PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Visual Field Tests”

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 109 records · Page 6Linked to original sources

[Activity of neurons of the somatosensory and visual cortex in the rabbit during visual field testing and performance of food-getting behavior].

The activity of somatosensory and visual cortex neurons was compared in experiments on freely moving rabbits during testing of their receptive field and during natural "stimulation" of the receptive areas by environmental objects in food-acquisition behaviour. It was found that the neuronal activity during the receptive field testing may correspond completely, partly or not at all to that in food-acquisition behaviour, i.e. units displaying a certain relation to a receptive field area during the testing may keep it unaltered, alter it or lose it in food-acquisition behaviour. The different activity in the behaviour was observed even in neurons having identical receptive fields during testing. A conclusion is made that the picture of unit activity in the active goal-directed behaviour being modelled on the basis of receptive field testing may be rather vague. The results of experiments with the receptive field testing may help to develop the concept of processing of information about environment in the behaviour but with some limitations whose formulation demands special investigations.

Animals↗

Scotomas of age-related macular degeneration detected and characterized by means of a novel three-dimensional computer-automated visual field test.

PURPOSE: We used the recently devised three-dimensional computer-based threshold Amsler grid test to acquire and identify typical patterns of visual field defects (scotomas) caused by age-related macular degeneration (AMD). METHODS: Patients with AMD traced on a computer touch screen the borders of those areas on an Amsler grid that were missing from their field of vision. Scotomas were repeatedly outlined and recorded at different grid contrast levels. The resulting three-dimensional "hole" in the central 25 degrees of the visual field was further characterized by its slope, location, shape, and depth. The results were compared with fundus photographs and fluorescein angiograms. RESULTS: Twenty-five patients and 41 eyes were examined. The three-dimensional depictions consistently demonstrated central scotomas with "scallop"-shaped borders and steplike patterns, with either steep slopes or a combination of steep and shallow slopes. The steep slopes corresponded to nonexudative AMD, while the shallow slopes indicated exudative AMD. CONCLUSION: The three-dimensional computer-automated threshold Amsler grid test may demonstrate characteristic scotoma patterns in patients with AMD that conform to the respective fluorescein angiograms. The test shows promise as an effective tool in accurately evaluating, characterizing, and monitoring scotomas in patients with AMD. It may have the potential as a screening tool for the early diagnosis of AMD.

Aged↗

The influence of visual field testing procedure on blind spot size.

Blind spots as measured by three different testing instruments were shown to be significantly different. These size variations seem to be related to the target contrast provided by the instrumentation. The need for instrument standardization in perimetry is discussed.

Adult↗

Baseline visual field characteristics in the ocular hypertension treatment study.

PURPOSE: The Ocular Hypertension Treatment Study (OHTS) seeks to evaluate the safety and efficacy of topical ocular hypotensive medication in preventing or delaying the onset of visual field loss and/or optic nerve damage in ocular hypertensive subjects at risk for developing primary open-angle glaucoma. This study evaluates the baseline visual field test characteristics (visual field status, reliability properties, etc.) of patients who underwent eligibility visual field testing for entry to the OHTS. DESIGN: Cross-sectional study of baseline data as part of a longitudinal randomized clinical trial. PARTICIPANTS: Two thousand eight hundred nineteen ocular hypertensive individuals, aged 40 to 80 (mean age, 55). METHODS: Subjects underwent at least two Humphrey Field Analyzer Program 30-2 Full Threshold visual field examinations in both eyes for study eligibility. A third examination was performed if a prior test was abnormal, questionable, or unreliable. For final eligibility, two sets of visual field examinations had to meet OHTS criteria for reliability and had to be classified as "normal." All OHTS visual field tests of potential subjects were submitted for eligibility assessment to the OHTS Visual Field Reading Center. MAIN OUTCOME MEASURES: The percentage of visual fields that were normal and reliable according to OHTS criteria. RESULTS: Of the subset of 2304 subjects who completed the eligibility assessments, 1828 (79%) were OHTS-eligible based on visual field test requirements. A third eligibility test was required for 11% of all eyes because of unreliable, questionable, or abnormal test results. With the 33% fixation loss cutoff in the OHTS, 97% of all eligibility visual field examinations were reliable and 3% were unreliable. The most frequent cause (69.5%) of unreliability was excessive fixation losses. CONCLUSIONS: Permitting one repeat test after an abnormal or unreliable test allowed an extra 560 patients to be "eligible" for the study based on visual field tests. A clinical screening review of otherwise normal and reliable tests was not restrictive. The adoption of a 33% fixation loss cutoff significantly reduced the number of required retests and prevented study rejection of 89 patients.

Adult↗

Three-dimensional computer-automated threshold Amsler grid test.

We describe a novel method for testing a visual field that employs a computer monitor with displays of varying contrast that permits unprecedented resolution and characterization of the structure of scotomas in three dimensions. Patients are placed in front of a touch-sensitive computer screen at a fixed distance. With one eye covered, they focus on a central fixation marker and trace with their finger the areas on an Amsler grid that are missing from their field of vision. Increasing degrees of contrast of the Amsler grid are simulated by repeating the test at different gray-scale levels. The results are recorded and then displayed as topographical contour rings by the computer test program. The results can also be rendered as an immediate 3-D depiction of the central hill-of-vision. Several clinical pilot studies have been conducted at the Doheny Eye Institute and more than 200 patients have been examined with this system so far. Conditions such as optic neuritis, anterior ischemic optic neuropathy (AION), age-related macular degeneration (AMD), glaucoma, and ocular hypertension have been successfully assessed by this test. Each condition provides unique patterns that are most evident in 3-D. The 3-D computer-automated threshold Amsler grid test is an innovative and noninvasive visual field test. It provides several advantages over state-of-the-art standard automated perimetry, including: (1) additional information through 3-D depiction of scotomas, such as location, extent, slope, depth, and shape; (2) high angular resolution (1 deg compared with typically 6 deg); (3) a simple test setup (merely a touch-sensitive computer monitor and the test software); (4) excellent patient compliance (spending 4 to 5 min per eye). In light of its promising initial tests, the 3-D visual field test appears to have the potential for the early detection and monitoring of various diseases over time.

Diagnosis, Computer-Assisted↗

A practical approach to measuring the visual field component of fitness to drive.

AIMS: To determine the level of agreement between merged monocular visual field tests (the integrated visual field) and the binocular Esterman visual field test in classifying patients' visual status for UK legal fitness to drive. To examine the link between these two tests and the useful field of view (UFOV) test, a test which is considered to be a surrogate for the visual capability for safe driving. METHODS: Primary open angle glaucoma patients with bilateral overlapping visual field defects were recruited prospectively. Patients performed the bilateral monocular field tests (to generate the integrated visual field), the Esterman test and the UFOV test on the same visit. Patients were classified as "pass" or "fail" by both the integrated visual field and the Esterman test. UFOV risk scores were calculated for each patient. RESULTS: 65 patients were recruited. Substantial agreement was found between the integrated visual field and the Esterman test in classifying patients as "pass" or "fail" (kappa = 0.69). No patients classified as "pass" by the integrated visual field test were classified as "fail" by the Esterman test. Eight patients who were classified as "pass" by the Esterman test were classified as "fail" by the integrated visual field test. The UFOV risk characteristics of these eight patients suggested they were more similar to those of the 13 patients who were classified as "fail" by both the tests, than the 44 patients who were classified as "pass" by both tests. CONCLUSIONS: The integrated visual field test agrees well with the current method (Esterman) of classifying visual fields with regard to legal fitness to drive in the United Kingdom in patients with glaucoma; it appears superior to the current method in identifying those with reduced fitness to drive as measured by the UFOV. The integrated visual field test could perform a valuable screening or diagnostic role in the assessment of glaucoma patients' fitness to drive.

Adult↗

A comparison of the OKP visual field screening test with the Humphrey field analyser.

In order to determine the loss of retinal sensitivity detectable by oculokinetic perimetry (OKP), we tested 27 eyes of 27 persons with glaucoma and 32 eyes of 32 patients with ocular hypertension with the OKP screener and with a central threshold test on the Humphrey analyser. The threshold at eight locations on the OKP chart between 12.5 degrees and 15 degrees from fixation was compared with the corresponding Humphrey perimetric thresholds. Seventeen eyes from 17 patients with glaucoma failed the OKP screening test by not seeing the target at one or more locations. The mean light sensitivity threshold at points seen on OKP screening was -5.8 dB (SD 4.6 dB) from aged-matched normals (AMN), whereas points missed had a mean threshold -16.1 dB (SD 9.3 dB) from AMN. The sensitivity and specificity with which OKP testing differentiated normal points from abnormal ones in Humphrey testing was 82.5% and 80% respectively, with a threshold criterion of -12 dB from AMN. Ten eyes from 10 patients with glaucomatous defects and all of the ocular hypertensive eyes gave normal responses on the OKP screening test. The glaucomatous eyes that passed were characterized by less severe defects on the Humphrey than those who failed in terms of mean deviation (0.02 < p < 0.05) or corrected pattern standard deviation (0.01 < p < 0.02). Four of the glaucomatous eyes to pass had a nasal step as the primary field defect. None of those to fail failed only on points within 10 degrees of fixation. We suggest further modification of the OKP screening chart to improve its efficiency.

Fixation, Ocular↗

Comparison of pattern visual-evoked potentials to perimetry in the detection of visual loss in children with optic pathway gliomas.

PURPOSE: We sought to compare visual evoked potentials (VEPs) with standard visual field testing in children with visual pathway gliomas. METHODS: Fifteen of 40 children with visual pathway gliomas verified on magnetic resonance imaging scan who cooperated with Goldmann visual field (GVF) and 3-channel VEPs were studied. GVFs were obtained in 25 eyes with adequate vision. VEP amplitudes, latencies, and signal-to-noise ratios (SNRs) were compared with control subjects. Four of the patients (5 eyes) also had Humphrey visual field testing. RESULTS: Twenty-two of 25 eyes had a field defect, 15 eyes showed a relative or absolute hemianopia, 7 eyes showed a central or generalized depression, and 3 eyes were normal. In hemianopic eyes, 87% showed a depression (GVF) or reduced sensitivity (Humphrey field) in the opposite hemifield. VEP amplitudes and SNRs, normally largest at the midline electrode, were significantly reduced in all eyes with visual field loss. By comparison, lateral electrodes showed significantly lower amplitudes and SNRs in patients and controls. Interhemispheric VEP asymmetry (>2:1 ratio) was seen in 67% of patients with hemianopia and 53% of controls. CONCLUSIONS: Reduction of amplitude and SNR at the midline VEP electrode was a sensitive indicator of visual field loss. Interhemispheric VEP asymmetry was not reliable in detection of a hemianopic field defect. VEPs can be a reliable and objective alternative for the detection of visual loss due to optic pathway glioma in children who are intolerant to visual field testing. We recommend the test protocol include pattern-onset and check reversal stimuli of at least one high and one low spatial frequency.

Adolescent↗

Analysis of progressive change in automated visual fields in glaucoma.

PURPOSE: To detect and estimate the rate of progression of visual field loss in subjects with glaucoma who undergo long-term automated perimetric visual field testing. METHODS: Automated visual field data were obtained for subjects with glaucomatous visual field loss and a minimum of seven threshold field tests over at least 4.5 years. Univariate linear regression was performed with respect to mean deviation (MD), corrected pattern standard deviation (CPSD), mean thresholds of clusters corresponding to the Glaucoma Hemifield Test (GHT), and thresholds of 52 individual test locations. Subjects were classified as progressive or stable (unchanged or improved) based on the slope and statistical significance of these parameters. Adjusted P values were used to maintain the overall type 1 error at 5%. RESULTS: One hundred ninety-one subjects with a mean follow-up period of 7.1 years (range, 4.5 to 10.5 years) and a mean number of visual field tests of 9.5 (range, 7 to 16) were included. Twenty-four subjects (12.6%) showed progression in MD (mean slope [95% confidence interval], -1.26 [-1.50, -1.01] dB/year), and 27 (14.1%) showed progression in CPSD (mean slope [95% confidence interval], 0.71 [0.58, 0.84] dB/year). Thirty-five subjects (18.3%) had > or = 1 progressive GHT cluster. The mean slope in progressive clusters ranged from -1.51 [-1.82, -1.20] to -2.84 [-3.39, -2.29] dB/year. Thirty-six subjects (18.8%) had > or = 1 progressive individual test locations. Fifty-two subjects (27.2%) were classified as progressive based on progression of CPSD, > or = 1 cluster and/or > or = 1 point. CONCLUSIONS: Fewer than 1 in 3 subjects progressed by any one of the criteria for progression over an average of 7.1 years. Rates of progression that could be statistically confirmed were in the range of approximately 1 to 5 dB/year, depending on the number of fields, the variability over time, and the parameter assessed (global indices, GHT clusters, or individual points). No correlation between initial visual field status and the rate of progression was found. A minimum of approximately 5 years of follow-up with annual perimetry would be required to detect significant changes in the visual field by linear regression.

Adolescent↗

Frequency doubling technology threshold testing in the pediatric age group.

PURPOSE: To evaluate the feasibility of performing visual field with the Frequency Doubling Technology (FDT) in children aged 5 to 10 years. PATIENTS AND METHODS: Forty healthy children and fifteen healthy adults, all with no previous experience with visual field testing, underwent visual field testing with the C20 threshold test of the Carl Zeiss Meditec FDT analyzer in both eyes. The subjects were divided into three groups. Group A (age 5-7), group B (age 8-10), and group C (adults). RESULTS: The mean explanation time for the test was 83 +/- 43 seconds for group A, 68 +/- 31 seconds for group B, and 37 +/- 15 seconds for group C (P < 0.001 for the difference between group C and groups A and B). Test performance time for the right eye was 347 +/- 57 seconds, 301 +/- 21 seconds, and 298 +/- 35 seconds for groups A to C, respectively (P < 0.001 for the difference between group A and groups B and C). Forty percent of the children, but none of the adults required two demonstrations prior to initiation of the test. In children fixation losses for the right and left eye were 10% and 37% respectively. No fixation losses occurred in adults. In both eyes a mean deviation <0.5% occurred significantly more often in group A than in group C (P = 0.013). CONCLUSION: Visual field testing with FDT in the young age group is feasible. Test reliability was similar between children aged 5 to 7 and 8 to 10. Pre-selection of children is suggested to achieve reliable results.

Adult↗

Static versus kinetic testing in the nasal peripheral field in patients with glaucoma.

One-hundred and seventy-seven subjects (207 eyes) were tested on the Humphrey Field Analyzer to evaluate the usefulness of static and kinetic peripheral nasal visual field testing in identifying glaucomatous defects. In 20 of the 187 glaucomatous or ocular hypertensive eyes glaucomatous defects were found in the peripheral nasal field while the central 30 degrees remained normal or showed non-specific diffuse depression. Kinetic peripheral nasal field testing identified 17 of these eyes while the static testing identified eleven. This difference was not statistically significant (P greater than 0.05, Stuart-Maxwell test). Twenty control eyes showed one glaucomatous peripheral nasal defect on static testing, and none with kinetic testing. These results differed statistically from the diagnoses in the diseased population (P less than 0.005, chi 2-test). This study suggests the potential value of nasal peripheral field testing in selected glaucoma patients for which static testing has no apparent diagnostic advantage over kinetic techniques.

Adolescent↗

Changes in retinal light sensitivity following blunt ocular trauma.

PURPOSE: To prospectively examine changes in retinal light sensitivity following blunt ocular trauma in eyes with traumatic hyphaema with no evidence of retinal injuries 1 week, 1 month and 4 months after injury. METHOD: Sixteen patients who sustained hyphaema after blunt ocular trauma without visible traumatic retinal lesions underwent visual field testing on the C 30-2 programme of the Humphrey field analyser as soon as visual acuity recovered to 0.7 or more with correction. RESULTS: Significant reduction in retinal sensitivity with MD (mean deviation) p values less than 5% was found in 50% (8 eyes) of our patients 1 week after injury. MD p values significantly improved 1 month after injury (p < 0.001) and even more so after 4 months (p < 0.00004). After 4 months only in one eye (6%) was a significant reduction in retinal sensitivity observed with a MD p value less than 5%. No correlations between improvement in retinal sensitivity and the extent of hyphaema or the extent of angle recession were observed. CONCLUSIONS: In 50% of eyes following blunt ocular trauma without evident traumatic posterior segment abnormalities significant transient reduction in retinal light sensitivity was observed with nearly complete recovery over time.

Adolescent↗

Blue versus white stimuli in ocular hypertension with the Friedmann Mark 1 Visual Field Analyser.

Fifty eyes of fifty patients with ocular hypertension had their visual fields tested on a Friedmann Mark 1 field analyser whilst wearing a Wratten 47B blue filter in a spectacle frame. All had normal visual fields to a white stimulus. Use of a scoring system with the blue field identified 11 patients (22%) with ocular hypertension as abnormal. The scores from this subgroup were indistinguishable from a group of subjects with early glaucomatous field loss, whilst the remaining scores were similar to normal subjects. These two subgroups of ocular hypertensive patients were similar in age and intraocular pressure. The use of a blue filter in front of the eye may offer a simple test to identify a subgroup of patients with ocular hypertension who are at increased risk of developing field loss.

Color↗