Changes in carotid flow velocity induced by direct percutaneous carotid angiography in man.

Quantitative percutaneous flow velocity measurements are possible in carotid arteries. The results of the direct percutaneous angiography were measured by means of a Doppler directional flow velocity device and registered on a polygraphy. The results indicate an increase in the flow velocity of the injected as well as the non-injected carotid system. This implies that there are no local constrictions of the carotid artery following intervention and, furthermore, it implies a systematic effect of the puncture and injection itself, or of the contrast medium, on the whole cerebral circulation. A diffuse vasodilatation, at least in the cerebral circulation, is postulated. The possible implications are discussed.