It is known that the clot busting agent (Alteplase), the main effective treatment used in the acute stroke can only improve blood flow in already blocked arteries in 50% of patients. Therefore, as well as attempts to treat blockage of major vessel, improving the blood flow through vessel that bypass the blocked vessel around the stroke area (penumbra) could be another potential therapeutic approach in acute ischaemic stroke patients. A simple way of increase blood flow to these penumbral area might be just lower the head of acute stroke patients into a lying flat position. Several observational studies have investigated the effects of head positioning on blood flow to the brain in a healthy population, however few studies carried out on acute ischaemic stroke patients so far.