Complex middle cerebral artery aneurysms include aneurysms that are sizeable (large or giant), broad-necked, fusiform, dissecting or serpentine.
They may present with intracranial hemorrhage, mass effects, epilepsy or cerebral ischemia; in addition, the aneurysm may be incidentally discovered.
A high mortality rate of 65–85 % within 2 years (because of rupture or re-rupture) has been reported 1) 2) 3) 4).
Aneurysm rupture survivors are often left with severe neurological deficits.