Background and Purpose-We sought to evaluate the diagnostic value of echo-enhanced transcranial color-coded duplex sonography (TCCD) and the clinical relevance of vascular pathology assessed by sonography for early clinical outcome in acute ischemic stroke. Methods-We present 23 consecutive patients with an anterior circulation stroke in whom clinical examination, CT, and ultrasonography were performed within 5 hours after the onset of symptoms. Transcranial Doppler sonography (TCD) and unenhanced and contrast-enhanced TCCD (Levovist, 4 g, 300 mg/mL) were compared for their ability to detect middle cerebral artery (MCA) occlusion and flow velocity reduction suggesting hemodynamic impairment in the MCA distribution pathway. Sonographic examination times were registered. Baseline clinical characteristics and CT findings were assessed. Neurological deficit was quantified according to the National Institutes of Health Stroke Scale score, with an early clinical improvement defined as decrease of the score by 4 or more points or a complete resolution of the deficit on day 4. Results-Contrast-enhanced TCCD enabled diagnosis of intracranial vascular pathology in 20 affected hemispheres, whereas unenhanced TCCD and TCD were conclusive in 7 and 14 hemispheres, respectively (Pϭ0.0001). Contrastenhanced TCCD was superior in evaluating distal carotid (carotid-T) occlusion and differentiating major vessel occlusions from patent arteries with flow velocity diminution. Mean examination time for enhanced TCCD ranged from 5 to 7 minutes, depending on the number of investigated vessels (without or with MCA branches). Logistic regression selected a patent MCA without reduced blood flow velocity as the only independent predictor for an early clinical improvement (PϽ0.01). Conclusions-Contrast-enhanced TCCD is a promising tool for early prognosis in anterior circulation stroke. It is considered superior to unenhanced TCCD and TCD. (Stroke. 1998;29:955-962.)

Background and Purpose-The present study investigated the influence of the antiplatelet agent acetylsalicylic acid (ASA) on cerebral microembolism as detected by transcranial Doppler sonography (TCD). Methods-Nine patients with recent transient ischemic attack or minor stroke of arterial origin were investigated. Eight had not received an antiplatelet or anticoagulant medication before TCD, and in 1 patient a preexisting ASA medication (100 mg/d) had not been changed since the onset of stroke symptoms. An initial 1-hour TCD monitoring was extended for an additional 2.5 hours after an intravenous bolus injection of 500 mg ASA and was repeated for 1 hour on the following day.

Cerebrovascular reserve capacity evaluated by preoperative transcranial Doppler carbon dioxide testing is a major determinant of stroke risk in patients with carotid artery stenosis/occlusion undergoing cardiac surgery with cardiopulmonary bypass. Its assessment facilitates identification of patients with an excess perioperative stroke risk.

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