Internal Carotid System

Question 1

Origin

Answer 1

In neck as one of 2 terminal branches of common carotid artery CCA, opposite disc between C3 and C4

Question 2

Course

Answer 2

1. Enters skull through carotid canal
2. Reach cavernous sinus
3. Leaves cavernous sinus
4. Pierce dura and arachnoid maters
5. Reach subarachnoid space in Interpeduncular cistern

Question 3

Branches and supply

Answer 3

1. Ophthalmic artery: orbit
2. Posterior communicating artery join posterior cerebral artery sharing in circulus arteriosus formation
3. Anterior choroidal artery
4. Anterior cerebral artery
5. Middle cerebral artery

Question 4

End

Answer 4

Terminates below anterior perforated substance by dividing into 2 terminal branches:
1. Anterior cerebral artery (small)
2. Middle cerebral artery (large and nearly in direct line with ICA main trunk)

Question 5

Anterior choroidal artery course

Answer 5

Passes backwards along optic tract around cerebral peduncle lateral surface as far as lateral geniculate body

Question 6

Anterior choroidal artery end

Answer 6

By entering lateral ventricle inferior horn (in its medial wall) through choroidal fissure lower part

Question 7

Anterior choroidal artery supply

Answer 7

1. Optic tract
2. Lateral geniculate body
3. Choroid plexus
4. Internal capsule:
   - Posterior part of posterior limb part
   - Retrolentiform part
   - Sublentiform part