Abstract
Abstract: :
Purpose: Colour vision is altered in 50% of diabetic patients, with or without diabetic retinopathy. Age, macular edema, diabetic retinopathy or neovascularization are associated to the presence of colour vision changes. Some authors think that there is some relationship between the progression of diabetic retinopathy and colour vision alterations (Greenstein 1990). However, there are few research works that define the cause of impaired colour vision in diabetic patients. Our first topic is to define the relationship between ocular signs of diabetes and colour vision alteration in diabetic patients. Methods: 54 eyes of 27 randomized diabetic patients (14 males, 13 females) 4985 (mean dt) years old (11 to 85). Mean years being diabetic were 149 años, 68% using insuline, 8% oral antidiabetics and 24% diet to control glucosa levels. 40% had good metabolic control, 30% regular, 4% poor and 4% not know or not respond. Clinical protocol was made by visual acuity measure (far and near), computed refraction, Farnsworth test (28 hue), IOP and ophthalmoscopy with midriatic pupil. All patients received written information, and informed consent was obtained (Clinical Research Ethics Committee University of Valladolid). Results: Mean far visual acuity corrected was 0,70,3 and near 0,90,2. Mean spherical equivalent was -0,902,8 dp (-8,30 to +5,40). In 30% (IC 95%, 12-47%) was found diabetic retinopathy (Type I: 26%; type II: 2%; type III: 2% and proliferative: 0%). Colour vision was alterated in 67% (IC 95%, 45-80), there were 43% tritan, 24% tertan, 33% inespecific alteration and no found protan or deutan type. There were significative relationship (p<0.01) between colour vision alterations with age and cataracts. In patients younger 50 years old colour visión was impaired in 29% and in patients older 50 years old colour visión was impaired in 83% (p<0.05). There weren´t significative relationship between colour visión alteration and diabetic retinopathy. Conclusion: Accelerated yellowings of the lens in diabetic is the predominant cause of the colour vision anormaly found in diabetic patiens.
Keywords: 387 diabetes • 362 color vision • 378 crystallins