The hemodynamics of the brain are frequently expressed in terms of three variables:-
CBV (cerebral blood volume) is the amount of blood in a certain amount of brain tissue, usually measured in milliliters per 100 g of brain tissue.
CBF (cerebral blood flow) or perfusion is a measurement of the rate at which arterial blood is delivered to a capillary bed in the brain tissue.
CMRO2 (cerebral metabolic rate of oxygen): The cerebral metabolic rate of oxygen (CMRO2) is the rate at which the brain consumes oxygen and is considered a direct indicator of energy equilibrium and brain health.
The cerebral oxygen extraction fraction (COEF) is also considered at times.