Prevalence of color-vision deficiency among male high-school students

@#Objective This study determined the prevalence of color-vision deficiency among male high-school students in a public school. Methods Male high-school students were screened for color-vision deficiency using 6 plates of the Ishihara pseudoisochromatic plates. All students with one or more errors were reexamined at a later date with the full 15 Ishihara plates and the Farnsworth D15 (FD15) test. A detailed history was taken and an ocular examination was conducted. Students who identified less than 10 plates correctly on the FD15 were classified as color-deficient and underwent the Farnsworth Munsell 100 hue (FM 100) test. The results were statistically analyzed. Results A total of 1,258 male high-school students, aged 12 to 16 years, were included in the study, 122 of whom failed the screening test. Of these, 106 completed the 15 Ishihara plates. Sixty-five failed and were classified as color-visiondeficient, of which 64 (98%) were deutans. Deutan was also the most common deficiency determined using the FD15 (78.95%) and FM100 (44.19 %) hue tests. Conclusion The prevalence of color-vision deficiency among male students in a public high school was 5.17% (65/1,258). The most common deficiency was the deutan type.

Color-vision abnormalities among patients undergoing tuberculosis treatment

Objective@#This study determined the incidence of and risk factors for color-vision abnormalities among Filipino patients undergoing directly observed treatment short-course (DOTS) for tuberculosis.@*Methods@#A prospective single-cohort study involving newly diagnosed patients with category-1 tuberculosis, recruited from DOTS health centers in Manila, was conducted. All patients were given a fixed-dose combination of rifampicin, isoniazid, ethambutol, and pyrazinamide for 60 days, after which treatment was continued with rifampicin and isoniazid for 4 more months. The participants underwent complete eye evaluation including color-vision testing and were followed up every month up to the conclusion of treatment.@*Results@#Out of 93 patients initially enrolled, 64 completed the prescribed follow-up and constituted the study group. Baseline color vision was normal. After 1 month of therapy, color vision tested with the Ishihara plates remained normal in all patients, but one failed the Farnsworth Panel D 15 and was classified as tritan while 30 (47.88%) failed the Lanthony Desaturated test. The type of abnormality was unclassified in 20 (66.67 %)patients and tritan in 10 (33.3%). Visual acuity remained unchanged from baseline. Repeat testing after ethambutol and pyrazinamide were stopped showed that color vision was normal using the Ishihara plates and the Farnsworth test, while 5 failed the Lanthony test. Of these, 3 were unclassified and 2 were tritan. In the 3rd to 6th months follow-up, no color-vision abnormalities were noted in the 3 tests. The only risk factor identified was age (p = 0.01) with older patients having a higher risk.@*Conclusion@#The incidence of color-vision abnormalities among patients undergoing DOTS was 47.88% using the Lanthony Desaturated test after an average of 39.66 days on quadruple anti-TB therapy. Age was the only significant risk factor observed. The color-vision abnormalities returned to normal within an average of 37.85 days after discontinuing ethambutol and pyrazinamide.