Color discrimination assessment in patients with hypothyroidism using the Farnsworth–Munsell 100 hue test

Abstract

There is evidence in the literature that hypofunction of the thyroid gland (hypothyroidism) affects color vision in rodents by influencing the production of visual pigment opsin. The effect of hypothyroidism on color vision in humans has not been examined in any great detail. In this cross-sectional study we evaluated color discrimination using the Farnsworth-Munsell 100 hue test (FM-100) in 25 individuals with pre-treatment hypothyroidism (mean age 38±9.2 Yrs), and a control euthyroid group, n=26 (mean age 39.6±8.4 Yrs). There were no statistically significant difference in the total error score (TES) between the groups, but the hypothyroid group had a significantly greater partial error scores (PES) along the blue-yellow (B-Y) axis compared to the red-green (R-G) axis. No statistically significant differences in B-Y and R-G PES were observed in the control group. This study shows that hypothyroidism affects color vision in humans, with impairment being more pronounced in the blue-yellow color subsystem.

Colour discrimination in post-COVID-19 observers assessed by the Farnsworth-Munsell 100-Hue test

“…(We are grateful to the authors for providing their data.) For seven hue bands, we found no statistically significant differences (p>0.119); for three hue bands, R-YR, GY-G and P-PR, √PES for pCPs were significantly lower (p£0.04), which could be accounted for by a lower illumination (285-295 lux) in 41 .…”

“…Refs. 37,41,42,45 ), from pCPs' possible impairment of colour discrimination, we compared √PES medians for each hue band with those obtained for the control group 41 . (We are grateful to the authors for providing their data.)…”

“…In order to evaluate whether more common are errors along the cardinal axes of perceptual colour space, we partitioned the TES into scores along the B-Y and R-G axes 31,41,42,66 . B-Y PES (caps 1-12, 34-54 and 76-85) and R-G PES (caps 13-33 and 55-75) were calculated and analysed according to Smith et al 31 For further analysis, the corresponding √B-Y PES and √R-G PES were used.…”

“…Res. 12,[34][35][36] ), pre-and post-surgery cataract 37 , and systemic diseases, such as diabetic retinopathy [38][39][40] or hypothyroidism 41,42 .…”

Could exists a potential relation between COVID-19, prolonged digital screen exposure, and acquired color vision deficiencies? A concise answer

“…• Alterations in color vision can occur as a result of various diseases such as hypothyroidism [29], pituitary adenoma [30], Parkinson's disease [31,32], diabetic retinopathies [33], prosopagnosia [34], and others. The association between these diseases and color vision has been extensively investigated utilizing the Farnsworth-Munsell 100-Hue Test in most research published studies.…”