A controllable susceptibility marker for passive device tracking.


PURPOSE:To design and demonstrate a new susceptibility-based tracking device with an artifact that can be mechanically turned on and off, thus permitting tracking and imaging at the device tip with limited artifact. METHODS:The magnetic susceptibilities of readily obtainable grades of titanium and graphite were measured. Using numerical optimization, layer thicknesses for three concentric cylinders were found where the field from the graphite layer maximally cancelled the fields from titanium layers. The tracking elements were fabricated for an outer diameter of 3 mm and attached to a catheter to show feasibility of detection in phantoms and in vivo. RESULTS:The device was successfully integrated into a 9F catheter, and its use with conventional guidewires under fluoroscopy was demonstrated by guiding the catheter through the bifurcation into the carotid artery. MR images including the catheter tip were acquired with the device in both the "on" and "off" positions. CONCLUSION:A new passive tracking device with a susceptibility effect that can be enabled and disabled by sliding one of the components was designed, fabricated, and demonstrated in phantoms and in vivo. The device may also be integrated into many different interventional MR devices such as needles, ultrasound transducers for prostate biopsy, or any catheter-based devices.


Magn Reson Med


Dominguez-Viqueira W,Karimi H,Lam WW,Cunningham CH




Has Abstract


2014-07-01 00:00:00












  • A comprehensive approach for correcting voxel-wise b-value errors in diffusion MRI.

    abstract:PURPOSE:In diffusion MRI, the actual b-value played out on the scanner may deviate from the nominal value due to magnetic field imperfections. A simple image-based correction method for this problem is presented. METHODS:The apparent diffusion constant (ADC) of a water phantom was measured voxel-wise along 64 diffusio...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Lee Y,Kettinger AO,Wilm BJ,Deichmann R,Weiskopf N,Lambert C,Pruessmann KP,Nagy Z

    更新日期:2020-06-01 00:00:00

  • Maximum entropy and 2DFT NMR images.

    abstract::A comparison between contrast and signal-to-noise ratio (SNR), as obtained by both maximum entropy (ME) and 2DFT reconstruction, is reported for NMR images. Our results show that in the ME elaboration the contrast and SNR are generally increased with respect to the 2DFT elaboration. The magnitude of such an increase d...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: De Simone BC,De Luca F,Maraviglia B

    更新日期:1988-11-01 00:00:00

  • Single-shot half k-space high-resolution gradient-recalled EPI for fMRI at 3 Tesla.

    abstract::Half k-space gradient-recalled echo-planar imaging (GR-EPI) is discussed in detail. T2* decay during full k-space GR-EPI gives rise to unequal weighting of the lines of k-space, loss of signal intensity at the center of k-space, and a point-spread function that limits resolution. In addition, the long readout time for...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Jesmanowicz A,Bandettini PA,Hyde JS

    更新日期:1998-11-01 00:00:00

  • High resolution quantitative relaxation and diffusion MRI of three different experimental brain tumors in rat.

    abstract::The potential of quantitative parameter images of the relaxation times T1 and T2, the proton density rho and the apparent diffusion coefficient (ADC) to characterize three different experimental rat brain tumors (F98 glioma, RN6 Schwannoma, and E376 neuroblastoma) was studied. All parameter values, as determined in hi...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Eis M,Els T,Hoehn-Berlage M

    更新日期:1995-12-01 00:00:00

  • A numerical approach to non-circular birdcage RF coil optimization: verification with a fourth-order coil.

    abstract::It is demonstrated that birdcage resonators, satisfying conditions of quadrature operation and radiofrequency field homogeneity, can be realized in practice on formers of non-circular cross section described by an equation of the form (x/a)n + (y/b)n = 1 where a and b are constants and n > or = 2 is an integer. Using ...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Riauka TA,De Zanche NF,Thompson R,Vermeulen FE,Capjack CE,Allen PS

    更新日期:1999-06-01 00:00:00

  • Trajectory optimization based on the signal-to-noise ratio for spatial encoding with nonlinear encoding fields.

    abstract:PURPOSE:Multiple nonlinear gradient fields offer many potential benefits for spatial encoding including reduced acquisition time, fewer artefacts and region-specific imaging, although designing a suitable trajectory for such a setup is difficult. This work aims to optimize encoding trajectories for multiple nonlinear g...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Layton KJ,Kroboth S,Jia F,Littin S,Yu H,Zaitsev M

    更新日期:2016-07-01 00:00:00

  • Evaluation of MRI resolution affecting trabecular bone parameters: determination of acceptable resolution.

    abstract::The objective of this study is to evaluate the effect of MR image resolution on trabecular bone parameters and to determine the acceptable resolution that can be accurately analyzed to assess structural parameters. Ten distal femoral condyle specimens of 1 × 1 × 1 cm(3) were scanned with a 4.7-T Bruker BioSpec MRI sca...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Kim N,Lee JG,Song Y,Kim HJ,S Yeom J,Cho G

    更新日期:2012-01-01 00:00:00

  • Simple analytical dual-band spectral-spatial RF pulses for B(1) + and susceptibility artifact reduction in gradient echo MRI.

    abstract::Susceptibility artifacts and transmission radio frequency (RF) field (B(1) +) inhomogeneity are major limitations in high-field gradient echo MRI. Previously proposed numerical 2D spectral-spatial RF pulses have been shown to be promising for reducing the through-plane signal loss susceptibility artifact by incorporat...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Yang C,Deng W,Stenger VA

    更新日期:2011-02-01 00:00:00

  • Contributions of chemical exchange to T1ρ dispersion in a tissue model.

    abstract::Variations in T(1ρ) with locking-field strength (T(1ρ) dispersion) may be used to estimate proton exchange rates. We developed a novel approach utilizing the second derivative of the dispersion curve to measure exchange in a model system of cross-linked polyacrylamide gels. These gels were varied in relative compositi...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Cobb JG,Xie J,Gore JC

    更新日期:2011-12-01 00:00:00

  • A new susceptibility-weighted image reconstruction method for the reduction of background phase artifacts.

    abstract:PURPOSE:To significantly reduce the background phase effects, especially at the air-tissue interface, and to enhance the desirable local structures of veins in susceptibility-weighted imaging. METHODS:In the proposed reconstruction method called Magnitude of Complex Filtering, a complex-valued magnetic resonance image...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Lee Y,Han Y,Park H

    更新日期:2014-03-01 00:00:00

  • Integrated volume-selective/spectral editing 1H NMR and postdetection signal processing for the sensitive determination of lactate.

    abstract::A new volume selection/spectral editing pulse sequence (VOSING) is presented. The features specific to the technique are that the volume selection and the editing intervals coincide and that no decoupling is necessary. The pulse sequence can be applied under both homo- and heteronuclear conditions. Phantom experiments...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Knüttel A,Rommel E,Clausen M,Kimmich R

    更新日期:1988-09-01 00:00:00

  • Metabolic markers of neuronal injury correlate with SIV CNS disease severity and inoculum in the macaque model of neuroAIDS.

    abstract::In vivo MR spectroscopy (MRS) studies have shown reductions in NAA/Cr levels in patients with severe neurocognitive deficits due to AIDS dementia complex (ADC), also known as neuroAIDS. The relationship between the cellular changes within the brain during neuroAIDS and the role of NAA/Cr as a metabolic marker remains ...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Lentz MR,Westmoreland SV,Lee V,Ratai EM,Halpern EF,González RG

    更新日期:2008-03-01 00:00:00

  • Variable density incoherent spatiotemporal acquisition (VISTA) for highly accelerated cardiac MRI.

    abstract:PURPOSE:For the application of compressive sensing to parallel MRI, Poisson disk sampling (PDS) has been shown to generate superior results compared with random sampling methods. However, due to its limited flexibility to incorporate additional constraints, PDS is not readily extendible to dynamic applications. Here, w...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Ahmad R,Xue H,Giri S,Ding Y,Craft J,Simonetti OP

    更新日期:2015-11-01 00:00:00

  • 1H NMR relaxation measurements of human tissues in situ by spatially resolved spectroscopy.

    abstract::Spatially resolved spectroscopy (SPARS) is a method for obtaining high-resolution NMR spectra of well-defined volumes of human tissues in situ. This method was combined with the Carr-Purcell-Meiboom-Gill multiple-echo sequence for T2, and with inversion recovery for T1 relaxation measurements. Relaxation times obtaine...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Luyten PR,Anderson CM,den Hollander JA

    更新日期:1987-05-01 00:00:00

  • Accelerated MR parameter mapping with low-rank and sparsity constraints.

    abstract:PURPOSE:To enable accurate magnetic resonance (MR) parameter mapping with accelerated data acquisition, utilizing recent advances in constrained imaging with sparse sampling. THEORY AND METHODS:A new constrained reconstruction method based on low-rank and sparsity constraints is proposed to accelerate MR parameter map...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Zhao B,Lu W,Hitchens TK,Lam F,Ho C,Liang ZP

    更新日期:2015-08-01 00:00:00

  • In vivo dynamic MRI tracking of rat T-cells labeled with superparamagnetic iron-oxide particles.

    abstract::Dynamic MRI tracking of rat T-cells in vivo is performed in rat testicles after labeling isolated rat T-cells in vitro with superparamagnetic dextran-coated iron-oxide particles, BMS180549. Tissue inflammation induced by the local injection of the calcium ionophore, A23187, is used to attract labeled T-cells. Gradient...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Yeh TC,Zhang W,Ildstad ST,Ho C

    更新日期:1995-02-01 00:00:00

  • Designing parallel transmit head coil arrays based on radiofrequency pulse performance.

    abstract:PURPOSE:A new approach to design parallel transmit (pTx) head arrays is proposed that integrates transmit radiofrequency pulse designs with electromagnetic modeling of array coil elements. THEORY AND METHODS:An approach to design pTx head arrays is proposed that finds optimal groupings of a large number of coils into ...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Cao Z,Yan X,Gore JC,Grissom WA

    更新日期:2020-06-01 00:00:00

  • The analytic theory, optimization, and performance of transparent pulses.

    abstract::Transparent pulses are defined by the property of having no net effect on stationary spins, while selectively nutating and dephasing flowing spins. They are derived from the inverse scattering transform, a nonlinear extension of the inverse Fourier transform. They can be used as presaturation pulses to suppress select...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Buonocore MH

    更新日期:1992-04-01 00:00:00

  • Fast measurement of blood T1 in the human carotid artery at 3T: Accuracy, precision, and reproducibility.

    abstract:PURPOSE:To develop a fast protocol for measuring T1 values in the internal carotid artery (ICA), to validate this technique with in vitro measurements, and to evaluate its reproducibility. METHODS:A modified Look-Locker sequence was optimized to enable rapid determination of T1 in the ICA at 3T. T1 values from the ICA...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Li W,Liu P,Lu H,Strouse JJ,van Zijl PCM,Qin Q

    更新日期:2017-06-01 00:00:00

  • Introduction of the snake antenna array: Geometry optimization of a sinusoidal dipole antenna for 10.5T body imaging with lower peak SAR.

    abstract:PURPOSE:To improve imaging performance for body MRI with a local transmit array at 10.5T, the geometry of a dipole antenna was optimized to achieve lower peak specific absorption rate (SAR) levels and a more uniform transmit profile. METHODS:Electromagnetic simulations on a phantom were used to evaluate the SAR and ...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Steensma B,van de Moortele PF,Ertürk A,Grant A,Adriany G,Luijten P,Klomp D,van den Berg N,Metzger G,Raaijmakers A

    更新日期:2020-11-01 00:00:00

  • MRI: the development of T2 contrast with rapid field echo sequences.

    abstract::The soft tissue contrast obtained in fast imaging using rapidly repeated partial saturation sequences is usually based on differences in T1. We describe here an extension of the method which results in the development of clinically useful T2-based contrast. ...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Young IR,Payne JA,Collins AG,Bydder GM

    更新日期:1987-04-01 00:00:00

  • Analysis and correction of motion artifacts in diffusion weighted imaging.

    abstract::For diffusion-weighted magnetic resonance imaging and under circumstances where patient movement can be modeled as rigid body motion, it is shown both theoretically and experimentally that translations and rotations produce phase errors which are zero- and first-order, respectively, in position. While a navigator echo...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Anderson AW,Gore JC

    更新日期:1994-09-01 00:00:00

  • Pulmonary edema induced by allergen challenge in the rat: noninvasive assessment by magnetic resonance imaging.

    abstract::The course of pulmonary edema formation after an intratracheal (i.t.) instillation of ovalbumin was followed noninvasively by magnetic resonance imaging (MRI) in actively sensitized Brown Norway (BN) rats. Changes in edema volume assessed by MRI mimicked the results from the analysis of the number and activation of in...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Beckmann N,Tigani B,Ekatodramis D,Borer R,Mazzoni L,Fozard JR

    更新日期:2001-01-01 00:00:00

  • Commutator filter: a novel technique for the identification of structures producing significant susceptibility inhomogeneities and its application to functional MRI.

    abstract::A robust postprocessing method to detect regions of magnetic field change is presented. High resolution gradient echo data is acquired to create a complex baseline image. From this image, two low resolution images are obtained by applying a low pass filter on the magnitude image and the complex image, respectively. Su...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Lai S,Reichenbach JR,Haacke EM

    更新日期:1996-11-01 00:00:00

  • Multicenter validation of spin-density projection-assisted R2-MRI for the noninvasive measurement of liver iron concentration.

    abstract:PURPOSE:Magnetic resonance imaging (MRI)-based techniques for assessing liver iron concentration (LIC) have been limited by single scanner calibration against biopsy. Here, the calibration of spin-density projection-assisted (SDPA) R2-MRI (FerriScan®) in iron-overloaded β-thalassemia patients treated with the iron chel...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章,多中心研究


    authors: St Pierre TG,El-Beshlawy A,Elalfy M,Al Jefri A,Al Zir K,Daar S,Habr D,Kriemler-Krahn U,Taher A

    更新日期:2014-06-01 00:00:00

  • Polymer thick film technology for improved simultaneous dEEG/MRI recording: Safety and MRI data quality.

    abstract:PURPOSE:To develop a 256-channel dense-array electroencephalography (dEEG) sensor net (the Ink-Net) using high-resistance polymer thick film (PTF) technology to improve safety and data quality during simultaneous dEEG/MRI. METHODS:Heating safety was assessed with temperature measurements in an anthropomorphic head pha...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Poulsen C,Wakeman DG,Atefi SR,Luu P,Konyn A,Bonmassar G

    更新日期:2017-02-01 00:00:00

  • Safety and technique of ferumoxytol administration for MRI.

    abstract::Ferumoxytol is an ultrasmall superparamagnetic iron oxide agent marketed for the treatment of anemia. There has been increasing interest in its properties as an MRI contrast agent as well as greater awareness of its adverse event profile. This mini-review summarizes the current state of knowledge of the risks of ferum...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章,评审


    authors: Vasanawala SS,Nguyen KL,Hope MD,Bridges MD,Hope TA,Reeder SB,Bashir MR

    更新日期:2016-05-01 00:00:00

  • Spin-locking versus chemical exchange saturation transfer MRI for investigating chemical exchange process between water and labile metabolite protons.

    abstract::Chemical exchange saturation transfer (CEST) and spin-locking (SL) experiments were both able to probe the exchange process between protons of nonequivalent chemical environments. To compare the characteristics of the CEST and SL approaches in the study of chemical exchange effects, we performed CEST and SL experiment...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Jin T,Autio J,Obata T,Kim SG

    更新日期:2011-05-01 00:00:00

  • Real-time Triggered RAdial Single-Shot Inversion recovery for arrhythmia-insensitive myocardial T1 mapping: motion phantom validation and in vivo comparison.

    abstract:PURPOSE:Cardiac T1 mapping has become an increasingly important imaging technique, contributing novel diagnostic options. However, currently utilized methods are often associated with accuracy problems because of heart rate variations and cardiac arrhythmia, limiting their value in clinical routine. This study aimed to...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Gensler D,Salinger T,Düring M,Lorenz K,Jahns R,Wech T,Frantz S,Ertl G,Jakob PM,Nordbeck P

    更新日期:2019-03-01 00:00:00

  • Unaliasing by fourier-encoding the overlaps using the temporal dimension (UNFOLD), applied to cardiac imaging and fMRI.

    abstract::In several applications, MRI is used to monitor the time behavior of the signal in an organ of interest; e.g., signal evolution because of physiological motion, activation, or contrast-agent accumulation. Dynamic applications involve acquiring data in a k-t space, which contains both temporal and spatial information. ...

    journal_title:Magnetic resonance in medicine

    pub_type: 杂志文章


    authors: Madore B,Glover GH,Pelc NJ

    更新日期:1999-11-01 00:00:00