Cerebral Vascular Imaging Research Articles

Sturge-weber syndrome and cerebral vascular av malformation in an african-american adolescent.

The purpose of this study was to report the case of a 16-year-old black man who without ocular history or physician-recognized dermatologic signs was found to have Sturge-Weber syndrome. Color flow Doppler ultrasound and cerebral vascular imaging showed a child with Sturge-Weber syndrome with a cerebral vascular AV malformation. Color flow Doppler ultrasound and cerebral vascular imaging showed a total retinal detachment, diffuse choroidal hemangioma, and cerebral vascular AV malformation consistent with the diagnosis of Sturge-Weber syndrome. This case shows that this child with typical ocular vascular findings of Sturge-Weber syndrome and a cerebral AV malformation did not show recognizable evidence of a port wine stain during several physician examinations because of the child's darkly pigmented skin color.

Focal parenchymal lesions in community-acquired bacterial meningitis in adults: a clinico-radiological study

Here, we analyzed the frequency, morphological pattern, and imaging characteristics of focal lesions as a consequence of community-acquired bacterial meningitis. We hypothesized that diffusion-weighted imaging combined with contrast-enhanced imaging, serial scanning, and multimodal vascular studies would provide further insight into the pathological basis of such parenchymal lesions in bacterial meningitis. We reviewed clinical and imaging data (i.e., magnetic resonance tomography, magnetic resonance angiography, computed tomography angiography, digital subtraction angiography) of 68 adult patients admitted to our neurological intensive care unit between March 1998 and February 2009 with the diagnosis of community-acquired bacterial meningitis. We identified seven patients with parenchymal lesions. These lesions could be attributed to four morphological patterns: (1) territorial cerebral ischemia, (2) perforating vessels ischemia, (3) ischemia of presumed cardiac origin, and (4) isolated cortical lesions. Whereas the patterns (1) and (2) were associated with vasculopathy of large- and medium-sized vessels (as shown by cerebral vascular imaging), vessel imaging in (3) and (4) did not show abnormal findings. Our study implies that parenchymal lesions in acute bacterial meningitis are mainly ischemic and due to involvement of large-, medium-, and small-sized arteries of the brain. Diffusion-weighted imaging combined with conventional, CT-, or MR-based cerebral angiography revealed the underlying pathophysiological mechanisms in the majority of patients. Furthermore, we detected two patients with isolated bilateral cortical involvement and normal vessel imaging. These lesions might represent ischemia due to the involvement of small pial and intracortical arteries.

Cerebral Vascular Imaging: Methods, Applications, and Considerations

Cerebral Vascular Imaging: Methods, Applications, and Considerations

最新の脳卒中画像診断 脳のＭＲ ａｎｇｉｏｇｒａｐｈｙとｖａｓｃｕｌａｒ ｉｍａｇｉｎｇの進歩

最新の脳卒中画像診断 脳のＭＲ ａｎｇｉｏｇｒａｐｈｙとｖａｓｃｕｌａｒ ｉｍａｇｉｎｇの進歩

Transcranial color-coded sonography of the basal cerebral circulation. Reference data from 115 volunteers.

Transcranial color-coded sonography is a new development in noninvasive cerebral vascular imaging. Reference data using this technique are described. Blood velocities and pulsatility and resistance indices were determined in the anterior cerebral, middle cerebral, posterior cerebral, vertebral, and basilar arteries in 115 volunteers after correction for the angle of insonation. Of 1265 basal arterial segments, 1053 were insonated (83%). The vertebral (98%), basilar (92%), middle cerebral (84%), and posterior (P1) cerebral arteries (84%) were the most successfully insonated, with the anterior (73%) and posterior (P2) cerebral arteries (72%) the least successfully insonated. Mean and end-diastolic blood velocities decreased significantly with age in all vessels (middle cerebral artery mean velocity: 20 to 39 years, 74 cm/s [71-76]; > 60 years, 58 cm/s [55-61], P < .0001; mean with 95% confidence intervals), and peak systolic velocity decreased significantly except in the posterior (P2) cerebral artery. Blood velocities were higher in women except in the > 60-year group. Velocities showed the least interhemispheric asymmetry in the middle cerebral artery (r = .85 and r = .83, peak and mean velocities, respectively) and the greatest asymmetry in the posterior (P2) cerebral artery (r = .58 and r = .59, peak and mean velocities, respectively). Pulsatility and resistance indices increased significantly with age in all vessels (middle cerebral artery pulsatility index: 20 to 39 years, 0.84 [0.82-0.87], > 60 years, 0.97 [0.93-1.02], P < .0001; middle cerebral artery resistance index: 20 to 39 years, 0.55 [0.54-0.56], > 60 years, 0.62 [0.60-0.64], P < .0001). Transcranial color-coded sonography can image the basal cerebral arteries and distinguish vertebral from basilar artery flow and enables pulsed Doppler interrogation with correction for the angle of insonation.

Intracranial aneurysms and arteriovenous malformations: Transcranial colour-coded sonography as a diagnostic aid

Transcranial colour-coded sonography (TCCS) is a new development in noninvasive cerebral vascular imaging. We studied 5 patients with known intracranial aneurysms and 12 patients with arteriove-nous malformations (AVM). We were unable to image any of the aneurysms (all 5 mm or less in diameter) using colour flow ultrasound. Similarly, pulsed wave Doppler interrogation failed to reveal any flow disturbances. Nine out of 12 AVMs were successfully visualised as serpiginous structures and the principal feeder vessels were identified in 11 cases. Blood flow velocities in the feeder vessels were elevated compared with the same vessel contalaterally (median [cm/s]; peak systolic 227 vs. 89, P = 0.001; mean 178 vs. 57, P = 0.001; end diastolic 138 vs. 37, P < 0.0005). Pulsatility indices (PI) and resistance indices (RI) in the feeder vessels were reduced relative to the same vessel contralaterally (median PI 0.46 vs. 0.94, P < 0.0005; median RI 0.37 vs. 0.59, P < 0.0005). At present, TCCS appears of little value in the diagnosis of intracranial aneurysms, but it shows promise for the imaging of AVMs and their haemodynamic study.

Combined use of duplex imaging and magnetic resonance angiography for evaluation of patients with symptomatic ipsilateral high-grade carotid stenosis

Purpose: Advances in cerebral vascular imaging suggest that patients with critical levels of carotid artery stenosis (>70%) who have symptoms can be identified accurately and necessary information about the intracranial and extracranial circulation obtained before surgery without conventional angiography. We have used carotid duplex imaging in combination with magnetic resonance angiography (MRA) to evaluate 20 patients with symptomatic ipsilateral high-grade carotid stenosis.Methods: All patients underwent CT and magnetic resonance imaging brain scans, as well as MRA and conventional arteriography of the cerebral circulation. Magnetic resonance angiograms were obtained with two-dimensional phase contrast and time-of-flight techniques. Phase contrast was used for intracranial vascular imaging and for determining qualitative flow velocities and the direction of blood flow in the circle of Willis. Two-dimensional time of flight was used to assess the carotid bifurcations.Results: Twenty patients with symptoms (six with strokes, 11 with transient ischemic attacks, and three with amaurosis fugax) had duplex evidence of high-grade carotid stenoses. Computed tomographic and magnetic resonance brain scans were positive for cerebral infarction in six patients with clinical strokes. Comparison of MRA with conventional angiography was 91% accurate for high-grade stenoses and occlusions (sensitivity 100% and specificity 90% for stenosis; sensitivity/specificity was 100% for complete occlusion). Comparison of duplex imaging with conventional angiography demonstrated 86% accuracy for detection of severe stenosis or occlusion (sensitivity 94% and specificity 89% for stenosis; sensitivity and specificity were 100% for complete occlusion).Conclusions: This study suggests that combined use of MRA and duplex imaging is accurate for detection and evaluation of high-grade carotid stenoses in patients with symptoms.

Ocular lens dose in cerebral vascular imaging.

Ocular lens dose was considered with respect to cerebral vascular imaging, using both digital subtraction angiography (DSA) and conventional angiography. A dose measurement study is described in which doses were found to be minimal (0.327 cGy) in DSA, but high (60 cGy) using conventional techniques. The use of an undercouch tube in DSA and an increased focus-lens distance, when compared with the conventional angiographic approach were considered the major factors contributing to the difference in lens dose. The implications for selection of technique are discussed.