10. Virchow–Robin space
Virchow–Robin spaces (VRS), also
known as perivascular spaces, are
the immunological spaces between
the arteries and veins (not
capillaries) and pia mater that can
be expanded by leukocytes.
20. CEREBRAL PERFUSION PRESSURE
• CPP can be defined as the pressure gradient
causing cerebral blood flow (CBF) such that
• CBF = CPP/CVR
• CVR is cerebrovascular resistance
• An alternative definition of CPP is
• CPP=MAP-ICP where:
– MAP is mean arterial pressure
– ICP is intracranial pressure
21. REGULATION OF CEREBRAL BLOOD FLOW
• Metabolic regulation
• Auto-regulation of CBF
• ICP in regulation of CBF
– Monro Kellie Doctrine
– Cushing reflex
• Nervous regulation of CBF
25. Monro-Kellie doctrine
Brain tissue and spinal
fluid are essentially
incompressible, the
volume of blood, spinal
fluid, and brain in the
cranium at any time must
be relatively constant.
26. Cushing Reflex
• Cushing's triad of
– increased blood pressure,
– irregular breathing,
– reduction of the heart rate
28. REGULATION OF CEREBRAL BLOOD FLOW
• Metabolic regulation
• Auto-regulation of CBF
• ICP in regulation of CBF
– Monroe Kellie Doctrine
– Cushing reflex
• Nervous regulation of CBF
29. Stroke
Stroke, also known as
cerebrovascular accident
(CVA), cerebrovascular
insult (CVI), or brain attack,
is when poor blood flow to
the brain results in cell
death.