<Li> Increased ICP compresses cerebral arteries, causing increased cerebrovascular resistance (CVR). </Li> <P> Cerebral perfusion pressure, or CPP, is the net pressure gradient causing cerebral blood flow to the brain (brain perfusion). It must be maintained within narrow limits because too little pressure could cause brain tissue to become ischemic (having inadequate blood flow), and too much could raise intracranial pressure (ICP). </P> <P> Functional magnetic resonance imaging and positron emission tomography are neuroimaging techniques that can be used to measure CBF . These techniques are also used to measure regional CBF (rCBF) within a specific brain region . rCBF at one location can be measured over time by thermal diffusion </P>

What are the arteries that supply blood to the brain