BACKGROUND MR techniques have been very powerful in providing indicators of tissue perfusion, particularly in studies of cerebral ischemia. There is considerable interest in performing absolute perfusion measurements, with the aim of improving the characterization of tissue "at risk" of stroke. However, some important caveats relating to absolute measurements need to be taken into account. The ...

The purpose of this study was to evaluate variability in the quantification of myocardial perfusion images obtained by a group of experienced operators using two widely used programs. The Cedars Emory quantitative analysis program (CEqual) was used to quantify the size of perfusion defects and the Cedars-Sinai quantitative gated single-photon emission tomography program was used to quantify lef...

Background The quest to quantify myocardial perfusion has been largely motivated by the desire to obtain quantitative, observer-independent, and reproducible measures of myocardial perfusion. Spiral pulse sequences have multiple advantages for myocardial perfusion imaging including high acquisition efficiency, high signal to noise (SNR) and robustness to motion. We have developed a spiral pulse...

Background The feasibility and pre-clinical validation of pixel-wise quantification of myocardial perfusion on standard and high-resolution first-pass perfusion CMR images has been recently described. However, the diagnostic criteria for the detection of CAD have not yet been defined and normal values in healthy subject are unknown. Aim of this study was to define normal reference values of str...

Background Cardiac perfusion MRI enables quantification of myocardial blood flow in ml/min/g. However, signal intensity (SI) saturation of the arterial input function (AIF) leads to underestimation of the AIF and errors in perfusion quantification. Dual bolus experiments avoid this by using an unsaturated dilute bolus to measure the AIF and have been shown to be accurate against gold standard m...

Information on renal perfusion is essential for the diagnosis and prognosis of kidney function. Quantification using gadolinium chelates is limited as a result of filtration through renal glomeruli and safety concerns in patients with kidney dysfunction. Arterial spin labeling MRI is a noninvasive technique for perfusion quantification that has been applied to humans and animals. However, becau...

BACKGROUND The clinical management of patients with coronary artery disease (CAD) often involves a complex assessment of the extent and severity of changes in left ventricular (LV) myocardial perfusion, function and viability. We aimed to explore the feasibility of integrative quantitative representation of LV perfusion, function and viability in adjacent polar plots. In order to assess the cli...

Functional hyperemia, or the increase in focal perfusion elicited by neuronal activation, is one of the primary functions of the neurovascular unit and a hallmark of healthy brain functioning. While much is known about the hemodynamics on the millimeter to tenths of millimeter-scale accessible by MRI, there is a paucity of quantitative data on the micrometer-scale changes in perfusion in respon...