucoma that occurs when the drainage system in the eye becomes blocked or damaged, leading to an increase in pressure within the eye. This increased pressure can damage the optic nerve, which can result in vision loss or blindness if left untreated. In open-angle glaucoma, the drainage system of the eye is not completely blocked, but rather the angle between the iris and the cornea becomes narrower, reducing the amount of fluid that can drain out of the eye. This can cause the pressure within the eye to gradually increase over time, leading to damage to the optic nerve. Open-angle glaucoma is the most common type of glaucoma and is often referred to as "the sneak thief of sight" because it typically progresses slowly and without noticeable symptoms in the early stages. However, if left untreated, it can cause significant vision loss or blindness. Treatment for open-angle glaucoma typically involves medications to lower the pressure within the eye, laser surgery, or surgery to improve the drainage of fluid from the eye.

Ocular hypertension is a condition characterized by elevated intraocular pressure (IOP) within the eye, which is above the normal range of 10-21 mmHg. The elevated IOP can cause damage to the optic nerve, leading to vision loss or even blindness if left untreated. Ocular hypertension is often asymptomatic, meaning that individuals with the condition may not experience any noticeable symptoms. However, it is considered a risk factor for the development of glaucoma, a progressive eye disease that can cause irreversible vision loss. Diagnosis of ocular hypertension typically involves measuring the IOP using a tonometer, a device that measures the pressure within the eye. If the IOP is consistently above 21 mmHg, the individual may be diagnosed with ocular hypertension. Treatment for ocular hypertension typically involves medications to lower the IOP, such as eye drops or oral medications. In some cases, laser surgery or other procedures may be recommended to reduce the pressure within the eye. Regular monitoring of the IOP is also important to ensure that the condition is being effectively managed and to detect any potential complications.

Optic nerve diseases refer to a group of medical conditions that affect the optic nerve, which is the nerve responsible for transmitting visual information from the retina to the brain. These diseases can cause a range of symptoms, including vision loss, eye pain, and changes in visual perception. Some common optic nerve diseases include: 1. Glaucoma: A group of eye diseases that damage the optic nerve, often caused by elevated pressure inside the eye. 2. Optic neuritis: Inflammation of the optic nerve that can cause vision loss, eye pain, and sensitivity to light. 3. Optic atrophy: A condition in which the optic nerve becomes thin and weak, leading to vision loss. 4. Leber's hereditary optic neuropathy: A genetic disorder that causes progressive vision loss, often starting in young adulthood. 5. Optic nerve drusen: Small deposits of calcium and other minerals that can form on the optic nerve, causing vision loss. 6. Optic nerve glioma: A type of brain tumor that can affect the optic nerve, causing vision loss and other symptoms. Treatment for optic nerve diseases depends on the specific condition and its severity. In some cases, medications or surgery may be used to manage symptoms or slow the progression of the disease. Early detection and treatment are important for preserving vision and preventing further damage to the optic nerve.

Vigabatrin is a medication that is primarily used to treat epilepsy, specifically in patients who have partial seizures that are not well-controlled by other medications. It works by inhibiting the enzyme gamma-aminobutyric acid (GABA) transaminase, which leads to an increase in the levels of the inhibitory neurotransmitter GABA in the brain. This increase in GABA activity can help to reduce the frequency and severity of seizures in people with epilepsy. Vigabatrin is usually taken orally and is typically prescribed at bedtime to help reduce the risk of side effects such as drowsiness. It is important to note that vigabatrin can cause vision problems, including loss of vision, and patients who take this medication should have regular eye exams.

Blindness is a medical condition characterized by a severe loss of vision that affects a person's ability to see and navigate their environment. In medical terms, blindness is defined as visual acuity of less than 20/200 in the better eye, even with corrective lenses. This means that a person with blindness cannot see as well as a person with normal vision, and may have difficulty recognizing faces, reading, or performing other tasks that require good vision. Blindness can be caused by a variety of factors, including genetic disorders, eye injuries, infections, diseases such as glaucoma or cataracts, and aging. It can also be caused by neurological conditions such as stroke or brain injury, or by certain medications or toxins. Treatment for blindness depends on the underlying cause and severity of the condition. In some cases, corrective lenses or surgery may be able to improve vision. In other cases, rehabilitation and assistive technology such as braille, audio books, and guide dogs may be necessary to help individuals with blindness live independently and participate fully in society.

Retinitis Pigmentosa (RP) is a group of inherited eye diseases that cause progressive damage to the retina, the light-sensitive layer at the back of the eye. RP is characterized by the accumulation of pigmented material in the retina, which leads to the death of photoreceptor cells, the specialized cells that detect light and send signals to the brain. As a result, people with RP experience progressive vision loss, typically starting with night blindness and gradually leading to tunnel vision and eventually complete blindness. RP can affect both eyes and is usually diagnosed in childhood or adolescence, although some forms of the disease may not be diagnosed until later in life. There is currently no cure for RP, but treatments such as low-vision aids and gene therapy are being studied as potential treatments.

In the medical field, "vision, low" refers to a visual acuity that is lower than normal. Visual acuity is a measure of how well a person can see at a specific distance, usually 20 feet (6 meters). A person with low vision may have difficulty seeing objects clearly, distinguishing between colors, or recognizing faces. This condition can be caused by a variety of factors, including eye diseases such as cataracts, glaucoma, or age-related macular degeneration, as well as neurological conditions such as stroke or brain injury. Low vision can affect a person's ability to perform daily activities, such as reading, driving, or recognizing faces. Treatment options for low vision may include the use of corrective lenses, magnifying glasses, or other visual aids, as well as occupational therapy and counseling to help individuals adapt to their visual limitations.

Optic neuropathy, ischemic refers to a type of damage to the optic nerve caused by a lack of blood flow to the nerve. This can be due to a variety of factors, including blockages in the blood vessels that supply blood to the optic nerve, high blood pressure, diabetes, and certain medications. Symptoms of ischemic optic neuropathy may include vision loss, pain in the eye, and sensitivity to light. Treatment may involve medications to lower blood pressure or blood sugar, as well as surgery to improve blood flow to the optic nerve. In some cases, vision loss may be permanent.

Perceptual disorders refer to a group of conditions that affect an individual's ability to perceive and interpret sensory information from the environment. These disorders can affect any of the five senses: sight, hearing, taste, smell, and touch. Perceptual disorders can be caused by a variety of factors, including brain injury, neurological disorders, genetic factors, and exposure to toxins or drugs. They can also be caused by psychological factors, such as anxiety or depression. Symptoms of perceptual disorders can vary depending on the type of disorder and the sense that is affected. For example, individuals with visual perceptual disorders may experience difficulty distinguishing colors, shapes, or movement, while those with auditory perceptual disorders may have trouble distinguishing speech sounds or understanding conversations in noisy environments. Treatment for perceptual disorders depends on the underlying cause and the severity of the symptoms. In some cases, medications or other medical interventions may be used to address the underlying condition. In other cases, therapy or counseling may be recommended to help individuals learn coping strategies or adapt to their perceptual limitations.

Low tension glaucoma, also known as normal tension glaucoma or ocular hypertension, is a type of glaucoma in which the intraocular pressure (IOP) is within the normal range but still causes damage to the optic nerve and results in vision loss. The exact cause of low tension glaucoma is not fully understood, but it is believed to be related to a combination of genetic and environmental factors. Risk factors for developing low tension glaucoma include older age, African American race, and a family history of the condition. Treatment for low tension glaucoma typically involves medications to lower the IOP, as well as regular monitoring of the eye to detect any changes in vision or optic nerve damage.

Retinal diseases refer to a group of medical conditions that affect the retina, which is the light-sensitive layer of tissue at the back of the eye. The retina is responsible for converting light into electrical signals that are transmitted to the brain, where they are interpreted as visual images. Retinal diseases can affect any part of the retina, including the photoreceptor cells (rods and cones), the blood vessels, and the supporting cells. Some common types of retinal diseases include: 1. Age-related macular degeneration (AMD): A progressive disease that affects the central part of the retina, leading to vision loss. 2. Diabetic retinopathy: A complication of diabetes that can cause damage to the blood vessels in the retina, leading to vision loss. 3. Retinal detachment: A condition in which the retina separates from the underlying tissue, leading to vision loss if left untreated. 4. Retinitis pigmentosa: A group of inherited retinal diseases that cause progressive vision loss due to the death of photoreceptor cells. 5. Cataracts: A clouding of the lens in the eye that can cause vision loss. Retinal diseases can be treated with a variety of methods, including medication, laser therapy, surgery, and lifestyle changes. Early detection and treatment are crucial for preserving vision in people with retinal diseases.

Blindness, Cortical refers to a type of vision loss that occurs when there is damage to the visual cortex, which is the part of the brain responsible for processing visual information. This type of blindness is often caused by an injury to the brain, such as a stroke or traumatic brain injury, or by a genetic disorder that affects the development of the visual cortex. People with cortical blindness may have difficulty recognizing objects, faces, or letters, and may have trouble with spatial awareness and depth perception. They may also have difficulty with tasks that require fine motor skills, such as writing or using a computer mouse. Treatment for cortical blindness depends on the underlying cause of the condition. In some cases, rehabilitation therapy may be helpful in improving visual function and compensating for the loss of vision. In other cases, medications or surgery may be used to treat the underlying cause of the condition.

Pyrethrins are a group of natural insecticides derived from the flowers of the Chrysanthemum cinerariaefolium plant. They are commonly used in household and agricultural insecticides due to their effectiveness against a wide range of insects, including mosquitoes, flies, ants, and spiders. Pyrethrins work by disrupting the nervous system of insects, causing paralysis and death. They are non-toxic to humans and most mammals, but can be harmful to fish and other aquatic organisms if they enter waterways. Pyrethrins are often combined with other chemicals, such as piperonyl butoxide, to increase their effectiveness and prolong their duration of action. However, prolonged exposure to pyrethrins can cause skin irritation and respiratory problems in some individuals.

Papilledema is a condition in which the optic disc (the part of the eye that contains the nerve fibers that carry visual information from the eye to the brain) becomes swollen and enlarged. This swelling is caused by increased pressure within the skull, which can be due to a variety of factors such as brain tumors, hydrocephalus (an accumulation of fluid in the brain), or other conditions that cause increased pressure within the skull. Papilledema can cause vision loss and other visual symptoms, and it is typically diagnosed through a comprehensive eye exam and imaging tests such as MRI or CT scans. Treatment for papilledema depends on the underlying cause and may include medications, surgery, or other interventions to reduce pressure within the skull.

Refractive errors are a group of conditions that affect the way light passes through the eye and reaches the retina. The retina is a light-sensitive tissue at the back of the eye that converts light into electrical signals that are sent to the brain for processing. When light does not pass through the eye correctly, it can result in refractive errors. Refractive errors can be classified into three main categories: myopia (nearsightedness), hyperopia (farsightedness), and astigmatism. Myopia occurs when the eye is too long or the cornea is too curved, causing light to focus in front of the retina instead of on it. Hyperopia occurs when the eye is too short or the cornea is too flat, causing light to focus behind the retina instead of on it. Astigmatism occurs when the cornea is irregularly shaped, causing light to focus unevenly on the retina. Refractive errors can be corrected with glasses, contact lenses, or refractive surgery. The type of correction needed depends on the severity and type of refractive error, as well as the individual's visual needs and lifestyle. Regular eye exams are important for detecting and managing refractive errors to prevent vision loss and maintain good eye health.

Optic neuritis is a medical condition that affects the optic nerve, which is responsible for transmitting visual information from the eye to the brain. It is characterized by inflammation and swelling of the optic nerve, which can cause a range of symptoms, including vision loss, pain, and sensitivity to light. The exact cause of optic neuritis is not always clear, but it is often associated with viral infections, such as herpes simplex virus, or with autoimmune disorders, such as multiple sclerosis. Other possible causes include exposure to certain medications or toxins, head injuries, and certain genetic conditions. Treatment for optic neuritis typically involves managing symptoms and addressing any underlying causes. This may include medications to reduce inflammation and pain, as well as physical therapy or other supportive measures to help patients recover from vision loss. In some cases, corticosteroids may be used to reduce inflammation and speed up recovery. However, the long-term prognosis for optic neuritis can vary depending on the underlying cause and the severity of the symptoms.

Amblyopia, also known as lazy eye, is a condition in which one eye fails to develop normal vision while the other eye develops normal vision. This can occur due to a variety of factors, including strabismus (crossed eyes), anisometropia (unequal refractive errors), or a lack of visual input from one eye due to a cataract or other ocular condition. In amblyopia, the brain may not properly integrate the visual information from the affected eye, leading to reduced visual acuity and a decreased ability to see details. Amblyopia can be treated with a combination of glasses or contact lenses, patching the healthy eye, and vision therapy. If left untreated, amblyopia can lead to permanent vision loss in the affected eye.

Color vision defects, also known as color blindness, are conditions in which an individual has difficulty distinguishing between certain colors or perceiving colors in a different way than others. This can be caused by a variety of factors, including genetic mutations, eye diseases, exposure to certain chemicals or toxins, and head injuries. There are several different types of color vision defects, including red-green color blindness, blue-yellow color blindness, and total color blindness. Red-green color blindness is the most common type, and it affects the ability to distinguish between red and green colors. Blue-yellow color blindness affects the ability to distinguish between blue and yellow colors, while total color blindness, also known as achromatopsia, affects the ability to see any colors at all. Color vision defects can have a significant impact on an individual's daily life, as they can make it difficult to perform certain tasks, such as driving, reading, or identifying certain types of materials. In some cases, color vision defects may also be a sign of an underlying medical condition, such as a retinal disease or a neurological disorder, and it is important for individuals with color vision defects to see an eye doctor for a proper diagnosis and treatment.

Pupil disorders refer to any abnormality or dysfunction of the pupil, which is the black circular opening in the center of the iris of the eye. The pupil is controlled by the autonomic nervous system and plays a crucial role in regulating the amount of light that enters the eye and adjusting the focus of the lens. Pupil disorders can be caused by a variety of factors, including neurological disorders, eye injuries, infections, and certain medications. Some common pupil disorders include: 1. Anisocoria: This is a condition where the pupils are not the same size. It can be caused by a variety of factors, including neurological disorders, eye injuries, and certain medications. 2. Pupil dilation: This is a condition where the pupils are abnormally large. It can be caused by a variety of factors, including neurological disorders, eye injuries, and certain medications. 3. Pupil constriction: This is a condition where the pupils are abnormally small. It can be caused by a variety of factors, including neurological disorders, eye injuries, and certain medications. 4. Pupil irregularities: This is a condition where the pupils are not round or have irregular shapes. It can be caused by a variety of factors, including neurological disorders, eye injuries, and certain medications. Pupil disorders can affect vision and can be a sign of a more serious underlying condition. Treatment depends on the underlying cause and may include medications, surgery, or other interventions.

Disease progression refers to the worsening or progression of a disease over time. It is a natural course of events that occurs in many chronic illnesses, such as cancer, heart disease, and diabetes. Disease progression can be measured in various ways, such as changes in symptoms, physical examination findings, laboratory test results, or imaging studies. In some cases, disease progression can be slowed or stopped through medical treatment, such as medications, surgery, or radiation therapy. However, in other cases, disease progression may be inevitable, and the focus of treatment may shift from trying to cure the disease to managing symptoms and improving quality of life. Understanding disease progression is important for healthcare providers to develop effective treatment plans and to communicate with patients about their condition and prognosis. It can also help patients and their families make informed decisions about their care and treatment options.

Strabismus is a medical condition in which the eyes are not aligned properly, causing them to point in different directions. This can result in double vision, difficulty seeing in depth, and other visual problems. Strabismus can be caused by a variety of factors, including muscle weakness or paralysis, nerve damage, or problems with the brain's visual processing centers. Treatment for strabismus may include glasses, patches, eye exercises, or surgery, depending on the underlying cause and severity of the condition.

Corticosterone is a steroid hormone produced by the adrenal cortex in response to stress. It plays a key role in the body's stress response and helps regulate metabolism, immune function, and blood pressure. Corticosterone is also involved in the development and maintenance of bone tissue, and it has anti-inflammatory effects. In the medical field, corticosterone is used to treat a variety of conditions, including adrenal insufficiency, allergies, and autoimmune disorders. It is available as a prescription medication and is typically administered orally or by injection.

Glaucoma, Angle-Closure is a type of glaucoma that occurs when the angle between the iris and the cornea becomes blocked, leading to an increase in pressure within the eye. This pressure can damage the optic nerve, which can result in vision loss or blindness if left untreated. Angle-closure glaucoma is a medical emergency that requires immediate treatment to prevent permanent vision loss. It is more common in people of Asian descent and is often associated with certain eye conditions, such as narrow angles or high myopia. Treatment options for angle-closure glaucoma include laser therapy, medication, and surgery.

Optic atrophy is a condition in which the optic nerve, which carries visual information from the eye to the brain, is damaged or degenerated. This can result in vision loss or blindness, depending on the severity of the damage. There are several types of optic atrophy, including primary optic atrophy, which is caused by damage to the optic nerve itself, and secondary optic atrophy, which is caused by damage to the eye or surrounding structures that affects the optic nerve. Some common causes of optic atrophy include glaucoma, head injuries, infections, and inherited genetic disorders. Treatment for optic atrophy depends on the underlying cause and may include medications, surgery, or other interventions to slow or prevent further damage to the optic nerve.

Eye diseases refer to any medical conditions that affect the eyes, including the structures and tissues that make up the eye, as well as the visual system. These conditions can range from minor irritations and infections to more serious and potentially blinding conditions. Some common examples of eye diseases include: 1. Cataracts: A clouding of the lens in the eye that can cause vision loss. 2. Glaucoma: A group of eye diseases that can damage the optic nerve and lead to vision loss. 3. Age-related macular degeneration: A progressive eye disease that affects the central part of the retina and can cause vision loss. 4. Diabetic retinopathy: A complication of diabetes that can damage the blood vessels in the retina and lead to vision loss. 5. Retinitis pigmentosa: A genetic disorder that causes progressive vision loss. 6. Conjunctivitis: An inflammation of the conjunctiva, the thin, clear membrane that covers the white part of the eye. 7. Uveitis: An inflammation of the middle layer of the eye, including the iris, ciliary body, and choroid. 8. Corneal dystrophies: A group of inherited conditions that cause abnormal growth of the cornea, the clear front part of the eye. 9. Optic neuritis: An inflammation of the optic nerve that can cause vision loss. 10. Strabismus: A condition in which the eyes do not align properly, which can cause double vision. These are just a few examples of the many eye diseases that can affect people. Early detection and treatment are important for preventing vision loss and preserving sight.

"Visual Field Testing". January 2, 2013. Siverstone, DE, Hirsch, J: Automated Visual Field Testing. Appelton-Century Croft. ... Machine-based tests aid diagnostics by allowing a detailed printout of the patient's visual field. Other names for this test ... Perimetry more carefully maps and quantifies the visual field, especially at the extreme periphery of the visual field. The ... Techniques used to perform this test include the confrontation visual field examination (Donders' test). The examiner will ask ...
Visual perception Field dependence Corbett, J.; Enns, J. (2006). "Observer pitch and roll influence: The rod and frame illusion ... The rod and frame test is a psychophysical method of testing perception. It relies on the use of a rod and frame apparatus ... These findings suggest that the rod and frame illusion is processed in a type of hierarchy, where visual input is at the top, ... The methods of constant stimuli, limits, and adjustment can be used to test the participants, but method of limits is most ...
Malone BJ, Kumar VR, Ringach DL (2007). "Dynamics of Receptive Field Size in Primary Visual Cortex". Journal of Neurophysiology ... Toxicology testing, also known as safety testing, is conducted by pharmaceutical companies testing drugs, or by contract animal ... Over 20,000 rabbits were used for animal testing in the UK in 2004. Albino rabbits are used in eye irritancy tests (Draize test ... Most tests involve testing ingredients rather than finished products, but according to BUAV, manufacturers believe these tests ...
Neuroscience, Visual perception, Vision, Medical tests, Pathology). ... If a visual stimulus appears in the left visual field (LVF), the visual information is initially projected to the right ... if a visual stimulus appears in the right visual field (RVF), the visual information is initially received by the left cerebral ... The Divided Visual Field Paradigm is an experimental technique that involves measuring task performance when visual stimuli are ...
Some common tests that measure visual health include visual acuity tests, refraction tests, visual field tests and colour ... Visual field tests detect any gaps in peripheral vision. In healthy normal vision, an individual should be able to partially ... Visual acuity tests are the most common tests and they measure the ability to bring details into focus at different distances. ... The testing is completed after listening to a range of pitches. Each ear is tested individually. During the tuning fork test, ...
Functional tests may include electroretinogram and visual field testing. Diagnostic confirmation and an estimation of disease ... If tested in the prodromal phase, cerebrospinal fluid pleocytosis is found in more than 80% of cases, with mainly lymphocytes. ... Visual prognosis is generally good with prompt diagnosis and aggressive immunomodulatory treatment. Inner ear symptoms usually ... In 70% of VKH cases, the onset of visual blurring is bilaterally contemporaneous; if initially unilateral, the other eye is ...
Confrontation visual field testing is a simple and quick visual field assessing method. A confrontational field test requires ... Visual system Visual field Visual field test Eye examination AK Khurana (31 August 2015). "Neuro-ophthalmology". Comprehensive ... causes loss of vision of the right half of the right visual field and the left half of the left visual field. This visual field ... Since the test is basically comparison of the patient's visual field with the examiner's visual field, it is not an accurate ...
The visual field can be considered to be all parts of the sphere for which the observer can see a particular test stimulus. If ... Test stimuli can be displayed on the hemisphere. To specify loci in the visual field, a polar coordinate system is used, all ... at topographically defined loci in the visual field. The visual field is that portion of the external environment of the ... The visual field in this case is all of the external environment that can project light onto the retina. Meridians correspond ...
... test Humphrey visual field analyser Biased competition theory Divided visual field paradigm Receptive field ... In optometry, ophthalmology, and neurology, a visual field test is used to determine whether the visual field is affected by ... Look up visual field or field of vision in Wiktionary, the free dictionary. MedlinePlus Encyclopedia: Visual Field Patient Plus ... The binocular visual field is the superimposition of the two monocular fields. In the binocular field, the area left of the ...
... a visual field test, which assesses peripheral vision; and imaging tests of the optic nerve. Treatment for uveitic glaucoma ... Uveitic glaucoma patients are at significantly higher risk for visual field loss in the long term (>5 years) compared to ... Uveitic glaucoma patients are at significantly higher risk for visual field loss in the long term compared to patients who only ... TGIS uses a visual analog scale to enable pattern recognition-based evaluation of ACC density during a uveitic flare-up. This ...
Confirmation is either via blood tests or direct visual inspection using dark field microscopy. Blood tests are more commonly ... Blood tests are divided into nontreponemal and treponemal tests. Nontreponemal tests are used initially and include venereal ... Diagnosis is usually made by using blood tests; the bacteria can also be detected using dark field microscopy. The Centers for ... Because of the possibility of false positives with nontreponemal tests, confirmation is required with a treponemal test, such ...
Carroll JN, Johnson CA (22 August 2013). "Visual Field Testing: From One Medical Student to Another". Khurana AK, Khurana B (31 ... In glaucoma visual field defects result from damage to the retinal nerve fiber layer. Field defects are seen mainly in primary ... The temporal islands lie outside of the central 24 to 30° visual field, so it may not be visible with standard central field ... and visual field testing. Glaucoma has been classified into specific types: Primary glaucoma (H40.1-H40.2) Primary open-angle ...
... a visual field defect at or surrounding the point of fixation. This pattern can be revealed via visual field testing. Upon ... Loss of visual acuity may start with a blur or haze at the point of fixation, followed by a progressive decline. The degree of ... Further testing, guided by the medical history and physical examination, can be performed to elucidate a specific toxin or ... Examples include blood testing for methanol levels or vitamin B12 levels. Treatment of toxic and nutritional optic neuropathy ...
Visual field testing can confirm the extent of visual loss.[citation needed] No proved treatment exists for branch retinal ... Abrupt painless loss of vision in the visual field corresponding to territory of the obstructed artery is the typical history ... Ancillary testing is not usually necessary to make the diagnosis. Fluorescein angiography reveals an abrupt diminution in dye ... Patients can typically define the time and extent of visual loss precisely.[citation needed] Retinal whitening that corresponds ...
... is a method to test for visual field loss, usually in glaucoma testing or monitoring. It is combined with a visual field test ... This results in a shorter test time with reportedly equal accuracy as other automated threshold visual fields. Bengtsson, Boel ... In this manner, it can reduce the time necessary to acquire a visual field by up to 50%, and it decreases patient fatigue and ... The testing mode interrupts testing when measurement error is reached. ...
Visual snow: dynamic, continuous, tiny dots in the entire visual field lasting more than three months. The dots are usually ... Symptoms are not better explained by another disorder (ophthalmological, drug abuse). Normal ophthalmology tests (best- ... visual field, and electroretinogram); not caused by previous intake of psychotropic drugs. Additional and non visual symptoms ... two studies found white matter alterations in parts of the visual cortex and outside the visual cortex in patients with visual ...
Abnormal results on color vision or visual field testing is not uncommon. Visual field often presents as constricted 'tubular' ... and a reduced visual field (tubular or spiral field). Streff Syndrome was first described in 1962 by an optometrist, Dr. John ... at multiple test distances. The poor visual performance is understood as distress, and treatments are usually to provide the ... Streff believed the visual changes were induced by stress from reading. There is dispute on the taxonomy of functional vision ...
For example, visual field testing might demonstrate homonymous hemianopsia with macular sparing.) In the case of ... Visual input from the macula occupies a substantial portion of the brain's visual capacity. As a result, some forms of visual ... Tyler, C.W.; Hamer, R.D. (1990). "Analysis of visual modulation sensitivity. IV. Validity of the Ferry-Porter law". Journal of ... Remington, Lee Ann (2011). Clinical Anatomy of the Visual System. Elsevier Health Sciences. pp. 314-315. ISBN 978-1-4557-2777-3 ...
Formal visual field testing by perimetry is recommended, as this would show evidence of optic nerve compression by a tumor. ... The insulin tolerance test is discouraged in children. None of the tests for ACTH deficiency are perfect, and further tests ... Stimulation tests were developed in the 1960s, and in 1973 the triple bolus test was introduced, a test that combined ... Alternative tests (such as the growth hormone releasing hormone stimulation test) are less useful, although a stimulation test ...
The test is not sensitive to the location of brain-damage (except for damage comprising part of the visual field). It consists ... Digit symbol substitution test (DSST) is a neuropsychological test sensitive to brain damage, dementia, age and depression. ... contains an optional implicit learning test: after the Digit Symbol-Coding test paired and free recall of the symbols is ... Four boxes test Lezak, M.D.; Howieson, D.B. & Loring, D.W. (2004). Neuropsychological assessment. New York: Oxford University ...
... Carroll, J. N., & Johnson, C. A. (2013, August 22). Visual Field Testing: ... Macular sparing is visual field loss that preserves vision in the center of the visual field, otherwise known as the macula. It ... particularly if they lose vision in their right visual field. This is because the right visual field projects to the left ... Macular sparing can be determined with visual field testing. The macula is defined as an area of approximately + 8 degrees ...
... visual field tests are a good screen to test for chiasmal involvement. Visual fields tests will delineate chiasmal syndromes ... allows the left half of the visual field to end up on the right side of the brain and the right half of the visual field to ... Visual field defects may be one of the first signs of non-functional pituitary tumor. These are much less frequent than ... Visual fields associated with chiasmal syndrome usually leads to an MRI. Contrast can delineate arterial aneurysms and will ...
Visual field tests may also show an enlarged blind spot or a decrease in visual clarity. Often, doctors may order blood tests ... A test called flourescein angiography uses a special dye and camera to study blood flow in the back layers of the eye. When a ... The low dose of steroids can help decrease inflammation, and as a result, lessens the visual impairment. In the event steroids ...
... usually help detecting defects in central 20 degrees of the visual field. In the test, the person looks with each ... who used a similar small card with a grid pattern to be kept in the center of the visual field testing instrument perimeter. ... "Efficacy of the Amsler Grid Test in Evaluating Glaucomatous Central Visual Field Defects". Ophthalmology. 123 (4): 737-743. doi ... A color version with a blue and yellow grid is more sensitive and can be used to test for a wide variety of visual pathway ...
As expected, visual field testing in cone dystrophy usually reveals a central scotoma. In cases with the typical bull's-eye ... Color vision testing using color test plates (HRR series) reveals many errors on both red-green and blue-yellow plates. ... Visual acuity usually deteriorates gradually, but it can deteriorate rapidly to 20/200; later, in more severe cases, it drops ... Abnormal cone function on the ERG is indicated by a reduced single-flash and flicker response when the test is carried out in a ...
... up the number of fingers the investigator is presenting If patient is not responsive the visual fields can be tested by visual ... If the patient has isolated peripheral nerve paresis assign a score of 1 Assess the patient's vision in each visual fields. ... Each eye is tested individually, by covering one eye and then the other. Each upper and lower quadrant is tested by asking the ... Level of consciousness (LOC) testing is divided into three sections. The first LOC items test for the patient's responsiveness ...
This includes localized reductions in light sensitivity as assessed by visual field testing (microperimetry). Lasting problems ... A blurred or gray spot in the central visual field is common when the retina is detached. Reduced visual acuity may persist ... However, some visual abnormalities can remain even where visual acuity is measured at 20/20. ... The angiography test will usually show one or more fluorescent spots with fluid leakage. In 10%-15% of the cases these will ...
Improvement can be determined by visual acuity, visual field testing, and by ophthalmoscopic examination. At a later stage, pan ... The visual prognosis for ocular ischemic syndrome varies from usually poor to fair, depending on speed and effectiveness of the ... The condition presents with visual loss secondary to hypoperfusion of the eye structures. The patient presents with intractable ...
... the subject's eyes are subject to a moving visual field while the subject remains stationary. The speed of the drum and the ... optokinetic drum was used to test the symptoms of the sopite syndrome showed increased mood changes in response to the visual ... In the case of Space Motion Sickness, the unweighting of otolith organs can lead to a sensory mismatch between the visual, ... The sopite syndrome may be difficult to test due to the nature of the symptoms. Indicators such as drowsiness, mood changes, ...
... visual field loss management and accommodative therapy. They often do standard eye and vision testing along with computerised ... Visual therapy in children is performed by optometrists who specialize in children's eye care. To specialize in vision therapy ... This type of therapy is however generally used in patients who need visual correction but for whom the corrective lenses are ... They may also order imaging tests (CT/MRI), remove ocular foreign bodies and perform some laser procedures. They are also ...
Central and peripheral vision is tested by using visual field tests. Changes may indicate eye diseases, such as glaucoma or ... Central and peripheral vision is tested by using visual field tests. Changes may indicate eye diseases, such as glaucoma or ...
Societal Impact Synthetic Aperture Radar Tuberculosis UAV Drones UAV Motion Unmanned Technologies Virtual Reality Visual ...
Our experts explain what a visual field test is and why it is important in detecting types of eye injury and disease, such as ... Why do I need a visual field test?. Your optometrist uses the visual plot field to compare your visual field test to others ... What is a visual field test?. A visual field test is a simple test which measures your peripheral vision and all-around vision ... What can a visual field test detect?. A visual field test can detect vision loss caused by a possible brain tumour, stroke or ...
A visual fields test is a non-invasive diagnostic test which can identify many problems, not only eye diseases but neurological ... Brain tumours, strokes and glaucoma, amongst other things, can be detected using this simple test. ...
Visual fields testing is important. But it is a late sign of glaucoma, when many nerve cells in retina die. Increased eye ... is a key test for glaucoma diagnosis. OCT looks at your retinal nerve fiber for indicators of glaucoma process. ... Glaucoma diagnostic tests. Visual fields testing. Optical Coherence Tomography, OCT. 2 Can we help? .button { background-color ... Visual fields testing is important. But it is a late sign of glaucoma, when many nerve cells in retina die. ...
Simulation of a Visual Field Test. To which of you that want to experience in a visual field test, and feel what happens in ... imaging which would augment the information given by the visual field test. Consequently, the frequency of visual field tests ... It is interesting to point out that while the visual field test is subjective and analyzes visual function, such imaging tests ... Further information regarding the visual field test, see the following chapter:Deterioration of the visual field in glaucoma. ...
Visual field testing. Perform automated threshold testing (eg, Humphrey 24-2) to rule out any glaucomatous visual field defects ... If the Humphrey visual field testing results are normal, SWAP should be considered to help detect visual field loss earlier. ... In some patients with glaucoma, the addition of a 10-2 visual field (VF) test to the standard 24-2 VF test or modification of ... The rate of progression of visual field loss, as measured by mean deviation, is related to the amount of visual field loss ...
Engineering Report and Testing. *Visual inspection and field services. *Ultrasonic inspection. *3D Lighting ...
Laboratory-testing; Simulation-methods; Measurement-equipment; Equipment-design; Visual-fields; Visual-motility; Physiological- ... but not across the two tablets tested.Wrist extension was high for all configurations and particularly for the dominant hand ... measurements; Physiological-testing; Muscle-function; Muscles; Computer-software; Author Keywords: Slate computing; media ...
... virtual reality visual field testing is poised to challenge traditional methods of monitoring patients with glaucoma. ... will revolutionize our approach to testing. We look forward to adding VR visual field testing to diagnostic offerings for our ... Mobile or home-based testing could facilitate closer monitoring of visual field loss and alert physicians to patients who need ... One area that is particularly ripe for disruption is perimetry testing. Virtual-reality (VR) visual field monitoring could ...
A fundus examination revealed bilateral optic disk swelling and peripapillary retinitis; visual field testing revealed ... A treponemal test reacted negatively to a nontreponemal Venereal Disease Research Laboratory (VDRL) test in serum, but a VDRL ... and visual fields remained stable 3 months after penicillin treatment was begun (Appendix). Lumbar puncture at that time ... Visual acuity was 20/32 in the right eye and 20/63 in the left. Pupils were equal and reactive to light, with no relative ...
From 2005 to 2008, NHANES also implemented a retinal imaging module and a visual field-testing module. ... Best-corrected Visual Acuity. VIDROVA - Right visual acuity, w/ obj. refraction;. VIDLOVA - Left visual acuity, w/ obj. ... Presenting Visual Acuity. VIDRVA - Right visual acuity, presenting;. VIDLVA - Left visual acuity, presenting. Ages 12+. ... Presenting visual acuity ≤20/50. Best-corrected visual acuity ,20/40 with refraction. Ages 12+. ...
View other providers who treat Visual Field Defects Cognitive Function Testing ... Rajul Parikh, MD is a clinical neurophysiologist in Orange Park, FL and has over 20 years of experience in the medical field. ... View other providers who treat Grip and-or Muscle Group Pull Test ... does have one theyve taken the extra step to master their specialty and to keep up with the latest advancements in their field ...
Virtual Reality Visual Field Test Device in Healthcare. March 22, 2023. News ... I am now getting excited about whats happening in the test tube, or on slides under the microscope or in faint hints on the ...
the time of the visual field test (in days from baseline visit) and Location. the spatial location on the visual field that the ... The figure above demonstrates the visual field from a Humphrey Field Analyzer-II testing machine, which generates 54 spatial ... is a function that plots the observered visual field data over time at each location on the visual field. ... represents the visual field test visit number, DLS. the observed outcome variable, differential light sensitvity, Time. ...
2. Visual field test scoring and reliability. Ophthalmology 1994;101:1445-1455. ... Two-Year Randomized, Placebo-Controlled Study of Black Currant Anthocyanins on Visual Field in Glaucoma Subject Area: ... Ogawa T, Ogawa A, So K: Target intraocular pressure and risk factors for progression of visual field loss in primary open-angle ... Hart WM, Becker B: The onset and evolution of glaucomatous visual field defect. Ophthalmology 1982;89:268-279. ...
Illustration of visual field test results from a Humphrey field analyser (HFA) and the eye tracking-based visual field analysis ... A widely used technique in trying to improve the visual field in patients suffering from visual field defects is visual ... Visual field test result of the left eye of participant 12-showing diagnostics sheets from a Humphrey field analyser (left ... of the upper visual field and p12 was invited to undergo the analysis once more and additionally conduct a visual field test ...
Visual Field Testing * Well Child Exam Show All button Press enter to expand Show Less ...
Eye floaters are often described as black spots or squiggly strands in a patients field of vision. Read about causes, symptoms ... visual field testing to assess loss of central or peripheral vision,. *retinal tomography imaging to determine the thickness of ... Additional testing may be recommended by your eye-care professional. These tests may include ...
Visual field testing / Optic Nerve scanning. *Macular Degeneration evaluation *Retinal OCT mapping ...
His neurological examination and visual field test were normal. Emergent MRI of the sella disclosed an enhancing intrasellar ... Fifteen days later, the clinical visual acuity examination showed a significant improvement in the patient with visual field ... The tumor caused a loss of visual field of the right side. Cabergoline treatment was started with dose of 1.5 mg/week. ... Rapid improvement in visual loss with cabergoline treatment in a giant prolactinoma case: 5 years survey.. Tasan E, Hanimoglu H ...
... out glaucoma in myopic eyes often poses a diagnostic challenge because of atypical optic disc morphology and visual field ... Predictive Value of Tests * Reproducibility of Results * Retinal Ganglion Cells / pathology* * Sensitivity and Specificity ... final classification of myopic glaucoma or myopic control was based on consensus assessment by 3 clinicians of visual fields ... 1 Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Nova Scotia, Canada; NIHR Biomedical Research ...
... This multiple-star system will push the limits of your vision. ... Whats more, anyone trying to split Orions Theta stars under a dark sky will discover a visual impediment: the surrounding ... Herringtons observation is especially revealing and speaks volumes about her visual acuity. "Ive never really been able to ... giving it an extra visual kick. (Theta2 Ori C, the other component of Theta2 Ori, is below naked-eye visibility at 8th ...
At 107 sites visual motion discrimination was tested and 37 locations were examined for aphasia testing. During the tests ... Visual motion blindness was primarily observed in the contralateral visual field, but at specific sites it was also present in ... Although visual motion blindness was primarily observed in the contralateral visual field, stimulation of hMST also affected ... Although visual motion blindness was predominantly observed in the contralateral visual field, stimulation of hMST also ...
The aim of the study was to evaluate changes in the central visual pathways during the early and advanced stages of bilateral ... The Humphrey visual field test 24-2 was performed on all patients The VF results were evaluated and the diagnosis was confirmed ... primary visual cortex receive information from both the nasal visual field of the ipsilateral eye and the temporal visual field ... Functional MRI signal changes in primary visual cortex corresponding to the central normal visual field of patients with ...
The QC is a subset of QA intended to capture errors in processing data through testing and preventive processes to identify ... J. L. Keltner, C. A. Johnson, K. E. Cello et al., "Visual field quality control in the ocular hypertension treatment study ( ... flowchart of tests, and interviews. This enabled a more thorough QC that led to the creation of field diaries, which were ... and testing related to long-term; data collection, clinical laboratory test results, storage biobank samples, and other issues ...
  • Brain tumours, strokes and glaucoma, amongst other things, can be detected using this simple test. (
  • Standard automated perimetry (SAP) is the most common method for detecting visual field damage in glaucoma patients, but this method is not as effective in detecting early changes, which are often more structural than functional. (
  • They investigated the ability of FDT and SAP to detect visual field damage, finding that the difference between these two methods may be useful in identifying risk factors in glaucoma patients. (
  • Cite this: Virtual Reality Takes the Field in Glaucoma - Medscape - Jun 06, 2023. (
  • a glaucoma survey house-to-house, it is es- a variety of tests are used and hence inter- sential to have portable tools. (
  • The aim of the study was to evaluate changes in the central visual pathways during the early and advanced stages of bilateral normal-tension glaucoma (NTG). (
  • This patient has an increased risk of developing glaucoma OS and must be routinely followed with intraocular measurements, optic nerve exam, gonioscopy, and visual field testing. (
  • Severe visual loss if associated with untreated glaucoma. (
  • Testing for glaucoma typically begins with measuring the pressure inside the eyes. (
  • Visual acuity tests measure the sharpness of vision and are usually performed using a projected eye chart to measure the distance visual acuity and a hand-held small acuity chart to measure the near vision (for reading). (
  • Distance and near vision acuity tests in ON for determining the sharpness or clarity of your reading and distance vision. (
  • The printed page summarizing the results of the test includes a map composed of different shades, accompanied by various mathematical calculations and statistical analyses, enabling your physician to visualize any defects in your visual field. (
  • The VR headset had difficulty capturing and would at times underestimate more profound defects in the visual field or miss isolated defects. (
  • The QC is a subset of QA intended to capture errors in processing data through testing and preventive processes to identify problems, defects, or intended requirements. (
  • Testing was accomplished as a subset of QC as preventive operations that ensured the identification of problems, errors, and defects in software or predetermined requirements. (
  • These visual field defects can join together to form a ring scotoma. (
  • How does the doctor determine the diagnosis from the information acquired during a visual field test? (
  • Most patients will be more than happy to skip this test, but it is an essential part of your examination since it provides crucial information, initially for the diagnosis of the disease and later to assess whether progression had occurred. (
  • They include tests that establish the diagnosis of POI/POF, tests that help clarify the etiology, and screening tests for other diseases known to have higher prevalence among women with POI/POF. (
  • Ovarian antibodies: Currently, no reliable ovary-specific tests exist for the diagnosis of autoimmune ovarian failure. (
  • Because of the wide variety of subtypes of so-called RP or related pigmentary retinopathies, the definitive test for diagnosis is identifying the particular genetic defect. (
  • Only an eye care professional can provide a full diagnosis of visual problems. (
  • Results from the proposed research can potentially lead to translational applications in the diagnosis and treatment of binocular visual disorders, offering additional and important training in linking vision research to clinical practie. (
  • The aim ers after reviewing the relevant visual field due to damage to the optic of the current study was to evaluate the literature. (
  • Central and peripheral vision is tested by using visual field tests. (
  • The visual field test is designed to see how well you see outside of the center part of your vision (peripheral vision). (
  • Some people can have perfectly normal 20/20 central visual acuity and have almost complete loss of their peripheral vision. (
  • Most visual field tests are now done on an automated machine that flashes lights in your peripheral vision while you stare straight ahead. (
  • The machine is trying to find the dimmest light you can see at each point in your peripheral vision that it is testing for. (
  • This test checks for the possible presence of blind spots (scotomas) in the peripheral (side) vision by performing a visual field test. (
  • A visual fields test is a non-invasive diagnostic test which can identify many problems, not only eye diseases but neurological issues too. (
  • The tests described below are useful in excluding masquerading diseases or in detecting conditions that are associated with retinitis pigmentosa (RP). (
  • Visual fields (upper and lower quadrants) are tested by 0 = No visual loss confrontation, using finger counting or visual threat as appropriate. (
  • The most common type of visual field test in a regular eye exam is called confrontation field test in which the doctor flashes several fingers in each of the four quadrants of your visual field while seated opposite you. (
  • What Tests Might I Have During My Eye Exam? (
  • A screening test that checks the color vision is often performed early in a comprehensive eye exam to rule out color blindness. (
  • A comprehensive eye exam can take 1 hour or longer, depending on the number and complexity of tests required to fully evaluate vision and the eyes health. (
  • Neoplasm related laboratory tests: Antiretinal antibodies, particularly antirecoverin antibodies, may be observed, especially in CAR or in severe cases of RP. (
  • To test this hypothesis, we used speech intelligibility and attenuation tests in the laboratory on 26 subjects, and real-time video exposure monitoring in the field (airport maintenance personnel) for visual communication cues. (
  • Each survey involved collecting data by direct physical examination, the taking of a medical history, and laboratory and clinical tests and measurements. (
  • During the test light is projected onto a screen in order to measure the sensitivity of different parts of the retina to light. (
  • ERG is the most critical diagnostic test for RP because it provides an objective measure of rod and cone function across the retina and is sensitive to even mild photoreceptor impairment. (
  • In some cases, VIGADRONE also can damage the central retina and may decrease visual acuity [see WARNINGS AND PRECAUTIONS ]. (
  • In order to advance in Math Twins we will have to pay attention to the visual stimuli that appear on the screen and quickly find the pairs of complementary numbers. (
  • Field names cannot start with a number or contain any spaces or non-alphanumeric characters (except the underscore character "_" is permitted). (
  • Field names cannot have spaces or non-alphanumeric characters other than the underscore. (
  • This area is represented on the visual map as a black round spot, slightly smaller then the size of a 1 shekel coin, located slightly to the left or to the right (depending on the eye) of the centre of the visual field. (
  • Un échantillon choisi à dessein de 50 patients souffrant de glaucome, âgés de 12 à 18 ans, consultant un centre de soins externes en ophtalmologie au Caire (Égypte) a bénéficié d'un programme éducatif sur cette maladie, visant à corriger leurs idées fausses et leurs attentes, et comportant des démonstrations et des formations de perfectionnement sur les soins oculaires. (
  • Patients can go on to develop constricted visual fields or tunnel vision. (
  • VIGADRONE can cause permanent bilateral concentric visual field constriction, including tunnel vision that can result in disability. (
  • Whether attempting to duplicate traditional visual field testing in VR with a consistent fixation point and clicker or by utilizing a proprietary software package to map out a dynamic visual field, VR visual field testing is beginning to approach parity with the traditional perimetry methods. (
  • It is important to explain to these individuals that these feelings are normal reactions to the test, and shared by both sick and healthy patients alike and is due to the fact that during the test the light projected on the screen slowly decreases in intensity, until it becomes harder and harder to detect until completely undetectable. (
  • No matter what your vision is, most lights shined during the test will be, by definition, almost impossible to detect. (
  • Our study aimed to detect if any specific retinal signs can be attributed to past EVD in survivors, to describe the implications for visual acuity, and to assess for EBOV persistence in survivors with cataracts amenable to cataract surgery where no intraocular inflammation was present. (
  • Goldmann (kinetic) perimetry is recommended, as it can more easily detect progressive visual field changes. (
  • This transformation from two monocular views to stable binocular single vision is the manifestation of important neural processes that give rise to significant improvements in visual perception, including stereoscopic depth perception and binocular contrast summation. (
  • The local nature of binocular combination suggests, moreover, that SED may vary idiosyncratically throughout the visual field. (
  • Aim 1 will investigate how patterns of SED vary across visual field locations, and will test for influences of regional SED patterns on binocular function. (
  • Following psychophysical measurements in Aim 1, Aim 2 will apply functional magnetic resonance imaging (fMRI) to test predictions stemming from a simple neural model of binocular integration. (
  • By studying this network under monocular, binocular fusible, and binocular rivalry conditions, the stage of processing giving rise to SED can be isolated, while also revealing how underlying mechanisms vary functionally throughout the visual field. (
  • A test used to assess strabismus or a more subtle binocular vision problem that could cause eye strain or amblyopia (lazy eye). (
  • This is used to test perception of depth and 3-dimensional structure obtained on the basis of visual information deriving from two eyes by individuals with normally developed binocular vision. (
  • They merely represent a general guide: tests carried out professionally by your optician or ophthalmologist are the only way to establish your visual correction needs. (
  • Therefore, it is very important to establish a concise and usable naming convention for your field names when beginning to design your data entry form. (
  • This can be done by the 'puff-of-air' test, based on the eye's resistance to the puff of air, the machine calculates intraocular pressure (IOP). (
  • These results suggest that early visual cortex up to the stage of MT is not sufficient for the perception of global visual motion. (
  • Rather, visual motion information must be mediated to higher-tier cortical areas, including hMST, to gain access to conscious perception. (
  • A pregnancy test (urine or beta human chorionic gonadotropin [bhCG] in the blood) should be the first study performed in every woman of reproductive age who presents with amenorrhea. (
  • Females 12 years and older will have a urine pregnancy test, as well as girls 8-11 who have started their periods. (
  • Visual field testing (40+) rest room, you will provide a urine sample. (
  • The results of each individual eye are registered in print and the patient is requested to give the test results to the ophthalmologist during the patient's next visit. (
  • Blood tests and sometimes biopsy of temporal artery tissue are done to diagnose giant cell arteritis. (
  • Below is a list of tests you will receive on the day of your examination. (
  • Successfully demonstrated a visual field test perimeter using saccadic eye movements to visual targets as detection responses. (
  • Only horizontal eye movements will be tested. (
  • Voluntary or reflexive (oculocephalic) eye movements will be scored but caloric testing is not done. (
  • Mobile or home-based testing could facilitate closer monitoring of visual field loss and alert physicians to patients who need further evaluation. (
  • The full-field ERG in RP typically shows a marked reduction of both rod and cone signals, although rod loss generally predominates. (
  • While this is a promising application of a developing technology, it still needs refinement before it will fully replace the more traditional testing methods. (
  • Since the development and refinement of QA, QC, and testing tools in clinical research, the planning and conduction of large studies improved greatly. (
  • A parallel test of serum estradiol is necessary. (
  • In addition, a large majority of patients, whether healthy or sick, constantly feel that they have preformed poorly on the test. (
  • Therefore, it is crucial that patients continue to undergo these tests as often as the doctor requests them. (
  • It might even be possible for patients to perform preappointment visual field tests at home, allowing their physicians to review the results in advance, streamlining patient visits. (
  • We look forward to adding VR visual field testing to diagnostic offerings for our patients and anticipate that as more practices adopt this technology, the data collected will lead to the continued improvement and increased reliability of the results. (
  • Patients with ocular trauma, bandages, pre-existing blindness or other 2 = Forced deviation, or total gaze paresis not overcome by the disorder of visual acuity or fields should be tested with reflexive oculocephalic maneuver. (
  • therefore, this test is the most useful measure for ongoing follow-up care of patients with RP. (
  • Contrast sensitivity often is reduced out of proportion to visual acuity in patients with RP. (
  • Many patients get anxious when they take this test because everyone wants to do well on it. (
  • This test is useful for children and patients who are unable to accurately answer the doctor's questions. (
  • Ocular motility testing is performed to determine how well eyes can follow a moving object and/or quickly move between and accurately fixate on two separate targets. (
  • Although Epi Info automatically suggests a field name based on the Question or Prompt, it does so by concatenating the first several words together, stripping spaces and invalid symbols. (
  • If your desired field name is invalid for any of the reasons mentioned above, it will appear in red font and the OK button will be disabled. (
  • Goldmann visual fields showed a dense central scotoma in the right eye and a dense cecocentral scotoma in the left. (
  • Some feel anxiety and frustration from not seeing the light properly and some feel that their vision has deteriorated since the last test. (
  • When we test your vision on the basic eye chart it is only testing how well you see right in the center and gives us no idea if you can see out away from the center. (
  • Working closely with proposed research mentor Randolph Blake and interacting with others in the Vanderbilt Vision Research community offers a unique opportunity to expand the applicant's expertise in visual neuroscience. (
  • This test is used to estimate which lens powers will best correct distance vision. (
  • Testing your own vision with different lenses for determining if your vision can be improved or corrected with the help of regular glasses or contact lenses. (
  • According to the findings in the test, the doctor can diagnose the patient, and determine what the best treatment is. (
  • The device can then calculate the minimal intensity of light that a patient can actually see, a separate value for each part of the visual field. (
  • Another notable benefit is that by utilizing dynamic visual field mapping with eye tracking and head positioning information , test duration could be shortened while improving patient engagement and attentiveness. (
  • Both the stimulation of hMT and hMST made it impossible for the patient to perceive the global visual motion of moving random dot patterns. (
  • In these cases, persistent amenorrhea or oligomenorrhea accompanied by menopausal symptoms necessitates a repeat of the above tests in 1-2 months. (
  • In one head-to-head study , VR visual field and traditional perimetry were shown to have high overall field correlation with consistent mean deviations and comparable reliability indices between the two methods. (
  • The study aimed to comprehensively follow-up 10,000 males and females in an exclusive-center, based on interviews and tests of varied complexities and diverse ethnicities over a 10-year period with greatly developed QA, QC, and testing tools among Family Physician Health and Medical Services, private clinics, or organizations with geographically normal distributions of the Shiraz metropolitan city. (
  • Logistic regression was used to analyze the data from the field study. (
  • Refer for genetic counseling and testing for the FMR1 premutation if a family history of POI, mental retardation, or a tremor/ataxia syndrome is present. (
  • For information of some of these common attributes, refer to the Field Attributes topic. (
  • A Field Definition dialog box appears. (
  • The contents of the Field Definition dialog depend on the type of field being added. (
  • Interpreting the results of this test is not an easy task, and it can take doctors who specialize in ophthalmology a few months to learn how to accurately interpret the different information appearing on the printout. (
  • RESULTS: Postures and muscle activity for the wrist significantly varied across configurations and between hands, but not across the two tablets tested.Wrist extension was high for all configurations and particularly for the dominant hand when a tablet was placed on the lap (mean = 38. (
  • Organization (WHO) Eastern Mediterra- the validity of the screening tests. (
  • First, area MT shows a proper retinotopic organization confined to the contralateral visual hemifield, whereas the receptive fields of neurons in area MST, located one synapse downstream from area MT, are much larger. (
  • Fields may have attributes that are specific to the type of data the field will hold. (
  • Click and drag the type of field you want to add from the Project Explorer to the approximate location on the canvas. (
  • Alternatively, right click on the canvas in the approximate location you want to add a field and select the field type from the New Field context menu. (
  • This test involves quickly bringing your two index fingers together. (
  • The interviewer will collect a sample of your household tap water, which we will test for environmental chemicals. (
  • In Epi Info™ 7, different fields are provided to collect different types of information. (
  • DESCRIPTION (provided by applicant): Sensory input to the visual system arises from two separate 'channels' (left and right eyes), yet we experience a single, unitary visual world that belies little hint of the dual monocular origins of that experience. (
  • A test of the fluid pressure within your eyes. (
  • One area that is particularly ripe for disruption is perimetry testing. (
  • Collaborated with Peter Schiller to elucidate the function of visual area three (V3), which involved animal behavioral training, psychophysics and histology. (