PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Visual Fields”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 991 records · Page 55Linked to original sources

Visual field loss and a relative afferent pupillary defect in a patient with optic nerve head drusen.

Optic nerve head drusen often cause several diopters of disc elevation and are important etiology of pseudopapilledema. Compression of nerve fibers between the lamina cribrosa and prelaminar drusen may cause corresponding visual field defects. Significantly asymmetric visual field loss may be associated with a relative afferent pupillary defect. Central visual field loss from optic nerve drusen is a rare phenomenon that requires an extensive ophthalmic work-up to rule out other pathology.

Adult↗

Colour vision as a post-receptoral specialization of the central visual field.

The experiments address the question whether there is evidence that the central visual field is any more specialized for colour than it is for luminance contrast detection. The decline in contrast sensitivity across the visual field for colour-only (red-green) gratings is compared to that for monochromatic luminance gratings at a range of spatial frequencies in the nasal and temporal fields. Measurements are made of the chromatic spatial summation area and the relevant parts of the chromatic temporal contrast sensitivity function at different eccentricities in order to control for their influence on the decline in contrast sensitivity. Results show that at each spatial frequency colour contrast sensitivity declines with eccentricity approximately twice as steeply as luminance contrast sensitivity. The more rapid decline in colour contrast sensitivity than luminance contrast sensitivity across the visual field reveals that chromatic mechanisms are more confined than luminance mechanisms to the central field.

Color Perception↗

[Statistical analysis of visual fields by the automatic perimeter Octopus 2000 R with the Delta program].

The difference tables gives, on a numeric table, the difference between first and second examination. The confidence interval is given out by a statistical test (T-test) which can be applied to the following parts of visual field: pathological area, whole field. We present a number of visual field examinations (Program 33) from glaucomatous patients, analysed through "change mode". We can make the following remarks: When we assess an improvement, it is underlined in "Delta Program", which indicates: significant improvement. When the visual field is unchanged, "Delta Program" indicates a fluctuation: aggravation or improvement (almost always insignificant). A subjective alteration is always underlined by "Delta Program". The program allows an objective interpretation and, when it is combined with the usual objective interpretation, makes the evaluation of campimetric deficiency easier. The importance of statistical analysis, besides the fact that it associates the visual field to one or several mean values, is to set it off as exactly as possible. Flammer and coll. (1985) propose a new index: "corrected loss variation".

Computers↗

Spatio-temporal discrimination of frequency in the right and left visual fields: a preliminary report.

Normal right-handed subjects were presented with luminance patterns varying from sinusoidally in both space and time to the left and right visual fields. With no temporal variation in the stimuli, detection thresholds for the left visual field were lower than those for the right visual field for all spatial frequencies. However, with increasing temporal variations, a reversal in detection of threshold occurred, with the right visual field surpassing the left. This finding suggests that left and right visual processing may be differentially efficient for temporal and spatial visual information.

Adult↗

Testing of concentric visual field constriction by means of scotopic visually evoked potentials.

Using scotopic visually evoked potentials (VEP), an objective test of concentric absolute field defects is presented. At 0.8 log units above the mean VEP threshold, the full field, the central area of 50 degrees diameter, and the complementary peripheral field were flash stimulated. In 13 normal subjects the peripheral VEP response was larger in amplitude and shorter in latency compared to the central response. In four cases of concentric field restriction due to hysteria and malingering, the same results were found. In three cases of retinitis pigmentosa and advanced glaucoma, the peripheral VEP sensitivity was worse than the central one or no response could be found. The amount of stray light was estimated as the difference of the thresholds for central and peripheral stimulation (1.6 to 1.8 log units) in a patient with a residual central field of 20 degrees.

Adolescent↗

[Pathological visual field and brain tumor].

The general relationships between an operatively or autoptically localized tumor and the visual field determined by means of ikineticer perimetry are investigated, the patient stock being a total of 1756 neurosurgical brain-tumor inpatients. Examination of the visual field was possible with four fifths of the brain-tumor patients. Hemianopic, quadrantanopsic, or scotomatous defects of a topically localizable nature could be found in almost one third of the total patient stock available for examination. The clinically particularly interesting criteria of localization of homonymous-hemianopsia defects such as macular sparing and incongruence/congruence of visual field changes should be of no importance to the localization within the visual pathway of brain-tumor patients.

Blindness↗

Patterns of optic disk damage in patients with early focal visual field loss.

PURPOSE: To study the patterns of structural damage of the optic disk in patients with early focal visual field loss using a confocal scanning laser ophthalmoscope. METHODS: Thirty-nine subjects with repeatable early focal visual field loss were included. The Heidelberg Retina Tomograph (Heidelberg Engineering, Heidelberg, Germany) was used to obtain topographic optic disk measurements. For analysis of structural damage, the topographic measurements were divided into 36 10-degree sectors. Sector analysis was performed using sector rim area to sector disk area ratio. Patients were assigned to one of three groups based on the measurement of the optic disk damage: (1) diffuse disk damage; (2) focal disk damage; or (3) no detectable disk damage. RESULTS: Approximately half of the patients with early focal glaucomatous visual field loss showed diffuse optic disk damage, one quarter to one third had focal damage, and one sixth had no detectable damage. Optic disk area was smallest in the no-detectable-damage group (1.71 + 0.19 mm2), followed by the focal-damage group (2.06 + 0.54 mm2), and was largest in the diffuse damage group (2.29 + 0.48 mm2; P = .22). CONCLUSION: In patients with early focal glaucomatous visual field loss, observable optic disk damage can be diffuse, focal, or undetectable. The Heidelberg Retina Tomograph may be capable of detecting different patterns of diffuse or focal structural damage.

Adult↗

Frequency of sustained glaucomatous-type visual field loss and associated optic nerve cupping in Beaver Dam, Wisconsin.

PURPOSE: To determine the prevalence of persisting glaucomatous-type visual field loss in a Midwestern American adult population, in association with four grades of disc cupping. METHODS: On two separate occasions (1988-1990 and 1993-1995) 2955 predominantly Caucasian adults aged 43-84 provided medical history, underwent applanation tonometry, slit-lamp examination, quantitative suprathreshold perimetry and stereoscopic disc analysis as part of the National Institutes of Health-sponsored Beaver Dam Eye Study. Those demonstrating evidence of glaucomatous-type visual field loss at both visits were the subject of the present analysis. Among these individuals, associations were determined for four categories of optic disc cupping (vertical cup/disc < 0.5, > 0.5, > 0.6, > 0.8), intraocular pressure, blood pressure, cardiovascular pathology and prior glaucoma diagnosis. RESULTS: Of the 2955 subjects assessed, 120 (4%; 57 women, 63 men) demonstrated glaucomatous-type visual field defects at each visit. Fifty-five of these 120 (2% of the tested population) also exhibited some degree of disc cupping in a related eye at both visits. Among these 2%, positive associations relating the extent of field loss, cupping and intraocular pressure were confirmed, but the majority in each cupping category had normal eye pressures. Only seven of the 120 were aware of the presence or suspicion of eye disease prior to the screening. CONCLUSIONS: A majority of those found to have visual field loss and optic nerve cupping persisting together in the same eye after 3-5 years had normal pressures in each eye at both visits. Despite good access to medical care, very few who demonstrated persisting cupping and field loss (even among those with elevated eye pressure) were aware of their ocular condition through prior contact with an eye care professional.

Aged↗

[What do glaucomatous visual fields really look like?].

Analysis of the visual fields of 20 glaucoma patients using 229 F2 programmes consisting of 30 degrees long profiles with 1 degree resolution and double measurements of the light sensitivity threshold, revealed that there is a positive correlation between mean loss and mean short-term fluctuations; short-term fluctuations tend to be larger with increasing loss of sensitivity. However, small short-term fluctuations were also seen in areas of greatly reduced sensitivity. Analysis of the F2 programmes showed 12 different abnormal patterns. The pattern most frequently found, "increased scatter with normal sensitivity", appears to be the earliest perimetric sign of glaucoma. Progression of the glaucomatous damage produces a "gray area of increased scatter", usually accompanied by reduced sensitivity with a poorly defined lower and upper threshold.

Computers↗

Normal visual fields as assessed by computerized static threshold perimetry in patients with untreated primary hypothyroidism.

In this prospective study, 25 consecutive patients with untreated primary hypothyroidism were tested with a highly sensitive perimetric technique, since a high prevalence of visual field defects has been described in this condition. All patients had clinical hypothyroidism, a serum TSH value greater than 20 mU/l (reference range 0.4-4.0) and decreased/low normal serum total T4 concentration. Visual fields were tested with fully automated threshold-measuring computerized perimetry of the central 30 degrees field. Interpretation of fields included computer-assisted analysis provided by a perimetric statistical programme package. In 23 patients, conventional inspection and computer-assisted analysis showed no visual field defects. Two patients were excluded from the latter analysis: one patient who did not respond adequately at computerized perimetry and in whom manual field tests were entirely normal: one patient who had low sensitivity values in the uppermost parts of both visual fields owing to markedly swollen upper eye lids. In conclusion, although pituitary hyperplasia has been well documented in primary hypothyroidism, the present prospective study clearly indicates that visual field defects are not a common finding in patients with this disease.

Adult↗

The concept of visual field indices.

Statistical methods for the evaluation of quantitative visual fields are presented in addition to a mathematical description of the calculation of different visual field indices. The "mean defect" is important for diffuse damage as well as for follow-up in advanced stages. "Short-term fluctuation" provides information about the reliability of the results as well as about possible early damage. "Corrected loss variance" quantifies local defects in an early stage; it also separates real local defects from increased scatter. "Skewness" is a test for very early local defects, and "spatial correlation" provides a measurement of the clustering of any local defects that may be present.

Humans↗

Progression of visual field defects in glaucoma. Relation to compliance with pilocarpine therapy.

In patients with primary open-angle glaucoma, compliance with pilocarpine therapy was studied with an electronic medication monitor. The visual fields and intraocular pressure (IOP) readings were followed up retrospectively during two years before and two years after the compliance measurements. Progression of visual field defects was significantly more common in patients with capsular glaucoma than in patients with simple glaucoma. Eyes with more extensive visual field defects showed progression more often than did eyes with smaller defects, and so did eyes with a high mean IOP as compared with those with a low mean IOP. Visual field defect progression was not significantly more common among patients with "poor" than among patients with "good" compliance, which indicates that noncompliance is less important for the outcome than are the type of glaucoma, the stage of visual field defects, and the mean IOP.

Glaucoma, Open-Angle↗

The effect of hemodialysis on visual field test in patients with chronic renal failure.

PURPOSE: To investigate the visual field with FASTPAC 30-2 program before and after hemodialysis in patients with end stage renal disease. MATERIALS AND METHODS: Twenty eyes of 20 patients on regular hemodialysis were included in the study group. Twenty eyes of 20 healthy patients were chosen as control group. Intraocular pressures (IOP) were measured one hour before and one hour after the same hemodialysis session, and visual field was tested at the same times. RESULTS: When IOP was compared before and after hemodialysis, no statistically significant difference was found (p > 0.05), however Mean Deviation (MD) (p = 0.008) improved after hemodialysis. When we compared first global indices of the control group with pre-hemodialysis global indices, we noted significant difference in MD (p = 0.009). CONCLUSION: Visual field testing should be done after hemodialysis in patients who are on regular hemodialysis program.

Adult↗

Retrospective analysis of the surgically treated temporal lobe arteriovenous malformations with focus on the visual field defects and epilepsy.

BACKGROUND: Authors investigate the surgical outcomes of the temporal lobe arteriovenous malformation (AVM) with focus on the visual field deficit and seizure. METHODS: Between 1981 and 2004, we experienced 294 cases of intracranial AVMs. Among the 294 cases, 45 (15.3%) were located in the temporal lobe. Twenty-six of the 45 cases underwent microsurgical excisions of the AVMs. RESULTS: The male-female ratio of 26 surgically treated temporal lobe AVMs was 15:11. The mean age was 34.2 years, ranging from 7 to 63 years. The sites of lesion were classified as polar in 1, dorsal in 2, laterobasal in 15, and mediobasal in 8. The initial symptoms were hemorrhage in 22 and epilepsy in 4 cases. Arteriovenous malformations were totally removed in all 26 patients and there was no surgical mortality. The visual field deficits were identified in 17 of 22 patients with hemorrhage. Massive hematoma cases that needed emergency operation were 5. Visual field deficits improved in only 2 of the 5 patients after surgery. Among the 7 quadrantanopia patients, 3 resulted in hemianopia after surgery. Seven of 22 hemorrhage patients had history of epilepsy. Although one patient had new postoperative epilepsy, the medical controls of the seizure were good in all 8 patients. Four patients underwent AVM excision for epilepsy without hemorrhage. In two patients, seizures disappeared after surgery. The other two patients had typical psychomotor seizures after the total excision of AVMs. CONCLUSIONS: Improvement of visual field deficit due to hematoma was difficult in most cases. Emergency craniotomy for global neurological deterioration due to massive hematoma had improved the visual field deficit in two cases. Although the outcome of seizure associated with hemorrhage was acceptable, the postoperative intractable seizures would remain in cases with epilepsy without hemorrhage. Intraoperative electrocorticography might be requisite for nonruptured temporal lobe AVM cases with epilepsy.

Adolescent↗

Visual field damage in normal-tension glaucoma patients with or without ischemic changes in cerebral magnetic resonance imaging.

PURPOSE: To compare the pattern of visual field damage between normal-tension glaucoma (NTG) patients with signs indicative of ischemic changes and those NTG patients without signs of ischemic changes, using brain magnetic resonance imaging (MRI), in a single center, cross-sectional study. METHODS: In 94 consecutive NTG patients who were younger than 61 years old, brain MRI images were obtained using fluid-attenuated inversion recovery pulse sequences. The presence of signs indicative of ischemic changes in brain MRI images was decided separately by two neuroradiologists masked to the diagnosis and stage of glaucoma. Visual field testing was performed using the 30-2 program of the Humphrey Visual Field Analyzer. Between the patients with signs indicative of ischemic changes in brain MRI (ischemic group) and those without MRI signs (nonischemic group), total deviation (TD) at each test point less the average of TDs of the 30-2 program ([TD - TD(mean)])--was compared at each test point. RESULTS: Signs indicative of ischemic changes in brain MRI were found in 32 of the 94 patients (34.0%). Age, blood pressure, refraction, intraocular pressure, the average of TDs, mean deviation, and corrected pattern standard deviation were not significantly different between the ischemic (N = 32) and nonischemic (N = 62) groups (P > 0.2). [TD - TD(mean)] in the ischemic group was significantly smaller than that in the nonischemic group at 6 nonedge contiguous test points in the inferior pericentral to nasal field (P = 0.005-0.047). CONCLUSION: NTG patients with signs indicative of ischemic changes in brain MRI had a relatively deeper depression in the inferior pericentral visual field.

Blood Pressure↗

Visual field defects detected in patients with Gilles de la Tourette syndrome: preliminary report.

The presence of visual field anomalies was measured using Goldmann kinetic perimetry in twelve patients, age 7 to 39 with Gilles de la Tourette syndrome. Refraction to the cupola was carefully controlled. The visual acuity of the group was good to excellent. Visual field alterations were prechiasmal, generally non-symmetric, and best described as arcuate defects, steps, baring of the blind spot and enlargement of the blind spot. Central fields were most commonly affected, i.e., I/2e to I/1B isopters. There was no evidence of glaucoma in any of the patients although two patients exhibited keratoconus and another one manifested moderate to high astigmatism. Visual involvement other than ocular and lid tics have not been reported in Tourette syndrome. This research represents clear evidence of additional physical components in this condition. Automated visual field measurements are not recommended in this population because of the presence of non-predictable tic and vocal behavior (both may result in head/eye movements). Suppression of tic behavior can be very fatiguing. (Eight of twelve of the patients reported exhibited signs of marked fatigue during testing.)

Adolescent↗

Retinotopic organization of primary visual cortex in glaucoma: Comparing fMRI measurements of cortical function with visual field loss.

Primary open angle glaucoma (POAG) is a progressive optic neuropathy characterized by retinal ganglion cell loss. Experimental primate glaucoma indicates neuronal degeneration of the lateral geniculate nucleus (LGN) and activity changes in the visual cortex (V1). Neuronal degeneration has also been shown in a post-mortem human study of the optic nerve, LGN and visual cortex. Functional magnetic resonance imaging (fMRI), a non-invasive means of inferring function-specific neuronal activity, provides an opportunity to evaluate glaucomatous changes in neuronal activity throughout the visual pathway in vivo. The purpose of this study is to demonstrate that the relationship between visual field loss in human POAG and the functional organization of V1 can be measured using novel fMRI analysis methods. Visual field defects were measured using standard automated perimetry (SAP). A retinotopic map of visual space was obtained for V1, and the retinotopy data was fit with a template. The template was used to project regions within the visual field onto a flattened representation of V1. Viewing through the glaucomatous vs. fellow eye was compared by alternately presenting each eye with a scotoma-mapping stimulus. The resulting blood oxygen level dependent (BOLD) fMRI response was compared to interocular differences in thresholds for corresponding regions of the visual field. The spatial pattern of activity observed in the flattened representation agreed with the pattern of visual field loss. Furthermore, the amplitude of the BOLD response was correlated on a pointwise basis with the difference in sensitivity thresholds between the glaucomatous and fellow eyes (r = 0.53, p < 0.0001). The BOLD signal in human V1 is altered for POAG patients in a manner consistent with the loss of visual function. FMRI of visual brain areas is a potential means for quantifying glaucomatous changes in neuronal activity. This should enhance our understanding of glaucoma, and could lead to new diagnostic techniques and therapies.

Animals↗

Visual field asymmetries in numerical size comparisons of digits, words, and signs.

Visual field asymmetries were examined in American Sign Language-English bilinguals for speeded numerical size judgments of pairs of digits, number words, and number signs. Physical size of the number pairs was either congruent or incongruent with their numerical size. The results revealed a greater left visual field (LVF) interference for numbers represented as digits and a greater right visual field (RVF) interference for numbers represented as words or signs. Subjects' performance on number words and signs was also influenced by their skill in English and ASL: interference was greater in the RVF in the subjects' better language but was greater in the LVF for the less skilled language. These findings suggest that lateralization of numerical size judgments is moderated by the mode of number presentation and by prior language experience.

Adult↗