نتایج جستجو برای: mrsi
تعداد نتایج: 564 فیلتر نتایج به سال:
We propose a Bayesian smoothness prior in the spectral fitting of magnetic resonance spectroscopic images which can be used in addition to commonly employed prior knowledge. By combining a frequency-domain model for the free induction decay with a Gaussian Markov random field prior, a new optimization objective is derived that encourages smooth parameter maps. Using a particular parametrization...
Objective To evaluate quantitatively 3D proton MR spectroscopic imaging (3D H MRSI) data of the prostate in patients with known prostate cancer using anatomical knowledge, compared with a single–voxel–spectra evaluation by blinded experts and automated processing methods. Material and Methods: MRSI data of 10 patients with histologically proven prostate adenocarcinoma, scheduled either for pros...
(1)H MRSI in vivo is increasingly being used to diagnose prostate cancer noninvasively by measurement of the resonance from choline-containing phospholipid metabolites. Although (31) P NMR in vivo or in vitro is potentially an excellent method for probing the phospholipid metabolites prominent in prostate cancer, it has been little used recently. Here, we report an in vitro (31)P NMR comparison...
The finite element method (FEM) is well suited for use in the non-rigid registration of magnetic resonance spectroscopy images (MRSI) with intraoperative ultrasound images of the prostate because FEM provides a principled method for modeling the physical deformation caused when the MRSI intra-rectal imaging probe compresses the prostate. However, FEM requires significant labor and computational...
In this paper, a polynomial fitting improved Bayesian approach is proposed for the reconstruction of volumetric metabolite images from long echo time (TE) whole brain proton magnetic resonance spectroscopic imaging (MRSI) data. The proposed algorithm uses a modified EM (expectation maximization) algorithm that takes into account the partial volume effects contained inside a thick slice MRSI. It...
Conventional Magnetic Resonance Spectroscopic Imaging (MRSI) suffers from both low signal-to-noise (SNR), as well as long acquisition times. The development of high-fidelity gradient coils has opened opportunities for fast k-space encoding schemes that are already used in structural imaging. At the same time, receive-coil arrays using 4 and 23 channels have been developed and reported to produc...
A magnetic resonance spectroscopic imaging (MRSI) pulse sequence based on proton-echo-planar-spectroscopic-imaging (PEPSI) is introduced that measures two-dimensional metabolite maps in a single excitation. Echo-planar spatial-spectral encoding was combined with interleaved phase encoding and parallel imaging using SENSE to reconstruct absorption mode spectra. The symmetrical k-space trajectory...
10B-enriched L-p-boronophenylalanine (BPA) is one of the compounds used in boron neutron capture therapy (BNCT). In this study, several variations of nuclear magnetic resonance spectroscopy (MRS) and spectroscopic imaging (MRSI) were applied to investigate the uptake, clearance and metabolism of the BPA-fructose complex (BPA-F) in normal mouse kidneys, rat oligodendroglioma xenografts, and rat ...
PURPOSE Poorly characterized macromolecular (MM) and baseline artefacts are known to reduce metabolite quantitation accuracy in 1 H MR spectroscopic imaging (MRSI). Increasing echo time (TE) and improvements in MM analysis schemes have both been proposed as strategies to improve metabolite measurement reliability. In this study, the influence of TE and two MM analysis schemes on MRSI reproducib...
3D magnetic resonance spectroscopic imaging (MRSI) has been successfully employed to extract information about brain tumor metabolism, such as cell membrane breakdown, cellular energetics, and neuronal integrity, through its ability to differentiate signals coming from choline (Cho), creatine (Cr), and N-acetyl aspartate (NAA) molecules. The additional presence of lipids within subregions of th...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید