Abstract：
:The local determination of porosity is an extremely valuable target because of different applications in petrophysics. In fact, obtaining a reliable profile of porosity or saturations could considerably improve the evaluation of transport properties of porous media, especially if applied to multiphase flow test (i.e., for relative permeability characterisation). However, the best procedure to adopt for these kind of studies is currently under debate, involving different experimental choices both for acquisition and hardware solutions. The choice of a reliable procedure could be particularly important especially if heterogeneous samples (i.e., vugular or fractured carbonates) are approached. We have investigated selected carbonate cores, characterised by fractures and large vugs, using different instrumental solutions in order to assess usefulness of application of NMR imaging methods as a porosity measurement tool for heterogeneous samples. Local porosity data have been obtained and discussed relative to conventional measurements and petrographical aspects of rock samples.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Borgia GC,Bortolotti V,Dattilo P,Fantazzini P,Maddinelli Gdoi
10.1016/s0730-725x(96)00182-8subject
Has Abstractpub_date
1996-01-01 00:00:00pages
919-21issue
7-8eissn
0730-725Xissn
1873-5894pii
S0730-725X(96)00182-8journal_volume
14pub_type
杂志文章abstract：:The value of NMR spectrometry as a way to understand the porosity and permeability of rocks is well documented. Other more esoteric parameters, such as restrictive diffusion, grain size distribution, and fluid viscosities have received less notice but are also available from the NMR measurements as laboratory studies ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(94)91537-7
更新日期：1994-01-01 00:00:00
abstract：:Echo planar imaging (EPI) was extended for the acquisition of both, the spin-echo (SE) and the stimulated echo in a stimulated echo sequence after one excitation from thermal equilibrium. The two independent EPI images reflect different states of the transverse magnetization excited and measured almost simultaneously....
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(94)91234-n
更新日期：1994-01-01 00:00:00
abstract：PURPOSE:Time-of-flight (ToF) and phase contrast (PC) magnetic resonance angiographies (MRAs) are noninvasive applications to depict the cerebral arteries. Both approaches can image the cerebral vasculature without the administration of intravenous contrast. Therefore, it is used in routine clinical evaluation of cerebr...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2012.10.023
更新日期：2013-05-01 00:00:00
abstract：:The evaluation of a solitary pulmonary nodule (SPN) is one of the most frequently encountered challenges in thoracic radiology. In addition to a "state-of-the-art" evaluation of SPNs with CT and biopsy techniques, recently the assessment of the enhancement characteristics with iodinized contrast agents has shown its p...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(95)02010-q
更新日期：1995-01-01 00:00:00
abstract：:The goal of this study was to determine whether presurgical metabolite levels measured by 3D MR Spectroscopic Imaging (MRSI) can accurately detect viable cancer within human brain tumor masses. A total of 31 patients (33 exams, 39 pathology correlations) with brain tumors were studied prior to surgical biopsy and/or r...
journal_title：Magnetic resonance imaging
pub_type： 临床试验,杂志文章
doi：10.1016/s0730-725x(01)00225-9
更新日期：2001-01-01 00:00:00
abstract：PURPOSE:To evaluate the performance of combined integrated slice-by-slice shimming and readout-segmented EPI (irsEPI) for diffusion-weighted MR imaging (DWI) of the neck at 3Tesla. METHODS:This study was approved by the local ethics committee. An anthropometric phantom of the head/neck region incorporating compartment...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2017.05.004
更新日期：2017-10-01 00:00:00
abstract：:Quantitative longitudinal brain magnetic resonance (MR) studies may be confounded by scanner-related drifts in voxel sizes. Total intracranial volume (TIV) normalisation is commonly used to correct serial cerebral volumetric measurements for these drifts. We hypothesised that automated rigid-body registration of whole...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2004.01.057
更新日期：2004-09-01 00:00:00
abstract：:Peripancreatic fluid collections are among the common post pancreas transplant complications, which are mainly due to leakage from the anastomosis site to bowel and graft pancreatitis. Differentiation between these two entities is important because they are treated differently. In this case, secretin stimulated magnet...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2009.02.003
更新日期：2009-09-01 00:00:00
abstract：PURPOSE:To implement and evaluate interleaved blip-up, blip-down, non-segmented 3D echo planar imaging (EPI) with pseudo-continuous arterial spin labeling (pCASL) and post-processing for reduced susceptibility artifact cerebral blood flow (CBF) maps. MATERIALS AND METHODS:3D EPI non-segmented acquisition with a pCASL ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2017.08.011
更新日期：2017-12-01 00:00:00
abstract：:The purpose of this study was to develop a method to determine time discrepancies between input and myocardial time-signal intensity (TSI) curves for accurate estimation of myocardial perfusion with first-pass contrast-enhanced MRI. Estimation of myocardial perfusion with contrast-enhanced MRI using kinetic models req...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2015.06.015
更新日期：2015-11-01 00:00:00
abstract：PURPOSE:To implement and evaluate the accuracy of non-invasive temperature mapping using MRI methods based on the chemical shift (CS) and T1 relaxation in media of various heterogeneity during focal (laser) and external thermal energy deposition. MATERIALS AND METHODS:All measurements were performed on a 1.5 T superco...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(97)00311-1
更新日期：1998-05-01 00:00:00
abstract：PURPOSE:To describe the patterns of bile distribution in the biliary tree, duodenum, jejunum, and stomach, and to determine the gallbladder ejection fraction (GBEF) by using functional magnetic resonance cholangiography (MRC) with gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (Gd-EOB-DTPA) in healthy vol...
journal_title：Magnetic resonance imaging
pub_type： 临床试验,杂志文章
doi：10.1016/j.mri.2014.01.003
更新日期：2014-05-01 00:00:00
abstract：:The application of a raw data-based, operator-independent MR segmentation technique to differentiate boundaries of tumor from edema or hemorrhage is demonstrated. A case of a glioblastoma multiforme with gross and histopathologic correlation is presented. The MR image data set was segmented into tissue classes based o...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(94)00093-i
更新日期：1995-01-01 00:00:00
abstract：:In ultrashort TE (UTE) imaging, the short T2 values of the tissues of interest are comparable to the k-space readout duration, which result in significant T2 decay during k-space readout. This decay consequently causes significant effects on signal and contrast in UTE sequences, which we evaluate in this paper using m...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2013.11.002
更新日期：2014-04-01 00:00:00
abstract：BACKGROUND:Ultra-high spatial resolution imaging of whole, ex vivo brains provides new opportunities to understand neurological disease. Recent work has demonstrated that 100 μm isotropic resolution can reveal anatomical details that are otherwise difficult to appreciate, but relied on fabrication facilities, fabricati...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2020.11.002
更新日期：2021-02-01 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：: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：:The advantages of event-related functional Magnetic Resonance Imaging (fMRI) and the increasing use of fMRI in cognitive experiments are both driving the development of techniques that allow images sensitive to the blood oxygen level-dependent effect to be acquired at ever-higher temporal resolution. Here, we present ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2005.12.030
更新日期：2006-05-01 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：:NMR offers, in the complex proton relaxation properties of biological tissues, a unique and potentially powerful tool of tissue characterization. The difficulties encountered so far in comparing the results of in vitro and in vivo NMR studies carried out in different laboratories inhibit NMR methodologies from fully e...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(88)90447-x
更新日期：1988-03-01 00:00:00
abstract：:Functional magnetic resonance imaging (fMRI) research has shown that brain arteriovenous malformations (AVMs) lead to reorganization of cortical motor areas. Since it is known that blood oxygenation level-dependent signal in fMRI may be influenced by the hemodynamic perturbation associated with the presence of the AVM...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2009.05.029
更新日期：2009-12-01 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 aim of this study was to establish a rapid method for in vivo quantification of a large range of flow velocities using phase information. A basic gradient-echo sequence was constructed, in which flow was encoded along the slice selection direction by variation of the amplitude of a bipolar gradient without changes...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(89)90535-3
更新日期：1989-11-01 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：:A fast spin echo two-point Dixon (fast 2PD) technique was developed for efficient T2-weighted imaging with uniform water and fat separation. The technique acquires two interleaved fast spin echo images with water and fat in-phase and 180 degrees out-of-phase, respectively, and generates automatically separate water an...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2005.10.005
更新日期：2005-12-01 00:00:00
abstract：:Resting fluctuations in arterial CO2 (a cerebral vasodilator) are believed to be an important source of low-frequency blood oxygenation level dependent (BOLD) signal fluctuations. In this study we focus on the two commonly used resting-states in functional magnetic resonance imaging experiments, eyes open and eyes clo...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2012.06.013
更新日期：2013-04-01 00:00:00
abstract：OBJECTIVE:In magnetic resonance-guided breast vacuum biopsies, the contrast agent for targeting suspicious lesions can typically be applied only once during an intervention, due to the slow elimination of the gadolinium chelate from the extracellular fluid space. This study evaluated the feasibility of diffusion-weight...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2016.12.006
更新日期：2017-05-01 00:00:00
abstract：:A simple model for estimating temperature distribution within the frozen region during cryo ablation was tested for accuracy. Freezing experiments were conducted in both ex vivo and in vivo porcine livers. Temperature was measured during freezing using a fiber-optic temperature sensor. Three-dimensional MR images were...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(01)00389-7
更新日期：2001-06-01 00:00:00
abstract：:The specialised radiofrequency (RF) coils used in MRI such as head or surface coils can give rise to marked image intensity nonuniformities. There are two situations in which it is essential to correct this: (1) When a global intensity threshold is used to segment particular tissues; and (2) in proton density images, ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(93)90023-7
更新日期：1993-01-01 00:00:00
abstract：:3D (kx, ky, t)-space analysis is invoked to provide insights into dynamic magnetic resonance imaging (DMRI) with arbitrary k-space sampling trajectories. The effects of 3D sampling in (kx, ky, t) are analyzed theoretically and verified with computer simulation. The analyses show that a 3D sampling pattern that is more...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2006.04.009
更新日期：2006-10-01 00:00:00
