[Cerebrovascular Doppler studies--a potent tool in neuroangiology]

Cerebrovascular disease is caused in about half of the patients by obstructions in the extracranial cerebral arteries. In the other half, stroke is due in roughly equal proportions to obstructive intracranial arterial lesions, emboli from the heart, or intracranial hemorrhage. Half of the patients with major ischemic stroke had previous warning signs in the form of transient ischemic attacks (TIA), reversible ischemic neurologic deficit (RIND) or infarction with only minor residual deficit not limiting daily activity, professional skills, and quality of life. Investigation of patients with warning signs of impending ischemic stroke is mandatory in order to prevent other events with possible major disability, but also, in patients with acute infarction, in order to choose the appropriate early therapy and rehabilitation. Routine cerebrovascular Doppler examination based on continuous-wave equipment has been successfully used to detect extracranial arterial obstructions. In the authors' experience of more than 12000 patients this noninvasive diagnostic tool makes it possible-in conjunction with the patient's history and the results of the clinical examination-to differentiate between obstructions needing surgery and lesions small enough to warrant medical treatment. Minor lesions which do not disturb blood flow locally, or accessible to available continuous-wave Doppler equipment, can be detected with real-time ultrasound imaging systems, i.e. B-mode or B-mode-Doppler-(duplex) systems in addition to routine Doppler examination. These complex systems also serve to follow-up patients with minor lesions which are not treated, or treated medically, in regard to deterioration, possible invariability, or even regression of a lesion.