I am a Neurosurgeon with advanced training in Interventional vascular Neurosurgery(FINR) from Zurich, Switzerland, and FMINS-Fellowship in minimally invasive and Endoscopic Neurosurgery from Germany. I am presently working in Columbia asia hospitals, Bangalore. My areas of interest are Vascular Neurosurgery, Stroke specialist, interventional neuroradiology, Endoscopic and minimally invasive Neurosurgery, Endoscopic spine surgery.

1. Anatomy & Blood supply
of the brain
Dr. Avinash KM
MS, MRCS Ed(UK), Mch (KEM, Mumbai), FINR(Switzerland), FMINS(Germany),
• Interventional & Neurovascular surgeon and Stroke specialist,
• Endoscopic Neuro and Spine surgeon,
• Minimally invasive Neuro and Spine surgeon (FMINS).
mob: 9740866228, E mail: doc_avin@hotmail.com
Consultant Neurosurgeon and Neurointerventionist
Columbia Asia Hospital, Bangalore.

2. Blood supply to brain
• Healthy young adults have brain size of 1300 to 1400 grams and
have an average whole brain blood flow of approximately 46 mL/100 gram of
brain /minute.
• The brain comprises only 2% of body weight, but receives 15% of
cardiac output and uses 20% of total body oxygen and 25% of total
body glucose.
• In newborn infants, mean global CBF is low, ranging from 6 to
35 mL/100 g /min. Global oxygen utilization in the normal newborn is
also very low, with the majority of values less than 1.3 mL/100 g/min.
This finding indicates that energy requirements in fetal and newborn
brain are minimal.
• Beyond the neonatal period, global CBF, oxygen and
glucose utilization progressively increase, reaching a maximum at
age 3-10 years (60 to 140 mL/100 g /min , oxygen ranging from 4.3 to
6.2 mL/100 g/min, and Glucose ranging from 49 to 65 μ mol/100 g/min).
• By late adolescence, cerebral flow and oxygen and glucose
metabolism decrease to adult levels.

3. Blood supply to brain
•The blood vessels supplying brain
are two internal carotid arteries and
two vertebral arteries.
•Carotid artery contributes
approximately 80% to the total
cerebral blood flow, the remaining
20% coming from the two vertebral
arteries
Pulsations felt when one keeps hand over neck are actually carotid pulsations

4. Blood supply of Brain
Blood vessels seen from below

5. Blood supply of the brain
Blood vessels when seen from front of brain

6. Blood supply of the brain
Blood vessels seen from side
Blood vessels seen from inner
side of hemisphere

7. Blood supply of Brain stem

8. What happens when blood supply
to brain is reduced?
• Certain functional changes occur once blood flow to the brain
decreases. Critical values for loss of synaptic transmission,
corresponding to loss of neuronal function, are between 15 and
18 ml/100 gram/minute.
• The threshold for membrane pump failure. and thus for loss of
cellular integrity and cell death, is approximately 10 ml/100
gram/ minute.
• It is generally assumed that if CBF stays above 18 ml/100 g/min
but below 20–25 ml/100 g/min neurons will survive but may
not function.