Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Visual Fields”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 1,783 records · Page 99Linked to original sources
PubMed2006

Pointwise linear regression analysis for detection of visual field progression with absolute versus corrected threshold sensitivities.

PURPOSE: To compare the performance of point-wise linear regression analysis (PLR) with total deviation (TD) versus corrected or pattern deviation (PD) threshold sensitivities for detection of visual field progression. METHODS: Four hundred two eyes (402 patients) enrolled in the Advanced Glaucoma Intervention Study (AGIS) were selected. Criteria for progression according to PLR were a slope or=2 worsening points within the same Glaucoma Hemifield Test cluster. PLR was performed on TD and PD threshold sensitivities and compared to clinical evaluation. Eyes were classified into three groups based on mean deviation (MD): mild (MD>or=-6 dB), moderately advanced (-6 dB>MD>or=-12 dB), and advanced (MD<-12 dB) glaucoma. RESULTS: Visual field progression was observed in 154 (38%), 85 (21%), and 175 (44%) eyes, according to PLR(TD) and PLR(PD), and clinical evaluation. The pair-wise agreement between clinicians and PLR(TD) was significantly greater than that of clinicians and PLR(PD) (kappa=0.48, 95% CI: 0.44-0.52 vs. kappa=0.31, 95% CI: 0.27-0.35). Agreement between PLR(TD) and PLR(PD) decreased with increasing glaucoma severity: kappa (95% CI)=0.60 (0.52-0.67), 0.41 (0.35-0.47), and 0.33 (0.27-0.40) for mild, moderately advanced, and advanced glaucoma, respectively. CONCLUSIONS: Point-wise linear regression analysis on TD threshold sensitivities performed better than the same analysis on PD when clinical evaluation was used as a reference. Agreement between the two methods was less in moderately advanced and advanced glaucoma.

Adult↗
PubMed1982

Tectal processing of visual signals from the caudalmost part of the frog visual field.

Electrophysiological investigations restricted to the caudomedial part of the optic tectum show that the caudalmost part of the frog's visual field appears preferentially analyzed by class-2 and class-3 retinal ganglion cells and integrated by monocular T5 neurons even though this spatial region is seen by the two eyes and doubly represented on each tectum. This apparent preponderance for three types of contralateral visual units is discussed on the basis of the animal's behaviour.

Animals↗
PubMed1986

Long- and short-term monocular deprivation in the rhesus monkey: effects on visual fields and optokinetic nystagmus.

Monkeys with 1 eyelid sutured within 2 weeks of birth for 7 or 14 d (short-term monocular deprivation, n = 5) or for 18-26 months (long-term monocular deprivation, n = 5) were tested for visual and oculomotor function at approximately 2 years of age. Long-term monocularly deprived animals were behaviorally blind when visual inputs were restricted to the deprived eye. There was no sparing of the monocular segment of the visual field, and optokinetic nystagmus could not be elicited even with vertical stripes up to 15 degrees in width. These behavioral deficits could not be accounted for by optical or retinal abnormalities. In contrast, short-term monocularly deprived animals displayed normal visual fields and optokinetic nystagmus was driven by both eyes. Slow-phase gain was reduced and directional asymmetries were observed when optokinetic stimulation was restricted to the deprived eye.

Animals↗
PubMed1993

[Blood-retinal barrier and visual field in retinitis pigmentosa].

The aim of the research was to determine, with new-generation fluorometer (Fluorotron Master), the factor of fluorescein leakage into the vitreous and to reveal, with the static perimeter (Humphrey's), the quantitative parameter of the visual field in retinal pigmentary dystrophy. The factor of fluorescein leakage into the vitreous was almost ten times higher in retinal pigmentary dystrophy and it indicated the damage of blood-retina barrier. The correlation between the factor of fluorescein leakage into the vitreous and the degree of visual field defect has not been found.

Adolescent↗
PubMed1988

The relationship between the fluoroangiographic aspect of the optic disk and the visual field in patients with the exfoliation syndrome with and without intraocular hypertension. Part II: Monolateral cases.

Patients with monolateral exfoliation syndrome were examined to elucidate the differences between the eye with the exfoliation and the fellow eye and to explain the damage of the visual field of the eyes with or without exfoliation. The greatest difference between the two groups of eyes is represented by an increased pigmentation of the anterior chamber angle. The visual field, as in bilateral cases, shows the greatest damage when exfoliation and hypertension are present together in the same eye. An hypothesis is put forward to explain the supposed mechanism of action of these two factors.

Aged↗
PubMed1989

Visual field change in low-tension glaucoma over a five-year follow-up.

There is some evidence that the nature and progression of disease in low-tension glaucoma may be distinct from other open-angle glaucomas. The authors assessed visual field change by retrospective case review of all patients treated for low-tension glaucoma by the Glaucoma Service, Wills Eye Hospital, for at least 5 years. Sixty-two glaucomatous eyes of 36 patients were identified. All eyes were treated medically and 40 (65%) underwent at least one surgical procedure. Twenty-eight eyes (47%) had initial field loss confined to a single hemi-field and in the remainder both hemi-fields were involved. Thirty of 57 eyes (53%) showed progression at 3 years and 38 (62%) of 57 had progressed by 5 years. A dense scotoma extending from the nasal periphery toward fixation was the most common visual field defect. The rate of field change in this population is significantly greater than in a cohort of primary open-angle glaucoma patients also seen at Wills Eye Hospital, but who had elevated intraocular pressures. Patterns of field loss and rate of progression in this low-tension glaucoma population suggest that the natural history of low-tension glaucoma differs from high-tension open-angle glaucoma.

Aged↗
PubMed1993

Visual field loss secondary to radiation-induced cerebral necrosis.

Radiation-induced cerebral necrosis has been well documented in the literature. Because radiation induced cerebral necrosis can occur to any part of the central nervous system that falls within the irradiated area, the visual pathway is highly susceptible to damage as it passes from the eye to the visual cortex. With proper visual field testing and interpretation, optometrists may serve as primary diagnosticians in radiation-induced cerebral necrosis and actively participate in the long-term management of these patients. This case presents a patient with visual field loss secondary to a temporal lobe lesion whose etiology was thought to be radiation-induced. The incidence, pathophysiology, and clinical features of radiation-induced cerebral necrosis as well as other differential diagnoses are discussed.

Aged↗
PubMed1977

Rapid deterioration of visual fields during bromocriptine-induced pregnancy in a patient with a pituitary adenoma.

A 28-year-old woman with an amenorrhoea-galactorrhoea syndrome was suspected of a microadenoma of the pituitary. She was treated with bromocriptine. In the subsequent pregnancy she developed rapid deterioration of the visual fields (ODS). A large temporal defect in the right eye and a moderate temporal defect in the left eye appeared in the 28th week of pregnancy, threatening the visual acuity of both eyes. Other examinations showed no evident lesion of the sellar region. An adenoma of the pituitary was removed, and the visual fields returned to normal after operation.

Adenoma↗
PubMed1986

Determinants of the enhancement of the right visual field advantage by bilateral vs. unilateral stimuli.

Bilateral presentation of two different verbal inputs usually produces a stronger left hemispheric/right visual field (RVF) processing advantage than unilateral presentation. Previous reports of this effect confounded stimulus load with display configuration. Two experiments are presented in which the number of items during unilateral and bilateral trials was equated. The RVF advantage was enhanced during a free recall paradigm (Experiment I) but not during a partial report paradigm in which subjects were cued in advance to report only the top or the bottom of the display (Experiment II). This demonstrates that the effect does not depend upon the number of inputs per display and can not invariably be produced by bilateral/bihemispheric stimulation. It is suggested that subjects may be strongly biased to give priority to items delivered to the RVF/left hemisphere during bilateral trials. However, when this bias is constrained by rendering half of the RVF inputs irrelevant, subjects may be forced to pay equal attention to LVF inputs. Thus, eliminating the attentional bias eliminates the enhancement of the RVF advantage during bilateral trials.

Adolescent↗
PubMedDate not supplied

Foggy visual field defect.

A 32-year-old female migraneur developed a right incongruous homonymous hemianopia after taking the antiepileptic agent, topiramate. The visual field defect partially resolved when the medication was discontinued. The differential diagnosis of the homonymous hemianopia is discussed.

Adult↗
PubMed2000

Search for an optimal combination of structural and functional parameters for the diagnosis of glaucoma. Multivariate analysis of confocal scanning laser tomograph, blue-on-yellow visual field and retinal nerve fiber layer data.

BACKGROUND: The purpose of this study was to evaluate which of the structural and functional parameters--the Heidelberg Retina Tomograph (HRT), white-on-white (W/W) and blue-on-yellow (B/Y) visual fields and semiquantitative retinal nerve fiber layer (RNFL) scoring parameters--can give the best separation between non-glaucomatous and glaucomatous eyes. METHODS: Fifty-five subjects were included in this study: 32 nonglaucomatous subjects with mean age of 54 years, and 23 patients with ocular hypertension or glaucoma and mean age of 59 years. The HRT with software 1.11, the Humphrey 30-2 W/W and lens coloration-corrected B/Y visual fields, and semiquantitative RNFL scores were utilized. Stepwise logistic regression analysis was used in finding, from a given set of parameters, a best discriminating parsimonious subset to a logistic model, the discriminatory performance of which was evaluated by the area under the ROC curve. RESULTS: When all the structural and functional variables were considered, the RNFL total overall score gave the best separation between glaucomatous and non-glaucomatous eyes (ROC area 0.98). Without the RNFL scores and optic disc size-dependent HRT parameters in the model, the cup shape measure was selected first (ROC area 0.88). In the second step the RNFL thickness was selected (ROC area 0.91), and in the third step the corrected B/Y mean deviation (MD) was selected (ROC area 0.91). With only the HRT parameters in the model, the cup/disc ratio was selected first (ROC area 0.88). However, when the groups were matched for optic disc size, all disc size-dependent HRT variables lost their discriminant power. CONCLUSION: Cup shape measure and RNFL thickness, together with age- and lens coloration-corrected MD of the B/Y perimetry provided good discrimination between healthy individuals and patients with glaucoma.

Adult↗
PubMed1994

[18p-syndrome with bilateral pyramidal tract signs, dystonia of the lower extremities and concentric visual field defect].

A case, diagnosed as 18p-syndrome by typical clinical appearance and by chromosomal analysis, presented with multiple nervous system defects consisting of bilateral pyramidal tract signs, weakness and focal dystonia of the lower extremities, and concentric visual field defect. Chromosomal analysis revealed karyotype 46, X, dic (Y;18) (p11;p11), inv(9) (p11q13), and the points of chromosomal breakages were thought to be in the short arm of chromosome 18 and in the short arm of Y chromosome. 18p-syndrome is caused by a chromosomal deletion, and presents with a wide variety of clinical appearances. Many cases have been reported since the original descriptions by de Grouchy in 1963, though with few mentions of neurological deficits other than mental retardation. Furthermore, there have been no reports of pyramidal tract signs, weakness and focal dystonia of the lower extremities, or visual field defect, without recognizable anatomical abnormalities. Our case of 18p-syndrome is quite rare because of multiple nervous system abnormalities mentioned above, not accompanied by malformations of the central nervous system.

Adult↗
PubMed1977

The visual field of low tension glaucoma and shock-induced optic neuropathy.

The visual fields of patients with shock-induced optic neuropathy with excavation, low tension glaucoma, and chronic simple glaucoma were analyzed. True altitudinal defects are seldom found. The three disease states showed identical field defects. Subtle defects can occur in all three disease states. The preponderance of defects occurred in the upper field. There are obvious differences from ischemic optic neuropathy.

Chronic Disease↗
PubMed1979

Modifications of the pattern-evoked potential (PEP) in relation to the stimulated part of the visual field (clues for the most probable origin of each component).

A spatio-temporal analysis of the successive and simultaneous components of the pattern-evoked potential recorded on the scalp, and of their modifications according to which part of the visual field is stimulated, was carried out with 20 'normal' subjects, in order to shed some light on their most probable sites of origin. The stimulus consisted in the onset of a 20 degree checkerboard presented in runs of 75 stimuli each. Its duration was 750 msec and its frequency of occurrence was random (about 1 every 1500 msec). Twelve different visual field situations were recorded: whole field, half fields and quadrants and stimuli limited to the fovea, to the macula and to extramacular areas. Data were collected from 9 active electrodes (in line, forming a cross montage), and various reference electrodes (ear lobes, Fz, non-cephalic). Eye movements were simultaneously recorded. The electrophysiological data were digitized on line and processed by computer in the form of averaged spatio-temporal maps. In addition to the classical posterior components which peak on the midline (N 60, N 140, and P 200) or less than 4 cm away on both sides (P 90), a late negative wave (LN 210) was differentiated which peaked lower than the inion and more than 8 cm away from the midline on both hemispheres. The large inter-individual variability of the spatio-temporal organization of these components under the same conditions, as well as its very good intra-individual reproducibility, were emphasized. Interpreted on the basis of a simple dipole sheet model of the visual cortex, the changes observed for each component in the 12 experimental situations led to the following suggestions: only the first component N 60 could reflect the activity of the part of area 17 emerging on the convexity, whereas P 90 (Jeffreys' CI) is more likely to originate in area 19 and the midline components N 140 and P 200 in area 18. The topography and reactivity of LN 210 could fit with the hypothesis that it reflects activity of the infero-temporal cortex.

Adult↗
PubMed1994

Effects of typeface characteristics on visual field asymmetries for letter identification in children and adults.

The current study compared the effects of three typeface characteristics (script-likeness, or resemblance to cursive writing; confusability, or likelihood of confusing one letter with another; and difficulty, as indexed by naming latency) on letter identification in a divided visual fields test. It also asked whether and how these effects change with subject age. Subjects were 48 right-handed 9- and 14-year-old boys and undergraduate men--16 in each age group. They orally identified single letters in eight different typefaces presented tachistoscopically to the left or right visual hemifield. The difference between hemifields in threshold presentation time was the dependent measure. For all ages, the direction and degree of the visual field advantage changed with typeface complexity (a composite index of the three characteristics), with the simplest typeface yielding a right visual field/left hemisphere advantage, and with two of the most complex typefaces yielding a left visual field/right hemisphere advantage. There were age differences, though, in the relative contribution of the individual characteristics to this effect. For undergraduates, the strongest predictor of right hemisphere participation was script-likeness, whereas for 9- and 14-year-olds it was typeface difficulty.

Adolescent↗
PubMed1990

Hemianopic offsets in the visual field of patients with glaucoma.

In 359 glaucoma patients (600 eyes), we measured the peripheral field with kinetic targets and the central 30 degrees field of vision with static testing, using the Field-master-5000 automated perimeter to evaluate the prevalence and significance of step-like visual-field defects along the vertical midline (a hemianopic offset). In all, 129 eyes of 121 patients had a hemianopic offset. In 108 eyes the offsets (involving either the peripheral or the central field or both) were associated with other glaucomatous field changes, whereas 21 eyes showed a peripheral offset as an isolated finding. Of the 8 cases of offsets found in both eyes, 7 were binasal and 1 occurred bitemporally but in separate hemifields. This study suggest that hemianopic offsets occur commonly in glaucoma patients but have limited diagnostic value because most are associated with other glaucomatous field changes. However, these findings help in distinguishing glaucomatous offsets from those caused by neurological lesions.

Glaucoma↗
PubMed1998

Use of bioptic amorphic lenses to expand the visual field in patients with peripheral loss.

PURPOSE: To test the effectiveness of a bioptic form of a peripheral vision-enhancement lens in patients with retinitis pigmentosa (RP), choroideremia, and Usher's syndrome Type II. METHODS: Fifteen patients with peripheral visual field loss were trained in the use of the amorphic lenses for driving and other everyday activities for a 3-month period. A cross-over study design was used, where one group of eight patients received training during the first 3 months of the 6-month study, and another group of seven patients received training during the second 3 months. All patients were administered a battery of clinical, psychophysical, functional, mobility, and driving assessment tests at the beginning of the study, at 3 months, and at 6 months. The assessment tests were coded according to the primary visual skill involved in the task. These visual skills included: recognition, peripheral detection, scanning, tracking, visual memory, and mobility. RESULTS: After training, the patients showed improvement in all visual skills categories on the assessment tests, with overall improvement of 37%. There was no significant difference in the levels of improvement between the two groups. Those with smaller visual field extents showed significantly greater improvement on peripheral detection and scanning tasks. Those patients trained during the first 3 months of the study maintained their skills when tested at the 6-month point. CONCLUSION: Patients with peripheral vision loss may benefit from a rehabilitation program which combines low vision training with amorphic lenses in a bioptic configuration.

Adult↗