椎骨脳底動脈灌流領域脳卒中における超急性期治療志向性迅速診断

抄録

　　For patients presenting to the ER or clinics with sudden onset of vertigo and dizziness, immediate medical attention for suspected stroke is critical, as immediate treatment can minimize the long-term functional outcome after stroke and prevent death. Patients with cerebellar or brainstem stroke because of compromised vertebral and/or basilar arterial supply often present not only with vertigo/dizziness and nystagmus, but also with dysarthria/dysphagia, ataxia, disturbed consciousness, restriction of eye movements and hemiparesis. There are two broad types of stroke: hemorrhagic and ischemic. An ischemic stroke occurs as a result of obstruction of the blood vessel supplying blood to the brain. Atrial fibrillation can cause cardiogenic embolism, and the risk factors such as hypertension, diabetes, dyslipidemia and smoking induce arterial occlusion to lead to atherothrombotic or lacunar infarction. Hemorrhagic stroke occurs when a weakened blood vessel ruptures and blood leaks into the cerebellum and brainstem. The most common cause of such blood vessel rupture is uncontrolled hypertension or anti-thrombotic treatment. CT and MRI with diffusion-weighted imaging and MR angiography play critical and essential roles in the definitive diagnosis of ischemic or hemorrhagic stroke. The gold standard treatment for ischemic stroke is administration of a tissue plasminogen activator (t-PA) by intravenous injection via through vein in the arm. The t-PA works by dissolving the clot and improving the blood flow to the part of the brain that is deprived of blood flow. If administered within 4.5 hours of the onset, t-PA may improve the chances of complete recovery from a stroke. Another treatment option is an endovascular procedure called mechanical thrombectomy using the stent or suction after detection of the ischemic penumbra by MRI. To attenuate the brain damage caused by the intraparenchymal hematoma and its expansion, intensive blood-pressure lowering, optional hemostasis against anti-thrombotic agents or surgical removal of the hematoma could be performed immediately after serial CT. The concept that “Time is Brain” in the treatment strategy of acute stroke strongly depends upon quick triage for stroke using the A²B²C²D² score, and an attempt at immediate diagnosis based on an accurate medical history for ABC-DEMON, neurological examination, immediate CT followed by MRI, and face-to-face cooperation and collaboration between specialists in otorhinolaryngology and cerebrovascular neurology.