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Assessment of vascular properties is essential to diagnosis and follow-up and basic understanding of pathogenesis in brain tumors. In this study, a procedure is presented that allows concurrent estimation of cerebral perfusion, blood volume, and blood-brain permeability from dynamic T(1)-weighted imaging of a bolus of a paramagnetic contrast agent passing(More)
To investigate if perfusion measured with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can be used to differentiate radiation necrosis from tumor recurrence in patients with high-grade glioma. The study was approved by the institutional review board and informed consent was obtained from all subjects. 19 patients were recruited following(More)
UNLABELLED We present an approach for head MR-based attenuation correction (AC) based on the Statistical Parametric Mapping 8 (SPM8) software, which combines segmentation- and atlas-based features to provide a robust technique to generate attenuation maps (μ maps) from MR data in integrated PET/MR scanners. METHODS Coregistered anatomic MR and CT images(More)
Exploratory (i.e., voxelwise) spatial methods are commonly used in neuroimaging to identify areas that show an effect when a region-of-interest (ROI) analysis cannot be performed because no strong a priori anatomical hypothesis exists. However, noise at a single voxel is much higher than noise in a ROI making noise management critical to successful(More)
OBJECTIVE It has been suggested that migraine is caused by neural dysfunction without involvement of vasodilatation. Because dismissal of vascular mechanisms seemed premature, we examined diameter of extra- and intracranial vessels in migraine without aura patients. METHODS A novel high-resolution direct magnetic resonance angiography imaging technique(More)
PURPOSE To investigate the within and between subject variability of quantitative cerebral blood flow (CBF) measurements in normal subjects using various MRI techniques and positron emission tomography (PET). MATERIALS AND METHODS Repeated CBF measurements were performed in 17 healthy, young subjects using three different MRI techniques: arterial spin(More)
The reconstruction of PET brain data in a PET/MR hybrid scanner is challenging in the absence of transmission sources, where MR images are used for MR-based attenuation correction (MR-AC). The main challenge of MR-AC is to separate bone and air, as neither have a signal in traditional MR images, and to assign the correct linear attenuation coefficient to(More)
AIM To explore a possible relationship between vasodilatation and delayed headache we examined the effect of pituitary adenylate cyclase-activating polypeptide-38 (PACAP38) on the middle meningeal artery (MMA) and middle cerebral artery (MCA) using high resolution magnetic resonance angiography (MRA). METHODS In a double-blind, randomized,(More)
Both [18F]-fluoroethyltyrosine (FET) PET and blood volume (BV) MRI supplement routine T1-weighted contrast-enhanced MRI in gliomas, but whether the two modalities provide identical or complementary information is unresolved. The aims of the study were to investigate the feasibility of simultaneous structural MRI, BV MRI and FET PET of gliomas using an(More)
Magnetic resonance imaging (MRI) has proven useful in evaluating oxygenation in several types of tissue and blood. This study evaluates brain tissue oxygenation changes between normoxia and hyperoxia in healthy subjects using dynamic T1 and T2*-weighted imaging sequences. The change in FiO2 induced by hyperoxia caused a significant decrease in T1. A model(More)