Dan Ma¹, Eric Y. Pierre², Yun Jiang ², Mark D. Schluchter³, Kawin Setsompop⁴, Vikas Gulani¹, and Mark Griswold^1
1Radiology, Case Western Reserve University, Cleveland, OH, United States, ²Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States, ³Epidemiology & Biostatistics, Case Western Reserve University, Cleveland, OH, United States, ⁴A.A Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, United States

An acquisition method named MRF-Music is proposed to mitigate the acoustic noise during MRI scans by producing musical sounds directly from the switching magnetic fields while simultaneously quantifying multiple important tissue properties. MP3 music files were converted to arbitrary encoding gradients, which were then used with varying flip angles and TRs in both 2D and 3D MRF exam to generate T1, T2 and proton density maps. The MRF-Music scans were shown to significantly improve patients’ comfort. T1 and T2 measured from phantom and in vivo scans were also in good agreement with those from the standard measurements and reported values. 

Angus Zoen Lau^1,2, Jack Miller^2,3, Matthew D Robson¹, and Damian J Tyler^1,2
1Cardiovascular Medicine, University of Oxford, Oxford, United Kingdom, ²Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom, ³Department of Physics, Clarendon Laboratory, Oxford, United Kingdom

Assessment of cardiac metabolism and perfusion using hyperpolarized ¹³C substrates enables discrimination between viable, hibernating, and non-viable tissue, but current methods require two separate injections of pre-polarized [1-¹³C]pyruvate and ¹³C-urea, respectively. We propose to use an infusion of co-polarized [1-¹³C]pyruvate/¹³C-urea combined with a flow-sensitized pulse sequence to simultaneously assess both of these parameters in a single injection. Perfusion and metabolic state are modulated using specific interventions, and subsequently detected using the new scan. This probe of both myocardial perfusion and metabolism is anticipated to enable metabolic study of the heart in acute scenarios.

Zhiyong Zhang¹, Amir Seginer¹, and Lucio Frydman^1
1Chemical Physics, Weizmann Institute of Science, Rehovot, Israel

Single-shot MRI has been constrained to acquisitions in quality magnets and homogeneous tissues. The present study introduces a methodology that can deliver such images with good SNR, under much poorer field and/or multiple shift conditions. These capabilities are achieved based on new principles whereby images are read using field gradients that are not applied along the direction being encoded. This enables one to accommodate shifts/inhomogeneities into the single-scan image generation protocol, without suffering from miss-registrations, without requiring a priori information for post-acquisition corrections, and without demanding specialized instrumentation. This enables new single-shot investigations that have hitherto escaped from MRI’s scope.

Ziyue Wu^1,2, Weiyi Chen¹, Michael C.K. Khoo¹, Sally L. Davidson Ward³, and Krishna S. Nayak^1
1University of Southern California, Los Angeles, CA, United States, ²Alltech Medical Systems, Solon, OH, United States, ³Children's Hospital Los Angeles, Los Angels, CA, United States

We present a method for simultaneous multi-slice airway collapsibility measurement based on sparse golden-angle radial CAIPIRINHA, with acceleration factor up to 33.3. We present data from patients with obstructive sleep apnea and normal controls.  One interesting finding is that a narrower airway site does not always correspond to higher collapsibility. This finding may be of interest to sleep surgeons. Our results also suggest that both compliance and P_close were significantly different between healthy controls and OSA patients (P<0.001), and both measures can potentially serve as biomarkers.

Devavrat Likhite¹, Promporn Suksaranjit², Ganesh Adluru¹, Nan Hu³, Cindy Weng³, Eugene Kholmovski¹, Chris McGann², Brent Wilson², and Edward DiBella^1
1Utah Center for Advanced Imaging Research, Department of Radiology, University of Utah, Salt Lake City, UT, United States, ²Division of Cardiovascular Medicine, University of Utah, Salt Lake City, UT, United States,³Department of Internal Medicine, University of Utah, Salt Lake City, UT, United States

Dynamic contrast enhanced MRI is maturing as a tool in contemporary cardiovascular medicine. A self-gated method that avoids the use of ECG-gating signal has been validated by us for quantitative myocardial perfusion. Our most recent study looks at the inter-study repeatability of this quantitative self-gated method. Our findings show that the multi-slice self-gated (near-systole) approach has a comparable or better repeatability than published ECG-gated single slice studies. The purpose of this abstract is to summarize these findings from our recent work, highlighting the simplicity, ease of use and reliability of the self-gated method for quantitative myocardial perfusion.

Shruti Agarwal¹, Haris I. Sair¹, Noushin Yahyavi-Firouz-Abadi¹, Raag Airan¹, and Jay J. Pillai^1
1Division of Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, United States

One of the most important potential limitations of presurgical mapping using blood oxygen level dependent functional magnetic resonance imaging (BOLD fMRI) is the phenomenon of neurovascular uncoupling (NVU). NVU can lead to erroneous interpretation of clinical fMRI examinations. The effects of brain tumor-related NVU on task-based BOLD fMRI have been previously published. The purpose of this study is to demonstrate that the problem of brain tumor-related NVU is a significant issue with respect to resting state BOLD fMRI similar to task-based BOLD fMRI, in which signal detectability can be compromised by breakdown of normal neurovascular coupling.