3. Blood supply of the brain
The brain is supplied
by 2 systems of
blood:
1- Vertebrobasilar system
2- Carotid system
The 2 systems are connected by
the circulus arteriosus.
4. Blood supply of the brain
The brain is supplied
by 2 systems of
blood:
1- Vertebrobasilar system
2- Carotid system
The 2 systems are connected by
the circulus arteriosus.
6. Vertebral artery
Origin: 1st part of
subclavian artery
Course: ascend through
the foramina transversaria
of the cervical vertebra.
Termination: at the lower
border of pons by uniting
with its fellow to form
basilar artery.
7. Vertebral artery
Branches:
1. Anterior spinal artery: single artery
supply the anterior third of the spinal
cord
2. Two posterior spinal arteries: supply
the posterior third of the spinal cord.
3. Medullary branches: Supply the middle
zone of the medulla.
4. Posterior Inferior Cerebellar Artery
(PICA). It supplies:
a. Dorsolateral zone of the medulla.
b. Posterior part of the inferior surface
of the cerebellum.
c. Choroid plexus of the 4th ventricle.
d. It usually gives the posterior spinal
artery.
8. PICA STROKE
AREA OF LESION SYMPTOMS IMPORTANT NOTES
Nucleus Ambigus (IX, X and
XI)
Dysphagia, Hoarsness,
Hiccups and Depressed Gag
Reflex
Don’t pick a (PICA) horse
(hoarsness) that cant eat
(dysphagia)
Vestibular Nuclei
Vomiting, Vertigo and
Nystagmus
Also called Lateral
Medullary and Wallenburg
Syndrome
Lateral Spinothalamic Tract
and Spinal Trigeminal
Nucleus
Decreased pain and temp
sensation from contralateral
body and ipsilateral face
Cross Sign
Sympathetic fibres and
Inferior cerebellar peduncle
Ipsilateral Horner Syndrome,
Ataxia and Dysmetria
9. ANTERIOR SPINALARTERY
STROKE
AREA OF LESION SYMPTOMS IMPORTANT NOTES
Lateral Corticospinal Tract
Contralateral paralysis of
upper and lower limbs
Also called Medial
Medullary and Dejerine
Syndrome
Medial Lemniscus
Decreased proprioception
contra laterally
Caudal Medulla and
Hypoglossal Nerve
Tongue deviates ipsilaterally
10. Basilar artery
Origin: union of the 2
vertebral arteries at the
lower border of pons.
Course: ascend in the
basilar groove.
Termination: at the upper
border of pons by giving
2 posterior cerebral
arteries.
11. BASILAR ARTERY STROKE
AREA OF LESION SYMPTOMS IMPORTANT NOTES
Pons, medulla and lower
midbrain
Reticular system is spared so
preserved consciousness
Also called Locked In
Syndrome
Corticospinal and
Corticobulbar tracts
Quadriplegia, loss of
voluntary facial, mouth and
tongue movements
Most dreadful stroke
Ocular Cranial Nerve Nuclei
Loss of HORIZONTAL eye
movements. Vertical spared
12. Basilar artery
Branches:
1.Pontine: Paramedian, short &
long circunfrential.
2. AICA: it gives
1. Anterior part of the inferior
surface of crebellum.
2. Middle cerebellar peduncle.
3. Tegmentum of pons.
4. May give labrynthine.
3. Superior cerebellar
4. Labrynthine: in 15%
13. AICA STROKE
AREA OF LESION SYMPTOMS IMPORTANT NOTES
Facial Nucleus
Facial Paralysis (LMN),
decreased lacrimation,
salivation and taste sensation
from anterior 2/3rd of tongue
Also called Lateral Pontine
Syndrome
Vestibular Nuclei
Vomiting, vertigo and
nystagmus
Remember FACIA in AICA
Lateral Spinothalamic Tract
and Spinal Trigeminal
Nucleus
Decreased pain and temp
sensation from contralateral
body and ipsilateral face
Cross Sign
Sympathetic fibres, Middle
and Inferior cerebellar
peduncle
Ipsilateral Horner Syndrome,
Ataxia and Dysmetria
Labyrinthine Artery
Ipsilateral sensorineural
deafness and vertigo
14. Basilar artery
Branches:
1.Pontine: Paramedian, short &
long circunfrential.
2. AICA: it gives
1. Anterior part of the inferior
surface of crebellum.
2. Middle cerebellar peduncle.
3. Tegmentum of pons.
4. May give labrynthine.
3. Superior cerebellar
4. Labrynthine: in 15%
15. Basilar artery
Branches:
1.Pontine: Paramedian, short &
long circunfrential.
2. AICA: it gives
1. Anterior part of the inferior
surface of crebellum.
2. Middle cerebellar peduncle.
3. Tegmentum of pons.
4. May give labrynthine.
3. Superior cerebellar
4. Labrynthine: in 15%
17. Posterior cerebral artery
Origin: Bifurcation of
basilar artery.
Course: curve around the
midbrain to reach the
splenium of corpus
callosum. where it
divides into:-
Calcarine & parieto-
occiptal branches
18. Posterior cerebral artery
Origin: Bifurcation of
basilar artery.
Course: curve around the
midbrain to reach the
splenium of corpus
callosum. where it
divides into:-
Calcarine & parieto-
occiptal branches
19. Posterior cerebral artery
Origin: Bifurcation of
basilar artery.
Course: curve around the
midbrain to reach the
splenium of corpus
callosum. where it
divides into:-
Calcarine & parieto-
occiptal branches
20. Posterior cerebral artery
Branches:
1) Central
a) Medial central branches: supply
thalamus & hypothalamus.
b) Lateral central branches: supply
midbrain.
2) Cortical
- All occipital lobe.
- Lower inch of lateral surface.
- Tenterial surface except the
temporal pole.
3) Splenial:
to the splenium of the corpus
callosum.
21. Posterior cerebral artery
Branches:
1) Central
a) Medial central branches: supply
thalamus & hypothalamus.
b) Lateral central branches: supply
midbrain.
2) Cortical
- All occipital lobe.
- Lower inch of lateral surface.
- Tenterial surface except the
temporal pole.
3) Splenial:
to the splenium of the corpus
callosum.
22. Posterior cerebral artery
Branches:
1) Central
a) Medial central branches: supply
thalamus & hypothalamus.
b) Lateral central branches: supply
midbrain.
2) Cortical
- All occipital lobe.
- Lower inch of lateral surface.
- Tenterial surface except the
temporal pole.
3) Splenial:
to the splenium of the corpus
callosum.
23. POSTERIOR CEREBRAL
ARTERY STROKE
AREA OF LESION SYMPTOMS IMPORTANT NOTES
Occipital Lobe
Contralateral hemianopia
with macular sparing
Alexia without agraphia
(dominant hemisphere)
24. Carotid system
The carotid system is
formed of
1.Internal carotid
artery & its 2 terminal
branches:
2.Anterior cerebral
artery.
3. Middle cerebral
artery.
25. Anterior cerebral artery
Origin: the smaller of 2
terminal branches of
internal carotid artery.
Course: Pass upward and
medially on the genu of
corpus callosum.
Ends at the splenium by
anastomosing with
posterior cerebral
artery.
26. Anterior cerebral artery
Branches:
1. Central: to
A) internal capsule.
B) Anterior part of hvpothalamus.
C) Septum pellucidum.
2. Cortical
Medial surface of frontal and
parietal lobes.
Upper one inch of lateral surface.
Medial half of the orbital surface.
3. Callosal:
to the corpus callosum.
27. Anterior cerebral artery
Branches:
1. Central: to
A) internal capsule.
B) Anterior part of hvpothalamus.
C) Septum pellucidum.
2. Cortical
Medial surface of frontal and
parietal lobes.
Upper one inch of lateral surface.
Medial half of the orbital surface.
3. Callosal:
to the corpus callosum.
28. Anterior cerebral artery
Branches:
1. Central: to
A) internal capsule.
B) Anterior part of hvpothalamus.
C) Septum pellucidum.
2. Cortical
Medial surface of frontal and
parietal lobes.
Upper one inch of lateral surface.
Medial half of the orbital surface.
3. Callosal:
to the corpus callosum.
29. ANTERIOR CEREBRAL
ARTERY STROKE
AREA OF LESION SYMPTOMS IMPORTANT NOTES
Motor and Sensory Cortex
(Lower Limb)
Contralateral paralysis and
sensory loss in lower limb,
urinary incontinence
30. Middle cerebral artery
Origin: the larger of the 2
terminal branches of
internal carotid.
Course: Enters the lateral
sulcus.
31. Middle cerebral artery
Branches:
1. Central: supply posterior limb of
internal capsule.
2. Cortical
A) All temporal pole.
B) Lateral surface of the
hemisphere except:-
- Upper inch.
- Lower inch & occipital lobe
C) Lateral half of the orbital
surface.
32. Middle cerebral artery
Branches:
1. Central: supply posterior limb of
internal capsule.
2. Cortical
A) All temporal pole.
B) Lateral surface of the
hemisphere except:-
- Upper inch.
- Lower inch & occipital lobe
C) Lateral half of the orbital
surface.
33. Middle cerebral artery
Branches:
1. Central: supply posterior limb of
internal capsule.
2. Cortical
A) All temporal pole.
B) Lateral surface of the
hemisphere except:-
- Upper inch.
- Lower inch & occipital lobe
C) Lateral half of the orbital
surface.
34. MIDDLE CEREBRALARTERY
STROKE
AREA OF LESION SYMPTOMS IMPORTANT NOTES
Motor and Sensory Cortex
(Upper Limb and Face)
Contralateral paralysis and
sensory loss in face and
upper limb
Most common
Wernicke Area (Superior
temporal gyrus of temporal
lobe)
Receptive Aphasia
Wernicke is wordy but
makes no sense
Broca Area (Inferior frontal
gyrus of frontal lobe
Expressive Aphasia
Broca is broken. Frustrated
as insight is intact
36. Circulous arteriosus
Definition: It is an
arterial circle connecting
the vertebrobasilar
system with the carotid
system.
Site: in the
interpeduncular fossa in
the base of the brain.
37. Circulous arteriosus
Formation: by the following
arteries:
1. Anteriorly: anterior communicating
artery connecting the two anterior
cerebral arteries.
2. Posteriorly: two posterior cerebral
arteries (bifurcation of the basilar
artery).
3. On each side:
a. Anterior cerebral artery.
b. Proximal part of the internal
carotid artery.
c. Posterior communicating artery.
38. Circulous arteriosus
Importance:
1. It forms a communication between the
vertebrobasilar system and the carotid
arteries.
2. It forms a communication between the
arteries of the two sides.
3. Since blood pressure is equal in the arteries
of the circle, mixing of the blood does not
occur.
4. Provide a collateral circulation in case of
occlusion of any artery in the circle.
5. It acts as a safety valve to equalize
pressure between the major arteries.
NB The circle is a common site of a disease
named arterial aneurysm (aneurysm is a local
dilatation in the wall of arteries).
