Middle cerebral aery syndrome is a condition whereby the blood supply from the middle cerebral aery (MCA) is restricted, leading to a reduction of the function of the poions of the brain supplied by that vessel: the lateral aspects of frontal, temporal and parietal lobes, the corona radiata, globus pallidus, caudate and putamen. The MCA is the most common site for the occurrence of ischemic stroke. Depending upon the location and severity of the occlusion, signs and symptoms may vary within the population affected with MCA syndrome. More distal blockages tend to produce milder deficits due to more extensive branching of the aery and less ischemic response. In contrast, the most proximal occlusions result in widespread effects that can lead to significant cerebral edema, increased intracranial pressure, loss of consciousness and could even be fatal. In such occasions, mannitol (osmotic diuretic) or hypeonic saline are given to draw fluid out of the edematous cerebrum to minimise secondary injury. Hypeonic saline is better than mannitol, as mannitol being a diuretic will decrease the mean aerial pressure and since cerebral perfusion is mean aerial pressure minus intracranial pressure, mannitol will also cause a decrease in cerebral perfusion. Contralateral hemiparesis and hemisensory loss of the face, upper and lower extremities is the most common presentation of MCA syndrome. Lower extremity function is more spared than that of the faciobrachial region.The majority of the primary motor and somatosensory coices are supplied by the MCA and the coical homunculus can, therefore, be used to localize the defects more precisely. Middle cerebral aery lesions mostly affect the dominant hemisphere i.e. the left cerebral hemisphere Ref Harrison20th edition pg 2456