Cerebral Veins Anatomy

Arterial Supply of the Brain and Spinal Cord

• The brain is supplied by two systems: the vertebrobasilar system (two vertebral arteries and the basilar artery) and the internal carotid system (two internal carotid arteries)

Vertebrobasilar System

• Composed of two vertebral arteries and the basilar artery
• Vertebral artery:
  • Origin: first part of the subclavian artery
  • Course: 4 parts
  • Branches: anterior spinal artery, posterior spinal artery, medullary branches, posterior inferior cerebellar artery (PICA), posterior meningeal artery
  • Termination: unite to form basilar artery at the lower border of the pons
• Basilar artery:
  • Origin: union of the two vertebral arteries at the lower border of the pons
  • Course: ascends in the basilar groove of the pons
  • Branches: pontine branches (3 groups), anterior inferior cerebellar artery (AICA), labyrinthine, superior cerebellar artery, two terminal branches (posterior cerebral arteries)
  • Termination: divides into 2 posterior cerebral arteries at the upper border of the pons

Internal Carotid System

• Composed of two internal carotid arteries
• Internal carotid artery:
  • Origin: one of the two terminal branches of the common carotid artery at the upper border of the thyroid cartilage
  • Course: divided into 4 parts: cervical part, petrous part, cavernous part, and supracavernous part
  • Branches: caroticotympanic, hypophyseal branches, ophthalmic artery, posterior communicating artery, anterior choroidal artery, two terminal branches (anterior cerebral artery and middle cerebral artery)
  • Termination: divides into anterior and middle cerebral arteries lateral to the optic chiasma

Branches of the Internal Carotid Artery

• Cortical branches
• Central branches
• Callosal branches to the entire corpus callosum

Posterior Cerebral Artery

• Origin: bifurcation of the basilar artery at the upper border of the pons
• Course: passes backward around the lateral side of the midbrain to reach the splenium
• Branches: cortical branches, central branches, splenial artery (supplies the splenium)

Venous Drainage of the Brain

• Superficial cerebral veins:
  • Middle cerebral vein
  • Inferior cerebral vein
• Deep cerebral veins:
  • Two internal cerebral veins
  • Great cerebral vein
  • Two basal veins
  • Anterior cerebral vein
  • Middle cerebral vein
  • Basal vein
  • Great cerebral vein
  • Straight sinus

Arterial Supply of the Spinal Cord

• Derived from:
  • Single midline anterior spinal artery (supplies anterior 2/3 of spinal cord)
  • Two posterior spinal arteries (supply posterior 1/3 of spinal cord)
  • Radicular arteries (paired anterior and posterior radicular arteries)
• Radicular arteries originate from spinal branches of vertebral, deep cervical, posterior intercostal, and lumbar arteries