Chapter 22: The Neuropsychiatry of Stroke

INTRODUCTION

Stroke is the fifth leading cause of death in the United States and an important cause of disability. Every year, about 795,000 people in the United States have a stroke. About 610,000 of these are first or new strokes; 185,000 are recurrent strokes.¹ Stroke is characterized by the sudden occurrence of a neurologic deficit or syndrome. Typically, especially as it pertains to physical symptoms, the resultant neurologic syndrome corresponds to the portion of the brain supplied by the respective cerebral vessels affected by the stroke (see Figures 22-1 and 22-2). Strokes are broadly categorized as ischemic or hemorrhagic.² The underlying cause of the vascular occlusion in ischemic strokes may be: (i) atherosclerosis with superimposed thrombosis, affecting large cerebral or extracerebral blood vessels (Figure 22-3), (ii) cerebral embolism, and (iii) occlusion of small cerebral vessels within the parenchyma of the brain. Alternative pathologic processes that may result in ischemic brain damage include arterial dissection, inflammatory conditions such as vasculitis, thrombosis of cerebral veins, and dural sinuses, thrombosis of cerebral vessels due to hypercoagulable conditions, vasospasm, and other mechanisms. Hemorrhagic strokes (Figure 22-4) are caused by the rupture of blood vessels and subsequent bleeding into the brain parenchyma (intracerebral hemorrhage) or the subarachnoid space (Figure 22-5). Contributing factors to hemorrhagic strokes are weakened blood vessels, for instance due to aneurysms or arteriovenous malformations, and hypertension. Hemorrhagic strokes typically do not respect vascular territories and thus may result in more complex syndromes.