Noninvasive monitoring of internal carotid artery dissection.

BACKGROUND AND PURPOSE Internal carotid artery dissection has increasingly been reported as a cause of transient ischemic attack or stroke. However, scarce data exist on the natural history of the arterial lesions and the temporal profile of recanalization. METHODS We followed 48 patients with 50 angiographically confirmed internal carotid artery dissections by sequential duplex Doppler studies in 2- to 4-day intervals during the first weeks after the onset of symptoms and after 4 weeks in 1- to 2-month intervals for up to 2 years. We assessed sonographic features as well as the frequency and time course of resolution. RESULTS Initial Doppler findings were abnormal in all patients, most of whom (68%) presented with a characteristic bidirectional high-resistance Doppler signal in the internal carotid artery. Gradual recanalization was found in 68% of the dissections after an average interval of 51 days. Changes of Doppler flow patterns in follow-up studies and features of intra-arterial angiography correlated with the development of internal carotid artery dissection and mirrored the recanalization process. CONCLUSIONS Our findings suggest that Doppler sonography provides early recognition of internal carotid artery dissection and monitoring of its resolution. Thus, ultrasound studies may guide clinical decisions according to the development of the dissection.