Cerebello-Pontine angle tumors

Tumors at the CP angle compress CN VII and VIII, together with the pyramid and cerebellum.  They present with CN VII/VIII defects together with motor deficits.

Interpenduncular fossa tumors may compress the:

a) Hypothalamus
b) Oculomotor nerve
c) Crus Cerebri

The circle of willis is a frequent site of berry aneurysms