Recanalization of intracranial carotid occlusion detected by duplex carotid sonography.

Abstract

We studied three patients with internal carotid artery occlusion at the siphon who had recanaiization during 1 month of close observation. Angiography and duplex carotid sonography (DCS) were repeated serially in each patient. Blood flow patterns detected by DCS were classified into three patterns by specific angiographic changes. The distal occiusive flow pattern on DCS corresponds to internal carotid artery occlusion at the siphon angiographically, the median flow pattern on DCS corresponds to partial recanaiization, and a normal flow pattern on DCS indicates almost complete recanaiization. Since DCS can be easily repeated, the exact time of recanaiization can be determined noninvasively. In all three patients, hemorrhagic infarction observed on computed tomograms occurred at the time of recanaiization detected by DCS. DCS demonstrates that recanaiization is one of the mechanisms of hemorrhagic infarction. (Stroke 1989;20:680-686)

Benign outcome of objectively proven spontaneous recanalization of internal carotid artery occlusion

“…On the other hand, once occlusion is established, the subsequent risk of cerebrovascular events seems to be lower (2% to 5% per year), even in initially symptomatic patients. [5][6][7][8]11,12 Color-coded Doppler ultrasound (CCDU) imaging is the first-line noninvasive method for the diagnosis of carotid artery disease, 13,14 featuring a high sensitivity (95%), specificity (100%), and accuracy (97%), even in differentiating a true occlusion from a near-occlusion. 15,16 Traditionally, despite a general complication rate as high as 5% and a stroke risk of 1.0%, the accepted reference test to confirm the presence of ICA stenosis or occlusion was selective contrast angiography.…”

Spontaneous Recanalization of Occluded Standard Extracranial-Intracranial Arterial Bypass

“…Thirdly, dissection can result in reversible vessel occlusion, and with cardioembolism dissection in the carotid artery represents the most common cause of spontaneous reversible occlusion [12,16,17,18]. The latter cannot be excluded, but there were no indices to assume an accumulation of cardioembolism in our study.…”

Carotid Duplex Ultrasonography Can Predict Outcome of Intravenous Alteplase Therapy for Hyperacute Stroke

“…As an alternative, carotid US can detect intracranial ICA occlusion based on the absence of enddiastolic flow velocity. 16 The accuracy of the diagnosis of carotid occlusion by US is sufficiently high compared with MRA findings. B-mode, color Doppler, and pulsedwave Doppler carotid US can identify an ICA occlusion in about 5 minutes.…”

“…On US, absent color flow signals on the ICA indicates the occlusion at or proximal to the artery, and absent end-diastolic flow velocity of the ICA indicates intracranial ICA occlusion. 16 Thus, carotid artery occlusion was defined as either of these US findings (Fig 1). Based on the US findings, the patients were divided into 2 groups: those with carotid artery occlusion (designated the CO group) and those without carotid artery occlusion (designated the non-CO group).…”