Special report from the National Institute of Neurological Disorders and Stroke. Classification of cerebrovascular diseases III.

The purpose of this Classification of Cerebrovascular Diseases III is to delineate the types of cerebrovascu-lar disease in clinical and pathological terminology so that all or any portion of the classification may be used by clinicians, surgeons, pathologists, or physiatrists as well as by other groups interested in the subject. It is also intended to define clinical and pathological diagnostic terms for common use. The background material is intended as supporting information for the clinical and pathological classifications. The second Ad Hoc Committee on Cerebrovascular Diseases 1 developed a classification, published in 1975, that provided a clinical and pathological framework for cerebrovascular diseases at that time. The Classification and Outline of Cerebrovascular Diseases II was published near the beginning of an explosion in technological developments that have dramatically enhanced our capability to evaluate patients with these disorders. Technological advances will continue, but the present Classification of Cerebrovascular Diseases III and background material reflect the current state of our knowledge. By the term "cerebrovascular diseases" we refer to all disorders in which there is an area of brain transiently or permanently affected by ischemia or bleeding and/or in which one or more blood vessels of the brain are primarily impaired by a pathological process. The terms "cerebrovascular" and "cerebral" are used in the original Latin sense, referring to the entire brain and not merely to the hemispheres of the forebrain. The term "stroke" is commonly used as a generic term to represent any one or all of a group of disorders, including cerebral infarction, intracerebral hemorrhage, or subarachnoid hemorrhage. The background material supporting the Classification of Cerebrovascular Diseases III recognizes the potential impact of preventive measures on stroke occurrence. It also recognizes the enhancements of our capabilities .o define anatomic lesions in the brain and in the blood vessels in living patients by technological developments. The outline summarizes the classification of the clinical and pathologic disorders and the background material on prevention, clinical assessment, evaluation , status of the patient following stroke, and anatomy. The anatomy and pathology are sufficiently defined in the outline; therefore, the descriptive material, which follows the outline precisely, does not provide information for anatomy and pathology. The document begins with the classification and then provides an orderly format for proceeding from prevention through clinical assessment and evaluation to the poststroke status of the patient and to the organization of the anatomical terms. It is intended …