DR Medhat MRCP

Middle cerebral artery (MCA)
• Origin : One of the 2 terminal branches of internal carotid artery.
• Areas supplied : ( anterior 3/5 of lateral surface of cerebral hemisphere)
o Lower part of cortical motor area (UL area).
o Lower part of cortical sensory area 1,2,3 (UL area).
o Optic radiation (both upper fibers in parietal L & lower fibers in temporal L).
o Auditory associative area (=area 22=Wernicke`s area)
o Frontal eye field area (area 8) [area of conjugate eye mov. to opposite side]
o Exner`s area (area 45)[area of writing].
o Posterior 1/5 of internal capsule.
• Middle cerebral artery occlusion (stroke) :
1. Contralateral hemiparesis & sensory loss (UL >LL).
2. Contralateral homonymous hemianopia .
3. Aphasia (Wernick`s or receptive > motor or expressive )(in left sided lesion)
4. Auditory agnosia.
5. Gaze abnormalities (loss of conjugate eye movement to the opposite side).
6. Agraphia (in left sided lesion)
Vertebro-basilar (posterior ) system :
Vertebral artery
• Origin : from subclavian artery on both sides at the level of C6 vertebra.
• Course :
- Ascends upwards inside the transverse foramina of upper 6 cervical vertebrae
then enter the skull through foramen magnum then pierces the dura matter &
arachnoid matter to enter the sub-arachnoid space ) ‏)هام then joins its fellow of
the other side at the ponto-medullary junction to form basilar artery.
• Branches :
1. Posterior inferior cerebellar (PICA) artery : to posterior part of inferior surface
of cerebellum & lateral medulla
2. Anterior spinal artery : to anterior 2/3 of spinal cord.
3. Posterior spinal artery : to posterior 1/3 of spinal cord.
4. Medullary branches. To medulla.
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