[Duplex sonography of the vertebral arteries. 2. Clinical application].

The purpose of this report is to demonstrate pathological findings such as hypoplasia, stenosis and occlusion that were diagnosed by duplex-ultrasonography of vertebral arteries. Duplex scanning provides complementary to the continuous wave Doppler examination more accurate haemodynamical and morphological information for the diagnosis of hypoplasia or intracranial stenosis. In comparison with DSA this method may give additional information allowing to differentiate between vertebral aplasia and occlusion at the origin.