Non-linear attenuation of the Arterial Input Function (AIF) is a major problem in first-pass MR perfusion imaging due to the high concentration of the contrast agent in the blood pool. This paper presents a technique to reconstruct the true AIF using signal intensities in the myocardium and the attenuated AIF based on a Hierarchical Bayesian Model (HBM). With the proposed method, both the AIF a...

The proximity of immune cell aggregations to the vasculature is a hallmark of multiple sclerosis. Furthermore, it is widely accepted that inflammation is able to modulate the microcirculation. Until recently, the detection of cerebral blood perfusion changes was technically challenging, and perfusion studies in multiple sclerosis patients yielded contradictory results. However, new developments...

Quantification of perfusion in white matter is still difficult due to its low level, causing an often insufficiently low signal-to-noise ratio, and its long and inhomogeneous transit delays. Here, a technique is presented that accurately measures white matter perfusion by combining a spectroscopic single-voxel localization technique (point-resolved spectroscopy) with a pulsed arterial spin labe...

BACKGROUND AND PURPOSE Cerebral blood flow (CBF) abnormalities are previously demonstrated in white matter disease. A gradation of change may exist between patients with mild and more severe white matter disease. An association between blood brain barrier dysfunction, increasing age and white matter disease is also suggested. The purpose of this study was to quantify and correlate white matter ...

BACKGROUND No noninvasive technique is currently capable of "real-time" assessment and monitoring of cerebral blood flow (CBF). We hypothesized that cerebral perfusion could be accurately measured and monitored in "real time" with contrast-enhanced ultrasound (CEU). METHODS AND RESULTS Cerebral perfusion was assessed in 9 dogs through a craniotomy with CEU at baseline and during hypercapnia a...

BACKGROUND Current myocardial perfusion measurements make use of an ECG-gated pulse sequence to track the uptake and washout of a gadolinium-based contrast agent. The use of a gated acquisition is a problem in situations with a poor ECG signal. Recently, an ungated perfusion acquisition was proposed but it is not known how accurately quantitative perfusion estimates can be made from such datase...

Positron emission tomography (PET) was applied to the measurement of myocardial perfusion using the perfusion tracer 13N-labeled ammonia. 13N ammonia was delivered intravenously to 13 healthy volunteers both at rest and during supine bicycle exercise. Dynamic PET imaging was obtained in three cross-sectional planes for 10 minutes commencing with each injection. The left ventricle was divided in...

Methods 75 datasets including 37 patients (25 after revasculated infarctions, 12 after radiation therapy in the treatment of Hodgkin’s disease) and 38 healthy volunteers were evaluated. 18 examinations were performed under adenosine induced stress. Perfusion series were acquired in a 1.5T scanner (Siemens) using an ECG-gated saturation recovery true-FISP sequence with the following parameters: ...

Myocardial blood flow (MBF) quantification with PET is generally considered a gold standard for the measurement of myocardial perfusion in absolute terms. The resulting values of MBF and myocardial flow reserve (MFR) used to determine the diagnostic path of a patient have a twofold (for MFR) or threefold (for MBF) range in literature, which interferes with establishing meaningful cutoffs̶numeric...