Cerebral Blood Flow (CBF)=(MAP - ICP)/CVR
MAP(Mean art press)= DBP+[1/3(SBP-DBP)]
Where,
ICP=intracranial press
CVR = Cerebral Vascular Resistance (units are dynes = mmHg/mL/min)
Within the limits of systemic MAP, the human brain alters CVR to keep CBF constant.
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