Background and Purpose: Ischemic episodes distal to an internal carotid artery occlusion are common. We undertook this study to look for evidence of transhemispheric passage of embolic material in this patient category as a mechanism for embolic events. Methods: Seven symptomatic patients with unilateral internal carotid artery occlusion and contralateral stenosis were examined by transcranial ...

BACKGROUND AND PURPOSE A favorable risk-benefit ratio for warfarin compared with aspirin has been reported for the prevention of major vascular events in symptomatic >/=50% intracranial stenoses. Transcranial color-coded duplex sonography (TCCS) criteria providing an accurate detection of >/=50% and <50% stenoses of the anterior, middle, and posterior cerebral arteries and basilar and vertebral...

OBJECTIVE The aim of this study is to investigate the distribution of cerebral artery stenosis in patients with the ischemic cerebrovascular disease. PATIENTS AND METHODS One hundred and forty-four patients with ischemic cerebrovascular disease were enrolled and divided into three age brackets, the youth group (18-44 years old, 12 cases), middle-aged group (45-59 years old, 45 cases), and the...

We report an attempt to obtain images of the basal cerebral arteries and to measure the quantitative flow velocity in these arteries from outside the skull via the color Doppler imaging method. In 25 healthy volunteers, 22-41 years old, the transducer was positioned just superior to the zygomatic arch and anterior to the external ear canal. The absolute flow velocity was calculated by dividing ...

BACKGROUND AND PURPOSE Deficiency of the free fraction of protein S has been associated with arterial or venous stroke. The pathogenesis of vascular occlusion in patients with protein S deficiency is not known. We present two cases of cerebral infarction and deficiency of protein S in which the subjects had progressive intracranial occlusions. CASE DESCRIPTION A 16-year-old girl was admitted ...

BACKGROUND AND PURPOSE We tested the hypothesis that inhibition of nitric oxide synthase activity in brain before ischemia alters cerebral blood flow and decreases brain injury after 4 hours of middle cerebral artery occlusion in cats. METHODS Halothane-anesthetized cats underwent 4 hours of left middle cerebral artery occlusion after they were randomly assigned to receive either intravenous ...

medications. Neurological examination revealed decerebrate rigidity and bilateral Babinski signs. CT on one day after admission demonstrated broad low-density area in the bilateral cerebral hemispheres, including the area of bilateral anterior cerebral artery and middle cerebral artery, but sparing the brainstem and occipital lobe (figure 1). Bilateral internal carotid artery embolisation was i...

BACKGROUND Caffeine is present in a variety of beverages and food and is widely consumed. In a previous study of patients recovering from an acute ischaemic stroke using transcranial Doppler ultrasound we demonstrated a fall in middle cerebral artery blood velocity of 12% following ingestion of 250 mg caffeine. The aim of this study was to investigate if this velocity change reflected a change ...

BACKGROUND AND PURPOSE Acute decreases in the MR T2*-weighted signal have been reported in experimental models of middle cerebral artery occlusion. This has been attributed to blood deoxygenation in association with an increased brain oxygen extraction fraction. The aim of this study was to detect this signal by susceptibility-weighted MR imaging in acute ischemic stroke patients. METHODS Dyn...

PURPOSE To correlate the location of large subcortical infarcts with the site of cerebrovascular occlusive disease. METHODS We examined CT and angiographic findings of 38 patients with major arterial occlusive disease and newly developed large subcortical infarcts of 2.0 cm or more, which were classified into three types: striatocapsular infarcts in the basal ganglia, terminal supply area inf...