Inclusion Criteria:  Patients at least 18 years of age At least one documented, intradural, intracranial aneurysm anywhere on the course of the MCA vessel, ruptured or unruptured. An untreated ruptured aneurysm (with delay in diagnosis) which is suspected to have occurred more than 30 days prior to study inclusion will be considered an unruptured aneurysm In the case of SAH, WFNS grade 4 or less The patient and aneurysm are considered appropriate for either surgical or endovascular treatment by the treating team  Exclusion Criteria:  Patients with absolute contraindications administration of contrast material (any type) Patients with AVM-associated aneurysms Patients or caregivers unable to provide consent Poor grade (WFNS 5) ruptured aneurysms