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Anterior Cerebral Artery (anterior + cerebral_artery)
Selected AbstractsHemodynamic Effects of Innominate Artery Occlusive Disease on Anterior Cerebral ArteryJOURNAL OF NEUROIMAGING, Issue 1 2002Teng-Yeow Tan MD Stenoses of the innominate artery (IA) may affect flow conditions in the carotid arteries. However, alternating flow in ipsilateral anterior cerebral artery (ACA) due to IA stenosis is extremely rare. A 49-year-old woman who was evaluated for symptomatic cerebrovascular disease presented with right latent subclavian and right carotid system steal. Transcranial Doppler examination displayed systolic deceleration wave-forms in the right terminal internal carotid artery and alternating flow in the right ACA. Magnetic resonance angiography demonstrated tight stenosis of the right IA. For a thorough study of the hemodynamic effects of IA stenosis, a combination of duplex and transcranial Doppler examination is required. [source] Time course of cerebral hemodynamics in cryptococcal meningitis in HIV-negative adultsEUROPEAN JOURNAL OF NEUROLOGY, Issue 7 2007W.-N. Chang To evaluate the cerebral hemodynamics in cryptococcal meningitis (CM) patients using non-invasive studies. Serial trans-cranial color-coded sonography (TCCS) and magnetic resonance angiography (MRA) studies were performed to measure the cerebral vasculopathy of 12 HIV-negative CM patients. With TCCS, 8 of the 22 middle cerebral arteries (MCAs) showed stenotic velocities, whereas the time-mean velocity (Vmean) of the 20 anterior cerebral arteries (ACAs), 22 posterior cerebral arteries (PCAs), and 12 basilar arteries (BAs) did not. In total, five patients had stenotic velocities, three of whom had bilateral M1 stenosis (<50%), whilst two had unilateral M1 stenosis (<50%). The Vmean of MCA increased from day 1 to day 35 and substantially decreased thereafter. The mean Pulsatility Index (PI) in the studied vessels was higher during the study period. A mismatch of the findings between TCCS and MRA studies were also demonstrated. There was a high incidence and a longer time-period of disturbed cerebral hemodynamics during the clinical course of CM. However, because of the limited case numbers for this study, further large-scale studies are needed to delineate the clinical characteristics and therapeutic influence of cerebrovascular insults in HIV-negative CM patients. [source] Acute isolated cerebral mucormycosis in a patient with high grade non-Hodgkins lymphomaEUROPEAN JOURNAL OF NEUROLOGY, Issue 4 2000M. Zarei A 57-year-old female in complete remission of grade IV non-Hodgkin lymphoma whilst on intensive chemotherapy, suddenly developed unilateral hemispheric stroke with a fatal outcome in 3 days. She was apyrexial and had received antifungal prophylaxis during her treatment. Post-mortem examination showed complete thrombosis of the internal carotid artery leading to infarction in the territory of the middle and anterior cerebral arteries. Microscopic examination of the brain showed involvement of intra-cranial vessel walls and brain parenchyma by mucormyces, with no evidence of systemic mucormycosis. Isolated cerebral mucormycosis is a rare occurrence, more commonly found in intravenous drug abusers, but can occur in patients with haematological malignancy. [source] Changes in blood flow velocity in the middle and anterior cerebral arteries evoked by walkingJOURNAL OF CLINICAL ULTRASOUND, Issue 3 2002Krassen Nedeltchev MD Abstract Purpose Transcranial Doppler sonography (TCD) is an established method for assessing changes in blood flow velocity (BFV) coupled to brain activity. Our objective was to investigate whether walking induces measurable changes in BFV in healthy subjects. Methods Changes in BFV in both middle cerebral arteries (MCAs) of 40 healthy adult subjects during walking on a treadmill were measured using bilateral TCD. In 8 of the 40 subjects, 1 anterior cerebral artery (ACA) was monitored simultaneously with the contralateral MCA. The percentage increase in BFV (BFVI%) compared with the baseline velocity (V0), the percentage decrease in BFV (BFVD%) compared with the V0, and the normalized ACA-MCA ratio were analyzed. Results The overall mean (± standard deviation [SD]) V0 was 59.9 ± 11.6 cm/second in the left MCA and 60.1 ± 12.9 cm/second in the right MCA. Women had higher V0 values than men had. Walking evoked an initial mean overall BFVI% in both left (8.4 ± 5.1%) and right MCAs (9.1 ± 5.1%), followed by a decrease to below baseline values in 38 of 40 subjects. A statistically significant increase of the normalized ACA-MCA ratio was measured, indicating that changes in BFV in the ACA territory were coupled to brain activation during walking. Conclusions The use of functional TCD showed different changes in BFV in the ACAs and MCAs during walking. This method may be an interesting tool for monitoring progress in patients with motor deficits of the legs, such as paresis. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30:132,138, 2002; DOI 10.1002/jcu.10047 [source] Patent ductus arteriosus and cystic periventricular leucomalacia in preterm infantsACTA PAEDIATRICA, Issue 3 2001P Pladys Aim: To test the association between early disturbances in hemodynamics induced by left-to-right shunting through the duct and cystic periventricular leucomalacia. Patients: Forty-six preterm infants (27,32 wk) admitted to the neonatal intensive care unit with risk criteria. Methods: Patent ductus arteriosus was evaluated on days 1 and 4, and was significant (sPDA) in cases of absent or reversed end diastolic flow in the subductal aorta. Resistance index was measured in the anterior cerebral artery and in the subductal aorta. Main outcome: Diagnosis of cystic periventricular leucomalacia between day 10 and day 50. Results: The 12 infants who developed cystic periventricular leucomalacia were compared with those who did not. On day 1, sPDA was more frequent (64% vs 26%; p= 0.03) in the cystic periventricular leucomalacia group, left ventricular output was higher (median = 341 vs 279mlkg -1.min -1; p= 0.005), and rescue surfactant was more frequently used (83% vs 47%; p= 0.03). This latter association was confirmed by multivariate analysis. Resistance index in the anterior cerebral artery was increased in cases of significant patent ductus arteriosus (p < 0.01) and was correlated with resistance index in the subductal aorta. Conclusion: On day 1 in this selected population, sPDA has an effect on blood flow velocity waveform in cerebral arteries and is associated with an increase in the emergence of cystic periventricular leucomalacia. This association could be casual rather than causal. [source] Accuracy of transcranial Doppler sonography for predicting cerebral infarction in aneurysmal subarachnoid hemorrhageJOURNAL OF CLINICAL ULTRASOUND, Issue 8 2006Ji-Yong Lee MD Abstract Purpose. To evaluate the accuracy of transcranial Doppler (TCD) sonography using different criteria for predicting cerebral infarction due to symptomatic vasospasm. Methods. We retrospectively evaluated the clinical and radiologic data of consecutive patients admitted with acute aneurysmal subarachnoid hemorrhage (SAH) in the anterior cerebral circulation between January 2001 and June 2002. TCD sonographic examinations were performed on alternate days up to 20 days after admission. Cerebral infarction was defined on CT as a new hypodensity in the vascular distribution with corresponding clinical symptoms. Vasospasm was diagnosed as mild or severe when TCD sonography revealed a mean blood flow velocity (MBFV) greater than 120 and 180 cm/s in the middle or anterior cerebral artery and in the intracranial part of the internal carotid artery, respectively. Results. A total of 93 patients with aneurysmal SAH in the anterior cerebral circulation were included. Vasospasm was demonstrated by TCD sonography in 60 patients (64.5%) and was shown via multivariable logistic regression analysis to be predictive of cerebral infarction (OR 3.11, 95% CI 1.46,6.59), with an 82.6% and 69.6% sensitivity, a 41.4% and 77.1% specificity, a 31.7% and 50.0% positive predictive value, and an 87.9% and 88.5% negative predictive value when the MBFV was greater than 120 and 180 cm/s, respectively. Conclusions. Vasospasm on TCD was found to be predictive of symptomatic cerebral infarction on CT, but its positive predictive value remained low despite the adoption of restrictive TCD criteria for vasospasm. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:380,384, 2006 [source] Changes in blood flow velocity in the middle and anterior cerebral arteries evoked by walkingJOURNAL OF CLINICAL ULTRASOUND, Issue 3 2002Krassen Nedeltchev MD Abstract Purpose Transcranial Doppler sonography (TCD) is an established method for assessing changes in blood flow velocity (BFV) coupled to brain activity. Our objective was to investigate whether walking induces measurable changes in BFV in healthy subjects. Methods Changes in BFV in both middle cerebral arteries (MCAs) of 40 healthy adult subjects during walking on a treadmill were measured using bilateral TCD. In 8 of the 40 subjects, 1 anterior cerebral artery (ACA) was monitored simultaneously with the contralateral MCA. The percentage increase in BFV (BFVI%) compared with the baseline velocity (V0), the percentage decrease in BFV (BFVD%) compared with the V0, and the normalized ACA-MCA ratio were analyzed. Results The overall mean (± standard deviation [SD]) V0 was 59.9 ± 11.6 cm/second in the left MCA and 60.1 ± 12.9 cm/second in the right MCA. Women had higher V0 values than men had. Walking evoked an initial mean overall BFVI% in both left (8.4 ± 5.1%) and right MCAs (9.1 ± 5.1%), followed by a decrease to below baseline values in 38 of 40 subjects. A statistically significant increase of the normalized ACA-MCA ratio was measured, indicating that changes in BFV in the ACA territory were coupled to brain activation during walking. Conclusions The use of functional TCD showed different changes in BFV in the ACAs and MCAs during walking. This method may be an interesting tool for monitoring progress in patients with motor deficits of the legs, such as paresis. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30:132,138, 2002; DOI 10.1002/jcu.10047 [source] Importance of Jugular Valve Incompetence in Contrast Transcranial Doppler Ultrasonography for the Diagnosis of Patent Foramen OvaleJOURNAL OF NEUROIMAGING, Issue 3 2003M. Akif Topçuoglu MD ABSTRACT Transcranial Doppler (TCD) ultrasound with the intravenous injection of agitated saline as contrast (cTCD) is an effective method for detecting right-to-left intracardiac and extracardiac shunt (RLS); however, the sensitivity of cTCD in the diagnosis of RLS remains slightly less than that of transesophageal echocardiography, even in patients with adequate transtemporal ultrasonic bone windows. The authors present a case with cTCD underestimating RLS because of jugular valve incompetence in a 42-year-old man presenting with an episode of transient aphasia. Three weeks after transcatheter closure of a patent foramen ovale associated with an atrial septal aneurysm, he experienced 2 episodes of amaurosis fugax. Following a negative 45-minute embolus detection study with power M-mode TCD, the patient underwent a cTCD study with monitoring of the left middle cerebral artery (MCA), the anterior cerebral artery, and the submandibular extracranial internal carotid artery. A single microbubble (MB) was detected in the left MCA in only 1 of 5 studies; the remaining runs all failed to detect an RLS. Significant MB reflux was noted in the left internal jugular vein because of jugular valve incompetence. The authors conclude that incompetence of the jugular vein valve can result in a false negative cTCD study for RLS detection. [source] Hemodynamic Effects of Innominate Artery Occlusive Disease on Anterior Cerebral ArteryJOURNAL OF NEUROIMAGING, Issue 1 2002Teng-Yeow Tan MD Stenoses of the innominate artery (IA) may affect flow conditions in the carotid arteries. However, alternating flow in ipsilateral anterior cerebral artery (ACA) due to IA stenosis is extremely rare. A 49-year-old woman who was evaluated for symptomatic cerebrovascular disease presented with right latent subclavian and right carotid system steal. Transcranial Doppler examination displayed systolic deceleration wave-forms in the right terminal internal carotid artery and alternating flow in the right ACA. Magnetic resonance angiography demonstrated tight stenosis of the right IA. For a thorough study of the hemodynamic effects of IA stenosis, a combination of duplex and transcranial Doppler examination is required. [source] Regional cerebral blood flow autoregulation in patients with fulminant hepatic failureLIVER TRANSPLANTATION, Issue 6 2000Fin Stolze Larsen The absence of cerebral blood flow autoregulation in patients with fulminant hepatic failure (FHF) implies that changes in arterial pressure directly influence cerebral perfusion. It is assumed that dilatation of cerebral arterioles is responsible for the impaired autoregulation. Recently, frontal blood flow was reported to be lower compared with other brain regions, indicating greater arteriolar tone and perhaps preserved regional cerebral autoregulation. In patients with severe FHF (6 women, 1 man; median age, 46 years; range, 18 to 55 years), we tested the hypothesis that perfusion in the anterior cerebral artery would be less affected by an increase in mean arterial pressure compared with the brain area supplied by the middle cerebral artery. Relative changes in cerebral perfusion were determined by transcranial Doppler,measured mean flow velocity (Vmean), and resistance was determined by pulsatility index in the anterior and middle cerebral arteries. Cerebral autoregulation was evaluated by concomitant measurements of mean arterial pressure and Vmean in the anterior and middle cerebral arteries during norepinephrine infusion. Baseline Vmean was lower in the brain area supplied by the anterior cerebral artery compared with the middle cerebral artery (median, 47 cm/s; range, 21 to 62 cm/s v 70 cm/s; range 43 to 119 cm/s, respectively; P < .05). Also, vascular resistance determined by pulsatility index was greater in the anterior than middle cerebral artery (median, 1.02; range 1.00 to 1.37 v 0.87; range 0.75 to 1.48; P < .01). When arterial pressure was increased from 84 mm Hg (range 57 to 95 mm Hg) to 115 mm Hg (range, 73 to 130 mm Hg) during norepinephrine infusion, Vmean remained unchanged in 2 patients in the anterior cerebral artery, whereas it increased in the middle cerebral artery in all 7 patients. In the remaining patients, Vmean increased approximately 25% in both the anterior and middle cerebral arteries. Thus, this study could only partially confirm the hypothesis that autoregulation is preserved in the brain regions supplied by the anterior cerebral artery in patients with FHF. Although the findings of this small study need to be further evaluated, one should consider that autoregulation may be impaired not only in the brain region supplied by the middle cerebral artery, but also in the area corresponding to the anterior cerebral artery. [source] Cardiocirculatory effects of patent ductus arteriosus in extremely low-birth-weight infants with respiratory distress syndromePEDIATRICS INTERNATIONAL, Issue 3 2003Senji Shimada Abstract Background:,Cardiocirculatory effects of hemodynamically significant patent ductus arteriosus (hsPDA) have not been systematically studied in extremely low-birth-weight (ELBW) infants with respiratory distress syndrome (RDS). The objective of the present study was to evaluate the effects of hsPDA on the left ventricular output (LVO) and organ blood flows in ELBW infants with RDS. Methods:,Extremely low-birth-weight infants (birth-weight <1000 g) treated with surfactant for RDS were studied by serial Doppler flow examinations. Doppler flow variables in 19 infants in whom hsPDA developed (hsPDA group) were compared with those in 19 infants without hsPDA matched for gestational age, birth-weight, and postnatal age (non-hsPDA group). All infants in the hsPDA group had pharmacologic closure of ductus arteriosus when hsPDA developed. Results:,Before pharmacological closure of PDA, the hsPDA group had significantly higher LVO, lower blood flow volume of the abdominal aorta, and lower mean blood flow velocities in the celiac artery, superior mesenteric artery, and renal artery than the non-hsPDA group. These alterations in the hsPDA group reverted to the levels in the non-hsPDA group after the closure of PDA and had no deleterious effects on the cardiorespiratory status. No significant differences between the groups were found in mean blood flow velocities of the anterior cerebral artery throughout the study period. Conclusion:,These results indicate that although LVO is increased, the splanchnic and renal blood flows are decreased when hsPDA develops in ELBW infants with RDS. The effects of these alterations of LVO and organ blood flows on the cardiorespiratory course seem to be minor when early pharmacologic closure of PDA is done. [source] Central facial palsy revisited: A clinical-radiological study,ANNALS OF NEUROLOGY, Issue 3 2010Luigi Cattaneo MD We investigated the pattern of volitional facial motor deficits in acute stroke patients. We assessed the strength of single facial movements and correlated it to the site of infarct classified on computed tomography scans. Exclusion criteria were previous stroke, cerebral hemorrhage, and subcortical stroke. Results showed that weakness in eyelid closure was associated with anterior cerebral artery (ACA) stroke. Weakness in lip opening was associated with middle cerebral artery (MCA) stroke. We suggest that sparing of upper facial movements in MCA stroke is due to the presence of an upper face motor representation in both the MCA and ACA territories. ANN NEUROL 2010;68:404,408 [source] | ||||||||||||||||||||||