Abstract
Abstract: :
Purpose: To study vasomotion in large retinal arterioles from normal persons and diabetic patients with varying degree of diabetic maculopathy using the retinal vessel analyzer (RVA). Previous experiments have shown a difference in the frequency of vasomotion between arterioles leading to an area with CSMO in diabetic patients and arterioles of similar size in healthy volunteers. The aim of this study was to compare the frequency of vasomotion of large retinal arterioles in diabetic patients with varying degrees of maculopathy and in healthy volunteers using a non–invasive device, the retinal vessel analyser (RVA, Imedos, Germany). Method:Twenty–one type 2 diabetic patients and seven normal persons were studied. The diabetic patients consisted of three groups matched for age, gender and diabetes duration characterized by A) macular oedema not requiring laser treatment, B) mild retinopathy consisting of one to four microaneurysms, C) no retinopathy. The normal persons were matched with respect to age and gender. The diameter changes of a retinal arteriole was measured continuously over a 3–minute period at a first order retinal arteriole using the RVA. The diameter measurements were analyzed by fourier transformation and the most prominent peak in the frequency domain and the corresponding amplitude among the four groups were compared using one–way ANOVA. Results: There was no significant difference between the peak frequency of vasomotion (3.9±2.0, 2.6±2.7, 2.9±1.7, 3.4±1.9, (mean±SD) group A to D, respectively) or the amplitude among the four groups (p=0.68 and p=0.79, respectively). Conclusion:The lack of relation between diabetic maculopathy and vasomotion frequency in large retinal arterioles is in contrast to previous studies where such a relationship has been found in smaller retinal arterioles. This suggests that changes in vasomotion of smaller but not larger retinal arterioles may be involved in the pathogenesis of diabetic maculopathy.
Keywords: diabetic retinopathy • retina • blood supply