The Color Vision Disorder in Diabetic Patients

Introduction: The visible spectrum (about 400 to 700 nm) with a mosaic of three classes of photoreceptors compose the human visual system. They are sensitive to different wavelength ranges with overlapping. The receivers have high sensitivities at short wavelengths (~440 nm), medium (~535 nm), or longer (~565 nm), which are S, M, and L cones, respectively. The study aimed to determine blue color vision defects in diabetes mellitus. 
Methods: A cross-sectional study was done at an ophthalmology clinic on 200 eyes (right and left) of patients with DM for a period of 5 one years (2021). Ishihara plates were used initially for screening. The D-15 test was performed for the evaluation of color vision. 
Results: The mean age of the sample was 45.66±15.65 years. The most frequent disorder visualized was tritanomaly in 63%, followed by trichromate in 27%, and the least disorder was deuteranomaly in 2%. In addition, mixed disorder is seen in 8% of cases. In relation to laterality, right eye tritanomaly was found in 34%, while the left eye was recorded in 29%. The right eye trichromate was observed in 12%, whereas the left eye was reported in 15%. The left eye deuteranomaly was reported more than the right (1.5% vs. 0.5%). 
Conclusion: Color vision evaluation with good screening color vision test can be detected even before clinically visible diabetic retinopathy. Early detection was helpful in the prevention of vascular changes in the retina. All diabetic patients should be given proper awareness and health education regarding color vision deficiency. Timely assessment of color vision may detect tritanomaly earlier in diabetics.


Introduction
Definitely, the spectral sensitivities are evaluated by the specific photopigment molecules. 1 The single receiver type cannot show the difference between wavelength changes and intensities changes. The probability that a given photon is absorbed by a photopigment depends on the wavelength. All subsequent events in the receiver are wavelength independent. Thus, the wavelength data can be extracted by comparing the responses among different receiver classes. 2 Macular degeneration cause damage to the retina, which is a complication of diabetic retinopathy and causes tritanopia. 3 The diffuse color vision impairment in DM along both the blue/yellow and red/ green axis is affected, and this is strongly associated with the degrees of diabetic retinopathy or macular edema. 4 Diabetic retinopathy (DR) is a primary cause of visual impairment worldwide. 5

Introduction:
The visible spectrum (about 400 to 700 nm) with a mosaic of three classes of photoreceptors compose the human visual system. They are sensitive to different wavelength ranges with overlapping. The receivers have high sensitivities at short wavelengths (~440 nm), medium (~535 nm), or longer (~565 nm), which are S, M, and L cones, respectively. The study aimed to determine blue color vision defects in diabetes mellitus. Methods: A cross-sectional study was done at an ophthalmology clinic on 200 eyes (right and left) of patients with DM for a period of 5 one years (2021). Ishihara plates were used initially for screening. The D-15 test was performed for the evaluation of color vision. Results: The mean age of the sample was 45.66±15.65 years. The most frequent disorder visualized was tritanomaly in 63%, followed by trichromate in 27%, and the least disorder was deuteranomaly in 2%. In addition, mixed disorder is seen in 8% of cases. In relation to laterality, right eye tritanomaly was found in 34%, while the left eye was recorded in 29%. The right eye trichromate was observed in 12%, whereas the left eye was reported in 15%. The left eye deuteranomaly was reported more than the right (1.5% vs. 0.5%). Conclusion: Color vision evaluation with good screening color vision test can be detected even before clinically visible diabetic retinopathy. Early detection was helpful in the prevention of vascular changes in the retina. All diabetic patients should be given proper awareness and health education regarding color vision deficiency. Timely assessment of color vision may detect tritanomaly earlier in diabetics.

Sriwijaya Journal of Ophthalmology
Journal Homepage: https://sriwijayaopthalmology.com/index.php/sjo colors (loss of discrimination along the blue/yellow axis). Tritan defect is explained by a higher susceptibility of short wavelength cones in the retina and early yellowing of the lens in the diabetic eye.
Other studies reported discrimination along the blue/yellow and red/green axes.  Ishihara plates were used initially to screen out any congenital defect. D-15 test was performed for evaluation of color vision. The test was performed thrice, and an average result was considered. Data were entered using the latest version 20 of SPSS, and chi-square was used to assess the association. P value <0.05 was considered statistically significant.

Results
The mean age of the sample was 45.66±15.65 years. 22% of patients belonged to the group (30-40 years), 45% belonged to the group (41-50 years), and above 50 years documented 33% of cases. Males were 57%, and females were 43%. 44% lived in urban areas, and 56% of cases lived in rural regions. 40% of patients were working. 61% of cases were educated. 58% of cases were smoking tobacco. 12% were alcoholic. 28% of patients wear glasses (Table 1). The most frequent disorder visualized was tritanomaly in 63%, followed by trichromate in 27%, and the least disorder was deuteranomaly in 2%. In addition, mixed disorder is seen in 8% of cases (Table 2). In relation to laterality, right eye tritanomaly was found in 34%, while the left eye was recorded in 29%. The right eye trichromate was observed in 12%, whereas the left eye was reported in 15%. The left eye deuteranomaly was reported more than the right (1.5% vs. 0.5%) ( Table 3).

Discussion
In this study, the most frequent disorder visualized was tritanomaly in 63%, followed by trichromate in 27%, and the least disorder was deuteranomaly in 2%.
In addition, mixed disorder is seen in 8% of cases.  *Deuteranomaly is the most common type of red-green color blindness. Trichromacy or trichromatism is the possessing of three independent channels for conveying color information, derived from the three different types of cone cells in the eye, tritan color blindness confuse blue with green and yellow with violet (blue-green color blindness), Tritanomaly: This is an alleviated form of blue-yellow color blindness, where the S-cones are present but do have some kind of mutation, Tritanopia: People affected by tritanopia are dichromats. This means the S-cones are completely missing, and only long-and mediumwavelength cones are present; **Fisher exact test. Predominantly it is tritanopia, and the type and severity of the defect fluctuate during the disease. 18,19 This study found tritan color defects in DM before clinically visible retinopathy for the prevention of irreversible damage to the retina and thereby support treatment strategies. This can help cases in making professional choices easy whom color vision is affected and help them to overcome further emotional trauma.

Conclusion
Color vision evaluation with good screening color vision test can be detected even before clinically visible diabetic retinopathy. Early detection was helpful in the prevention of vascular changes in the retina. All diabetic patients should be given proper awareness and health education regarding color vision deficiency.
Timely assessment of color vision may detect tritanomaly earlier in diabetics.