Acute baseline CT scans will be collected (standard of care). All patients will have MRI including susceptibility weighted imaging after recruitment within the first 24 hours and a follow-up MRI scan 7±2 days after enrolment, in order to assess for early asymptomatic hemorrhagic transformation. In the event of any clinical deterioration, a repeat CT scan will be performed immediately. The investigators hypothesize micro-hemorrhages may predict symptomatic bleeding. In addition, any supplemental brain imaging completed within the first 30 days after enrolment will be collected.