Anastasia Fotaki¹, Kuberan Pushparajah¹, Reza Hajhosseiny¹, Alina Schneider¹, Karl Kunze^1,2, Radhouene Neji^1,3, Harith Alam⁴, Alessandra Frigiola⁴, René Botnar^1,5, and Claudia Prieto^1,5
1Biomedical Engineering, King's College London, London, United Kingdom, ²MR Research Collaborations, Siemens Healthcare Limited, Frimley, United Kingdom, ³MR Research Collaborations, Siemens Healthcare Limited, London, United Kingdom, ⁴Guy’s and St Thomas’s Hospital, London, United Kingdom, ⁵Escuela de Ingeniería, Pontificia Universidad Católica de Chile, Santiago, Chile

A recently developed sequence, the  Magnetisation Transfer Contrast Bright Blood phase SensiTive (MTC-BOOST), enables free-breathing simultaneous acquisition of a bright-blood and black-blood 3D whole-heart dataset. We sought to compare the acquisition time, image quality and diagnostic performance of the proposed MTC-BOOST against the native clinical T2-prep bSSFP and the contrast-enhanced (CE) T2-prep bSSFP sequence in a cohort of patients with Congenital Heart Disease. Our study showed that MTC-BOOST offers good delineation of the intracardiac and vascular anatomy that is comparable to the clinical CE T2prep bSSFP and superior to the non-CE T2-prep bSSFP while offering a shorter acquisition time.

Alexander Isaak¹, Narine Mesropyan¹, Christopher Hart², Dmitrij Kravchenko¹, Christoph Endler¹, Leon M. Bischoff¹, Shuo Zhang³, Christoph Katemann³, Oliver Weber³, Daniel Kuetting¹, Ulrike Attenberger¹, Darius Dabir¹, and Julian A. Luetkens^1
1Department of Diagnostic and Interventional Radiology, University Hospital Bonn, Bonn, Germany, ²Department of Diagnostic and Interventional Radiology & Department of Pediatric Cardiology, University Hospital Bonn, Bonn, Germany, ³Philips GmbH Market DACH, Hamburg, Germany

Application of high-resolution 3D MR angiography (MRA) in small children with congenital heart disease (CHD) is challenging and generally requires contrast agent administration. In a cohort of pediatric CHD patients (median age: 4 years), non-contrast-enhanced free-breathing gated 3D mDixon REACT-MRA provided comparable overall image quality to contrast-enhanced free-breathing 3D mDixon steady-state MRA for assessment of the thoracic vasculature. REACT-MRA allowed for accurate and reliable vessel size measurements. Although fat-water separation artifacts were observed, they could be extenuated by reconstruction of in- and out-of-phase images. Gated REACT-MRA allows for a contrast-free assessment of the thoracic vasculature in small children with CHD.

Reza Hajhosseiny^1,2, Adam Hartley², Graham Cole², Camila Munoz¹, Amarjit Sethi², Rasha Al-Lamee², Deepa Gopalan², Ben Ariff², Raffi Kaprielian², Karl Kunze^3,4, Radhouene Neji^3,4, Claudia Prieto¹, Ramzi Khamis², and René M Botnar^1
1Biomedical Engineering Department, School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom, ²National Heart and Lung Institute, Imperial College London, London, United Kingdom, ³MR Research Collaborations, Siemens Healthcare Limited, Frimley, United Kingdom, ⁴School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom

CMR plaque imaging has the potential to predict future coronary events, but is limited by low spatial-resolution, misregistration artefacts, respiratory motion related image quality degradation and unpredictable acquisition times. Here we clinically evaluate the feasibility of a novel 3D free-breathing, non-rigid motion corrected, non-contrast CMR sequence (iT2prep-BOOST) that enables simultaneous, high-resolution visualisation of the coronary arteries and high-risk plaque features on co-registered bright and black blood images in patients presenting with acute myocardial infarction. We found that iT2prep-BOOST can simultaneously visualise coronary artery stenosis as well as culprit and bystander coronary plaque, as validated against invasive coronary angiography and OCT.

Liliana E. Ma^1,2, Haben Berhane^1,2, Justin Baraboo^1,2, Michael Sugimura³, Christopher W. Roy⁴, Mariana Falcão⁴, Jérôme Yerly⁴, Matthias Stuber^4,5, and Michael Markl^1,2
1Department of Radiology, Northwestern University, Feinberg School of Medicine, Chicago, IL, United States, ²Department of Biomedical Engineering, Northwestern University, Evanston, IL, United States, ³Self-employed, Chicago, IL, United States, ⁴Department of Radiology, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland, ⁵Center for Biomedical Imaging, Lausanne, Switzerland

Recently, a free-running 5D flow framework was introduced and validated. However, some 5D flow MRI is based on 3D radial imaging, which is limited by reduced SNR that can result in challenges with 3D segmentation. A number of previous studies have investigated automatic segmentation for 4D flow MRI, however these have been traditionally optimized for Cartesian datasets, which are typically acquired over much smaller spatial matrices and cover only one respiratory position. The purpose of this study was thus to adapt and expand a deep-learning framework to cardiac 5D flow MRI data for automatic segmentation of the thoracic aorta.

Javier Montalt-Tordera¹, Endrit Pajaziti¹, Rod Jones², Jennifer Steeden¹, Silvia Schievano¹, and Vivek Muthurangu^1
1University College London, London, United Kingdom, ²Great Ormond Street Hospital, London, United Kingdom

Computational fluid dynamics (CFD) are useful in the assessment of blood flow conditions in patients with congenital heart disease. A necessary, time-consuming step in the creation of CFD models is the segmentation of the anatomy of interest. In this work, a neural network was trained to segment the aorta and the pulmonary arteries in 3D MRI, and its performance was evaluated in the context of a CFD application. The network performs well in terms of Dice score and is shown to lead to accurate pressure and flow velocity fields, with errors at the level of inter-observer variability.

Giulia M.C. Rossi¹, Ludovica Romanin^1,2, Mariana B.L. Falcão¹, Bastien Milani¹, Davide Piccini^1,2, Jérôme Yerly^1,3, Jürg Schwitter^4,5,6, Milan Prša⁷, Tobias Rutz⁸, Estelle Tenisch¹, Matthias Stuber^1,3, and Christopher W. Roy^1
1Department of Radiology, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland, ²Advanced Clinical Imaging Technology (ACIT), Siemens Healthcare AG, Lausanne, Switzerland, ³CIBM Center for Biomedical Imaging, Lausanne, Switzerland, ⁴Division of Cardiology, Lausanne University Hospital (CHUV), Lausanne, Switzerland, ⁵Director CMR-Center, Lausanne University Hospital (CHUV), Lausanne, Switzerland, ⁶Faculty of Biology and Medicine, University of Lausanne (UNIL), Lausanne, Switzerland, ⁷Division of Pediatric Cardiology, Woman-Mother-Child Department, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland, ⁸Service of Cardiology, Heart and Vessel Department, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland

Free-running whole-heart MRI can suffer from flow artifacts. Despite the efficiency of 3D radial UTE in minimizing the latter, its integration as a free-running sequence has so far been challenging due to poor-quality self-gating, which has necessitated an inefficient dual-echo approach. In this work we show that self-gating signals from a single-echo ferumoxytol-enhanced free-running 3D radial UTE sequence are comparable to the dual-echo approach, allowing to significantly improve scanning efficiency and produce dynamic images that are free from flow artifacts.

Mohamed Nagiub¹, Madhusudan Ganigara¹, Bharti Sharma¹, René Botnar², Tarique Hussain¹, and Joshua S Greer^1
1Pediatrics, UT Southwestern Medical Center, Dallas, TX, United States, ²Biomedical Engineering, King's College London, London, United Kingdom

3D bSSFP is the standard for anatomical evaluation of congenital heart disease, but provides suboptimal visualization of the pulmonary veins due to off resonance and flow. Solutions have been proposed to reduce the sensitivity of the bSSFP acquisition to these factors with limited success. However, the T2prep pulse that is routinely applied for bSSFP imaging also likely contributes to pulmonary vein signal loss. In this study, we compare multiple contrast preparation schemes for 3D bSSFP imaging which minimize sensitivity of off-resonance to improve pulmonary vein visualization.