Electronic Posters: Cardiovascular

Wednesday 13:30-15:30 Computer 42

13:30 3781. Accelerated Time Resolved Inflow with 3D Multi-Echo Radial Trajectories

Kevin M . Johnson¹, Oliver Wieben^1,2, Patrick Turski², Charles Mistretta<sup>1

1</sup>Medical Physics, University of Wisconsin - Madison, Madison, WI, United States; ²Radiology, University of Wisconsin - Madison, Madison, WI, United States

Arterial spin labeling (ASL) sequences which utilize tagging schemes to images the flow of blood have emerged as effective techniques for the non-contrast angiography; however, these techniques typically suffer from long acquisition times, sensitivity to tag delay parameters, and uncertain performance in cases of complex flow . To mitigate these errors, we investigate the utilization of highly accelerated, dynamic inflow imaging utilizing efficient, short TR 3D radial bSSFP sequences.

14:00 3782. Non-Contrast Enhanced Pulmonary Vein MRA with Compressed Sensing

Mehmet Akçakaya^1,2, Peng Hu², Vahid Tarokh¹, Warren J. Manning², Reza Nezafat<sup>2

1</sup>Harvard University, Cambridge, MA, United States; ²Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States

Non-contrast pulmonary vein (PV) MR angiography (MRA) is an alternative to the clinical contrast-enhanced technique. We have recently developed a non-contrast PV MRA technique using a sagittal selective inversion pulse. However, the resulting acquisition time is significantly longer than breath-hold contrast-enhanced technique. In this study, we investigate the feasibility of using compressed sensing for accelerating data acquisition in non-contrast PV MRA. We use a distributed compressed sensing technique to reconstruct separate coil images simultaneously. We show that this reconstruction yields good results even at high rates (x10).

14:30 3783. Non-Contrast Inversion Recovery Balanced Ssfp Mra of the Abdominal Aorta at 3T: Predicting Optimal Inversion Times by Blood Velocity Measurement

Iliyana Plamenova Atanasova^1,2, Ruth P. Lim¹, Hua Guo¹, Daniel Kim¹, Pippa Storey¹, Kellyanne McGorty¹, Andrew Laine², Vivian S. Lee<sup>1

1</sup>Department of Radiology, New York University, New York, United States; ²Columbia University, New York, United States

3D non-enhanced balanced steady-state free precession MRA with a slab-selective inversion (IR SSFP) has demonstrated promise for renal artery evaluation at 1.5T. With proper selection of inversion times (TI), the technique can be adopted for coronal imaging of the abdominal aorta with comprehensive superior-inferior coverage at 3T. We propose a method for subject-specific calculation of TI based on arterial blood velocities. Our results illustrate that visualization of the aortoiliac vessels using IR SSFP varies considerably across subjects depending on flow velocities. Thus, measuring aortic velocities prior to MRA enables an examination tailored to the patient’s physiology for improved arterial visualization.

15:00 3784. MRI Determined Carotid Artery Flow Velocities and Wall Shear Stress in a Mouse Model of Vulnerable and Stable Atherosclerotic Plaque

Gustav Jacob Strijkers¹, Glenda S. van Bochove¹, Roel Straathof¹, Rob Krams², Klaas Nicolay<sup>1

1</sup>Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands; ²Department of Bioengineering, London Imperial College, London, United Kingdom

We report here on the pre-clinical MRI characterization of an apoE-/- mouse model of stable and vulnerable carotid artery atherosclerotic plaques, which were induced by a tapered restriction (cast) around the artery. Specific focus was on the quantification of flow velocities and wall shear stress (WSS), which are considered key players in the development of the plaque phenotype.