Cerebrovascular Doppler examination and cerebral angiography--alternative or complementary?

Obstructions in the extracranial cerebral arteries can be detected noninvasively by directional Doppler ultrasound technique using 'indirect' and 'direct' criteria. The indirect criteria are based on measurement of flow in the common carotid and in the terminal branches of the ophthalmic artery before and after the common carotid artery and branches of the external carotid artery are compressed. With the direct criteria, internal and external carotid artery are differentiated by diastolic flow, and local inhomogenetics of flow (turbulence) are detected. Flow in the vertebral artery is picked up transorally in the oropharynx. The Doppler examination was used in 2230 patients of whom 436 underwent angiography. The results of Doppler and angiography correlated in more than 90% of the cases.