Introduction Brain oxygenation level is physiological information of interest in numerous cerebral pathologies. However, few MRI techniques for quantifying oxygen-level parameters (such as partial pressure of oxygen, oxygen extraction fraction...) are available. Recently, He and Yablonskiy proposed an in vivo MR approach – quantitative BOLD – to obtain local blood oxygen saturation (lSO2) maps ...

Introduction Anterior cruciate ligament (ACL) tear is a common knee injury, and is a risk factor of post-traumatic osteoarthritis (OA) [1]. The disease is frequently associated with bone marrow edema-like (BMEL) lesions which exhibit as an area of high signal intensity in T2-weighted, fat-saturated fast spin echo MR images. BMEL is also commonly seen in OA and has been associated with disease p...

In recent years there has been interest in intramolecular dipolar interactions in macromolecules (MM) in tissues, such as brain, spinal cord, and rat-tail using NMR and MRI (1-4).It was suggested that these interactions could be probed by three successive steps: 1) exciting selectively the MM magnetization, 2) transferring the MM magnetization to the water, and 3) obtaining images based on the ...

1 I n t r o d u c t i o n Safety measures like airbags and safety belts are nowadays commonly applied to improve the crash worthiness of road vehicles. Many governments stimulate or oblige by law car producers to include these devices in the vehicle design. Maximum values are imposed on parameters that quantitatively describe the severity of injuries. Examples are the Head Injury Criterion (HIC...

Modern Standard Arabic (MSA) uses five different particles to express sentential negation: the invariant particle maa, the particle laa and its tensed counterparts lam (PAST) and lan (FUT), and laysa which is marked only for SUBJ agreement. Partial analyses of these elements are offered in other frameworks, notably Minimalism (Shlonsky, 1997; Benmamoun, 2000), but have not to date received an a...

Introduction Low frequency fluctuations (LFFs) in the resting state (RS) BOLD signal have been utilized to map functional connectivity in the rat brain [1]. The BOLD signal contains contributions from cerebral blood flow (CBF), cerebral blood volume (CBV), and the local rate of oxygen consumption (CMRO2). RS data collected with CBV weighting results in a significant shift of the low frequency p...

Introduction Quantitative mapping of brain oxygenation levels using MR would be of considerable interest for numerous pathologies. Recently, He and Yablonskiy proposed an in vivo MR approach – quantitative BOLD – to obtain blood volume fraction (BVf) and local blood oxygen saturation level (lSO2) maps [1] [2]. To analyze the difference observed between T2 and T2* (i.e.T2’), they distinguished t...

Introduction: The BOLD (Blood oxygenation level dependent) signal is inherently ambiguous, reflecting a combination of metabolic and vascular responses. Changes in oxidative metabolism can be estimated from the BOLD signal using calibration methods described previously [1,2]. These calibration procedures typically involve estimating a parameter M, which is equivalent to the maximum possible BOL...

M. Lustig, J. H. Lee, D. L. Donoho, J. M. Pauly Electrical Engineering, Stanford University, Stanford, CA, United States, Statistics, Stanford University, Stanford, CA, United States Introduction We propose a fast imaging method based on undersampled k-space spiral sampling and non-linear reconstruction. Our approach is inspired by theoretical results in sparse signal recovery [1,2] showing tha...

Introduction Several multiple quantum coherence (MQC) filters have been proposed for the detection of compounds with J-coupled spin systems [1]. One of these compounds is lactate, which is used as a biomarker of anaerobic glucose metabolism, therefore applicable to many clinical areas, like oncology. The resonance of lactate is obscured by lipid signals or macro molecules having the same chemic...