Dave Hitt¹, Jonathan Chia¹, Robert Lay¹, Tom Lowe¹, Michael Pawlak¹, John Penatzer¹, James Snicer¹, Marcie Stopchinski¹, Gregory Thomas¹, Paul Worthington¹, Kristen Williams¹, and Brian Johnson^2
1Philips Healthcare, Gainesville, FL, United States, ²3545 SW 47th Ave, Philips Healthcare, Gainesville, FL, United States

Patients with MR Conditional orthopedic implants can be challenging to scan due to susceptibility artifact from metal implants.  Use of metal artifact reduction (MARS) techniques can help reduce signal loss from metal implants, however, are not usually sufficient to allow for detailed peri-prosthetic tissue visualization.  Metal-induced field inhomogeneities cannot be accurately modeled, which is why O-MAR (MARS+VAT) can improve in-plane distortions by utilizing a more robust spatial encoding approach.  Here we present the conceptual background behind the O-MAR technique and work done to provide guidance for optimized metal reduction imaging protocols.     

Ortman Jason¹, Jennifer Wagner², Bharath Ambale¹, Yoko Kato³, Jaclyn Sesso³, Yoshimori Kassai⁴, Larry Kasuboski², and Joao Lima^3
1Radiology, Johns Hopkins University, Baltimore, MD, United States, ²Canon Medical Research Unit, Mayfield VIllage, OH, United States, ³Cardiology, Johns Hopkins University, Baltimore, MD, United States, ⁴Canon Medical Systems, Otawara-Shi, Tochigi, Japan

For respiratory triggered and gated acquisitions, variance in the natural respiratory cycle often complicates workflow, extending scan times and reducing image quality. This abstract discusses the hypothesis that by providing continuous auditory guidance, or "respiratory pacing", the efficacy of respiratory triggered and gated sequences may be improved. The importance of mimicking natural respiratory patterns was quickly noted, as were key differences in the success of respiratory pacing when applied to different acquisitions. Other interesting observations included an observable increase in diaphragmatic travel when respiratory pacing was applied and the extension of scan lengths due to diaphragmatic fatigue over time.

Mark J Burton¹, Robert Thomen¹, Talissa A. Altes¹, Carlos Leiva Salinas¹, Nicholas Tustison², and Joseph P Cousins^1
1Radiology, University of Missouri Hospital, Columbia, MO, United States, ²Radiology, University of Virginia, Charlottesville, VA, United States

This work was to assess the trade-off between scan time and image quality afforded by acceleration techniques GRAPPA and simultaneous multi-slice (SMS). We imaged an ACR phantom using standard clinical T1, T2, and FLAIR sequences. Then, without altering any other scan parameters, we increased GRAPPA and SMS acceleration factors (2, 4, and 6).  All GRAPPA and SMS accelerated scans passed the ACR resolution criteria. Both GRAPPA and SMS passed low-contrast criteria at acceleration factor 2, but factors of 4 and 6 did not. GRAPPA and SMS gave nearly identical similarity indices and SNR at all acceleration factors.  

Belinda Lokaj¹, Karen Kinkel², Jean-Noel Hyacinthe³, Jérôme Schmid³, and Céline Gaignot^3
1Master of Science in Health Sciences, HES-SO /UNIL, Lausanne, Switzerland, Lausanne, Switzerland, ²Institut de radiologie, Clinique des Grangettes, Chêne-Bougeries, Geneva, Switzerland, Geneva, Switzerland, ³Geneva School of Health Sciences, HES-SO // University of Applied Sciences and Arts of Western Switzerland, Geneva, Switzerland

Breast MRI is promoted as a tool for breast cancer screening because of its high sensitivity. Possibility of differentiating between benign and malign lesions has been studied using lesion enhancement parameters on DCE, thus helping to reduce examination time. This study was designed to verify sensitivity and specificity for lesion characterization. Time to Enhancement and Maximum Slope of the enhancement curve obtained from an ultrafast sequence were evaluated. Preliminary results tend to confirm that performing breast lesions screening using ultrafast-DCE is a valuable alternative to the standard MRI Breast protocol, possibly opening diagnostic perspectives to a wider population of women.

Hui Hao¹, Jia Yin Tong¹, Xiao Cheng Wei², Jian Xin Guo¹, and Jian Yang^1
1Department of Radiology, The first affiliated hospital of xi 'an jiaotong university, Xi'an, China, ²MR Research China, GE Healthcare, BeiJing, China

Bone metastasis is a common complication of advanced malignant tumors with severe simptoms. Common imaging modalities for bone metastasis diagnosis include X-ray, CT,MRI, SPECT, and PET. PET is the golden standard, but the nature of radiation, metabolic risk and high price have limited PET from widely clinical use. In this work, we presented 4 cases of bone metastasis which had had a difference in MRI derived fat fraction between bone metastatic vertebrae and normal non-metastatic vertebrae. MR results were also coincided with PET results. MRI derived fat fraction may be used as an imaging evaluation index for bone metastasis.

chuan bing wang¹ and da peng li^2
1Department of Radiology, the First Affiliated Hospital of Nanjing Medical University (Jiangsu Province Hospital), Nanjing, China, ²the First Affiliated Hospital of Nanjing Medical University (Jiangsu Province Hospital), nan jing, China

The aim of this study is to evaluate the volume change of breast tumor, various kinds ofspatial movementin nipple and the bottom center of the sternum origin, and distance from tumor center to the chest wall from prone to supine MRIs, and then to predict more accuracy tumor positions for surgical planning in the operation room.

Le Cao¹, Xiang Liu^1,2, and Jianxin Guo^1
1The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi,, China, ²The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi, China

3.0T MR scanner can achieve superior image quality depicting fetal anatomic details over 1.5T, but may poses higher risk of adverse impact on fetal auditory development due to its intrinsically higher acoustic noise level. This comparative study investigated the value of acoustic noise reduction technique in fetal exam. The result shows the technique can acquire equivalent quality images in 3.0T scanner, meanwhile decrease hearing loss risk in fetal head examinations compared with the conventional method.

Pradeep Singh Negi^1,2,3, Shashi Bhushan Mehta^1,2, Amarnath Jena^1,2, and Sangeeta Bhushan Taneja^1
1Molecular Imaging & Nuclear Medicine, Indraprastha Apollo Hospitals, New Delhi, India, ²Physics, Vivekananda Global University, Jaipur, India, ³PET SUITE, House of Diagnostics, New Delhi, India

Inhomogeneity in fat suppression and image distortion pose problem in Breast MRI specially in the diffusion and dynamic fat suppressed images using mMR breast coil. The purpose of this work to improve fat-superstation and minimize image distortion in the breast imaging before applying the MRI sequence specially in Dynamic fat-supressed Contrast and Diffusion images. 330 breast cancer patients have been taken for this study. Volume shim was applied in all patients and water peak shift corrected manually when required. Our results show reduction in image distortion in diffusion and improving in fat-supressed MRI images.

Kristina Mary Pelkola¹, Onur Afacan¹, Tess E. Wallace², Jason A. Ferro¹, Carol M. Backman¹, Davide Piccini^3,4,5, Tobias Kober^3,4,6, Carol E. Barnewolt¹, Susan A. Connolly¹, Judy A. Estroff², and Simon K. Warfield^1
1Radiology, Boston Children's Hospital, Boston, MA, United States, ²Boston Children's Hospital, Boston, MA, United States, ³Advanced Clinical Imaging Technology, Siemens Healthcare, Lausanne, Switzerland, ⁴Radiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland, ⁵LTS5, Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne, Switzerland, ⁶LTS5, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland

Fetal MRI is a rapidly growing field that facilitates diagnosis and treatment providing improved maternal and fetal care. New imaging strategies are needed to improve the assessment of cardiac structure and function. We assessed an interactive fetal cardiac prototype sequence enabling the fetal heart to be imaged in real-time, while prescribing the imaging plane to fetal movement. Once positioned to the long axis, a sequence of 2D radial readouts are acquired, enabling inline reconstruction of beating heart images with a frame rate between 0.5s and 1s. This new capability allowed assessment the anatomy and function of the fetal heart.

Dawn Holley¹, Kim Halbert¹, and Mehdi Khalighi^1
1Radiology, Stanford University, Stanford, CA, United States

Simultaneous PET/MR imaging is still a relatively new dual modality. As such, unique challenges are commonly faced across departments. What were once commonly separate, Nuclear Medicine and Radiology departments now need to work together to create new workflows, protocols and management systems. Questions commonly arise regarding how these two modalities and departments can best come together for management success. A survey of 19 questions was distributed to 12 different PET/MR departments in order to gain an understanding of what challenges are often faced and how to resolve them, as well as any commonalities across successful departments. 

Ho Beom Lee¹ and Kwan Woo Choi^2
1Asan Medical Center, Seoul, Republic of Korea, ²Wonkwang Health Science University, Iksan, Republic of Korea

2D High resolution PROPELLER technique was compared to 3D Fast spin echo imaging on axial and reformatted (sag and cor) images.  

Kevin Epperson¹, Karla Epperson¹, Garry Gold¹, and Feliks Kogan^1
1Radiology, Stanford University School of Medicine, Stanford, CA, United States

Diagnostic MRI scanning of the knee at 3T offers multiple contrasts and definition of anatomical structures, presenting pathology, and allows quantitative performance methods. Ultra high field (7T) systems offer improved resolution and SNR for visualization of small morphological changes and translation of quantitative methods presents challenges in field uniformity and shading artifacts which limit the robustness and clinical potential of these systems.In this work we implement a new method to overcome field inhomogeneity errors and assess the potential clinical benefits of knee imaging at 7T.

Rene Jack Roy^1
1UVA, charlottesville, VA, United States

The complexity and costs of MRI RF coil design seems out of reach for most non-physicists in the medical research field. To facilitate learning more about coil design and functionality, we have attempted to build a simple loop coil that can be used in small animal research.

Renee Mineo¹, Claire Mulcahy¹, Shawna Farquharson¹, and Alan Connely^2,3
1MRI, The Florey Institute of Neuroscience and Mental Health, Heidelberg, Australia, ²Imaging, The Florey Institute of Neuroscience and Mental Health, Heidelberg, Australia, ³Imaging, The Florey Department of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia, Melbourne, Australia

This study reviewed the engagement of MR Radiographers & Technologists with a social media platform seeking professional guidance with MR safety decision making processes regarding implants or devices. From June 2016 to August 2018 100 discussion items were reviewed and categorized. Our study identified that the ‘consensus to scan or not to scan’, was not completely dependent on the presence of detailed information about the implant or device.