Decerebrate posture following bilateral middle cerebral artery occlusion.

The most common cause of decerebrate posture is brain damage at the level of the brain stem. However, decerebration could occur without any brain stem damage by occlusion of both carotid arteries (1, 2). A 60-year-old man was admitted to the hospital because of loss of consciousness while working, immediately followed by decerebrate extensor posture. An electrocardiogram showed atrial fibrillation. The pupils were 2.0 mm in diameter and symmetrically reactive to light. There was no evidence of posterior circulation infarcts. Brain computed tomography without contrast enhancement showed hyperdense bilateral middle cerebral arteries (Picture 1 A, arrows). Axial diffusion-weighted magnetic resonance image showed restricted diffusion in the territory of bilateral middle cerebral arteries (Picture 1 B). It has been reported that three of six patients with acute bilateral internal carotid artery occlusion presented with decerebrate posture (2). Simultaneous occlusion of bilateral middle cerebral arteries by catastrophic cardioembolism can cause decerebrate posture in humans.