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Middle Cerebral Artery Territories (middle + cerebral_artery_territory)
Selected AbstractsContralateral EEG Slowing and Amobarbital Distribution in Wada Test: An Intracarotid SPECT StudyEPILEPSIA, Issue 2 2000Seung Bong Hong Summary: Purpose: To relate the occurrence of contralateral electroencephalogram slowing (CES) to amobarbital distribution, we performed electroencephalogram (EEG) monitoring and intracarotid single photon emission computed tomography (SPECT) during an intracarotid amobarbital procedure (IAP). Methods: IAP was performed on 22 patients with temporal lobe epilepsy. CES was defined as the occurrence of significant EEG slowing on the contralateral hemisphere (>50% of the ipsilateral hemisphere slowing) after amobarbital injection. To map the distribution of the amobarbital, we injected a mixture of amobarbital and 99m technetium-ethylcysteinate dimer (99m Tc-ECD) into the internal carotid artery and performed a brain SPECT 2 h later. In the SPECT images, regions of interest were determined by ipsilateral and contralateral anterior cerebral artery territories (iACA, cACA), ipsilateral and contralateral middle cerebral artery territories (iMCA, cMCA), and ipsilateral and contralateral posterior cerebral artery territories (iPCA, cPCA), as well as ipsilateral and contralateral anterior and posterior mesial temporal regions (iAMT, cAMT, iPMT, cPMT). The perfusion of amobarbital was interpreted visually in each region. Results: Amobarbital was distributed in the iMCA in all the patients; in the iACA in 20 (90.9%) patients; in the iAMT in 14 (63.5%); and in the iPCA and iPMT in only two (9.1%). CES was observed in 13 (59.1%) patients. Cross-perfusion of amobarbital in limited areas of the cACA were observed in only four of 13 patients. Wada retention memory scores (WRMS) showed no significant difference between the CES- (n = 9) and CES+ (n = 13) groups. Conclusions: Amobarbital rarely perfused the iPCA territory and the iPMT region and was rarely delivered to the contralat-eral hemisphere. The occurrence of CES was not related to the cross-perfusion of amobarbital. CES appears to be produced by a transient functional disconnection from the ipsilateral hemisphere. [source] Bilateral Internal Carotid Artery Dissection Mimicking Inflammatory Demyelinating DiseaseJOURNAL OF NEUROIMAGING, Issue 4 2003C. Lie MD ABSTRACT Background and Purpose. Internal carotid artery (ICA) dissection (ICAD) may be extremely difficult to diagnose only on the basis of historical information and clinical signs, and even standard brain imaging (computed tomography [CT], T2-weighted magnetic resonance imaging [MRI]) may not be sufficient to delineate the underlying pathology clearly, as shown in this case. Methods. The clinical presentation and parenchymal lesion pattern on CT were suggestive of inflammatory demyelinating disease, and additional multiparametric MRI was per-formed. Results. Diffusion-weighted MRI, magnetic resonance angiography, and perfusion-weighted MRI revealed acute ischemic lesions, bilateral ICA obstruction, and bilateral hypoperfusion in the middle cerebral artery territories. Bilateral ICAD was confirmed by Doppler and duplex ultrasound, and anticoagulation therapy was initiated. A follow-up examination showed recanalization of the obstructed ICAs and the normalization of cerebral perfusion. Conclusion. This case illustrates the importance of demonstrating the pathology and the value of multiparametric MRI techniques for the diagnosis and monitoring of ICAD and its hemodynamic consequences. [source] Presumed perinatal ischemic stroke: Vascular classification predicts outcomesANNALS OF NEUROLOGY, Issue 4 2008Adam Kirton MD, FRCPC Objective Perinatal stroke commonly causes childhood neurological morbidity. Presumed perinatal ischemic stroke (PPIS) defines children presenting outside a normal perinatal period with chronic, focal infarction on neuroimaging. Infarcts are assumed to represent arterial strokes, but recent evidence suggests the periventricular venous infarction (PVI) of infants born preterm may also occur in utero and present as PPIS. Using the largest published cohort, we aimed to define arterial and PVI PPIS syndromes and their outcomes. Methods A PPIS consecutive cohort was identified (SickKids Children's Stroke Program, 1992,2006). Systematic neuroradiological scoring executed by blinded investigators included previously defined arterial stroke syndromes. PVI criteria included unilateral injury with at least four of the following conditions: (1) focal periventricular encephalomalacia, (2) internal capsule T2 prolongation, (3) cortical and (4) relative basal ganglia sparing, and (5) remote hemorrhage. Arterial and PVI classifications were validated and correlated with neurological outcomes (Pediatric Stroke Outcome Measure). Results In 59 PPISs (64% male), 94% of lesions fell within potential middle cerebral artery territories. Although arterial proximal M1 infarction was most common (n = 19; 35%), venous PVI was second (n = 12; 22%) and accounted for 75% of subcortical injuries. Motor outcomes (mean follow-up, 5.3 years) were predicted by basal ganglia involvement including leg hemiparesis, spasticity, and need for assistive devices (p < 0.01). Nonmotor outcomes were associated with cortical involvement, including cognitive/behavioral outcomes, visual deficits, and epilepsy (p < 0.01). Classification interrater reliability was excellent (correlation coefficients > 0.975). Interpretation Recognizable PPIS patterns predict long-term morbidity and may guide surveillance, therapy, and counseling. PVI is an underrecognized cause of PPIS and congenital hemiplegia. Ann Neurol 2008 [source] Reactivity of Brain Parenchymal Arterioles after Ischemia and ReperfusionMICROCIRCULATION, Issue 6 2008MARILYN J. CIPOLLA ABSTRACT Objective: We investigated the effect of ischemia and reperfusion on the vasoactive function of penetrating brain parenchymal arterioles under pressurized conditions. Methods: Parenchymal arterioles (<50 ,m in diameter) from within the middle cerebral artery territory were dissected from male Wistar rats that were either nonischemic control (n = 16) or ischemic for one hour and reperfused for 24 hours (n = 16) by temporary filament occlusion of the middle cerebral artery. Arterioles were mounted on glass cannulas within an arteriograph chamber that allowed for the measurement of lumen diameter and control over intravascular pressure. Results: After one hour of equilibration at 10 mmHg, spontaneous myogenic tone developed in both groups of animals, constricting control arterioles from 69 ± 9 to 49 ± 11 ,m (29.5 ± 10.2%) and ischemic arterioles from 66 ± 9 to 45 ± 11 ,m (33.1 ± 14.1%); p > 0.05. Contraction to the nitric oxide synthase inhibitor nitro-L-arginine (10,4M) was significantly diminished in ischemic arterioles, constricting only 3.2 ± 3.3 vs. 15.6 ± 12.5% in control arterioles (p = 0.017). Both groups dilated to nifedipine; however, the response was significantly diminished after ischemia. The EC50 for nifedipine in control arterioles was 3.54 ± 0.11 vs. 9.90 ± 0.71 nM for ischemic arterioles (p = 0.024). Conclusions: These findings demonstrate that functional changes occur in brain parenchymal arterioles after ischemia and reperfusion, a result that may significantly influence stroke outcome by altering blood flow to an ischemic region. [source] Multi-variate analysis predicts clinical outcome 30 days after middle cerebral artery infarctionACTA NEUROLOGICA SCANDINAVICA, Issue 1 2000M. Giroud Background and purpose, To evaluate the functional prognostic value of proton magnetic resonance spectroscopy performed within the 5 days of an infarction of the middle cerebral artery territory, compared with previously demonstrated prognostic factors. Methods, Proton magnetic resonance spectroscopy was performed on 77 consecutive non-comatosed patients during the acute stage of middle cerebral artery infarction. The functional status was determined for each patient via the Orgogozo score. Proton magnetic resonance spectroscopic data were acquired in the infarction and in contra-lateral normal tissue and the results were expressed as metabolite ratios. Correlations were evaluated between the Orgogozo score at day 1 and day 30, the age, the sex, the volume of the infarction, and the metabolic ratios. Results, In a monovariate analysis, the decrease of the NAA/choline ratio was correlated with a low Orgogozo score at days 1 and 30 (P<0.05) and with a large infarction (P<0.05). A stepwise analysis showed a significant relationship between the Orgogozo score at day 30 and the Orgogozo score at day 1, the sex, the volume of infarction, and the NAA/Cho ratio within the infarction. Conclusions, Our work demonstrates that a good clinical outcome at day 30 depends on a good initial clinical score at day 1, a small volume of infarction, a small decrease of NAA/Cho, and being of the female gender. [source] | ||||||||||