Doppler Cerebrovascular Examination: Improved Results with Refinements in Technique

SUMMARY Doppler ultrasonic assessment of extracranial carotid occlusive disease has been modified to decrease the incidence of false positive and negative diagnoses. The technique, which assessed directional flow in the frontal artery and the influence of se-quential compression of each temporal, infraorbital, facial and com-mon carotid artery, was performed on 152 vessels visualized by con-trast arteriography. Presence or absence of significant (> 50%) stenosis or occlusion of the internal carotid artery was identified cor-rectly in 150 vessels (98.7%). Inasmuch as the classic temporal artery compression test only detected 39 of the 61 abnormal Doppler studies (64%), the more complete examination is recommended for screen-ing patients for significant carotid artery obstruction. DOPPLER ULTRASONIC assessment of supraorbital artery flow response to temporal artery compression, as described by Brockenbrough,1 has been useful to detect non-invasively obstruction of the extracranial internal carotid artery. Normally, flow in the supraorbital artery, a branch of the ophthalmic artery, is directed out of the orbit and is augmented by temporal artery compression. In the presence of significant stenosis or occlusion of the internal carotid artery, flow in the supraorbital artery may be reversed and may diminish or be obliterated by temporal artery compres-sion. Most investigators only employ the temporal artery com-pression maneuver when performing a Doppler cerebro-vascular examination2"6 and a significant number (5-27%) of false positive and negative diagnoses have been reported. Many other sources of collateral circulation, both extra-cranial and intracranial, may exist in obstruction of the in-ternal carotid artery and are detectable only by additional compression maneuvers.6 In this paper, we describe the tech-nique and the improved results of a more complete Doppler cerebrovascular examination