Publications
74 results found
Morrell G, Kaggie J, Stein M, et al., 2016, Rapid high-resolution sodium relaxometry in human breast, ISMRM 24th Annual Meeting
Bangerter NK, Kaggie JD, Taylor MD, et al., 2016, Sodium MRI radiofrequency coils for body imaging, NMR in Biomedicine, Vol: 29, Pages: 107-118, ISSN: 0952-3480
<jats:p>The proliferation of high‐field whole‐body systems, advances in gradient performance and refinement of signal‐to‐noise ratio (SNR)‐efficient short‐TE sequences suitable for sodium imaging have led to a resurgence of interest in sodium imaging for body applications. With this renewed interest has come increased demand for SNR‐efficient sodium coils. Efficient coils can significantly increase SNR in sodium imaging, allowing higher resolutions and/or shorter scan times. In this work, we focus on body imaging applications of sodium MRI, and review developments in MRI radiofrequency (RF) coil topologies for sodium imaging. We first provide a brief discussion of RF coil design considerations in sodium imaging. This is followed by an overview of common coil topologies, their advantages and disadvantages, and examples of each. Copyright © 2015 John Wiley & Sons, Ltd.</jats:p>
Abraham CL, Bangerter NK, McGavin LS, et al., 2015, Accuracy of 3D dual echo steady state (DESS) MR arthrography to quantify acetabular cartilage thickness, Journal of Magnetic Resonance Imaging, Vol: 42, Pages: 1329-1338, ISSN: 1053-1807
<jats:sec><jats:title>Purpose</jats:title><jats:p>To deploy and quantify the accuracy of 3D dual echo steady state (DESS) MR arthrography with hip traction to image acetabular cartilage. Clinical magnetic resonance imaging (MRI) sequences used to image hip cartilage often have reduced out‐of‐plane resolution and may lack adequate signal‐to‐noise to image cartilage.</jats:p></jats:sec><jats:sec><jats:title>Materials and Methods</jats:title><jats:p>Saline was injected into four cadaver hips placed under traction. 3D DESS MRI scans were obtained before and after cores of cartilage were harvested from the acetabulum; the two MRIs were spatially aligned to reference core positions. The thickness of cartilage cores was measured under microscopy to serve as the reference standard. 3D reconstructions of cartilage and subchondral bone were generated using automatic and semiautomatic image segmentation. Cartilage thickness estimated from the 3D reconstructions was compared to physical measurements using Bland–Altman plots.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>As revealed by the automatic segmentation mask, saline imbibed the joint space throughout the articulating surface, with the exception of the posteroinferior region in two hips. Locations where air bubbles were introduced and regions of suspected low density bone disrupted an otherwise smooth automatic segmentation mask. Automatic and semiautomatic segmentation yielded a bias ± repeatability coefficient (95% limits of agreement) of 0.10 ± 0.51 mm (−0.41 to 0.61 mm) and 0.06 ± 0.43 mm (−0.37 to 0.49 mm), respectively.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>Cartilage thickness can be estimated to within ∼0.5 mm of the physical value with 95% conf
Wang H, Bangerter NK, Park DJ, et al., 2015, Comparison of centric and reverse‐centric trajectories for highly accelerated three‐dimensional saturation recovery cardiac perfusion imaging, Magnetic Resonance in Medicine, Vol: 74, Pages: 1070-1076, ISSN: 0740-3194
<jats:sec><jats:title>Purpose</jats:title><jats:p>Highly undersampled three‐dimensional (3D) saturation‐recovery sequences are affected by k‐space trajectory since the magnetization does not reach steady state during the acquisition and the slab excitation profile yields different flip angles in different slices. This study compares centric and reverse‐centric 3D cardiac perfusion imaging.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>An undersampled (98 phase encodes) 3D ECG‐gated saturation‐recovery sequence that alternates centric and reverse‐centric acquisitions each time frame was used to image phantoms and in vivo subjects. Flip angle variation across the slices was measured, and contrast with each trajectory was analyzed via Bloch simulation.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Significant variations in flip angle were observed across slices, leading to larger signal variation across slices for the centric acquisition. In simulation, severe transient artifacts were observed when using the centric trajectory with higher flip angles, placing practical limits on the maximum flip angle used. The reverse‐centric trajectory provided less contrast, but was more robust to flip angle variations.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>Both of the k‐space trajectories can provide reasonable image quality. The centric trajectory can have higher CNR, but is more sensitive to flip angle variation. The reverse‐centric trajectory is more robust to flip angle variation. Magn Reson Med 74:1070–1076, 2015. © 2014 Wiley Periodicals, Inc.</jats:p></jats:sec>
Wang H, Bangerter NK, Chen L, et al., 2015, Radial CAIPIRINHA for Rapid 6 Slice Myocardial Perfusion Without Magnetization Preparation, ISMRM 23rd Annual Meeting & Exhibition
Kaggie J, Thapa B, Sapkota N, et al., 2015, Synchronous sodium (23Na) and proton (1H) radial imaging of the human knee on a clinical MRI scanner, ISMRM 23rd Annual Meeting
Nazaran A, Kaggie J, Taylor M, et al., 2015, An SNR Comparison Between a Sodium Phased Array Coil and a Single Channel Coil, ISMRM 23rd Annual Meeting
Wang H, Bangerter N, Chen L, et al., 2015, Radial CAIPIRINHA for rapid 6 slice myocardial perfusion without magnetization preparation, ISMRM 23rd Annual Meeting
Jordan CD, McWalter EJ, Monu UD, et al., 2014, Variability of CubeQuant T1ρ, quantitative DESS T2, and cones sodium MRI in knee cartilage, Osteoarthritis and Cartilage, Vol: 22, Pages: 1559-1567, ISSN: 1063-4584
Kaggie JD, Hadley JR, Badal J, et al., 2014, A 3 T Sodium and Proton Composite Array Breast Coil, MAGNETIC RESONANCE IN MEDICINE, Vol: 71, Pages: 2231-2242, ISSN: 0740-3194
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- Citations: 35
Wang H, Bangerter N, Kholmovski EG, et al., 2014, Dark rim artifacts from motion in highly accelerated 3D cardiac perfusion imaging, ISMRM 22nd Annual Meeting
Park DJ, Bangerter N, Morrell GR, 2014, Decoupled RF-pulse phase sensitive B1 mapping, ISMRM 22nd Annual Meeting
Taylor M, Wang H, Badal J, et al., 2014, Relaxometry and Contrast Optimization for Laryngeal Imaging at 3 Tesla, ISMRM 22nd Annual Meeting
Mendoza MA, Villalpando R, Park DJ, et al., 2014, Water Fat Separation with Multiple-Acquisition bSSFP, ISMRM 22nd Annual Meeting
Kaggie JD, Sapkota N, Jeong K, et al., 2014, Synchronous 1 H and 23 Na dual-nuclear MRI on a clinical MRI system, equipped with a time-shared second transmit channel, ISMRM 22nd Annual Meeting
Wang H, Bangerter N, Adluru G, et al., 2014, Myocardial perfusion imaging with an interleaved multi-slice acquisition for steady-state readout without saturation preparation or gating, ISMRM 22nd Annual Meeting
Kogan F, Rosenberg J, McWalter EJ, et al., 2014, Quantitative MRI of Osteoarthritis for Multicenter Trials: Standardization between Different Centers and Manufacturers, ISMRM 22nd Annual Meeting
Park DJ, Bangerter NK, Javed A, et al., 2013, A statistical analysis of the Bloch–Siegert<i>B</i><sub>1</sub>mapping technique, Physics in Medicine and Biology, Vol: 58, Pages: 5673-5691, ISSN: 0031-9155
Jordan CD, Saranathan M, Bangerter NK, et al., 2013, Musculoskeletal MRI at 3.0T and 7.0T: A comparison of relaxation times and image contrast, European Journal of Radiology, Vol: 82, Pages: 734-739, ISSN: 0720-048X
Wang H, Bangerter N, Schabel M, et al., 2013, Whole Brain Dynamic Contrast-Enhanced Imaging via Compressed Sensing Techniques, ISMRM 21st Annual Meeting
Kaggie JD, Hadley JR, Badal J, et al., 2013, A 3T Sodium and Proton Breast Array, ISMRM 21st Annual Meeting
Jordan CD, Monu UD, McWalter EJ, et al., 2013, CubeQuant T1rho, QDESS T2, and Cones Sodium Measurements Are Sufficiently Reproducible for In Vivo Cartilage Studies, ISMRM 21st Annual Meeting
Muelly M, Watkins RD, Jordan C, et al., 2013, Comparison of Multi Nuclear Coil Designs for 1H and 23Na in the Human Knee, ISMRM 21st Annual Meeting
Wang H, Bangerter N, Adluru G, et al., 2013, Centric and Reverse-Centric Trajectories for Undersampled 3D Saturation Recovery Cardiac Perfusion Imaging, ISMRM 21st Annual Meeting
Quist B, Hargreaves BA, Cukur T, et al., 2012, Simultaneous fat suppression and band reduction with large‐angle multiple‐acquisition balanced steady‐state free precession, Magnetic Resonance in Medicine, Vol: 67, Pages: 1004-1012, ISSN: 0740-3194
<jats:title>Abstract</jats:title><jats:p>Balanced steady‐state free precession (bSSFP) MRI is a rapid and signal‐to‐noise ratio‐efficient imaging method, but suffers from characteristic bands of signal loss in regions of large field inhomogeneity. Several methods have been developed to reduce the severity of these banding artifacts, typically involving the acquisition of multiple bSSFP datasets (and the accompanying increase in scan time). Fat suppression with bSSFP is also challenging; most existing methods require an additional increase in scan time, and some are incompatible with bSSFP band‐reduction techniques. This work was motivated by the need for both robust fat suppression and band reduction in the presence of field inhomogeneity when using bSSFP for flow‐independent peripheral angiography. The large flip angles used in this application to improve vessel conspicuity and contrast lead to specific absorption rate considerations, longer repetition times, and increased severity of banding artifacts. In this work, a novel method that simultaneously suppresses fat and reduces bSSFP banding artifact with the acquisition of only two phase‐cycled bSSFP datasets is presented. A weighted sum of the two bSSFP acquisitions is taken on a voxel‐by‐voxel basis, effectively synthesizing an off‐resonance profile at each voxel that puts fat in the stop band while keeping water in the pass band. The technique exploits the near‐sinusoidal shape of the bSSFP off‐resonance spectrum for many tissues at large (>50°) flip angles. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc.</jats:p>
Wang H, Bangerter N, Adluru G, et al., 2012, Comparison of highly accelerated TV and low rank methods for breast DCE data, ISMRM 20th Annual Meeting
Kaggie JD, Campbell JR, Badal J, et al., 2012, A Sodium Phased Array Breast Coil with Hydrogen Transceive, ISMRM 20th Annual Meeting
Park DJ, Javed A, Bangerter N, et al., 2012, Practical SAR Constraints of the Bloch-Siegert B1 Mapping Method at 3T, ISMRM 20th Annual Meeting
Bangerter NK, Cukur T, Hargreaves BA, et al., 2011, Three-dimensional fluid-suppressed T2-prep flow-independent peripheral angiography using balanced SSFP, Magnetic Resonance Imaging, Vol: 29, Pages: 1119-1124, ISSN: 0730-725X
Allen SP, Morrell GR, Peterson B, et al., 2011, Phase‐sensitive sodium <i>B</i><sub>1</sub> mapping, Magnetic Resonance in Medicine, Vol: 65, Pages: 1125-1130, ISSN: 0740-3194
<jats:title>Abstract</jats:title><jats:p>Quantitative sodium MRI requires accurate knowledge of factors affecting the sodium signal. One important determinant of sodium signal level is the transmit <jats:italic>B</jats:italic><jats:sub>1</jats:sub> field strength. However, the low signal‐to‐noise ratio typical of sodium MRI makes accurate <jats:italic>B</jats:italic><jats:sub>1</jats:sub> mapping in reasonable scan times challenging. A new phase‐sensitive <jats:italic>B</jats:italic><jats:sub>1</jats:sub> mapping technique has recently been shown to work better than the widely used dual‐angle method in low‐signal‐to‐noise ratio situations and over a broader range of flip angles. In this work, the phase‐sensitive <jats:italic>B</jats:italic><jats:sub>1</jats:sub> mapping technique is applied to sodium, and its performance compared to the dual‐angle method through both simulation and phantom studies. The phase‐sensitive method is shown to yield higher quality <jats:italic>B</jats:italic><jats:sub>1</jats:sub> maps at low signal‐to‐noise ratio and greater consistency of measurement than the dual‐angle method. An in vivo sodium <jats:italic>B</jats:italic><jats:sub>1</jats:sub> map of the human breast is also shown, demonstrating the phase‐sensitive method's feasibility for human studies. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.</jats:p>
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