Cerebral Blood Flow : CBF is explained as the blood volume that flows per unit mass per unit time in brain tissue and is typically indicates in units of ml blood. Direct methods for calculating CBF in human subjects include single-photon emission computed tomography (SPECT), positron emission tomography (PET), MRI with contrast agents, and arterial spin labeling (ASL) MRI.
CBF is controlled by four major mechanisms:
Metabolism: Metabolism is used to express all chemical reactions included in continuing the living state of the cells and the organism. Metabolism can be efficiently divided into two categories: Catabolism and Anabolism. Catabolism refers to the breakdown of molecules to obtain energy and Anabolism refers to the synthesis of all compounds needed by the cells.