Reducing the temperature of tissue or organs (hypothermia) produces a protective state, through multiple molecular mechanisms, against adverse effects that arise from disrupted organ blood flow, e.g. in acute ischemic stroke (AIS). AIS is often caused by a blood clot that occludes a brain artery which, in turn disrupts brain blood flow. In large vessel occlusions, the current standard includes mechanical thrombectomy (MT), a minimally-invasive procedure that aims at removing the clot via endovascular means. In this case, brain cooling can lead to protection (neuroprotection) not only from the adverse effects of stroke/ischemia itself, but also from complications arising from sudden re-opening of the blocked artery through primary treatment, MT. This potential complication of MT is called reperfusion injury. In this first-in-human investigational deivce study, Hybernia Medical's endovascular brain cooling system will be applied in acute ischemic stroke patients undergoing MT. Post-MT, selective brain hypothermia will be induced and maintained over 30 minutes. Endpoints of this study include, clinical safety, device performance/usability, and clinical outcome.