Perfusion MRI study. Left: Cerebral blood flow (CBF) in a 33-year-old, relapsing-remitting (RR) chronic cerebrospinal venous insufficiency (CCSVI) multiple sclerosis (MS) patient with a venous hemodynamic insufficiency severity score (VHISS) of 5. Right: CBF in a 38-year-old, RR CCSVI-MS patient with a VHISS of 12. The dark areas indicate lower CBF in the patient with higher VHISS.
Zamboni et al. BMC Medicine 2011 9:22 doi:10.1186/1741-7015-9-22