Congenital Color Vision Defects Research Articles

Colour vision screening among Saudi Arabian children

Purpose: To determine the prevalence of congenital red-green colour vision defects among Saudi Arabian male and female children.Methods: The study involved 1638 elementary and high school participants (838 males, and 800 females), who were randomly selected and screened for red-green colour vision defects using the Ishihara (pseudo-isochromatic plates) test. Inclusion criteria were Snellen VA 20/20 or better and absence of known ocular pathologies.Among the females, 0.75% of the 800 participants showed CVD, with 0.25% and 0.5% demonstratingprotan and deutan defects, respectively.Conclusion: The results show that the prevalence of red-green colour deficiency among the female children from central Saudi Arabia is not significantly different from that of female populations inwestern countries. The current prevalence among the males is higher than previously reported for central Saudi Arabia, but less than for Caucasian populations.

異常３色覚と診断された先天赤緑色覚異常者におけるＬａｎｔｈｏｎｙ ｄｅｓａｔｕｒａｔｅｄ ｐａｎｅｌ Ｄ‐１５ ｔｅｓｔの意義

異常３色覚と診断された先天赤緑色覚異常者におけるＬａｎｔｈｏｎｙ ｄｅｓａｔｕｒａｔｅｄ ｐａｎｅｌ Ｄ‐１５ ｔｅｓｔの意義

Introducing a New Computer-based Test for the Clinical Evaluation of Color Discrimination

To evaluate the Portal color sort test (PCST), a new computer-based test of color vision, by comparing it with a series of clinical tests of color vision in normal and color deficient subjects. Prospective clinical laboratory study. Fifty-nine subjects with normal trichromatic vision or with congenital color vision defects underwent a series of color vision tests that included the 15-plate Ishihara test, the D-15 Farnsworth-Munsell test (D-15), the Farnsworth-Munsell 100-Hue test (FM 100-Hue), and the PCST under rigorous standardized conditions, as recommended by the respective manufacturers. The PCST generates a numerical discrimination score comparable to the FM 100-Hue. To test validity, discrimination scores generated by the PCST were compared with scores on the FM 100-Hue. The Spearman rank correlation between discrimination scores on the FM 100-Hue and the PCST was 0.8 (P < .001). Reliability was assessed by asking patients to retake the PCST at a later sitting. Patients retaking the PCST achieved similar scores on their second sitting as on the first. The correlation in the score between the two tests was 0.7 (95% confidence interval [CI]: 0.4-0.9, P < .001). Median (quartiles) time to complete the PCST was 3.1 minutes. This was faster than the FM 100-Hue time (P < .001), but slower than both the Ishihara and the D-15 (both P < .001). This study suggests that the PCST, a test of color vision deficiency, can be used effectively and reliably as a tool for screening (comparable to the Ishihara plates and the D-15) and grading (comparable to the FM 100-Hue) color discrimination ability.

Color vision and contrast sensitivity in epilepsy patients treated with initial tiagabine monotherapy

The purpose of the study was to determine whether the use of a GABAergic antiepileptic drug (AED), tiagabine, affects color vision and contrast sensitivity. Twenty newly diagnosed patients with partial epilepsy (aged 19–72 years), receiving tiagabine as their initial monotherapy for 5–41 months were examined. Color vision was examined with the Standard Pseudoisochromatic Plates 2 (SPP2), with the Farnsworth–Munsell 100 Hue Test (FM100) and with the Color Vision Meter 712 (CVM) anomaloscope. Contrast sensitivity was measured with the Pelli–Robson letter chart. Three patients excluded from the color vision evaluation for congenital red-green color vision defects. Seven out of 17 patients (41%) had acquired color vision deficit examined with the FM100. The CVM anomaloscope revealed minor defects in two patients. Contrast sensitivity function was within normal ranges. The present study suggests that AED therapy with tiagabine, like with other established and newer AEDs may interfere with color perception.

Impact of congenital colour vision defects on occupation

Aims: To investigate whether there is an association between congenital colour vision defects (CVD) and occupational choice and employment history, in order to inform the debate about the value of...

Impact of congenital colour vision deficiency on education and unintentional injuries: findings from the 1958 British birth cohort

Congenital colour vision defects (CVD) are common, inherited (most commonly X linked), non-progressive, and untreatable disorders.1 2 Screening children for these disorders is established practice in the United Kingdom, primarily...

Color vision testing

The science of color vision testing has evolved since its inception in the late 1700s. Since then, the rudimentary technique of comparing color names has been replaced by more sophisticated methods. Commonly used tests in clinical practice today include isochromatic plates, arrangement tests, anomaloscopes, and lantern tests. Each category has unique attributes that make it suitable for a particular clinical situation. The clinician should be aware of the requirements for administering and grading each test type. Factors such as the quality of the illuminant and the size of the field of view are important elements in setting up a proper color vision laboratory. Currently, no treatment exists for congenital color vision defects. However, studies show that diagnosis of these defects early in life may help children adjust better to tasks at school and may help adults understand their limitations at work. Acquired color vision defects are often used as markers of ocular pathology in the clinical setting. Different color vision tests are appropriate for diagnosing the different categories of defects. Sometimes, a battery of tests may be appropriate. This paper is a review of the current knowledge in the field of color vision testing.

The validity of the University of Waterloo Colored Dot Test for Color Vision Testing in adults and preschool children.

Most color vision tests require a high level of cognitive ability and as such are problematic for preschool children and multiply challenged individuals. Our goal was to design a color vision test for these groups and evaluate the clinical utility for preschool children. The University of Waterloo Colored Dot Test (UWCDot) for Color Vision Testing requires the subject to distinguish a colored disc from seven gray discs. The target disc was a Munsell color along the deutan, protan, or tritan confusion line with gray. The first phase estimated the sensitivity and specificity of the test for adults. Thirty-one adults with normal color vision and 21 adults with congenital red-green defects participated. In the second phase, the utility of the UWCDot test for screening preschool children was determined. Subjects were 281 males and 269 females aged 2.5 to 5 years with normal vision. Their color vision was also assessed with the Standard Pseudoisochromatic Plates, Part 1 (SPP1). The sensitivity and specificity of UWCDot for adults approached the values for the desaturated D-15 when subjective responses were scored. Monitoring fixational eye movements produced sensitivity and specificity values that were similar to the anomaloscope. After adjusting the scoring criterion for the preschool children by using the females as a control, 2.9% of the males were identified as red-green deficient, 1.8% were blue-yellow deficient, and 3.2% had an unclassified deficiency. By definition, 1% of the females failed the test. Counting fixational eye movements was not a useful scoring method in the preschool children. Comparisons with SPP1 indicated that the UWCDot uncovers approximately 35% of the individuals with definite red-green color vision defects. Our results indicate that the UWCDot is capable of detecting approximately 35% of the preschool children who have a congenital red-green color vision defect. These individuals are likely to have a more severe deficiency.

Pigment gene expression in protan color vision defects

We screened 150 male eye donors and identified four who did not have or express L pigment genes, consistent with each of them having a congenital protan color vision defect. One donor was identified as a protanope because he had and expressed a single X-chromosome photopigment gene that encoded an M pigment. Three were categorized as protanomalous because each expressed significant levels of genes specifying two spectrally different M pigments. The first gene in each of the protanomalous arrays was expressed the most and encoded an M pigment that differed in amino acid sequence from M pigments in color normal men.

Molecular genetic detection of female carriers of protan defects

Females heterozygous for congenital colour vision defects are of interest because they are believed to have cone photoreceptor ratios and cone photopigments that differ from normal. We describe a molecular genetic method to identify protan carriers that involves characterizing the genes that occur in the most upstream position in each of the X-chromosome photopigment gene arrays.

A new colour vision test for clinical use

Several tests are available for assessing colour vision but they can be expensive, complicated or too time consuming to perform. We have produced a new plate test based on pseudoisochromatic principles. The test, using an error score, examines both the red-green and blue-yellow axes, with four levels of difficulty for each axis. Results from a pilot study show that error scores from congenital red-green blind subjects are significantly higher than those of age-matched controls (p < 0.01) only when using the red-green plates and not the blue-yellow plates. In optic neuritis patients, error scores using both the red-green and blue-yellow plates were significantly higher than those of controls throughout the 6 month follow-up. The test, including scoring, takes 6 minutes to complete. These preliminary results suggest that the new test is effective for screening congenital red-green blindness and monitoring colour vision defects in acquired diseases such as optic neuritis.

Prevalence of congenital red-green color vision defects in Arab boys from Riyadh, Saudi Arabia.

The prevalence of congenital red-green color vision defects (CVDS) is both racial and gender dependent. Red-green color vision defects (CVDS) have been screened for among Arab boys from Riyadh, Saudi Arabia, by using both the Ishihara plates and the D 15 test. The results indicate a prevalence of 2.93%. Deutan defect was present in 1.95% of the subjects, protan defect in 0.49% and unclassified color defect in 0.49%. This result confirms the previously reported low prevalence of congenital red-green CVDS among adult Arab males from the central region of Saudi Arabia.

Screening for congenital colour vision defects

AbstractA prospective comparison between the Ohkuma1 and Ishihara2 pseudoisochromatic (PIC) plates was carried out in a group of 400 patients attending a general ophthalmology practice. The sensitivity of the Ohkuma test was compared to the Ishihara test, and the specificity of both was determined by reference to anomaloscopy as a gold standard.Both tests correctly identified the same group of 24 patients as having a red/green confusion axis, and the Ohkuma test was equally as sensitive as the Ishihara. The grading plates in both tests are unreliable, but the Ohkuma test is quicker, easier to administer, gives less ambiguous responses and has a clearer cut‐off score for abnormality. On the basis of this experience the Ohkuma test is recommended as more appropriate for routine colour vision screening than either the 24 or 38 plate Ishihara tests.

Quantitative Scoring Methods for D15 Panel Tests in the Diagnosis of Congenital Color Vision Deficiencies

Farnsworth's standard D15 and L'Anthony's desaturated D15 panel tests were administered to 99 congenital red-green color defective subjects. The results were analyzed in three ways: (1) by summing the color differences between adjacent caps according to Bowman, (2) by averaging color difference vectors (CDV) according to Vingrys and King-Smith, and (3) by visually inspecting and counting the crossings. The Bowman measure was highly correlated with one of the CDV measures but provides less information regarding a cap arrangement. The desaturated D15 test can be expected to misclassify 5% of dichromats by type (protan/deutan) compared to a type misclassification rate of less than 0.1% for the D15 panel test. The correct diagnostic rates for type were 45% for the standard D15 test and 58% for the desaturated D15 test. However, the improvement in correct diagnostic rate for the latter test was accompanied by an increase in the misdiagnostic rate from 2 to 10%. The main value of the desaturated D15 test in congenital color vision diagnosis would seem to be in providing classification of those subjects who pass the standard D15 test. Quantitative scoring of the tests provides a good estimate of severity of defect. Visual inspection provides a similar diagnostic rate to CDV analysis, but has a lower type misdiagnostic rate at the desaturated D15 test and is more likely to be correct when the two methods disagree. We suggest that quantitative scoring techniques are of limited benefit for the clinical diagnosis of congenital color vision defects but that they are of use in clinical trials or for the monitoring of changes in color vision over time.(ABSTRACT TRUNCATED AT 250 WORDS)

Use of the Farnsworth-Munsell 100-Hue test in the examination of congenital colour vision defects.

Results for the Farnsworth-Munsell 100-Hue test are reported for 238 male subjects with congenital colour vision defects (47 protanopes, 17 protanomalous trichromats, 57 deuteranopes and 117 deuteranomalous trichromats). The results are analysed in terms of the error score and the presence of an axis of confusion. A wide range of results is obtained in each diagnostic group and the error score cannot be used to distinguish between dichromats and anomalous trichromats. Approximately 50% of subjects with anomalous trichromatism obtain error scores less than 100 without an axis of confusion. These subjects could be mistakenly identified as having normal colour vision if pseudoisochromatic and colour matching tests are not employed. The prime use of the F-M 100 Hue test is in vocational guidance.

Color vision in diabetic school children.

The color vision of 64 diabetic school children was studied. Acquired color vision defects due to diabetes could not be found in any of the children. Two of the children had a congenital red-green color vision defect. In the examination, three different pseudoisochromatic plate tests (Isihara, Standard Pseudoisochromatic Plates part 2, and Lanthony Tritan Album) were used as well as the Nagel anomaloscope and three different cap arrangement tests (Panel D 15, Lanthony Desaturated Panel, and Farnsworth-Munsell 100 hue). The plate tests and the anomaloscope examination were fast, reliable, and well accepted by the children. The cap arrangement tests took more time, and many of the children neither liked nor properly performed these tests. Twelve color dependent glucose strip tests for diabetes care at home were also studied. A few of the youngest school children made mistakes in interpreting the colors of these strips, although their color vision was normal.

An averaging method for the interpretation of the Farnsworth-Munsell 100-Hue test — I. Congenital colour vision defects

An averaging method for the interpretation of the Farnsworth-Munsell 100-Hue test — I. Congenital colour vision defects

Eye disease and color defects

The groundwork for understanding color defects in eye disease was established by the end of the nineteenth century. Thereafter the field was neglected as scientists concentrated on studies of normal color vision and congenital color vision defects. Spurred by the development of the Farnsworth 100 hue-test, interest was renewed in the 1950s. The past 25 years have seen an explosion of interest in color defects in eye disease. The International Research Group on Color Vision Deficiencies has played an important role in this activity. The development of new clinical tests and instruments as well as refinement of laboratory techniques are among the important developments.

New investigations concerning the relationships between congenital colour vision defects and road traffic security

New extentive experiments demonstrated that: (a) protan observers are more deficient than deutan ones with regard to perception distances of some traffic panels, of vehicle red stop lights, of vehicle red rear-position lights and of white, yellow and red reflectors. Contrarily, deutan observers are more deficient than protan ones for the distinction of differently coloured traffic lights and vehicle rear lights; (b) protan and deutan drivers are nevertheless not responsible for more traffic accidents than drivers with normal colour vision; (c) this apparent contradiction is due to psychological compensation mechanisms. The practical conclusions are: (a) that persons with defective colour vision need not to be excluded from non professional road traffic; (b) that it is nevertheless useful that they should be aware of their handicap; (c) that the red traffic signal has to be larger than the other ones; and (d) that the stop and red position lights of vehicles must be sufficiently intense and that the filters transmitting only pure red should be avoided in them.

The Farnsworth Dichotomous Test ‐ The Panel D‐15

The Panel D-15, the conditions for Its use and the rationale for Its performance are reviewed and new informatlon in the form of colour difference data Is presented. Prediction of colour defective performance using standard response functions is explained. Studies on the qualitative and quantitative value of the test for diagnosis of congenital colour vision defects are reported whlle the unlque aspects of the test for examination of acquired defects are discussed.