Rheopheresis is a process to change the viscosity of blood by filtering blood to remove some components such as fibrinogen, von Willebrand factor and LDL cholesterol.
It is experimental treatment for dry age-related macular degeneration (AMD) and Acute Ischemic Stroke
Some trials have given disappointing results for AMD but two German studies (72 and 43 patients) reported good results in 2009
References
Rheopheresis Wikipedia(Text) CC BY-SA