Lei Zhang¹, Yongjun Tao², Xiaoqing Hu¹, Jun Wu², Xin Liu¹, and Yiu-Cho Chung^1
1Paul C. Lauterbur Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academic of Sciences, Shenzhen, Guangdong, China, ²Neurology, Peking University Shenzhen Hospital, Shenzhen, Guangdong, China

This study proposes the use of a neurovascular coil with an appropriately optimized T1w-SPACE for vessel wall imaging of intracranial and extracranial arteries in one scan. The sequence combined good blood suppression (through DANTE) and improved T1 contrast (through a flip-down pulse) to improve image quality. An optimized refocusing pulses¡¯ flip angle series for T1w-SPACE and a good neurovascular coil increased the SNR needed for high spatial resolution. The method covers a volume of 212mm x 159mm x 40mm with an isotropic spatial resolution of 0.6mm in 7.5min. The patient study showed that the method would be clinically relevant.

Shuqian Zhang¹, Kazuyuki Yahagi², li liu¹, Jiadi Xu³, Frank D Kolodgie², Renu Virmani², Babara Crain⁴, Bruce A Wasserman¹, and Ye Qiao^1
1Radiolgoy, Johns Hopkins, Baltimore, MD, United States, ²CVPath Institute, Inc., Gaithersburg, MD, United States, ³Kennedy Krieger Institute, MD, United States, ⁴Pathology, Johns Hopkins, Baltimore, MD, United States

Characterization of intracranial atherosclerotic plaques using ultrahigh-resolution MRI ex vivo

Jin Liu¹, Marina S. Ferguson¹, Jinnan Wang², Daniel S. Hippe¹, Niranjan Balu¹, William S. Kerwin¹, Thomas S. Hatsukami¹, and Chun Yuan^1
1University of Washington, Seattle, WA, United States, ²Philips Research North America, NY, United States

Intraplaque hemorrhage (IPH), an important destabilizing factor in atherosclerosis progression, can be identified as hyperintensity region in Simultaneous Noncontrast Angiography and intraPlaque hemorrhage (SNAP) images. In this study, validation of SNAP in detecting IPH with histology was performed, demonstrating that SNAP can identify carotid IPH accurately in vivo. Furthermore, a threshold of 740 based on the original intensity of SNAP images were obtained by optimization, in order to detect carotid IPH automatically.

Xiaoming Bi¹, Yutaka Natsuaki¹, Zhaoyang Fan², Peter Speier³, Debiao Li², and Gerhard Laub^1
1Siemens Healthcare, Los Angeles, CA, United States, ²Cedars-Sinai Medical Center, Los Angeles, CA, United States, ³Siemens Healthcare, Erlangen, Germany

High-resolution, volumetric carotid vessel wall imaging is a promising method for the rapid assessment of plaque burden. Such an imaging procedure, however, is frequently challenged by complex motions in the carotids, including pulsation of carotid arteries, swallowing, breathing, and bulk motion of patient. The goal of this work is to develop a motion-robust, black-blood 3D carotid wall imaging technique using a stack-of-stars sampling scheme. The efficacy of using such a method is compared to the conventional carotid wall imaging with Cartesian sampling. Volunteer studies show improved image quality and vessel wall delineation using the proposed flow-sensitive dephasing prepared stack-of-stars sequence.

Yunduo Li¹, Shuo Chen¹, Zechen Zhou¹, Rui Li¹, and Chun Yuan^1,2
1Center for Biomedical Imaging Research, Beijing, Beijing, China, ²Department of Radiology, University of Washington, Seattle, Washington, United States

In this study, we presented a Velocity Selective RF pulse prepared Inversion Recovery (VSIR) technique for carotid artery vessel wall imaging. Simulation results demonstrate the feasibility of VS inversion pulse. In-vivo experiments showed that VSIR can be used for carotid vessel wall imaging. VSIR technique provides better SNR of vessel wall and CNR between lumen and vessel wall than iMSDE. However, in some cases that flow is not exactly along the velocity encoding direction, such as BIFU and ICA, VS sacrifices blood suppression efficiency. More applications on other vascular bed such as femoral artery will be evaluated in further study.

Yibin Xie^1,2, Young Jin Kim³, Jianing Pang¹, Jung-Sun Kim⁴, Qi Yang¹, Zhaoyang Fan¹, Hyuk-Jae Chang⁴, and Debiao Li^1
1Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, California, United States, ²University of California, Los Angeles, Los Angeles, California, United States, ³Department of Radiology, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea, ⁴Division of Cardiology, Yonsei Cardiovascular Center, Yonsei University College of Medicine, Seoul, Korea

Recently T1-weighted MRI with or without contrast enhancement has been used for characterizing coronary plaques showing promising prognostic value for coronary events. However the drawbacks of current protocols using conventional Cartesian acquisition and respiratory gating may hinder the clinical application of this technique due to limited anatomical coverage, low anisotropic resolution and the requirement of a separate bright-blood MRA scan. We developed a time-efficient protocol based on 3DPR with simultaneously acquired MRA to address these limitations and performed preliminary clinical validation on 11 CAD patients using CT angio, X-ray angio, and intracoronary OCT as reference.

Karla Maria Treitl¹, Stefan Maurus¹, Hendrik Kooijmann-Kurfuerst², Eva Coppenrath¹, Nora N. Kammer¹, Marcus Treitl¹, Maximilian Reiser¹, and Tobias Saam^1
1Institute for clinical radiology, LMU Munich, Munich, Bavaria, Germany, ²Philips Healthcare, Philips GmbH, Hamburg, Hamburg, Germany

FDG-PET/CT is the gold standard for the diagnosis and the monitoring of large vessel vasculitis, but it causes repetitive radiation exposure. The presented, novel, isotropic-high-resolution three-dimensional T1w TSE sequence (VISTA Volumetric ISotropic TSE Acquisition) was evaluated in 23 patients with suspected large vessel vasculitis and 25 controls. The study showed that the navigated 3D black-blood MRI technique with peripheral pulse unit triggering is able to diagnose large vessel vasculitis of the thoracic vessels in 10-12 minutes scan time. Future studies are necessary to evaluate VISTA-MRI for monitoring of anti-inflammatory therapies and to perform a comparison with PET/CT and ultrasound.

Michael C Langham¹, Benoit Desjardins¹, Erin K Englund¹, Emile R Mohler², Thomas F Floyd³, and Felix W Wehrli^1
1Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States, ²Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States, ³Anesthesiology, Stony Brook University Medical Center, Stony Brook, New York, United States

We describe a new application of 3D double-echo steady-state (DESS), allowing simultaneous acquisition of spatially-registered gray and black blood images, which have the potential to address several limitations of MR angiography. 3D DESS was used to acquire gray and black blood images of the femoropopliteal and infra-popliteal arteries in healthy volunteers and patients with peripheral artery (PAD). It is shown that high-resolution dual-contrast structural 3D DESS is able to provide detailed information on vessel wall thickening, luminal geometry and calcification. Pairing 3D DESS with non-contrast MRA has the potential to improve diagnosis of PAD.

Claudia Calcagno¹, Chiara Giannarelli², Abdallah G Motaal³, Matthias Nahrendorf⁴, Willem JM Mulder^5,6, Zahi A Fayad¹, and Gustav J Strijkers^3
1Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, United States, ²Department of Cardiology, Icahn School of Medicine at Mount Sinai, New York, NY, United States, ³Department of Biomedical Engineering and Physics, Academic Medical Center, Amsterdam, The Netherlands, Netherlands, ⁴Center for Systems Biology, Massachusetts General Hospital, Boston, Massachusetts, United States, ⁵Icahn School of Medicine at Mount Sinai, New York, NY, United States, ⁶Department of Radiology, Academic Medical Center, Amsterdam, The Netherlands, Netherlands

Enhanced endothelial permeability is a hallmark of atherosclerotic plaques at high risk for causing severe clinical events. Here we present a method to quantify plaque permeability in the aortic root of ApoE -/- mice, using self-gated DCE-MRI with compressed sensing acceleration.

Haikun Qi¹, Shuo Chen¹, Zechen Zhou¹, Jinnan Wang², Peter Koken³, Niranjan Balu⁴, and Huijun Chen^1
1Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, Beijing, China, ²Philips Research North America, Briarcliff Manor, New York, United States, ³Innovative Technologies, Research Laboratories, Philips Technologies GmbH, Hamburg, Germany, ⁴Radiology, University of Washington, Seattle, WA, United States

Dynamic contrast enhanced (DCE) MRI is important in quantifying inflammatory features of atherosclerotic plaque, and interleaved black-bright imaging technique is essential for quantitative vessel wall DCE analysis. In this study, a Large coverage HOmologous black-bright blood Interleaved imaging sequence (LaHOBBI) for vessel wall DCE MRI was proposed. The feasibility of the conducting the proposed sequence was demonstrated by in vivo experiment on carotid. The LaHOBBI sequence enables 3D large coverage, high spatial resolution vessel wall DCE imaging and 2D high temporal bright blood imaging for accurate AIF extraction, which ensures the quantitative DCE analysis and coverage of atherosclerotic plaque.