The importance of Doppler studies in asymptomatic intracranial and extracranial arterial disease

Abstract

Knowledge of intracranial and carotid disease in the symptomatic and especially the asymptomatic high risk population may be useful for evaluating future treatment modalities. A group of 204 symptomatic patients and 105 asymptomatic elderly patients at high risk for stroke were tested by carotid duplex ultrasound and transcranial doppler for the presence of carotid and intracranial stenosis. Quantitative measurements of the stenosis were made directly from the hard copy of the carotid duplex and the transcranial doppler. Of the 204 symptomatic patients 168 (83%) had some degree of stenosis: 84 of the 204 (41%) in the intracranial circulation only, 59 (29%) in the internal carotid only, and 26 (13%) in both sets of vessels. Of the asymptomatic patients 85 (81%) had some degree of stenosis; 31 of 105 (30%) in the intracranial circulation only, 35 (33%) in the internal carotid only, and 19 (18%) in both sets of vessels. Statistical analysis did not reveal significant differences between the two groups. The large percentage of intracranial disease in the symptomatic as well as the asymptomatic population at high risk for stroke require further confirmation by good duplex studies of the intracranial circulation. This is important in order to create coherent treatment protocols.