Most IIAs are caused by bacterial infection, most commonly Staphylococcus aureus and Streptococcus species. In most cases the infection originates from left-sided bacterial endocarditis. Other common sources include cavernous sinus thrombosis, bacterial meningitis, poor dental hygiene and intravenous drug use. The use of the term<unk>  aneurysm by the above authors is incorrect. Refer to Holtzman RNN, Pile-Spellman JMD, Brust JCM, Hughes JEO, Dickinson PCT: Surgical Management of Intracranial Aneurysms Caussed by Infection, in: Schmidek HH and Roberts DW(eds): Schmidek & Sweet Operative Neurosurgical Techniques: Indications, Methods, and Results ed.5. Philadelphia: Elsevier Inc. 2006 Vol 1: Chap. 87, pp1223-1259
Infectious intracranial aneurysm
Cerebral vasculitis
Intracranial aneurysm
Cerebral atherosclerosis
Cerebral venous sinus thrombosis
Cirsoid aneurysm
Cerebral arteriovenous malformation
Carotid artery dissection