Each intracranial aneurysm in this study had at least one spiral flow. The WSS was lower and OSI was higher at the apex of the spiral flow than the whole aneurysmal wall.
Purpose:To visualize the hemodynamics of the intracranial arteries using time-resolved three-dimensional phasecontrast (PC)-MRI (4D-Flow).
Materials and Methods:MR examinations were performed with a 1.5T MR unit on six healthy volunteers (22-50 years old, average ϭ 30 years). 4D-Flow was based on a radiofrequency (RF)-spoiled gradient-echo sequence, and velocity encoding (VENC) was performed along all three spatial directions. Measurements were retrospectively gated to the electrocardiogram (ECG), and cine series of three-dimensional (3D) data sets were generated. The voxel size was 1 ϫ 1 ϫ 1 mm, and acquisition time was 30 -40 minutes. 4D data sets were calculated into time-resolved images of 3D streamlines, 3D particle traces, and 2D velocity vector fields by means of flow visualization software.
Results:We were able to see the 3D streamlines from the circle of Willis to the bilateral M2 segment of the middle cerebral arteries (MCAs). Time-resolved images of 3D particle traces also clearly demonstrated intracranial arterial flow dynamics. 2D velocity vector fields on the planes traversing the carotid siphon or the basilar tip were clearly visualized. These results were obtained in all six volunteers.
Conclusion:4D-Flow helped to elucidate the in vivo 3D hemodynamics of human intracranial arteries. This method may be a useful noninvasive means of analyzing the hemodynamics of intracranial arteries in vivo.
BACKGROUND AND PURPOSE:The stiffness of intracranial tumors affects the outcome of tumor removal. We evaluated the stiffness of 4 common intracranial tumors by using MR elastography and tested whether MR elastography had the potential to discriminate firm tumors preoperatively.
With the elastic belt, miscalculation of the pancreatic stiffness was reduced. MRE showed differences of stiffness between normal pancreas and pancreatic lesions.
A 31-year-old man presented with a ruptured right extracranial vertebral artery aneurysm associated with neurofibromatosis type 1, manifesting as acute onset of right neck and shoulder pain, and right supraclavicular mass. Three-dimensional computed tomography angiography showed a large aneurysm involving the right extracranial vertebral artery associated with a pseudoaneurysm. The aneurysm was successfully treated by transarterial endovascular trapping with detachable coils. Extracranial vertebral artery aneurysm is rare, but the mortality of ruptured cases is extremely high, so early diagnosis and early treatment are important. The present case shows that endovascular treatment was very effective.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.