Abstract：
:The effects of bone on marrow relaxation in the trabecular volume of the most proximal 3 cm in the left tibia were studied with a RF-spoiled gradient echo MRI protocol on a 1.0 T MR unit. The MR measurements were performed on six healthy volunteers, and repeated within one month in order to assess the precision of the method. In the same subjects, the area bone mineral density (BMD, g/cm2) was measured at the left proximal femur using dual-energy X-ray absorptiometry. The calcaneus of the same side was examined with quantitative ultrasound. The marrow T2* relaxation deviated from a mono-exponential decay, and resembled the decay of subcutaneous fat. The shape of the relaxation curve reflected the presence of several spectral components in bone marrow, and was further influenced by the amount and structure of the surrounding trabecular bone. The bone marrow decays showed substantially reduced inter-subject variability after normalisation of the marrow data fit parameters to corresponding values for s.c. fat. This suggests the use of an internal adipose tissue reference in order to correct for diet-related variations of marrow T2* estimates. The mean relative precision of the MR measurements was between 5% and 10% depending on the data fit model. Moderate-to-strong correlations between DXA BMD indices in the proximal femur and MR parameters were found (r(max)=-0.96; p < 0.01), while ultrasound-derived measures of bone strength measured on the calcaneus demonstrated significantly weaker correlations to the MR parameters (r(max)=-0.78; p > 0.05). The method employed in this study showed reasonable precision and a moderate to good correlation compared to other bone parameters derived at the same extremity, and is a promising tool for the use on patients.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Fransson A,Grampp S,Imhof Hdoi
10.1016/s0730-725x(98)00159-3subject
Has Abstractpub_date
1999-01-01 00:00:00pages
69-82issue
1eissn
0730-725Xissn
1873-5894pii
S0730725X98001593journal_volume
17pub_type
杂志文章abstract：:A four-channel Tic-Tac-Toe (TTT) transmit RF coil was designed and constructed for foot and ankle imaging at 7T MRI. Numerical simulations using an in-house developed FDTD package and experimental analyses using a homogenous phantom show an excellent agreement in terms of B1+ field distribution and s-parameters. Simul...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2017.09.005
更新日期：2018-01-01 00:00:00
abstract：:Pelvic MR (41 patients) and CT (36 patients) examinations were performed on 14 females with a primary pelvic complaint, and on 28 females with a suspicion of local recurrent disease of gynecologic malignant tumor. Benign cystic tumors were found in eight patients, five patients had endometriomas, one had a lymphoma, a...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(93)90409-7
更新日期：1993-01-01 00:00:00
abstract：:Obstructive sleep apnea syndrome (OSAS) is caused by multi-level upper airway obstruction. Anatomic changes at the sites of obstruction may modify the physical or acoustic properties of snores. The surgical success of OSA depends upon precise localization of obstructed levels. We present a case of OSAS who received si...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2015.08.004
更新日期：2015-12-01 00:00:00
abstract：:Tissue water molecules reside in different biophysical compartments. For example, water molecules in the vasculature reside for variable periods of time within arteries, arterioles, capillaries, venuoles and veins, and may be within blood cells or blood plasma. Water molecules outside of the vasculature, in the extrav...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章,评审
doi：10.1016/j.mri.2007.02.006
更新日期：2007-07-01 00:00:00
abstract：PURPOSE:To evaluate non-invasive imaging biomarkers for assessing renal fibrosis. DWI is used to assess renal function; intravoxel incoherent motion (IVIM) provides additional measures of perfusion-related diffusion (D*, blood flow; f, perfusion fraction). We aim to determine if reduced ADC seen in renal fibrosis is at...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2015.07.012
更新日期：2015-12-01 00:00:00
abstract：:The current fMRI study investigated correlations of low-frequency signal changes in the left inferior frontal gyrus, right inferior frontal gyrus and cerebellum in 13 adult dyslexic and 10 normal readers to examine functional networks associated with these regions. The extent of these networks to regions associated wi...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2005.12.006
更新日期：2006-04-01 00:00:00
abstract：:A series of direct shear and nuclear magnetic resonance (NMR) tests were performed on a compacted weakly expansive clay saturated by sodium chloride (NaCl) solutions with different concentrations to study the effect of NaCl solution on the shear strength and its mechanism. Results from the direct shear tests show that...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2019.01.002
更新日期：2019-05-01 00:00:00
abstract：PURPOSE:The detection of small parenchymal hepatic lesions identified by preoperative imaging remains a challenge for traditional pathologic methods in large specimens. We developed a magnetic resonance imaging (MRI) compatible localization device for imaging of surgical specimens aimed to improve identification and lo...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2016.11.021
更新日期：2017-04-01 00:00:00
abstract：:The present study examined initial changes in non-traumatic osteonecrosis of the femoral head (ONF) on T1- and T2-weighted MR images, and fat suppression images. The subjects were 57 renal transplant recipients (37 males and 20 females), whose median age at the time of transplantation was 31.5 years old (range, 10 to ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(01)00424-6
更新日期：2001-09-01 00:00:00
abstract：:Multi-contrast magnetic resonance imaging (MRI) is a useful technique to aid clinical diagnosis. This paper proposes an efficient algorithm to jointly reconstruct multiple T1/T2-weighted images of the same anatomical cross section from partially sampled k-space data. The joint reconstruction problem is formulated as m...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2014.08.025
更新日期：2014-12-01 00:00:00
abstract：:Radio frequency magnetic fields from 5 to 100 kHz off resonance reduce longitudinal magnetization of water in some tissues without affecting the magnetization of simple solutions (Wolff, S.D.; Balaban, R.S. Magnetization transfer contrast (MTC) and tissue water proton relaxation in vivo. Magn. Reson. Med. 10:135-144; ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(90)90050-c
更新日期：1990-01-01 00:00:00
abstract：:We have applied diffusion and relaxation Nuclear Magnetic Resonance experiments to investigate the translational and rotational mobility of adsorbents on quartz and calcite mineral surfaces. On both surfaces it was found that water is the dominant molecule. On the quartz surface the majority of water molecules have a ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2018.10.002
更新日期：2019-02-01 00:00:00
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：:Autofocusing is a postprocessing technique for motion correction, which optimizes an image quality metric against various trial motions. In this work, image metric maps, which are measures of image quality plotted as a function of in-plane 2-D trial translations, are systematically studied to develop improved autofocu...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2006.02.003
更新日期：2006-07-01 00:00:00
abstract：OBJECTIVE:To develop and validate a large field of view phantom and quality assurance software tool for the assessment and characterization of geometric distortion in MRI scanners commissioned for radiation therapy planning. MATERIALS AND METHODS:A purpose built phantom was developed consisting of 357 rods (6mm in dia...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章,评审
doi：10.1016/j.mri.2015.04.003
更新日期：2015-09-01 00:00:00
abstract：BACKGROUND:Blood-oxygen-level-dependent (BOLD) magnetic resonance imaging (MRI) can provide regional measurements of oxygen content using deoxyhemoglobin paramagnetic characteristics. The apparent relaxation rate or R2*(=1/T2*) can be determined from the slope of log (intensity) versus echo time and is directly proport...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2011.10.003
更新日期：2012-04-01 00:00:00
abstract：:The clinical evaluation of three-dimensional time-of-flight MR angiography was prospectively performed in 16 patients with intracranial meningioma. MR angiographic techniques used in this study both with and without gadopentetate dimeglumine made it possible to demonstrate the topographic relationship between the tumo...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(93)90466-q
更新日期：1993-01-01 00:00:00
abstract：PURPOSE:To develop a method for estimating metabolite concentrations using phased-array coils and sensitivity-encoded (SENSE) magnetic resonance spectroscopic images (MRSI) of the human brain. MATERIALS AND METHODS:The method is based on the phantom replacement technique and uses receive coil sensitivity maps and body...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2009.11.003
更新日期：2010-04-01 00:00:00
abstract：:Tissue contrast obtained using fast spin-echo (FSE) and conventional spin-echo (SE) sequences is not identical and a number of mechanisms are thought to contribute to these contrast differences. The effect of stimulated echoes has previously been apparently ruled out as a contributing mechanism. Signal-to-noise ratios...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(95)02110-f
更新日期：1996-01-01 00:00:00
abstract：:Glioblastoma Multiforme is the most common and most aggressive type of brain tumors. Although accurate prediction of Glioblastoma borders and shape is absolutely essential for neurosurgeons, there are not many in silico platforms that can make such predictions. In the current study, an automatic patient-specific simul...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2019.12.012
更新日期：2020-05-01 00:00:00
abstract：:With the aim of developing a fast algorithm for high-quality MRI reconstruction from undersampled k-space data, we propose a novel deep neural Network, which is inspired by Iterative Shrinkage Thresholding Algorithm with Data consistency (NISTAD). NISTAD consists of three consecutive blocks: an encoding block, which m...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2020.04.016
更新日期：2020-07-01 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：PURPOSE:To establish an optimized sequence design for fast acceleration of arterial spin labeling (ASL)-based time-resolved magnetic resonance angiography (MRA) by acquisition of control and labeled images in the same shot (fast ACTRESS) and a scan time of <1min, for the evaluation of intracranial vessels. MATERIALS A...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2017.07.026
更新日期：2017-11-01 00:00:00
abstract：:The fluorine nuclear magnetic resonance spin-lattice relaxation rate (1/T1) of the perfluorochemical blood substitute perfluorotripropylamine (FTPA) is very sensitive to oxygen tension. This presents the possibility of measuring blood oxygen tension by 19F MR imaging. We obtained oxygen-sensitive 19F NMR images of the...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(87)90005-1
更新日期：1987-01-01 00:00:00
abstract：:The localization of critical structures within the brain is important for the planning of therapeutic strategies. Functional MRI is capable to assess functional response of cortical structures to certain stimuli. The authors present two techniques for functional MRI (fMRI) in a stereotactic set-up. The skull of the pa...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(96)02108-x
更新日期：1996-01-01 00:00:00
abstract：:Automatic segmentation of different types of tissue from magnetic resonance images is of great importance for clinical and research applications, particularly large-scale and longitudinal studies of brain pathology. We developed a fully automated algorithm for the segmentation of lateral ventricles from cranial magnet...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2006.08.013
更新日期：2006-12-01 00:00:00
abstract：:A new approach is introduced for non-rigid registration of a pair of magnetic resonance images (MRI). It is a generalization of the demons algorithm with low computational cost, based on local information augmentation (by integrating multiple images) and balanced implementation. Specifically, a single deformation that...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2020.09.013
更新日期：2020-12-01 00:00:00
abstract：:Magnetic resonance imaging (MRI) has been applied to assess kidney function in normal rats by monitoring the passage of the extracellular contrast agent GdDOTA. High-resolution images have been obtained using either the rapid acquisition with relaxation enhancement (RARE) or the snapshot pulse sequence. The latter was...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(00)00134-x
更新日期：2000-06-01 00:00:00
abstract：:Arterial spin labeling (ASL) perfusion fMRI data differ in important respects from the more familiar blood oxygen level-dependent (BOLD) fMRI data and require specific processing strategies. In this paper, we examined several factors that may influence ASL data analysis, including data storage bit resolution, motion c...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2007.07.003
更新日期：2008-02-01 00:00:00
abstract：:We report initial NMR studies of continuous flow laser-polarized xenon gas, both in unrestricted tubing, and in a model porous media. The study uses Pulsed Gradient Spin Echo-based techniques in the gas-phase, with the aim of obtaining more sophisticated information than just translational self-diffusion coefficients....
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(03)00156-5
更新日期：2003-04-01 00:00:00
