Location, Infarct Load, and 3-Month Outcomes of Delayed Cerebral Infarction After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND AND PURPOSE: Aneurysmal subarachnoid hemorrhage is a serious disease with high case fatality and morbidity. Delayed cerebral infarction (DCI) is an important surrogate marker. How location and infarct load affected outcomes was unclear. We aimed to assess the effects of load and location of DCI on outcomes of aneurysmal subarachnoid hemorrhage at 3 months. METHODS: We prospectively enrolled patients with subarachnoid hemorrhage presenting to an academic neurosurgical unit in Hong Kong during a 3-year period. DCI was defined by new hypoattenuation on computed tomography at 4 to 6 weeks, which was not present in the postaneurysm-treatment computed tomography at 24 to 48 hours. DCI was assessed for location according to cerebral artery territories and load semiquantitatively. Cognitive and functional outcome assessments were carried out 3 months after ictus. RESULTS: One hundred twenty-six patients with subarachnoid hemorrhage consented for this study. DCI occurred in 56 (44%) patients and was associated with poorer cognitive and functional outcomes (Montreal Cognitive Assessment, Mini-Mental State Examination, modified Rankin Scale, and Lawton Instrumental Activity of Daily Living) at 3 months. In patients with DCI, the presence of perforator zone infarct was associated with poorer cognitive and functional outcomes, and cortical middle cerebral artery infarct was associated with poorer modified Rankin Scale. After adjustment for age, admission World Federation of Neurosurgical Societies Grade and mode of aneurysm treatment, both middle cerebral artery cortical infarct load and perforator infarct load were independently associated with poor cognitive outcomes (Montreal Cognitive Assessment and Mini-Mental State Examination) and modified Rankin Scale. CONCLUSIONS: Middle cerebral artery cortical and perforator zone infarct loads are potential surrogate marker to assess the severity of delayed cerebral ischemia.