Abstract
Purpose: :
Lipid apheresis is used to treat patients with refractory hyperlipidemia. Single LDL apheresis treatment has shown to improve blood and plasma viscosity, red cell aggregation and deformability. Therefore, the aim of the present study was to investigate the effect of lipid apheresis on ocular microcirculation.
Methods: :
6 patients with refractory hyperlipidemia were included in this study. The diameter of retinal vessels was measured continuously with the retinal vessel analyzer (RVA) 30 minutes before and 30 minutes after LDL apheresis. After baseline assessment a monochromatic luminance flicker (530-600nm; 12,5Hz; 20s) was applied to evoke retinal vasodilation. Flicker response was then analyzed 50, 70 and 120 sec after baseline measurement.
Results: :
The mean diameter of the arteries at baseline was 107.5 +/-2.08 µm and the mean diameter of the venes was 132.7 +/- 3.2 µm. The vascular calibre of the arteries after apheresis increased from 105.5 +/- 2.6 µm to 112.1 +/- 5.8 µm after 50 sec, from 107.7 +/- 2.6 µm to 116.7 +/- 9.9 µm after 70 sec and from 110.8 +/- 5.5 µm to 139.2 +/-2.9 µm after 120 sec which was statistically significant at all time points (P < 0.005, P < 0.001 and P < 0.0001). The vascular calibre of the venes after apheresis increased from 133.8 +/- 3.01 µm to 140.0 +/- 5.0 µm after 50 sec, from 136.4 +/- 3.1 µm to 145.0 +/- 5.7 µm after 70 sec and from 138.5 +/- 4.0 µm to 155.9 +/-3.3 µm after 120 sec which was statistically significant at all time points, too (P < 0.005, P < 0.001 and P < 0.0001).
Conclusions: :
Changes in retinal vascular calibre seem to be associated with the effect of systemic LDL apheresis. Despite a small study population, vasodilatation of arteries and venes significantly improved after LDL apheresis demonstrating a significant improvement of ocular perfusion in patients with refractory hyperlipdemia.
Keywords: retina • image processing • optic flow