1. Anatomy: Vascular Variants

Question 1

Most common Vascular variant?

Answer 1

Fetal Origin of the PCA

PCA is fed primarilty as an anterior circulation artery (Occipital lobe is fed by the ICA)

Therefore, PCOM is large

PCOM superor/lateral to CN3 (Instead of superior medial-normal anatomy)

Question 2

Persistent Trigeminal Artery

Answer 2

Persistent fetal connection between cavernous ICA to the basilar

“TAU” sign

Increased risk of Aneurysm