Acuity Color Research Articles

Age-related changes of color visual acuity in normal eyes.

PurposeTo evaluate the age-related change in color visual acuity (CVA) in normal eyes.MethodsIn total, 162 normal eyes (162 subjects, women: 52, men: 110, age range: 15–68 years) with best-corrected visual acuity (BCVA) ≥20/13 were enrolled. Fifteen colors from the New Color Test (chroma 6) were applied to Landolt “C” rings, white point D65 was applied as background, and a luminance of 30 cd/m2 was set for both the rings and the background. These rings were used to measure the chromatic spatial discrimination acuity as the CVA value, while changing the stimulus size. Correlations of the CVA value of each color and age were evaluated. Mean CVA values of all 15 colors (logarithm of the minimum angle of resolution) were compared between age groups in 10-year increments.ResultsNine CVA values (red, yellow-red, red-yellow, green, blue-green, green-blue, purple, red-purple, and purple-red) were negatively correlated with age (all p<0.05); the remaining six (yellow, green-yellow, yellow-green, blue, purple-blue, and blue-purple), as well as BCVA were not. The age groups with the best to worst mean CVA values of 15 colors were as follows: 20–29 (mean ± standard deviation, 0.303 ± 0.113), 30–39 (0.324 ± 0.096), 10–19 (0.333 ± 0.022), 50–59 (0.335 ± 0.078), 40–49 (0.339 ± 0.096), and 60–69 (0.379 ± 0.125) years. There were statistically significant differences between mean CVA values of the following groups: 20–29 and 40–49 years; 20–29 and 60–69 years; 30–39 and 60–69 years (all p<0.01).ConclusionsThe CVA values related to the medium/long-wavelength-sensitive cones were more susceptible to aging than those related to the short-wavelength-sensitive cones. This differed from previous reports, and may be related to the difference in the range of foveal cone function evaluated with each examination.

Is there an association between Perceptual Ability Test scores and color vision acuity?

The purpose of this study was to determine if there is an association between Perceptual Ability Test (PAT) results and color vision deficiency (CVD). Three consecutive classes of first-year dental students (n=291) voluntarily participated in the study. The Farnsworth-Munsell 100 Hue Color Vision test (FM-100) was administered to students beneath a Macbeth Judge II viewing booth that provided ideal lighting conditions to ascertain CVD. Results of FM-100 test were recorded as total error scores (TES). Color acuity was scored as superior (TES 0-16), average (TES 20-100), or poor (TES>100). Additional information of age, sex, ethnicity, and time to complete the FM-100 was obtained. Multiple linear regression was used to determine the association between PAT and CVD while adjusting for age, sex, ethnicity, and time to complete the FM-100 test. TES ranged from 0-244. There were 132 students with superior color acuity, 161 with average, and eight with poor acuity. Females performed better than males on the FM-100 test. Time to complete the FM-100 test ranged from 3:40 minutes to 25:12 minutes. There was a strong relationship between PAT scores and CVD (P=0.0003). A 1-unit increase in PAT scores was found to result in a 9% decrease in TES; indicating that students with higher PAT scores are less likely to have CVD. The PAT may be a preliminary screening instrument to identify students who may have CVD. The FM-100 test can then confirm the presence of CVD. Students with CVD may desire to improve dental shade matching skills through targeted training and education.

Contrast Acuity With Different Colors in Parkinson's Disease

Abnormal color vision and contrast acuity may have significant impact on daily activities. Evaluate color visual acuity, at high and low contrast, in Parkinson's disease (PD) and controls using an iPad application. Color visual acuity was tested with the Variable Contrast Acuity Chart (King-Devick Test LLC, Oakbrook Terrace, IL) on an iPad 2 at 40 cms using five colors (red, green, blue, yellow, and black) at low (2.5%) and high (100%) contrast. A numerical score (0-95) was assigned based on the number of correctly identified letters. Thirty-six PD (mean ± standard deviation age 68 ± 10 years) and 36 controls (72 ± 11.2 years) were studied. PD disease duration was 6.4 ± 4.6 years; MDS-UPDRS part II was 11.7 ± 7.0, and part III was 24.5 ± 9.9. After adjusting for age and sex, PD patients had significantly (P < 0.05) lower scores at high (100%) as well as low (2.5%) contrast for all five colors tested (red, green, blue, yellow, and black), except yellow low contrast (2.5%; P = 0.10). The largest effect size (0.88) was with yellow high contrast, and the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy using a cut-off score of 82 was 31%, 97%, 92%, 58%, and 64%, respectively. No correlation to disease duration was found. This iPad application may be a simple-to-use biomarker for assessing color vision in PD. Further research is needed to determine disease specificity and whether there is a role in monitoring disease progression, treatment response, and identifying prodromal PD.

Dental Shade Matching and Value Discernment Abilities of First-Year Dental Students.

To determine if Farnsworth-Munsell 100 Hue Test, Perceptual Ability Test, gender, age, ethnicity, and time predict dental shade matching and value discernment in first-year dental students. Farnsworth-Munsell 100 Hue Test was administered to 95 first-year-dental students beneath a Judge II booth (color temperature of 6500°K, and color rendering index of 90). Students also arranged 16 masked shade tabs from a Vita Classic shade guide by value (lightest to darkest) and matched together 16 pairs of masked shade tabs from two Vita Classic shade guides. Ethnicity, age, Perceptual Ability Test scores, gender, and time to complete the tests were recorded. Associations and correlations were investigated using chi-square, Tukey-Kramer HSD, standard least square, and multilinear regression (p < 0.05). Total error scores on the Farnsworth-Munsell 100 Hue Test ranged from 0 to 144. Forty-eight students exhibited superior color acuity, 45 average, and two poor. The mean number of correct answers for matching shade tabs together was 11.6, and 6.1 for arranging the shade tabs by value. Females performed statistically better than males on the Farnsworth-Munsell 100 Hue Test and shade tab matching. Better color discrimination identified by lower total error scores on the Farnsworth-Munsell 100 Hue Test was directly correlated to greater ability to match shade tabs together. Perceptual Ability Test scores had slight significance. As the scores increased there was slightly better performance on the Farnsworth-Munsell 100 Hue Test. Older participants performed better than younger subjects on the value test. No other correlations were significant for any of the tests. Females and individuals who performed better on the Farnsworth-Munsell 100 Hue Test have improved dental shade-matching ability.

Effect of Background Luminance Level on the Assessment of Color Visual Acuity Using Colored Landolt Rings in Young Healthy Subjects

ABSTRACTPurpose: To evaluate the color visual acuity (CVA) of young healthy subjects using colored Landolt rings and the effect of background luminance level on the CVA.Materials and methods: We measured the CVA of 20 young healthy subjects (age: 23.8 ± 3.8 years) with different colors using a computer and a liquid crystal display, with 15 Landolt ring colors (30 cd/m2) with a background luminance of 30 cd/m2, and then 100 cd/m2. We then used different background luminance levels (15–50 cd/m2) using four Landolt ring colors (red, green–yellow, green, and blue–green) to evaluate the effect of the background luminance level on CVA.Results: The CVA significantly differed among the colors with a background luminance of 30 cd/m2 (p < 0.0001). Green–yellow and blue–purple had poor CVA (high LogMAR value; 0.808 ± 0.107 and 0.633 ± 0.150, respectively) with a background luminance of 30 cd/m2 (same luminance as the Landolt rings). There were no significant differences in the CVAs among the colors with a background luminance of 100 cd/m2 (p = 0.5999). There were no significant difference in the CVA between background luminance 30 cd/m2 and other luminance level ranging from 28 to 32 cd/m2 for colors of red, green–yellow, green, and blue–green.Conclusions: The results reveal that the background luminance of Landolt rings affects the CVA. Distinctive CVAs for each color are measured by equalizing the luminance between the Landolt ring and the background. We consider that the poor CVAs of these colors reflect the visual function of S-cone, because GY and BP are included in the confusion locus of tritan axis on the chromaticity diagram. We believe that CVA assessment may be useful for individuals who have known or suspected ocular dysfunction or color vision deficiencies.

A Review of Color Science in Dentistry: The Process of Color Vision

This article is one of a series review articles discussing the applications of color science to the clinical practice of dentistry. In this segment, the basic perception of color by humans, as well as, tests for color visual acuity is discussed.

Dynamics of retinal injury after acute optic neuritis.

We set out to assess the dynamics of retinal injury after acute optic neuritis (ON) and their association with clinical visual outcomes. Thirty-one consecutive patients with acute ON were prospectively analyzed over a 6-month follow-up period. Each month, we used optical coherence tomography (OCT) to assess the thickness of peripapillary retinal nerve fiber layer (pRNFL) and segmented macular layers, as well as high-contrast visual acuity, low-contrast visual acuity (LCVA), color visual acuity (CVA), and visual fields (VF). In this prospective study, we found that 6 months after clinical onset, ON eyes suffered a reduction in pRNFL (-45.3 μm) and macular thickness (-17.3 μm). Macular atrophy was due to the decrease of macular RNFL thickness (-7.8 μm) and that of the ganglion cell layer and inner plexiform layer (GCIP, -11.3 μm), whereas the thickness of the outer retinal layers increased slightly. The macular RNFL and GCIP thickness decreased in parallel, yet it always occurred more rapidly and more severely for the GCIP. The change in the GCIP thickness in the first month predicted the visual impairment by month 6; a decrease ≥ of 4.5 μm predicted poor LCVA (sensitivity of 93% and specificity of 88%), and a decrease of ≥ 7 μm predicted poor VF and CVA (sensitivity of 78% and 100% and specificity of 63% and 66%, respectively). Retinal axonal and neuronal damage develops quickly after ON onset. Assessment of ganglion cell layer thickness by OCT after ON onset can be used as an imaging marker of persistent visual disability.

Cultural Color Inspiration: Learning Color Context in Cultural Reflections

The purpose of this study is to explore creative color teaching activities and their value in education. To understand the teaching method used in color science in university foundation design courses and to lead students to comprehend their own culture in application of design, the study explores solutions and strategies from the perspective of the curriculum. The study is based on the concept of action research used in a course the researcher conducted for half a semester. This study proposes to develop the color sensitivity of students, and to inspire their cultural consciousness for creative color ombination. The conclusion has three principal aspects. First, for curriculum design, the course should integrate issues to explore culture. Students could search for the mark of culture in daily life and flexibly apply their five senses to enhance their observation in color exploration and materials application. Second, for teacher tutorial, teachers should encourage hinking in every step and provide comments or direction. Teachers could implement teamwork activities to motivate the students to be inspired in their creativity. Third, for student learning, in observing culture, self-examination and group participation are essential tools in discussion. Feedback can motivate students to learn, encourage diversity in their abilities, and reach a wider field. The research suggests that chromatics foundation curriculum design should emphasize the importance of course structure and the combination of activities. Connecting the local color survey properly could raise the capability in analyzing a larger project. Moreover, self-examination transforms into the sensibility of cultural aesthetics, and develops the sense of good taste. It arouses the strength of color application, broadens range of knowledge and depth in professional development. Eventually, the learner can develop practical design talents in color acuity and observation.

Conventional and digitally assisted shade matching – A comparative study

AimThe purpose of this study was to compare conventional shade matching method with digitally assisted shade matching method and to evaluate observer's shade matching ability using conventional method in day light as well as studio environment and to compare it with digital. Materials and methodsThe ten observers with normal vision and color acuity participated in the study. Twenty subjects selected, satisfying exclusion and inclusion criteria of the study. Target tooth selected for study was vital right maxillary central incisor. A Vita classical shade guide was used for shade matching. Computer system, digital camera and Digital color matching software and were used for digitally assisted shade matching method. For conventional shade matching, observers performed shade selection in day light as well as in studio environment, at the same time digital images of the target tooth were made, and processed through the digital color matching software for digitally assisted. ResultsThe chi-square analysis showed that the observer's matching ability is not significantly different in either day light (P = 0.164) or in studio environment (P = 0.300). Overall correct matching ability of ten observers was 58.5% and 52.5% in day light and in studio environment respectively. ConclusionsWithin the limitations of current study a new computer matching method was proposed and found to be superior to the conventional shade matching method. Large variation in observer's ability in conventional shade matching was also found.

Development of a New Testing System of Color Visual Acuity and an Example of Examination Outcome

Development of a New Testing System of Color Visual Acuity and an Example of Examination Outcome

A Study of Color Planning Criteria Used by Noted Designers

This study was conducted to identify color planning criteria that noted designers reported using in textile, sig–nage, interior, and architecture projects. The national sample consisted of designers (n = 41) who were nominated as either accomplished colorists (n = 23) or comparably accomplished generalists (n = 18). Data were collected through an in–person interview regarding a self–selected project and a standardized color acuity test. Potential sources of variation in color acuity between the colorists and generalists were examined. No statistically significant differences were found between groups, but the total sample scored significantly better on hue discrimination when compared to the normative adult mean. Primary findings showed that noted designers employed five categories of criteria in the design process: compositional to create unity or emphasis, or to manipulate space and form with color; symbolic to express design concepts with color; behavioral to address activity needs with color; preferential to consider individual color preferences or market trends; and pragmatic to support maintenance needs and preconditions with color. Over half of the sample (52 percent) used two or more color categories per project, and exploratory analyses revealed that colorists used compositional color criteria more frequently than generalists. The results provided a basis for formulating a framework of color planning.

Ocular Manifestations of Diseases of the Paranasal Sinuses

When making a survey of the eyes of patients who suffer from paranasal sinus diseases the ophthalmologist should study— 1. Color perception, central and peripheral; 2. Color acuity, central; 3. Visual acuity, central; 4. Campimetric measurements of the blind spot; 5. Peripheral field studies of form and colors; 6. Refractive errors; 7. Derangements of binocular vision; 8. Scotoma with the tangent screen; 9. Radiographs. Frontal Sinus Among the diseases of the frontal sinus presenting ocular manifestations are mucocele a distention by mucus, and empyema, of pus. At the upper and inner angle of the orbit a tumor can be palpated, accompanied by sensitiveness upon pressure over the frontal bones (Ewing's sign), tenderness at the attachment of the pulley of the superior oblique muscle, with headache and supraorbital pain. There are diplopia and epiphora, with an enlargement of the blind spot of Mariotte. Osteoma also causes a bulging of the upper and inner angle of the orbit, which is dense, painless, and of slow growth, being readily differentiated from mucocele and empyema by radiological studies. Ethmoids Knapp's retention cyst and mucocele of the ethmoid are synonymous. The lesion appears in the upper and inner angle of the orbit, above and behind the internal canthal ligament, displacing the eyeball downward and outward, and is differentiated from exostosis by an exploratory incision and the X-ray, preferably the latter. In ethmoiditis, one may find tumefaction of the inner third of the lid, diplopia, epiphora, faulty movements of the eyeball, and severe pain (ethmoidal syndrome). In posterior ethmoiditis of the sclerotic type, the pain is perhaps more severe (Meckel's ganglia syndrome), the threshold for color acuity is diminished, the blind spot of Mariette presents a concentric enlargement, the peripheral visual fields are contracted for form and color, central vision is diminished, and there is a central scotoma, differentiating the disease from sphenoiditis. The otolaryngologist generally makes the diagnosis, the radiologist concurring. Antrum When the antrum is the seat of the disease manifold symptoms are presented—edema of the lids, chemosis of the conjunctiva, edema of the optic nerve, distended blood vessels (veins), and affections of the lacrimal apparatus. The disease is generally diagnosed by the otolaryngologist and the radiologist. Foreign bodies in the paranasal sinuses may have entered through the orbit, or directly through the anterior wall; for instance, shot, shrapnel, missiles from small arms or machine guns, flying particles due to industrial traumatism or explosions, and possible accidental trauma during surgical operations. The diagnosis is essentially dependent upon the X-ray. Orbital abscess develops from pus escaping through the os planum into the orbital cavity.

THE EYES AND EARS OF EMPLOYEES OF TRANSPORTATION COMPANIES.

Color-blindness is an abnormal condition of the visual apparatus, causing an inability to accurately, invariably and properly distinguish the colors of the solar spectrum. Several varieties exist, but the most frequent is that causing difficulty or impossibility in distinguishing between red and green, which is especially unfortunate, as these colors are universally adopted as important signals in transportation service. Investigations indicate the universality of chromatic aberration in all observed nations, but with diminished frequency in the educated, and in peoples possessing great love for colors and artistic decorations such as the Africans, Japanese and Chinese. Indeed, it is claimed by some observers that the people of India are able to perceive 300 different shades of colors not perceptible to European eyes. No evident physical manifestation exists rendering an objective diagnosis possible. Opinions as to color visual acuity must therefore rest on tests, which are well described in text-books. My brother,