Although pathology of the innominate artery (IA) is not frequent, it causes relevant impairment of extracranial circulation and sometimes cerebrovascular events. Definite differentiation of high-grade stenosis from occlusion of the IA has not been obtained until now with continuous-wave (C.W.) Doppler and duplex system ultrasound, and thus the direct evaluation of IA is not reliable by noninvasive methods. In this study the authors suggest an indirect method of evaluation of IA pathology based on the study of carotid, subclavian, and vertebral arteries (VA) with echo-Doppler-color-flow (EDCF) (with linear--phase array probes of 7.5 and 5 MHz). In the last two years they studied 6 patients with IA pathology (2 with occlusion (occ), 1 with stenosis of 80% and 3 with subocclusive stenosis > 90%). In both patients with occ, right VA flow was inverted, and also the right common carotid (CC) was involved (occ in 1 case and inverted flow in the other); in the 3 subocclusive stenoses a lowered systolic flow in the CC was recorded (48 vs 85 cm/sec, 41 vs 77, and 23 vs 109). In the 80% stenosis, besides the inverted flow in VA, only a reduced diastolic flow in CC was also recorded (19 vs 33 cm/sec measured in the left side). All patients with high grade stenosis were successfully confirmed by an angiographic study, including the different degree of stenosis. Five of the 6 patients underwent surgical correction with a restored flow in the previously involved artery. Only 1 patient with occlusion is waiting for surgical correction.(ABSTRACT TRUNCATED AT 250 WORDS)