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Optometry (St. Louis, Mo.) Jun 2011
Topics: Brain Injuries; Cognition Disorders; Humans; Vision Disorders; Vision Tests
PubMed: 21616461
DOI: 10.1016/j.optm.2011.03.006 -
Optometry and Vision Science : Official... Sep 1995BACKGROUND. Our purpose is to develop a clinical test capable of assessing vision through dense cataracts (and other advanced media opacities) before surgery. Because... (Clinical Trial)
Clinical Trial
Hyperacuity test to evaluate vision through dense cataracts; research preliminary to a clinical study. II. Initial trials of the India instrument and HASP protocol at Aravind Eye Hospital, Madurai, India.
BACKGROUND. Our purpose is to develop a clinical test capable of assessing vision through dense cataracts (and other advanced media opacities) before surgery. Because such anomalies are endemic in the developing world, it was desirable to conduct a clinical study of a prototype India instrument and HyperAcuity Study Protocol (HASP) in such a setting. This investigation, preliminary to a planned clinical study, was conducted at the Aravind (Free) Eye Hospital, Madurai, India. EXPERIMENTAL. The preliminary HASP protocol, developed in Berkeley, was adapted to existing clinical practices in Madurai. Included was a new test of visual acuity, the Gap "VA" test, developed as part of the revised protocol. The rational for this test, methods used, and sample data are presented. A Vernier alignment test (one of the hyperacuities) is used to assess vision through dense ocular media disorders. The task of the patient is to align vertically three high luminance, discrete visual stimuli. The revised HASP protocol and adapted India instrument were tested upon patients with advanced cataracts. The cataract grading system used in these studies (provided by Drs. N. V. Projna and G. Rohini) is defined. Patients were tested before and shortly after surgery. This investigation allowed us to refine the test protocol and instrument design preparatory for a clinical study of HASP. A much simpler/cheaper version of the India instrument will be used in the planned clinical study. Additional experiments are scheduled in order to address issues which require resolution before initiation of next-stage testing. In part, in these papers, we seek to help others understand some problems encountered when conducting research in a developing world environment, even a very good one!
Topics: Aged; Cataract; Clinical Protocols; Developing Countries; Humans; India; Vision Disorders; Vision Tests; Visual Acuity
PubMed: 8532304
DOI: 10.1097/00006324-199509000-00006 -
Journal Francais D'ophtalmologie Dec 2001To evaluate the accuracy of the Bébé-Vision test for detecting strabismic, ametropic and anisometropic amblyopia in childhood.
PURPOSE
To evaluate the accuracy of the Bébé-Vision test for detecting strabismic, ametropic and anisometropic amblyopia in childhood.
METHODS
We screened 199 infants under 20 months of age. The screening consisted of a full orthoptic examination by a trained orthopist (cover test, fixation test), a forced choice preferential looking technique (Bébé-Vision test) prior to cycloplegia to test visual acuity, cycloplegic refraction by retinoscopy, and examination of the fundi.
RESULTS
Fifteen infants were abnormal on orthoptic examination (clinical evidence of esotropia and/or limitation of abduction and/or amblyopia). The Bébé-Vision test demonstrated a significant interocular difference on the same side of the suspected amblyopic eye in 3 cases and on the opposite side in 3 cases, and no difference in 9 cases. The monocular Bébé-Vision test was abnormal in 51 cases and there was an abnormal cycloplegic refraction in 33 cases. Statistical analysis of these tests demonstrated a very low sensitivity (42%) and a good specificity (90%) for the Bébé-Vision test in detecting amblyopia related to refractive error.
CONCLUSION
The Bébé-Vision test does not reliably reveal strabismic or anisometropic amblyopia and is not recommended as a screening test. Diagnosis should continue to be based mainly on the classical clinical methods.
Topics: Amblyopia; Female; Humans; Infant; Male; Mass Screening; Strabismus; Vision Tests
PubMed: 11913232
DOI: No ID Found -
Spatial Vision 1997Anti-aliasing is a technique for improving spatial resolution at the cost of luminance resolution. Dithering is a technique for improving luminance resolution at the... (Review)
Review
Anti-aliasing is a technique for improving spatial resolution at the cost of luminance resolution. Dithering is a technique for improving luminance resolution at the cost of spatial resolution. These techniques are applied to the testing of visual function in the 'Freiburg Visual Acuity Test': by employing anti-aliasing, spatial resolution was improved. Thus, even the shape of small Landolt-Cs with oblique gaps is adequate, and visual acuities from 5/80 (0.06) up to 5/1.4 (3.6) can be tested at a distance of 5 m. By employing dithering, subthreshold contrast stimuli can be generated on a conventional display having standard 8-bit video resolution. Rapid acquisition of a semi-objective and reliable acuity estimate makes the 'Freiburg Visual Acuity Test' useful for subject screening in vision research, as well as for routine assessments in the ophthalmic practice.
Topics: Computer Terminals; Humans; Microcomputers; Software; Vision Tests; Visual Acuity
PubMed: 9304755
DOI: 10.1163/156856897x00087 -
Ophthalmology Sep 1999The effect of chloroquine toxicity on color vision is unclear. The authors identified the color defects seen in chloroquine retinopathy and determined the sensitivity...
OBJECTIVE
The effect of chloroquine toxicity on color vision is unclear. The authors identified the color defects seen in chloroquine retinopathy and determined the sensitivity and specificity of clinical color vision tests for detecting the presence of previously diagnosed chloroquine retinopathy.
DESIGN
Case-control study.
PARTICIPANTS
Chloroquine retinopathy was defined using previously published criteria. Data from 30 patients with retinopathy and 25 patients using chloroquine but with no evidence of retinal toxicity were collected.
METHODS
All patients were tested with the following six clinical color vision tests: Ishihara, Farnsworth D-15, and Adams Desaturated-15 (Dsat-15), City University 2nd Edition (CU), Standard Pseudoisochromatic Plates Part 2 (SPP-2), and American Optical Hardy Rand Rittler (AO HRR).
MAIN OUTCOME MEASURES
The number of failures was determined for each test. The types of color vision defects were classified as blue-yellow (BY), red-green (RG), or mixed RG and BY (mixed).
RESULTS
Of the 30 patients with retinopathy, 28 (93.3%) of 30 patients failed at least 1 color vision test, demonstrating predominantly mixed defects. Five (25%) of 25 of the control subjects failed at least 1 test, and these defects were predominantly BY. The sensitivity and specificity of the tests are as follows: SPP-2 (93.3%, 88%), AO HRR (76.7%, 88%), Ishihara (43.3%, 96%), Dsat-15 (33.3%, 84%), D-15 (16.7%, 96%), and CU (20%, 92%).
CONCLUSIONS
Color vision can be affected by chloroquine and should be tested routinely with a color vision test designed to detect both mild BY and protan RG defects to maximize sensitivity for toxicity. The SPP-2 and AO HRR are two tests that meet these criteria. The Ishihara has a low sensitivity, as do the D-15 tests and CU. All of the tests have similar specificity for chloroquine toxicity. If color vision defects are detected in patients at risk of developing chloroquine retinopathy, additional testing is indicated to rule out toxicity.
Topics: Adult; Aged; Aged, 80 and over; Antimalarials; Case-Control Studies; Chloroquine; Color Perception Tests; Color Vision Defects; Female; Humans; Male; Middle Aged; Retina; Retinal Diseases; Sensitivity and Specificity; Visual Acuity
PubMed: 10485553
DOI: 10.1016/S0161-6420(99)90338-X -
Current Opinion in Ophthalmology Feb 1992Clinical accommodation tests can theoretically be categorized into five different types: 1) tests of accommodative amplitude, 2) tests of relative accommodation, 3)... (Review)
Review
Clinical accommodation tests can theoretically be categorized into five different types: 1) tests of accommodative amplitude, 2) tests of relative accommodation, 3) tests of accommodative facility, 4) tests measuring lag of accommodation, and 5) tests finding the dioptric accommodative stimulus at which dioptric stimulus and response levels are equal. Studies of the interrelation of accommodation tests indicate that a complete evaluation of accommodative disorders in nonpresbyopes should include at least one test from four of the five categories. Measurements of accommodative amplitude, lag, and facility, and relative accommodation should be included. Results from the fifth type of test listed above correlate well with lag of accommodation. Recent research is bringing greater acceptance and standardization to accommodative facility testing.
Topics: Accommodation, Ocular; Humans; Vision Tests
PubMed: 10149307
DOI: 10.1097/00055735-199202000-00011 -
Der Ophthalmologe : Zeitschrift Der... Mar 2004Screening tests of visual functions using the Internet are theoretically possible. To use these tests as a screening test, they must deliver comparable results with... (Comparative Study)
Comparative Study
BACKGROUND
Screening tests of visual functions using the Internet are theoretically possible. To use these tests as a screening test, they must deliver comparable results with conventional test procedures. A web-based color vision test was developed based on pseudoisochromatic color plates.
METHOD
The web-based color vision test was developed according to the pseudoisochromatic color plates by Velhagen and Broschmann using the programming-languages HTML, Java, and Perl. Sixty-five voluntary subjects, including nine color-deficient subjects, were examined by luminescence color plates (via web-based color vision test) and pigment color plates (via book). The statistical analysis was performed by determining the correspondence and the 95%-confidence interval.
RESULTS
The correspondence of the test results for all subjects was 0.98 and the 95%-confidence interval was within 0.91 and 0.99. The correspondence of the test results in the group of color-deficient subjects was 1.0 and because of the limited number the 95%-confidence interval was within 0.71 and 1.0.
CONCLUSIONS
The web-based color vision test with luminescence color plates for color-efficient and color-deficient subjects delivers test results comparable to pigment color plates under standardized examination conditions. Further studies are needed to examine if the web-based color vision test can also be used as an Internet screening test.
Topics: Adult; Color Perception; Color Perception Tests; Color Vision Defects; Confidence Intervals; Humans; Internet; Luminescent Measurements
PubMed: 15004715
DOI: 10.1007/s00347-003-0915-y -
Eye (London, England) Dec 2015Real-Life Vision Test (RLVT) is a newly developed performance-based measures of functional vision. This present study is designed to determine whether it could be a...
PURPOSE
Real-Life Vision Test (RLVT) is a newly developed performance-based measures of functional vision. This present study is designed to determine whether it could be a meaningful assessment for cataract surgery outcomes evaluation.
PATIENTS AND METHODS
Age-related cataract patients (56) who scheduled for bilateral cataract surgery and 44 age-matched controls were evaluated by four types of measurements: (1) demographic, medical, cognitive and depressive evaluation, and the reaction time testing; (2) clinical measures (visual acuity, contrast sensitivity, stereopsis, and color perception); (3) the 25-item National Eye Institute's Visual Functioning Questionnaire (NEI-VFQ); (4) the RLVT. Spearman's coefficients and multiple regression analysis were conducted to investigate the relationship among RLVT, clinical measures, and self-report assessment of visual function.
RESULTS
The results of RLVT, clinical measures, and NEI-VFQ total scores were improved significantly after cataract surgery. There were no differences between control subjects and post-surgery patients with respect to NEI-VFQ-25 total scores, self-rating depression scale scores and three tasks of RLVT. Change of RLVT was significantly associated with the change of clinical measures in the cataract group. Multiple regression analysis demonstrated that change of distance, intermediate, and near visual acuity, and binocular contrast sensitivity were significant predictors of improvements of RLVT.
CONCLUSIONS
Cataract surgery could improve real-world visual ability effectively for cataract patients. Our study highlights the potential usefulness of RLVT as an adjunct to the current outcomes evaluation system for cataract surgery. The use of RLVT combined with clinical and self-survey methods may be the comprehensive strategy to manifest the impact of cataract surgery on patients' overall vision-related quality of life.
Topics: Aged; Aged, 80 and over; Cataract; Color Perception; Contrast Sensitivity; Depth Perception; Female; Humans; Lens Implantation, Intraocular; Male; Phacoemulsification; Pseudophakia; Quality of Life; Sickness Impact Profile; Surveys and Questionnaires; Vision Tests; Visual Acuity; Visual Perception
PubMed: 26272444
DOI: 10.1038/eye.2015.147 -
BMC Research Notes May 2019Ishihara test is a color vision test, whose results consider that all plates of the test have the same weighting. Rodriguez-Carmona et al. (Aviat Space Environ Med...
OBJECTIVE
Ishihara test is a color vision test, whose results consider that all plates of the test have the same weighting. Rodriguez-Carmona et al. (Aviat Space Environ Med 83:19-29, 2012) proposed an equation to quantify the Ishihara test results (severity index), which took an account the rate of hits from the different plates of the test considering the performance of trichromat or colorblind population. We proposed a correction in Rodiguez-Carmona's equation for the severity index. We evaluated 60 normal trichromats and 107 subjects with congenital color deficiency. We calculated three indexes to quantify the results of each subject: a non-weighted index, a weighted index similar to the Rodriguez-Carmona et al., and a weighted index modified which combined the hit frequency for each plate in a trichromat population and of the error reading frequency for each plate in color-blind populations.
RESULTS
Compared to the non-weighted evaluation, the weighted index was reduced by 22.95%, 32.92%, and 35.38% from trichromats, protan and deutan groups, respectively. Receiver Operating Characteristics (ROC) analysis showed perfect performance of the classifier for all metrics to measure the Ishihara test results. The proposal correction changed significantly the value of the index, but the overall benefits were small.
Topics: Adult; Color Vision; Fluorescence; Humans; ROC Curve; Vision Tests; Young Adult
PubMed: 31138308
DOI: 10.1186/s13104-019-4320-2 -
Optometry and Vision Science : Official... Aug 2012Rarebit vision tests probe for gaps in the neuro-retinal receptive field matrix, using bright micro dots on a dark background. Previous reports have found central-vision...
PURPOSE
Rarebit vision tests probe for gaps in the neuro-retinal receptive field matrix, using bright micro dots on a dark background. Previous reports have found central-vision rarebit tests useful for macular lesions. Their performance with lesions of the anterior visual pathways has not been explored.
METHODS
Twenty-two subjects with optic nerve lesions of light to moderate severities were examined with a novel, self-contained rarebit test. Outcomes were contrasted with results of high-pass resolution perimetry and a threshold letter acuity test.
RESULTS
The results of the three tests differed significantly from those of normal control subjects. There were no meaningful inter-test correlations. Analysis of receiver-operating characteristic curves revealed closely similar powers of discrimination. Mean test time for the rarebit test was 1:42 min, and for the other tests, it was approximately 5 min each.
CONCLUSIONS
The rarebit test appeared highly capable of detecting optic neuropathies and chiasmal lesions. Its simplicity and short test duration indicate a useful role in screening settings.
Topics: Adult; Aged; Humans; Middle Aged; Optic Nerve Diseases; ROC Curve; Reproducibility of Results; Vision Tests; Visual Acuity; Visual Fields; Young Adult
PubMed: 22797513
DOI: 10.1097/OPX.0b013e318264f406