Table 3. Annual rupture risk of UIA without "previous episode of SAH" of not-treated group according to size and location.
UIA : unruptured intracranial aneurysm, SAH : subarachnoid hemorrhage, No. : number, MCA : middle cerebral artery, ACoA : anterior communicating artery, ICA : internal carotid artery, PCoA : posterior communicating artery