Abstract：
:SSFP-based fMRI techniques, known for their high specificity and low geometrical distortion, look promising for high-resolution brain mapping. Nevertheless, they suffer from lack of speed and sensitivity, leading them to be exploited mostly in high-field scanners. Radial acquisition can help with these inefficiencies through better tSNR and more effective coverage of the spatial frequencies. Here, we present a SSFP-fMRI approach and experimentally investigate it at 3 T scanners using radial readout for acquisition. In particular, the visual activity is mapped through three bSSFP techniques: 1- Cartesian, 2- Radial with re-gridding reconstruction, 3- Radial with Polar Fourier Transform (PFT) reconstruction. In the PFT technique streaking artifacts, generated at high acceleration rates by re-gridding reconstruction, are avoided and pixel size in the final framework is retrospectively selectable. General agreement, but better tSNR of Radial reading, was first confirmed for these techniques in detection of neural activities at 2 × 2 mm2 in-plane resolution for all 28 subjects,. Next the outcome of the PFT algorithm with 1 × 1 mm2 pixel size was compared to images reconstructed by re-gridding (from the same raw data) with the identical pixel size through interpolation. The localization of the activity showed improvement in PFT over interpolation both qualitatively (i.e., well-fitting in gray-matter) and quantitatively (i.e., higher z-scores and tSNR). The proposed technique can therefore be considered as a remedy for lack of speed and sensitivity in SSFP-based fMRI, in conventional field strengths. The proposed approach is particularly useful in task-based studies when we concentrate on a ROI considerably smaller than FOV, without sacrificing spatial resolution.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Malekian V,Rastegar F,Shafieizargar B,Nasiraei-Moghaddam Adoi
10.1016/j.mri.2020.09.005subject
Has Abstractpub_date
2020-12-01 00:00:00pages
171-180eissn
0730-725Xissn
1873-5894pii
S0730-725X(20)30359-3journal_volume
74pub_type
杂志文章abstract：:We compared the ability and reproducibility of a fast fluid-attenuated inversion recovery (fast-FLAIR) sequence with and without a magnetization transfer (MT) pulse for detecting and measuring multiple sclerosis (MS)-related abnormalities on magnetic resonance imaging (MRI) scans from 20 patients. The Contrast-to-Nois...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(98)00182-9
更新日期：1999-04-01 00:00:00
abstract：:We assessed the magnetic resonance (MR) imaging characteristics of two categories of epileptogenic substrates, neoplasms, and vascular malformations, to determine MR sensitivity and typical imaging features. A blinded retrospective analysis was performed on MR scans from 41 patients who had a neoplasm or vascular malf...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(95)02026-p
更新日期：1995-01-01 00:00:00
abstract：:Despite intense research on the blood oxygenation level-dependent (BOLD) signal underlying functional magnetic resonance imaging, our understanding of its physiological basis is far from complete. In this study, it was investigated whether the so-called poststimulus BOLD signal undershoot is solely a passive vascular ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2009.04.003
更新日期：2009-10-01 00:00:00
abstract：PURPOSE:To evaluate the clinical outcomes of conservative management by observation with MRI of patients with branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs). MATERIALS AND METHODS:Twenty-three consecutive patients, who were followed up by MRI with magnetic resonance cholangiopancreatography (MRCP) ove...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2010.06.026
更新日期：2010-12-01 00:00:00
abstract：:Trabecular bone structure and bone density contribute to the strength of bone and are important in the study of osteoporosis. Wavelets are a powerful tool in characterizing and quantifying texture in an image. The purpose of this study was to validate wavelets as a tool in computing trabecular bone thickness directly ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2006.09.020
更新日期：2007-04-01 00:00:00
abstract：:Hippocampal metabolite concentrations were determined by localized in vivo proton magnetic resonance spectroscopy (1H MRS) in eleven patients suffering from refractory mesial temporal lobe epilepsy (MTLE), as well as in eleven age-matched healthy volunteers, and compared with patient history, postoperative outcome and...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(98)00123-4
更新日期：1998-10-01 00:00:00
abstract：:The purpose of this study was to assess the benefits of a 3 T scanner and an eight-channel phased-array head coil for acquiring three-dimensional PRESS (Point REsolved Spectral Selection) proton (H-1) magnetic resonance spectroscopic imaging (MRSI) data from the brains of volunteers and patients with brain tumors rela...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2006.07.012
更新日期：2006-12-01 00:00:00
abstract：:A new magnetic resonance imaging technique was applied to the Taylor-Couette and spiral Poiseuille (Taylor-Couette with superposed mean axial flux) flows for the first time. The experimental technique is a combination of spatial tagging methods and a snapshot FLASH imaging sequence, which allows the full-field visuali...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(99)00121-6
更新日期：2000-02-01 00:00:00
abstract：:More than a dozen Nuclear Magnetic Resonance (NMR) imaging methods have been described using different radio-frequency pulse sequences, magnetic field gradient variations, and data processing. In order to have a theoretical understanding in the most general case, we have conceived a computer program for the simulation...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(84)90065-1
更新日期：1984-01-01 00:00:00
abstract：:Measurements have been carried out in six subjects at magnetic fields of 1.5, 3 and 7 T, with the aim of characterizing the variation of T2* with field strength in human brain. Accurate measurement of T2* in the presence of macroscopic magnetic field inhomogeneity is problematic due to signal decay resulting from thro...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2007.02.014
更新日期：2007-07-01 00:00:00
abstract：PURPOSE:To present preliminary, in vivo temperature measurements during MRI of a pig implanted with a deep brain stimulation (DBS) system. MATERIALS AND METHODS:DBS system (Medtronic Inc., Minneapolis, MN) was implanted in the brain of an anesthetized pig. 3.0-T MRI was performed with a T/R head coil using the low-SAR...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2012.11.005
更新日期：2013-06-01 00:00:00
abstract：:Laplace inversion has been widely used in analyzing nuclear magnetic resonance data to obtain a spectrum of decay time constant, such as the T(2) spectrum. However, due to the ill-conditioned nature of such inversion, it is difficult to determine the reliability and error of the resulting spectrum. This article descri...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章,评审
doi：10.1016/j.mri.2006.11.023
更新日期：2007-05-01 00:00:00
abstract：PURPOSE:To evaluate the utility of fat fraction (FF) for the differentiation of different breast tissues and in various breast tumor subtypes using in vivo proton (1H) magnetic resonance spectroscopy (MRS). METHODS:1H MRS was performed on 68 malignant, 35 benign, and 30 healthy volunteers at 1.5 T. Malignant breast ti...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2018.02.004
更新日期：2018-06-01 00:00:00
abstract：:Gadolinium-based magnetic resonance (MR) contrast agents (GBCM) causes a devastating systemic fibrosing illness, nephrogenic systemic fibrosis (NSF), in patients with reduced kidney function. GBCM targets iron-recycling CD163- and ferroportin-expressing macrophages to release labile iron that mediates gadolinium toxic...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章,评审
doi：10.1016/j.mri.2016.08.016
更新日期：2016-12-01 00:00:00
abstract：:Functional MR imaging of the alert, behaving monkey is being used more and more often to detect activation patterns and guide electrophysiological research investigating the neural basis of behavior. Several labs have reported fMRI data from the awake monkey, but none of them has studied and systematically corrected t...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2007.03.002
更新日期：2007-07-01 00:00:00
abstract：:The advantages of the application of NMR imaging to the studies of enhanced oil recovery methods that include polymer slug flooding, combination slug flooding, and thermal soaking are described. ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(96)00192-0
更新日期：1996-01-01 00:00:00
abstract：OBJECTIVES:The objectives of this study were to develop protocols that measure abdominal fat and calf muscle lipids with magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS), respectively, at 3 T and to examine the correlation between these parameters and insulin sensitivity. MATERIALS AND METHOD...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2007.06.006
更新日期：2008-02-01 00:00:00
abstract：:In independent component analysis (ICA), principal component analysis (PCA) is generally used to reduce the raw data to a few principal components (PCs) through eigenvector decomposition (EVD) on the data covariance matrix. Although this works for spatial ICA (sICA) on moderately sized fMRI data, it is intractable for...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2005.12.013
更新日期：2006-06-01 00:00:00
abstract：:Image artifacts due to 14 gauge radiotherapy electromagnetic (EM) transponders were assessed on conventional spin echo images, and corrected using metal artifact reduction techniques: high bandwidth, view angle tilting (VAT), and slice encoding for metal artifact correction (SEMAC). Large areas of signal loss and/or p...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2019.02.005
更新日期：2019-06-01 00:00:00
abstract：:With the conventional 3D MR angiographic sequences, it is difficult to prescribe multiple phases in different orientations, though multiple phases may be prescribed in the same orientation as the initial scan. Magnetic resonance angiography (MRA) was performed in which three slabs were prescribed in different orientat...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(99)00003-x
更新日期：1999-07-01 00:00:00
abstract：:A single-sided mobile NMR apparatus with a small Halbach magnet was constructed for the first time. It is lightweight, compact and exhibits good sensitivity. The weight of the device is only 2 kg, and the NMR signal of the pencil eraser block can be detected in one shot using the device. This study describes the chara...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2006.04.005
更新日期：2006-10-01 00:00:00
abstract：:The effect of slice orientation on reproducibility and sensitivity of 3T fMRI activation using a motor task has been investigated in six normal volunteers. Four slice orientations were used; axial, oblique axial, coronal and sagittal. We applied analysis of variance (ANOVA) to suprathreshold voxel statistics to quanti...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(01)00399-x
更新日期：2001-12-01 00:00:00
abstract：:Recent compressed sensing techniques allow signal acquisition with less sampling than required by the Nyquist-Shannon theorem which reduces the data acquisition time in magnetic resonance imaging (MRI). However, prior knowledge becomes essential to reconstruct detailed features when the sampling rate is exceedingly lo...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2015.10.009
更新日期：2016-02-01 00:00:00
abstract：PURPOSE:This study aimed to establish the topographical and zonal T2 patterns of multi-resolution MRI in medial tibial cartilage in a canine model of osteoarthritis (OA), initiated by the anterior cruciate ligament (ACL) transection surgery, and studied after 8-weeks and 12-weeks post-surgery. METHODS:Articular cartil...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2021.01.002
更新日期：2021-01-22 00:00:00
abstract：:The role of susceptibility effects in the production of artifacts in chemical shift images generated by the selective excitation technique is discussed. The effects are demonstrated in images of phantom samples of agarose gels containing small air bubbles. The artifacts can lead to erroneous interpretations, in which ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(92)90022-r
更新日期：1992-01-01 00:00:00
abstract：:The adiabatic Shinnar-Le Roux (SLR) algorithm for radiofrequency (RF) pulse design enables systematic control of pulse parameters such as bandwidth, RF energy distribution and duration. Some applications, such as diffusion-weighted imaging (DWI) at high magnetic fields, would benefit from RF pulses that can provide gr...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2014.04.003
更新日期：2014-09-01 00:00:00
abstract：:Various analogs of NMR and MRI are now technically possible in optics; specifically, high-resolution laser-pulse shaping and complex pulse sequence generation with well-defined phase shifts has been demonstrated. Here we summarize this technology and discuss the potential for these methods to enhance optical functiona...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2003.08.024
更新日期：2003-12-01 00:00:00
abstract：:We present the case of a 44-year-old man who complained of cervical pain. He was treated with physiotherapy and analgetics. Because of persistent pain, computed tomography (CT) scan and MRI were performed. They revealed an osteolytic destruction of the fourth cervical vertebra. The patient was treated surgically for r...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章,评审
doi：10.1016/j.mri.2004.01.006
更新日期：2004-05-01 00:00:00
abstract：:The hippocampal formation is a brain system that is implicated in learning and memory. The major input to the hippocampus arrives from the entorhinal cortex (EC) to the dentate gyrus (DG) through the perforant path. In the present work, we have investigated the functional properties of this connection by concomitantly...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2008.02.018
更新日期：2008-09-01 00:00:00
abstract：:There is increasing interest in imaging short T2 species which show little or no signal with conventional magnetic resonance (MR) pulse sequences. In this paper, we describe the use of three-dimensional ultrashort echo time (3D UTE) sequences with TEs down to 8 μs for imaging of these species. Image contrast was gener...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2010.11.003
更新日期：2011-05-01 00:00:00
