Jana Vincent^1,2,3, Clyve Konrad Follante¹, Ersin Bayram⁴, Lloyd Estkowski⁵, Ty Cashen⁶, Mark Giancola¹, Victor Taracila¹, Yun-Jeong Stickle¹, Lalit Rai¹, Venkata Malasani¹, Nicole Wake^7,8, Vichiry Yan¹, Robert Stormont⁹, Joseph Rispoli^2,10, and Fraser Robb^1
1GE Healthcare Coils, Aurora, OH, United States, ²Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, United States, ³Basic Medical Sciences, Purdue University, West Lafayette, IN, United States, ⁴Global MR Applications & Workflow, GE Healthcare, Houston, TX, United States, ⁵Global MR Applications & Workflow, GE Healthcare, Waukesha, WI, United States, ⁶Global MR Applications and Workflow, GE Healthcare, Madison, WI, United States, ⁷Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, NY, United States, ⁸Center for Advanced Imaging Innovation and Research, Department of Radiology, NYU School of Medicine, New York, NY, United States, ⁹GE Healthcare, Waukesha, WI, United States, ¹⁰School of Electrical & Computer Engineering, Purdue University, West Lafayette, IN, United States

Typically, breast MR scans are performed prone; however, there are advantages to supine imaging. Here we present the first 60-channel, high-resolution, flexible breast coil. The coil can be run with the embedded posterior coil for a total of 90-channels in the FOV. In addition to better image quality, with such a high channel count, an acceleration of up to 5 by 2 was possible. Due to the structured shape, breast tissue was kept in place for the duration of the scan and women with cup sizes up to a DD could be accommodated. Straps provide adjustments for smaller bust sizes.

Yunsuo Duan¹, Jiacheng Wang², Feng Liu¹, Rachel Marsh¹, and Thomas J. Vaughan^3
1MR Research, Department of Psychiatry, NYSPI and Columbia University, New York, NY, United States, ²Department of Electrical Engineering, New York University, New York, NY, United States, ³ZMBBI, Columbia University, New York, NY, United States

Close fitting is extremely crucial for RF coil arrays in order to maximize sensitivity. It is impossible to closely fit for all subjects of various head sizes using rigid head coil arrays. We presented a novel design of partially flexible 32-channel coil array to address the issue. The inner dimensions of the coil array can be smoothly adjusted from 180mmx220mm to 220mmx 260 mm, which fit for almost all head sizes of adult human subjects. The experiment results showed high imaging quality within the adjustable ranges. The coil array is highly practical for both research and clinical settings.

Jo Lee^1,2, Sen Jia^1,2, Liu Liu³, Xiaoliang Zhang⁴, and Ye Li^1,2
1Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China, ²Shenzhen Key Laboratory for MRI, Shenzhen, China, ³United Imaging Healthcare, Shanghai, China, ⁴Department of Biomedical Engineering, State University of New York, Buffalo, NY, United States

We designed and built a quadrature-birdcage/ 47Rx head coil array for accelerated images on 3 T MRI. A 32-channel commercial head coil was used as a comparison. The inverse g-factor images and accelerated anatomical images both show that the 47-channel head coil has better acceleration ability. EPI images and cerebrovascular images further verified that the 47-channel head coil is capable of human’s brain studies.

Nikos Priovoulos¹, Thomas Roos¹, Ozlem Ipek², Ettore Meliado³, Richard Nkrumah², Dennis Klomp³, and Wietske van der Zwaag^1
1Spinoza Center, Amsterdam, Netherlands, ²King’s College London, London, United Kingdom, ³University Medical Center Utrecht, Utrecht, Netherlands

The function of human cerebellum is underexplored in vivo, due to its small size and its placement at the bottom of the brain where transmit fields are suboptimal at 7Tesla. Here, we combined 2 dense coil arrays of 16 small surface receive elements each with a transmit array of 3 antennas elements. Our results show improved B₁+ and SNR close to the surface as well as g-factor gains compared to a whole-head commercial coil. This resulted in large gains in the surface (< 3.5cm) in the spatial extent of the BOLD activation, at the cost of increased signal inhomogeneity.

Byung-Pan Song^1,2, Sung-Jun Yoon¹, Hyeong-Seop Kim^1,2, Kyoung-Nam Kim³, and Seung-Kyun Lee^1,2,4,5
1Department of Biomedical Engineering, Sungkyunkwan University, Suwon, Korea, Republic of, ²Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon, Korea, Republic of, ³Department of Biomedical Engineering, Gachon University, Incheon, Korea, Republic of, ⁴Department of Physics, Sungkyunkwan University, Suwon, Korea, Republic of, ⁵IBS Center for Neuroscience Imaging Research, Suwon, Korea, Republic of

MR microscopy can provide high-resolution measurement of MR properties of biological and artificial tissues that can be compared with optical imaging. In such experiments, low signal-to-noise ratios (SNR) of a common clinical RF coil with a low filling factor will be a challenge. So, we propose a novel, multi-turn histology coil  for imaging microscopic tissue histology slices with substantially higher SNR in clinical MRI scanner compared to the previous design for microscopy tissue imaging.

Anpreet Ghotra¹, Sam-Luca JD Hansen¹, Robin Etzel¹, Mirsad Mahmutovic¹, Alina Scholz¹, Nicolas Kutscha¹, Matthäus Poniatowski¹, Markus W May¹, Choukri Mekkaoui², and Boris Keil^1
1Institute of Medical Physics and Radiation Protection, TH Mittelhessen University of Applied Sciences, Giessen, Germany, ²Harvard Medical School, Massachusetts General Hospital, Department of Radiology, A.A. Martinos Center for Biomedical Imaging, Boston, MA, United States

Even with commonly used k-space subsampling acceleration methods, cardiac MRI still suffers from relatively slow acquisition speed which imposes limitations in spatial and temporal resolution and volumetric coverage when imaging the moving heart. The recently introduced simultaneous multi-slice (SMS) acceleration technique offers the potential to acquire multiple slices which can substantially increase myocardial coverage without compromising in-plane spatial resolution. However, to disentangle the collapsed slices, array coils must provide enough sensitivity variation along the slice direction. Therefore, in this simulation study, we evaluated the coverage of the cardiac array coil to maximize SMS encoding performance.

Wahidul Alam¹, Rushdi Zahid Rusho¹, Scott Reineke², Madavan Raja², Stanley Kruger³, Joseph M. Reinhardt¹, Junjie Liu⁴, Douglas Van Daele⁵, and Sajan Goud Lingala^1,2
1Roy J Carver Department of Biomedical Engineering, University of Iowa, iowa city, IA, United States, ²ScanMed LLC, Omaha, NE, United States, ³Department of Radiology, University of Iowa, iowa city, IA, United States, ⁴Department of Neurology, University of Iowa, iowa city, IA, United States, ⁵Department of Otolaryngology, University of Iowa, iowa city, IA, United States

We develop a novel custom airway coil that offers significant boost in signal sensitivity in several regions of the upper-airway such as tongue, soft-palate, pharynx, glottis. Our coil is designed to be flexible for easy conformation to the subjects face/neck anatomy. With the proposed coil, we demonstrate robust parallel MRI performance up to R=4-5 fold for static imaging with 1-D under-sampling, and highly accelerated dynamic imaging (up to R~27 fold) of swallowing, and airway shaping due to variations in breathing. 
 

Mohammed M. Albannay¹, Charles McGrath¹, Alexander Jaffray¹, and Sebastian Kozerke^1
1University and ETH Zurich, Institute for Biomedical Engineering, Zurich, Switzerland

 In this work SNR of thermal and hyperpolarized MRI is simulated based on first principles. It is demonstrated that detection of hyperpolarized nuclei is more favourable at lower field strengths (e.g. 0.75T) where prolonged T₂* values and reduced readout bandwidth lead to higher SNR compared to standard clinical field strengths. Moreover, SNR benefits of receive coil cooling are experimentally studied on a clinical 3T Philips Achieva scanner that has been ramped down to a field strength of 0.75T.
 

Lena Nohava^1,2, Andre Kuehne³, Elmar Laistler¹, and Sigrun Roat^1
1High Field MR Center, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria, ²BioMaps (Laboratoire d'Imagerie Biomédicale Multimodale Paris Saclay), Université Paris-Saclay, CEA, CNRS, Inserm, Orsay, France, ³MRI.TOOLS GmbH, Berlin, Germany

In this work, we investigated the performance differences between a flexible single-gap coaxial coil operated far above self-resonance and a double-gap coaxial coil operated on self-resonance at 7T. Based on electromagnetic simulations and MRI results it is demonstrated that in the single-gap design the current distribution on the outside of the coaxial shield is strongly inhomogeneous. This leads to a strong dependence of the Tx performance on the coil orientation relative to B₀. In contrast, the double-gap design results in homogeneous current distribution and orientation-independent Tx performance.

Christoph Michael Schildknecht¹ and Klaas Paul Pruessmann^1
1Institute for Biomedical Engineering, ETH Zurich and University of Zurich, Zürich, Switzerland

In this work, additive manufacturing of MRI coils by selectively electroplating a conductive polymer is demonstrated, enabling the fabrication of complex coil geometries with high accuracy and reproducibility. Using a low-cost multi-material FDM 3D printer, deposition of insulating and conductive elements has been achieved in a single process, followed by straightforward electroplating. The proposed approach is demonstrated by an example of a wrist coil, including in-vivo imaging at 3T.

Chang-Hoon Choi¹, Suk-Min Hong¹, Jörg Felder¹, Lutz Tellmann¹, Jürgen Scheins¹, Elena Rota Kops¹, Christoph Lerche¹, and N. Jon Shah^1,2,3,4
1INM-4, Forschungszentrum Juelich, Juelich, Germany, ²JARA-BRAIN-Translational Medicine, Aachen, Germany, ³Department of Neurology, RWTH Aachen University, Aachen, Germany, ⁴INM-11, Forschungszentrum Juelich, Juelich, Germany

Hybrid MR-PET is a powerful imaging technique that capitalised on the advantages of both modalities. However, to optimise these capabilities, the MRI antenna, which is located inside the effective PET detection area, needs to be operated without compromising any aspects of system performance or image quality compared to the stand-alone instrumentation. Here, we report a novel J-pole antenna array concept which is gamma radiation transparent. Furthermore, this unique feature provides advantages in MR-only applications by reducing the coupling effect between cables and the antenna elements and by lowering the potential specific absorption rate burden.

Ilias Giannakopoulos¹, Georgy Dmitrievich Guryev², Jose Enrique Cruz Serralles², Ioannis Georgakis¹, Luca Daniel², Jacob White², and Riccardo Lattanzi^1,3,4
1Center for Advanced Imaging Innovation and Research (CAI2R), Department of Radiology, New York University Grossman School of Medicine, New York, NY, United States, ²Department of Electrical & Computer Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States, ³The Bernard and Irene Schwartz Center for Biomedical Imaging (CBI), Department of Radiology, New York University Grossman School of Medicine, New York, NY, United States, ⁴Vilcek Institute of Graduate Biomedical Sciences, New York University Grossman School of Medicine, New York, NY, United States

The volume-surface integral equation (VSIE) method is used for rapid and accurate simulations of electromagnetic fields in magnetic resonance imaging. For the case of a 7T array and a numerical head phantom, we constructed the VSIE coupling matrix that models the interactions between the coil and the scatterer. We reshaped the columns of the matrix as incomplete 3D tensors. We investigated how the low rank properties of these tensors, could be exploited to compress the coupling matrix, by expressing the tensors in their canonical form. We showed that an excellent compression could be achieved with an error lower than 2%.

Yosuke Otake¹, Takeshi Taniguchi¹, Hideta Habara¹, Christophor Napier², Errol Brissett², Shawn Etheridge², Masayoshi Dohata¹, and Kazuyuki Kato^1
1Healthcare Business Unit, Hitachi, Ltd., Tokyo, Japan, ²Hitachi Healthcare Americas, Twinsburg, OH, United States

To improving the SNR and the usability in the vertical field MRI(Open MRI), a flexible body(spine/torso) coil has been developed. The coil consists of loop/CRC hybrid multi-channel array (LCA). The performance of the coil was evaluated in phantom experiment at 1.2T vertical field MRI. The SNR of the coil using LCA was 46% better than a conventional body coil. This technique will contribute to improve the performance of the vertical field MRI.

Ming Lu^1,2, Junzhong Xu^1,2, Sandeep S. Arora³, John C. Gore^1,2, and Xinqiang Yan^1,2
1Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, United States, ²Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, United States, ³Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, United States

Prostate cancer is one of the leading causes of cancer death among men in the US. MRI is a useful tool to assess the presence and extent of prostate cancer, and diagnostic accuracy relies on acquiring images with high SNR. We aimed to improve the performance of such arrays by using flexible coaxial coil technology and an over-overlapping layout to increase the number of coil elements without sacrificing coil size.

Jonathan Cuthbertson^1,2, Trong-Kha Truong^1,2, Jasmine Chen^1,2, Fraser Robb³, Allen W. Song^1,2, and Dean Darnell^1,2
1Medical Physics Graduate Program, Duke University, Durham, NC, United States, ²Brain Imaging Analysis Center, Duke University, Durham, NC, United States, ³GE Healthcare, Aurora, OH, United States

The integrated RF/wireless coil design allows for simultaneous MR image acquisition and wireless data transfer with the same coil element in order to reduce the number of wired connections in the scanner. Here, we use this coil design to wirelessly transmit the scanner trigger signal to perform the Q-spoiling required for MR imaging. Proof-of-concept experiments in a phantom showed that this coil design was able to accurately and reliably transmit the scanner trigger from the adjacent console room to a WiFi-enabled module in the scanner bore, while having minimal impact on the image SNR or wireless performance.

Yun-Jeong Stickle¹, Clyve Konrad Follante¹, Mark Giancola¹, David Anderson¹, Fraser Robb¹, Thomas Stickle¹, Robert Stormont², Holly Blahnik², Ho-Joon Lee³, Young Han Lee⁴, and Darryl B. Sneag^5
1GE Healthcare Coils, Aurora, OH, United States, ²GE Healthcare, Waukesha, WI, United States, ³Haeundae Paik Hospital, Busan, Korea, Republic of, ⁴Severance hospital, Yonsei University, Seoul, Korea, Republic of, ⁵Hospital for Special Surgery, New York, NY, United States

Conventional high density phased-array head/neck coils are designed to tightly conform to head/neck region to increase SNR and accommodate higher acceleration, which in turn limits space and their use for larger patients. This study shows results for two different universally sized AIR (Adaptive Imaging Receive) neck/cervical spine coils combined with a 48-Channel head coil to provide higher SNR and improved acceleration compared to a conventional coil. 3T MRI setups to image the head/neck, carotids and cervical spine were designed and constructed. Phantom measurements and high-resolution in vivo imaging were performed to demonstrate design performance.

Bijaya Thapa^1,2, Bernhard Strasser^1,2, Xianqi Li^1,2, Jason Stockman^1,2, Azma Mareyam¹, Boris Keil³, Zhe Wang⁴, Stefan Carp^1,2, Yulin V. Chang⁴, Lawrence Wald^1,2, Philipp Hoecht Hoecht⁵, and Ovidiu Andronesi^1,2
1Dept. of Radiology, MGH, A. A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States, ²Harvard Medical School, Boston, MA, United States, ³Mittelhessen University of Applied Science, Giessen, Germany, ⁴Siemens Medical Solutions USA, Charlestown, MA, United States, ⁵Siemens Healthcare, Erlangen, Germany

An Electronic REference To access In vivo Concentrations (ERETIC) to absolutely quantify the brain metabolites for 3D-MRSI using an array coil was developed. The challenge of ERETIC for large receive arrays is that the addition of many ERETIC channels might negatively impact B0 and B1 homogeneity and increase the unwanted channel cross-talk. Here we investigated whether the number of ERETIC channels can be reduced below the number of RF receive  elements. We also developed a unique method to coil combine the ERETIC and receive array signal.  Metabolite concentration maps obtained with ERETIC were compared to internal water reference  method.

José Antonio BERNARDO¹, Abel Rangel Trejo¹, Lucas Werling², Wilfried Uhring², Luc Hebrard², Youssef Zaim Wadghiri³, Christian Gontrand⁴, and Latifa Antonio Fakri-bouchet^5
1Univ Lyon, CNRS, Université Claude Bernard Lyon 1, Institut des Sciences Analytiques, UMR 5280, Villeurbanne, France, ²Icube Laboratory, UMR –CNRS 7357, Université de Strasbourg, Strasbourg, France, ³Grossman School of Medicine, New York University, New York, NY, United States, ⁴INL(Institut des nanotechnologies de Lyon), INSA (Institut National des Sciences Appliquées) Lyon, CNRS, Université Claude Bernard Lyon1, Villeurbanne Cedex, France, ⁵Univ Lyon, CNRS, Université Claude Bernard Lyon 1, Institut des Sciences Analytiques, UMR 5280, INSA Lyon (Institut National des Sciences Appliquées), Villeurbanne, France

In this study, we propose an original modelling platform 3D-TLE (Transmission Line Extractor)  to determine NMR coil and microcoil performance from their geometry. Each part of our microcoil (region of interest \((ROI \sim 2µL-3µL))\), active part, Transmission Line (TL), micro-wire connection (underpass-vias) and the substrate is modelled by an electrical circuit and each contribution to the equivalent resistance is quantified. Our platform allows predicting the optimized microcoil geometry related to expected performances in terms of \(Q-factor\) and the signal-to-noise ratio \((SNR)\).  

Tijl van der Velden¹, Mark Gosselink¹, Ingmar Voogt², Martijn Froeling¹, Hans Hoogduin¹, Dennis Klomp¹, Bart Steensma¹, and Alexander Raaijmakers^1,3
1UMC Utrecht, Utrecht, Netherlands, ²Wavetronica, Utrecht, Netherlands, ³Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands

In this study we investigate the parallel imaging performance of a 72 channel body array for 7 tesla. G-factor maps and T2w prostate images have been acquired in a healthy volunteer. Accelerations of 3x3 and 4x1 are feasible without detrimental g-factor penalties.

Michael Obermann¹, Sigrun Roat¹, and Elmar Laistler^1
1High Field MR Center, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria

Close form-fitting and adaptation of the RF coil array to the target anatomy are key for obtaining high SNR. We combine ultra-flexible coaxial coils with a modular setup to achieve form-fitting by coil flexibility and adaptive coverage of the assembled array through modularity. In this work, the robustness of the coil characteristics upon reconfiguration of three modules in different array arrangements, was investigated and demonstrated its feasibility without compromise in coil performance.