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Background: The Farnsworth-Munsell 100-hue test (FM100-hue) is a color-arrangement test wherein a patient must arrange 85 caps into color order. It is a well-known and widely accepted test, but it is not often used in primary eye care practice because it takes a fairly long time (about 10 minutes) to administer. However, this case report will show the usefulness of the test where other tests of color vision were not able to give a clear picture of a patient's color vision issue. Case Report: A 17-year-old Caucasian female presented with a complaint of having trouble distinguishing different shades of similar colors. The patient had a comprehensive eye exam a week prior to this visit, which did not reveal any significant findings. No family history of color vision deficiency was reported. She passed all color vision screening book tests. Additional tests, including the Farnsworth D15, were passed, but with some anomalies. The FM100-hue test was definitively failed and showed a severe (total error score = 372), non-specific color vision issue with errors in every part of the color circle. The patient was diagnosed as likely having genetically normal color vision, but with very poor hue discrimination. Conclusion: The case shows that the FM100-hue test can identify non-specific color vision issues, even when other color vision tests cannot, and the test has utility in clinical practice. [ABSTRACT FROM AUTHOR]

Background: Reverse high-contrast (white-onblack) visual acuity has been shown to improve visual acuity in older patients and patients with pathology under photopic testing. In this study, we investigated whether reverse contrast results in improved visual acuity at mesopic light levels. Methods: Monocular visual acuities (logMAR) were assessed at four different light levels (1 photopic {94 cd/m2} and 3 mesopic {3 cd/m2, 0.75 cd/m2, and 0.38 cd/m2}) in 47 visually normal subjects (27.4±9.3 years). Visual acuity was assessed using an E-ETDRS algorithm, in standard and reverse contrast, at 3 m. Repeated measures ANOVA with post-hoc Tukey testing was used to analyze the data across the light levels. Results: The mean standard contrast visual acuity was -0.07±0.06 under the photopic condition, 0.06±0.08 at 3 cd/m2, 0.17±0.08 at 0.75 cd/m2, and 0.28±0.09 at 0.38 cd/m2. For reverse contrast, it was -0.08±0.06 under the photopic condition, 0.01±0.07 at 3 cd/m2, 0.12±0.08 at 0.75 cd/m2, and 0.22±0.09 at 0.38 cd/m2. There was a significant improvement in visual acuity using reverse contrast under all mesopic light levels (p<0.001), but not under photopic conditions (p=0.15). Conclusions: At mesopic light levels, there were significant differences between standard and reverse contrast. The use of mesopic reverse-contrast visual acuity could be another way to detect subtle changes in visual acuity. Reversecontrast presentations under low lighting conditions may be advantageous for a patient's visual acuity. [ABSTRACT FROM AUTHOR]

Background: The Lanthony desaturated color vision test is a color arrangement test wherein a patient must arrange 15 caps into color order. It is a difficult test for color-normal patients and is even more challenging for color vision-deficient patients due to its low saturation, which makes the cap-color differences fairly small. Despite the challenge, this case report will show that the test may not always be reliable. Case Report: A 25-year-old Caucasian male returned to our office for continued evaluation for color vision deficiency. He had previously been diagnosed with protanopia based on anomaloscope testing, which was consistent with other color tests. The patient had previously shown learning on the easier Farnsworth saturated color test and was interested in attempting to learn a harder test. The patient was sent home with a Lanthony color test and Richmond Illuminator. He returned for follow-up testing, which showed that he was able to score perfectly on the Lanthony desaturated color test, which was very surprising. Conclusion: This case shows that for some highly motivated patients, the Lanthony D15 color test may be subverted, and knowledge of this possibility is important for clinicians to consider. [ABSTRACT FROM AUTHOR]

Background: Several validated, age-specific recognition visual acuity measurement charts used in research and vision screenings follow national and international guidelines for standardized eye charts. The Kindergarten (aka Sailboat) chart is widely used to measure visual acuity in children, but no literature has evaluated its accuracy. This study evaluates the chart against a validated chart. Methods: School children (n = 51, 42% female, 58% male) were recruited from El Monte, California. The mean age of the participants was 5.7 years (SD = 1.7 years). Visual acuities were assessed with Lea symbols, a validated chart, and the Kindergarten chart on one randomized eye per child. Acuities (converted to logMAR) were recorded using the letter-by-letter method. Data were analyzed using letter-by-letter and line-by-line scoring (≥50% on a line) using 2-tailed paired t-tests and Bland-Altman analysis, including 95% limits of agreement (LOA). Results: Mean (±SD) logMAR acuities for the Lea symbols chart were 0.15 ± 0.16 and 0.14 ± 0.17 for letter-by-letter and line-by-line methods, respectively. For the Kindergarten chart, it was 0.25 ± 0.20 for both methods. The approximate 1-line difference between the charts using either scoring method was significantly different (p < 0.001). The 95% LOAs were ±0.28 for both scoring methods. Conclusions: The Kindergarten chart resulted in a visual acuity approximately one line worse than the chart using Lea symbols. The Kindergarten chart had poor agreement with the chart using Lea symbols. Clinicians using the Kindergarten chart should be cautious in interpreting the recorded visual acuity, as this could lead to false positives and subsequent over-referral of children. It would be more prudent simply to discontinue using the Kindergarten chart, especially when much better visual acuity charts for children are readily available. [ABSTRACT FROM AUTHOR]