Ahsan Javed¹, Rajiv Ramasawmy¹, Kendall O’Brien¹, Christine Mancini¹, Pan Su², Waqas Majeed², Thomas Benkert³, Himanshu Bhat², Anthony F. Suffredini⁴, Ashkan Malayeri⁵, and Adrienne E Campbell-Washburn^1
1Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, United States, ²Siemens Medical Solutions USA Inc., Malvern, PA, United States, ³Siemens Healthcare GmbH, Erlangen, Germany, ⁴Critical Care Medicine Department, Clinical Center, National Institutes of Health, Bethesda, MD, United States, ⁵Department of Radiology and Imaging Sciences, Clinical Center, Department of Health and Human Services, National Institutes of Health, Bethesda, MD, United States

High-performance 0.55T MRI is promising for lung imaging due to the reduced susceptibility artifacts. However, high-resolution lung imaging is still challenged by low proton density and SNR. 3D spiral acquisitions can be used to improve SNR-efficiency, but these readouts are susceptible to trajectory errors and blurring from concomitant-fields, which are amplified at lower field strengths. Here we present a self-gated, ultra-short echo-time, stack-of-spirals acquisition which leverages rapid inline corrections for trajectory imperfections, trajectory dependent navigator signal fluctuations, and concomitant-fields to enable robust 1.75mm isotropic lung imaging at 0.55T. We also demonstrate our technique in healthy-volunteers, patients with lung-nodules and COVID-19.

Emil Ljungberg^1,2, Tobias C. Wood¹, Ana Beatriz Solana³, Steven C.R. Williams¹, Gareth J. Barker¹, and Florian Wiesinger^1,3
1Department of Neuroimaging, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, London, United Kingdom, ²Department of Medical Radiation Physics, Lund University, Lund, Sweden, ³GE Healthcare, Munich, Germany

We present a new method called MERLIN for motion corrected silent neuroimaging using zero echo time (ZTE) MRI. Self-navigation is achieved with an interleaved 3D spiral phyllotaxis trajectory to produce image navigators. Retrospective motion correction is then applied to the collected raw data. The acoustic noise of MELIN was less than 4 dBA above ambient levels. A range of different head motion paradigms were evaluated (rotation and nodding), showing greatly improved image quality after motion correction in all cases.

Sai Abitha Srinivas^1,2, Stephen F Cauley^3,4, Jason P Stockmann^3,4, Charlotte R Sappo^1,2, Christopher E Vaughn^1,2, Lawrence Wald^3,4,5, William Grissom^1,2,6,7, and Clarissa Cooley^3,4
1Vanderbilt University Institute of Imaging Science, Nashville, TN, United States, ²Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, United States, ³Harvard Medical School, Boston, MA, United States, ⁴Dept. of Radiology, Massachusetts General Hospital, Athinoula A Martinos Center for Biomedical Imaging, Boston, MA, United States, ⁵Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA, United States, ⁶Department of Electrical Engineering, Vanderbilt University, Nashville, TN, United States, ⁷Department of Radiology, Vanderbilt University, Nashville, TN, United States

Point of care MRI requires operation outside of an MR shielded room where electromagnetic interference can degrade image quality. To address this, we demonstrate a self-calibrated generalized dynamic model to retrospectively remove time-varying external interference. The method uses data acquired from multiple Electromagnetic Interference (EMI) detectors simultaneous with the primary MR coil. We test the approach both in a controlled EMI setting on an 80mT Halbach scanner and an uncontrolled real-world EMI setting on a 47.5mT permanent magnet open MRI system.

Nan Meng^1,2, Ting Fang^1,2, Pengyang Feng³, Zhun Huang³, Jing Sun⁴, Xuejia Wang⁵, Jie Shang⁶, Kaiyu Wang⁷, Dongming Han⁵, and Meiyun Wang^1,2
1Department of Medical Imaging, Zhengzhou University People’s Hospital & Henan Provincial People’s Hospital, Zhengzhou, China, ²Academy of Medical Sciences, Zhengzhou University, Zhengzhou, China, ³Department of Medical Imaging, Henan University People’s Hospital & Henan Provincial People’s Hospital, Zhengzhou, China, ⁴Department of Pediatrics, Zhengzhou Central Hospital, Zhengzhou University, Zhengzhou, China, ⁵Department of MR, the First Affiliated Hospital, Xinxiang Medical University, Weihui, China, ⁶Department of Pathology, the First Affiliated Hospital, Xinxiang Medical University, Weihui, China, ⁷MR Research China, GE Healthcare, Beijing, China

Intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI) can fully reflect the information of water molecular diffusion, microcirculation perfusion, and tissue heterogeneity. Amide proton transfer-weighted imaging (APTWI) has unique advantages in displaying mobile proteins and polypeptides. Our results showed that IVIM, DKI, and APTWI can estimate the risk stratification of early-stage (FIGO ≤ I) endometrial carcinoma (EC), and the combination of D, MK, and MTRasym (3.5 ppm) may be an effective imaging marker for identifying low-risk and non-low-risk early-stage EC.

Jonathan A. Pan¹, Austin A. Robinson², Patricia Rodriguez Lozano¹, Yang Yang³, Stephen McHugh⁴, Eric M. Holland⁵, Craig H. Meyer^6,7, Angela M. Taylor¹, Christopher M. Kramer^1,7, and Michael Salerno^8
1Cardiovascular Division, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States, ²Division of Cardiovascular Diseases, Division of Radiology, Scripps Clinic, La Jolla, CA, United States, ³Biomedical Engineering and Imaging Institute and Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, United States, ⁴Department of Internal Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States, ⁵Division of Cardiology, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States, ⁶Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, United States, ⁷Department of Radiology and Medical Imaging, University of Virginia Health System, Charlottesville, VA, United States, ⁸Division of Cardiovascular Medicine, Stanford University, Palo Alto, CA, United States

Variable density spiral (VDS) pulse sequences with motion compensated compressed sensing reconstruction allow for whole-heart quantitative assessment of myocardial perfusion but have not yet been clinically validated. In this study, we showed that whole-heart VDS stress perfusion has good diagnostic accuracy and ischemic burden evaluation. No significant difference was seen between visual and quantitative diagnostic performance and ischemic burden measurements.

Mariya S. Pravdivtseva¹, Franziska Gaidzik², Philipp Berg², Carson Hoffman³, Leonardo A. Rivera-Rivera³, Rafael Medero⁴, Lindsay Bodart³, Alejandro Roldan-Alzate⁴, Michael A. Speidel³, Kevin M. Johnson³, Oliver Wieben³, Olav Jansen⁵, Jan-Bernd Hövener¹, and Naomi Larsen^5
1Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein (UKSH), Kiel University, Kiel, Germany, ²Laboratory of Fluid Dynamics and Technical Flows, Forschungs campus STIMULATE, University of Magdeburg, Magdeburg, Germany, ³Department of Medical Physics and Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States, ⁴Department of Mechanical Engineering and Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States, ⁵Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein, Kiel, Germany

An intracranial aneurysm is a life-threatening disease. Vessel-wall enhancement on black-blood MRI was associated with inflammation and proposed as a marker for higher aneurysm rupture risk. However, slow blood flow can mimic wall enhancement. Here, we studied the effects of flow rates, spatial resolution, and motion-sensitized driven equilibrium (MSDE) on black-blood MRI using printed aneurysm models. A hyperintense signal was observed in the models and co-localized with a slow flow. MSDE and higher flow rates reduced the hyperintensities. Slow-flow phenomena contribute substantially to aneurysm enhancement, vary with MRI parameters, and should be considered in rupture assessment.