RT Journal Article SR Electronic T1 The diagnosis of internal carotid artery occlusion by directional Doppler sonography of the ophthalmic artery JF Neurology JO Neurology FD Lippincott Williams & Wilkins SP 816 OP 816 DO 10.1212/WNL.22.8.816 VO 22 IS 8 A1 H. R. Müller YR 1972 UL http://n.neurology.org/content/22/8/816.abstract AB