نتایج جستجو برای: planar imaging
تعداد نتایج: 511276 فیلتر نتایج به سال:
background the ability to follow the distribution and migration of biologically active cells in human is essential for the development of cell-based therapies and diagnostics. nuclear medicine imaging is widely applied in clinic as an attractive technique for in vivo wbc and stem cell tracking. the aim of this study was to evaluate prosthesis infection of a 51 years old man with previous histor...
PURPOSE Ultrafast sequences based on "Hybrid" spatiotemporal encoding (SPEN) replace echo-planar imaging's phase encoding "blips," while retaining a k-space readout acquisition. Hardware imperfections during acquisition may lead to ghosts and striped artifacts along the SPEN dimension; akin to echo-planar imaging's Nyquist ghosts, but weaker. A referenceless method to eliminate these artifacts ...
Quantitative diffusion tensor imaging (DTI) offers a valuable tool to probe the microstructural changes in neural tissues in vivo, where absolute quantitation accuracy and reproducibility are essential. It has been long recognized that measurement of apparent diffusion coefficient (ADC) using DTI could be influenced by the presence of water molecules in cerebrovasculature. However, little is kn...
fMRI has unique potential in the study of psychiatric patients, particularly in characterizing individual variations and changes over time. We have performed four studies of patients with schizophrenia, using three different fMRI acquisition protocols: (1) 3-D echo-shifted FLASH, a multishot volumetric approach; (2) 3-D PRESTO, a hybid of multishot and echo-planar imaging (EPI) methods that als...
A robust modification of echo-planar imaging dubbed double-shot echo-planar imaging with center-out trajectories and intrinsic navigation (DEPICTING) is proposed, which permits imaging at ultra-short echo time. The k-space data is sampled by two center-out trajectories with a minimal delay achieving a temporal efficiency similar to conventional single-shot echo-planar imaging. Intersegment phas...
Introduction 2D phase contrast (PC) CMR is currently the standard clinical imaging sequence for evaluation of blood flow [1]. Recently, 3D time-resolved PC CMR (4D-PC) has been used for quantification and visualization of blood flow in all three directions of a volume [2]. However, such acquisitions require long scan times (often 10-20 minutes), which reduces its clinical feasibility and leads ...
BACKGROUND A velocity-selective binomial excitation scheme for myocardial first-pass perfusion measurements with hyperpolarized 13C substrates, which preserves bolus magnetization inside the blood pool, is presented. The proposed method is evaluated against gadolinium-enhanced 1H measurements in-vivo. METHODS The proposed excitation with an echo-planar imaging readout was implemented on a cli...
The aim of this study was to apply sensitivity-encoding (SENSE) echo-planar imaging (EPI) to diffusion tensor MR imaging of the cervical cord, an anatomic region where MR imaging is particularly challenging. This technique was implemented with a SENSE reduction factor of 2 and used for imaging a water phantom and five healthy volunteers. Off-resonance artifacts were notably reduced compared wit...
In magnetic resonance electrical impedance tomography (MREIT), currents are injected into an object, the resulting magnetic flux density is measured using MRI, and the conductivity distribution reconstructed using these MRI data. The relatively long acquisition times of conventional MREIT methods limit the signal averaging rate and are susceptible to motion artifacts. In this study, we reconstr...
Parallel imaging methods become increasingly available on clinical MR scanners. To investigate the potential of sensitivity-encoded single-shot EPI (SENSE-EPI) for functional MRI, five imaging protocols at different SENSE reduction factors (R) and matrix sizes were compared with respect to their noise characteristics and their sensitivity toward functional activation in a motor task examination...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید