Unsupervised Adaptive Neural Network Regularization for Accelerated Radial Cine MRI
Charité - Universitätsmedizin Berlin(夏里特大学医学院);Berlin Institute of Health(柏林健康研究所);Physikalisch-Technische Bundesanstalt (PTB)(德国联邦物理技术研究院);King’s College London(伦敦国王学院);Technical University of Berlin(柏林工业大学);University of Innsbruck(因斯布鲁克大学)
Andreas Kofler, Marc Dewey, Tobias Schaeffter, Christoph Kolbitsch, Markus Haltmeier
In this work, we propose an iterative reconstruction scheme (ALONE - Adaptive Learning Of NEtworks) for 2D radial cine MRI based on ground truth-free unsupervised learning of shallow convolutional neural networks. The network is trained to approximate patches of the current estimate of the solution during the reconstruction. By imposing a shallow network topology and constraining the $L_2$-norm of the learned filters, the network's representation power is limited in order not to be able to recover noise. Therefore, the network can be interpreted to perform a low dimensional approximation of the patches for stabilizing the inversion process. We compare the proposed reconstruction scheme to two ground truth-free reconstruction methods, namely a well known Total Variation (TV) minimization and an unsupervised adaptive Dictionary Learning (DIC) method. The proposed method outperforms both methods with respect to all reported quantitative measures. Further, in contrast to DIC, where the sparse approximation of the patches involves the solution of a complex optimization problem, ALONE only requires a forward pass of all patches through the shallow network and therefore significantly accelerates the reconstruction.
We propose a method to classify cardiac pathology based on a novel approach to extract image derived features to characterize the shape and motion of the heart. An original semi-supervised learning procedure, which makes efficient use of a large amount of non-segmented images and a small amount of images segmented manually by experts, is developed to generate pixel-wise apparent flow between two time points of a 2D+t cine MRI image sequence. Combining the apparent flow maps and cardiac segmentation masks, we obtain a local apparent flow corresponding to the 2D motion of myocardium and ventricu…
Universitat Pompeu Fabra(庞培法布拉大学);BCN MedTech(巴塞罗那医疗科技中心);Queen Mary University of London(伦敦玛丽女王大学);William Harvey Research Institute(威廉·哈维研究所);Stanford University(斯坦福大学);Catalan Institution for Research and Advanced Studies (ICREA)(加泰罗尼亚研究与高级研究所)
Use expert visualization or conventional clinical indices can lack accuracy for borderline classications. Advanced statistical approaches based on eigen-decomposition have been mostly concerned with shape and motion indices. In this paper, we present a new approach to identify CVDs from cine-MRI by estimating large pools of radiomic features (statistical, shape and textural features) encoding relevant changes in anatomical and image characteristics due to CVDs. The calculated cine-MRI radiomic features are assessed using sequential forward feature selection to identify the most relevant ones f…
United Imaging Intelligence(联影智能);UIH America, Inc.(联影美国公司)
Real-time cardiac cine MRI does not require ECG gating in the data acquisition and is more useful for patients who can not hold their breaths or have abnormal heart rhythms. However, to achieve fast image acquisition, real-time cine commonly acquires highly undersampled data, which imposes a significant challenge for MRI image reconstruction. We propose a residual convolutional RNN for real-time cardiac cine reconstruction. To the best of our knowledge, this is the first work applying deep learning approach to Cartesian real-time cardiac cine reconstruction. Based on the evaluation from radiol…
United Imaging Intelligence(联影智能);UIH America, Inc.(联影美国公司);United Imaging Healthcare(联影医疗)
Retrospectively gated cine (retro-cine) MRI is the clinical standard for cardiac functional analysis. Deep learning (DL) based methods have been proposed for the reconstruction of highly undersampled MRI data and show superior image quality and magnitude faster reconstruction time than CS-based methods. Nevertheless, it remains unclear whether DL reconstruction is suitable for cardiac function analysis. To address this question, in this study we evaluate and compare the cardiac functional values (EDV, ESV and EF for LV and RV, respectively) obtained from highly accelerated MRI acquisition usin…
Rensselaer Polytechnic Institute(伦斯勒理工学院);Cedars-Sinai Medical Center(西达赛奈医疗中心);University of California, Los Angeles(加州大学洛杉矶分校)
Cine cardiac magnetic resonance imaging (MRI) is widely used for diagnosis of cardiac diseases thanks to its ability to present cardiovascular features in excellent contrast. As compared to computed tomography (CT), MRI, however, requires a long scan time, which inevitably induces motion artifacts and causes patients' discomfort. Thus, there has been a strong clinical motivation to develop techniques to reduce both the scan time and motion artifacts. Given its successful applications in other medical imaging tasks such as MRI super-resolution and CT metal artifact reduction, deep learning is a…
Adhesions are an important cause of chronic pain following abdominal surgery. Recent developments in abdominal cine-MRI have enabled the non-invasive diagnosis of adhesions. Adhesions are identified on cine-MRI by the absence of sliding motion during movement. Diagnosis and mapping of adhesions improves the management of patients with pain. Detection of abdominal adhesions on cine-MRI is challenging from both a radiological and deep learning perspective. We focus on classifying presence or absence of adhesions in sagittal abdominal cine-MRI series. We experimented with spatio-temporal deep lea…
Contrast-Free Myocardial Scar Segmentation in Cine MRI using Motion and Texture Fusion
University of Oxford(牛津大学);University of Southampton(南安普顿大学);National University of Singapore(新加坡国立大学);Fudan University(复旦大学);Zhongshan Hospital, Fudan University(复旦大学附属中山医院)
Massachusetts General Hospital(麻省总医院);Harvard Medical School(哈佛医学院);National Taiwan University(台湾大学);University of Southern California(南加州大学)
Assessment of cardiovascular disease (CVD) with cine magnetic resonance imaging (MRI) has been used to non-invasively evaluate detailed cardiac structure and function. Accurate segmentation of cardiac structures from cine MRI is a crucial step for early diagnosis and prognosis of CVD, and has been greatly improved with convolutional neural networks (CNN). There, however, are a number of limitations identified in CNN models, such as limited interpretability and high complexity, thus limiting their use in clinical practice. In this work, to address the limitations, we propose a lightweight and i…
University of Notre Dame(圣母大学);Guangdong Cardiovascular Institute(广东省心血管病研究所);Guangdong Provincial People’s Hospital(广东省人民医院);Boston Children’s Hospital(波士顿儿童医院);Harvard Medical School(哈佛医学院);University of Pittsburgh(匹兹堡大学)
Real-time cardiac magnetic resonance imaging (MRI) plays an increasingly important role in guiding various cardiac interventions. In order to provide better visual assistance, the cine MRI frames need to be segmented on-the-fly to avoid noticeable visual lag. In addition, considering reliability and patient data privacy, the computation is preferably done on local hardware. State-of-the-art MRI segmentation methods mostly focus on accuracy only, and can hardly be adopted for real-time application or on local hardware. In this work, we present the first hardware-aware multi-scale neural archite…
Charité - Universitätsmedizin Berlin(柏林夏里特医学院);Berlin Institute of Health(柏林健康研究所);Physikalisch-Technische Bundesanstalt (PTB)(德国联邦物理技术研究院(PTB));King’s College London(伦敦国王学院)
In this work we reduce undersampling artefacts in two-dimensional ($2D$) golden-angle radial cine cardiac MRI by applying a modified version of the U-net. We train the network on $2D$ spatio-temporal slices which are previously extracted from the image sequences. We compare our approach to two $2D$ and a $3D$ Deep Learning-based post processing methods and to three iterative reconstruction methods for dynamic cardiac MRI. Our method outperforms the $2D$ spatially trained U-net and the $2D$ spatio-temporal U-net. Compared to the $3D$ spatio-temporal U-net, our method delivers comparable results…
Cine cardiac MRI reconstruction using a convolutional recurrent network with refinement
Institute for Digital Communications, University of Edinburgh(爱丁堡大学数字通信研究所);Institute of Information Science and Technologies “Alessandro Faedo”, National Research Council of Italy (CNR)(意大利国家研究委员会信息科学与技术研究所(亚历山德罗·法埃多));Department of Information Engineering, University of Pisa(比萨大学信息工程系);Institute for Infrastructure and Environment, University of Edinburgh(爱丁堡大学基础设施与环境研究所);The Alan Turing Institute(阿兰·图灵研究所)
Cardiac cine magnetic resonance imaging (MRI) can be considered the optimal criterion for measuring cardiac function. This imaging technique can provide us with detailed information about cardiac structure, tissue composition and even blood flow. This work considers the application of the higher order dynamic mode decomposition (HODMD) method to a set of MR images of a heart, with the ultimate goal of identifying the main patterns and frequencies driving the heart dynamics. A novel algorithm based on singular value decomposition combined with HODMD is introduced, providing a three-dimensional …
Personalized 4D Whole Heart Geometry Reconstruction from Cine MRI for Cardiac Digital Twins
Department of Biomedical Engineering, National University of Singapore, Singapore(新加坡国立大学生物医学工程系);School of Data Science, Fudan University, Shanghai, China(复旦大学数据科学学院);Department of Engineering Science, University of Oxford, Oxford, UK(牛津大学工程科学系);Department of Medicine, National University of Singapore, Singapore(新加坡国立大学医学系);Department of Cardiology, National University Heart Centre Singapore, Singapore(新加坡国立心脏中心心内科部)
University of Notre Dame(圣母大学);Guangdong Provincial People’s Hospital(广东省人民医院);IBM Thomas J. Watson Research Center(IBM托马斯·J·沃森研究中心)
Real-time cine magnetic resonance imaging (MRI) plays an increasingly important role in various cardiac interventions. In order to enable fast and accurate visual assistance, the temporal frames need to be segmented on-the-fly. However, state-of-the-art MRI segmentation methods are used either offline because of their high computation complexity, or in real-time but with significant accuracy loss and latency increase (causing visually noticeable lag). As such, they can hardly be adopted to assist visual guidance. In this work, inspired by a new interpretation of Independent Component Analysis …
Cine cardiac magnetic resonance (CMR) imaging is considered the gold standard for cardiac function evaluation. However, cine CMR acquisition is inherently slow and in recent decades considerable effort has been put into accelerating scan times without compromising image quality or the accuracy of derived results. In this paper, we present a fully-automated, quality-controlled integrated framework for reconstruction, segmentation and downstream analysis of undersampled cine CMR data. The framework enables active acquisition of radial k-space data, in which acquisition can be stopped as soon as …
School of Biomedical Engineering & Imaging Sciences, King’s College London, UK(伦敦国王学院生物医学工程与成像科学学院);Technical University of Munich, Germany(慕尼黑工业大学);Biomedical Image Analysis Group, Imperial College London, UK(帝国理工学院生物医学图像分析组);Department of Adult and Paediatric Cardiology, Guy’s and St Thomas’ NHS Foundation Trust, London, UK(盖伊和圣托马斯国民健康服务信托基金会成人及儿科心脏病科);Coimbra Institute for Biomedical Imaging and Translational Research, University of Coimbra, Portugal(科英布拉大学科英布拉生物医学成像与转化研究学院);Helmholtz Center Munich, Germany(慕尼黑亥姆霍兹中心)
Cine cardiac MRI is routinely acquired for the assessment of cardiac health, but the imaging process is slow and typically requires several breath-holds to acquire sufficient k-space profiles to ensure good image quality. Several undersampling-based reconstruction techniques have been proposed during the last decades to speed up cine cardiac MRI acquisition. However, the undersampling factor is commonly fixed to conservative values before acquisition to ensure diagnostic image quality, potentially leading to unnecessarily long scan times. In this paper, we propose an end-to-end quality-aware c…
University of Notre Dame(圣母大学);Guangdong Provincial People’s Hospital(广东省人民医院);Zhejiang University(浙江大学);University of New Mexico(新墨西哥大学)
Accurately segmenting temporal frames of cine magnetic resonance imaging (MRI) is a crucial step in various real-time MRI guided cardiac interventions. To achieve fast and accurate visual assistance, there are strict requirements on the maximum latency and minimum throughput of the segmentation framework. State-of-the-art neural networks on this task are mostly hand-crafted to satisfy these constraints while achieving high accuracy. On the other hand, while existing literature have demonstrated the power of neural architecture search (NAS) in automatically identifying the best neural architect…
Reconstruction of Cardiac Cine MRI Using Motion-Guided Deformable Alignment and Multi-Resolution Fusion
School of Health Science and Engineering, University of Shanghai for Science and Technology(上海理工大学健康科学与工程学院);ToolSensing Technologies Co., Ltd(拓深科技有限公司);School of Medical Instruments, Shanghai University of Medicine and Health Sciences(上海健康医学院医疗器械学院);Shanghai Key Laboratory of Multidimensional Information Processing, School of Communication & Electronic Engineering, East China Normal University(华东师范大学通信与电子工程学院多维信息处理上海重点实验室)
Respiratory motion can cause strong blurring artifacts in the reconstructed image during MR acquisition. These artifacts become more prominent when use in the presence of undersampled data. Recently, compressed sensing (CS) is developed as an MR reconstruction technique, to recover good quality images from the compressive k-space samples. To maximize the benefits of CS in free breathing data, it is understandable to use CS with the motion corrected images. In this paper, we have developed a new CS based motion corrected image reconstruction technique. In this two-stage technique, we use simila…
Personalized 3D Myocardial Infarct Geometry Reconstruction from Cine MRI with Explicit Cardiac Motion Modeling
Department of Biomedical Engineering, National University of Singapore, Singapore(新加坡国立大学生物医学工程系);Department of Computer Science, National University of Singapore, Singapore(新加坡国立大学计算机科学系);Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand(奥克兰大学生物工程研究所);School of Biomedical Engineering and Imaging Sciences, King’s College London, UK(伦敦国王学院生物医学工程与成像科学学校);Department of Medicine, National University of Singapore, Singapore(新加坡国立大学医学系);Department of Cardiology, National University Heart Centre Singapore, Singapore(新加坡国立心脏中心心血管科)
University of Kansas(堪萨斯大学);Rochester Institute of Technology(罗切斯特理工学院)
Patient-specific left ventricle (LV) myocardial models have the potential to be used in a variety of clinical scenarios for improved diagnosis and treatment plans. Cine cardiac magnetic resonance (MR) imaging provides high resolution images to reconstruct patient-specific geometric models of the LV myocardium. With the advent of deep learning, accurate segmentation of cardiac chambers from cine cardiac MR images and unsupervised learning for image registration for cardiac motion estimation on a large number of image datasets is attainable. Here, we propose a deep leaning-based framework for th…
Massachusetts General Hospital(麻省总医院);Harvard Medical School(哈佛医学院);University of Southern California(南加州大学)
Cardiac cine magnetic resonance imaging (MRI) has been used to characterize cardiovascular diseases (CVD), often providing a noninvasive phenotyping tool.~While recently flourished deep learning based approaches using cine MRI yield accurate characterization results, the performance is often degraded by small training samples. In addition, many deep learning models are deemed a ``black box," for which models remain largely elusive in how models yield a prediction and how reliable they are. To alleviate this, this work proposes a lightweight successive subspace learning (SSL) framework for CVD …
Massachusetts General Hospital(麻省总医院);Harvard Medical School(哈佛医学院);Johns Hopkins University(约翰斯·霍普金斯大学);University of Maryland School of Dentistry(马里兰大学牙科学院)
Tagged magnetic resonance imaging (MRI) is a widely used imaging technique for measuring tissue deformation in moving organs. Due to tagged MRI's intrinsic low anatomical resolution, another matching set of cine MRI with higher resolution is sometimes acquired in the same scanning session to facilitate tissue segmentation, thus adding extra time and cost. To mitigate this, in this work, we propose a novel dual-cycle constrained bijective VAE-GAN approach to carry out tagged-to-cine MR image synthesis. Our method is based on a variational autoencoder backbone with cycle reconstruction constrain…
Massachusetts General Hospital(麻省总医院);Harvard Medical School(哈佛医学院);Johns Hopkins University(约翰斯·霍普金斯大学);University of Maryland School of Dentistry(马里兰大学牙医学院)
Cycle reconstruction regularized adversarial training -- e.g., CycleGAN, DiscoGAN, and DualGAN -- has been widely used for image style transfer with unpaired training data. Several recent works, however, have shown that local distortions are frequent, and structural consistency cannot be guaranteed. Targeting this issue, prior works usually relied on additional segmentation or consistent feature extraction steps that are task-specific. To counter this, this work aims to learn a general add-on structural feature extractor, by explicitly enforcing the structural alignment between an input and it…
Subspace Implicit Neural Representations for Real-Time Cardiac Cine MR Imaging
Technical University of Munich(慕尼黑工业大学);Helmholtz Munich(亥姆霍兹慕尼黑中心);University of Tübingen(蒂宾根大学);University of Michigan(密歇根大学);Pontificia Universidad Católica de Chile(智利天主教大学);King’s College London(伦敦国王学院);Imperial College London(帝国理工学院)
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, characterised by a rapid and irregular electrical activation of the atria. Treatments for AF are often ineffective and few atrial biomarkers exist to automatically characterise atrial function and aid in treatment selection for AF. Clinical metrics of left atrial (LA) function, such as ejection fraction (EF) and active atrial contraction ejection fraction (aEF), are promising, but have until now typically relied on volume estimations extrapolated from single-slice images. In this work, we study volumetric functional biom…
In this work, we implement a fully convolutional segmenter featuring both a learned group structure and a regularized weight-pruner to reduce the high computational cost in volumetric image segmentation. We validated our framework on the ACDC dataset featuring one healthy and four pathology groups imaged throughout the cardiac cycle. Our technique achieved Dice scores of 96.8% (LV blood-pool), 93.3% (RV blood-pool) and 90.0% (LV Myocardium) with five-fold cross-validation and yielded similar clinical parameters as those estimated from the ground truth segmentation data. Based on these results,…
Deep learning-based image reconstruction methods have achieved promising results across multiple MRI applications. However, most approaches require large-scale fully-sampled ground truth data for supervised training. Acquiring fully-sampled data is often either difficult or impossible, particularly for dynamic contrast enhancement (DCE), 3D cardiac cine, and 4D flow. We present a deep learning framework for MRI reconstruction without any fully-sampled data using generative adversarial networks. We test the proposed method in two scenarios: retrospectively undersampled fast spin echo knee exams…
University of Virginia(弗吉尼亚大学);University of Virginia Health System(弗吉尼亚大学卫生系统)
The selection of an optimal pacing site, which is ideally scar-free and late activated, is critical to the response of cardiac resynchronization therapy (CRT). Despite the success of current approaches formulating the detection of such late mechanical activation (LMA) regions as a problem of activation time regression, their accuracy remains unsatisfactory, particularly in cases where myocardial scar exists. To address this issue, this paper introduces a multi-task deep learning framework that simultaneously estimates LMA amount and classify the scar-free LMA regions based on cine displacement…
Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences(中国科学院深圳先进技术研究院保罗·C·劳特伯生物医学成像研究中心);Research Center for Medical AI, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences(中国科学院深圳先进技术研究院医学人工智能研究中心);Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences(中国科学院大学深圳先进技术学院);The State University of New York, Buffalo(纽约州立大学布法罗分校)
Deep learning has achieved good success in cardiac magnetic resonance imaging (MRI) reconstruction, in which convolutional neural networks (CNNs) learn a mapping from the undersampled k-space to the fully sampled images. Although these deep learning methods can improve the reconstruction quality compared with iterative methods without requiring complex parameter selection or lengthy reconstruction time, the following issues still need to be addressed: 1) all these methods are based on big data and require a large amount of fully sampled MRI data, which is always difficult to obtain for cardiac…
Imperial College London(帝国理工学院);Technical University Munich(慕尼黑工业大学);University of Edinburgh(爱丁堡大学);MRC London Institute of Medical Sciences(MRC伦敦医学科学研究所)
Recovering the 3D motion of the heart from cine cardiac magnetic resonance (CMR) imaging enables the assessment of regional myocardial function and is important for understanding and analyzing cardiovascular disease. However, 3D cardiac motion estimation is challenging because the acquired cine CMR images are usually 2D slices which limit the accurate estimation of through-plane motion. To address this problem, we propose a novel multi-view motion estimation network (MulViMotion), which integrates 2D cine CMR images acquired in short-axis and long-axis planes to learn a consistent 3D motion fi…
We propose a deep self-learning algorithm to learn the manifold structure of free-breathing and ungated cardiac data and to recover the cardiac CINE MRI from highly undersampled measurements. Our method learns the manifold structure in the dynamic data from navigators using autoencoder network. The trained autoencoder is then used as a prior in the image reconstruction framework. We have tested the proposed method on free-breathing and ungated cardiac CINE data, which is acquired using a navigated golden-angle gradient-echo radial sequence. Results show the ability of our method to better capt…
Gabor Primitives for Accelerated Cardiac Cine MRI Reconstruction
Chair for AI in Healthcare and Medicine, Technical University of Munich (TUM) and TUM University Hospital, Munich, Germany(人工智能在医疗与医学中的chair,慕尼黑技术大学(TUM)和慕尼黑技术大学医院,德国慕尼黑);School of Computation and Information Technology, Technical University of Munich, Munich, Germany(计算与信息科技学院,慕尼黑技术大学,德国慕尼黑);Institute of Machine Learning in Biomedical Imaging, Helmholtz Munich, Neuherberg, Germany(生物医学影像中的机器学习研究所,海德堡慕尼黑,德国纽赫堡);Department of Radiology, Boston Children's Hospital and Harvard Medical School, Boston, USA(放射科,波士顿儿童医院和哈佛医学院,美国波士顿);Munich Center for Machine Learning, Technical University of Munich, Munich, Germany(慕尼黑机器学习中心,慕尼黑技术大学,德国慕尼黑);GE HealthCare, Munich, Germany(通用电气医疗系统,德国慕尼黑);School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom(生物医学工程与成像科学学院,伦敦国王学院,英国伦敦);Department of Computing, Imperial College London, London, United Kingdom(计算学院,伦敦帝国学院,英国伦敦)
本文提出 Gabor 原始要素用于加速心脏 cine MRI 重建,通过调制高斯包络实现灵活频谱支持,提升对光滑结构和锐利边界的表示能力。
Unsupervised Adversarial Domain Adaptation for Uterine layer Segmentation: From Labeled Cine to Unlabeled Dynamic EPI MRI
Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg(埃尔朗根-纽伦堡大学弗里德里希-亚历山大分校埃尔朗根大学医院放射学研究所);CAIMED(CAIMED机构);L3S(L3S机构);Institut für Informationsverarbeitung, Leibniz University Hannover(汉诺威莱布尼茨大学信息处理研究所)
DINOMotion: advanced robust tissue motion tracking with DINOv2 in 2D-Cine MRI-guided radiotherapy
Department of Computer Science and Software Engineering, Concordia University(计算机科学与软件工程系,康科迪亚大学);Department of Electrical and Computer Engineering, Concordia University(电气与计算机工程系,康科迪亚大学);Elekta Ltd.(Elekta公司);Diagnos Medical Systems(Diagnos医疗系统)
GSMorph: Gradient Surgery for cine-MRI Cardiac Deformable Registration
University of Leeds(利兹大学);Radboud University Medical Centre(拉德堡德大学医学中心);Netherlands Cancer Institute(荷兰癌症研究所);Shenzhen University(深圳大学);Shenzhen RayShape Medical Technology Co., Ltd(深圳睿心医疗科技有限公司)
University of California, Los Angeles(加州大学洛杉矶分校);University of Alberta(阿尔伯塔大学);Mazankowski Alberta Heart Institute(马赞科夫斯基阿尔伯塔心脏研究所)
This study proposes a fully automated approach for the left atrial segmentation from routine cine long-axis cardiac magnetic resonance image sequences using deep convolutional neural networks and Bayesian filtering. The proposed approach consists of a classification network that automatically detects the type of long-axis sequence and three different convolutional neural network models followed by unscented Kalman filtering (UKF) that delineates the left atrium. Instead of training and predicting all long-axis sequence types together, the proposed approach first identifies the image sequence t…
Arizona State University(亚利桑那州立大学);Barrow Neurological Institute(巴罗神经学研究所);Mayo Clinic Arizona(亚利桑那州梅奥诊所)
Typical Magnetic Resonance Imaging (MRI) scan may take 20 to 60 minutes. Reducing MRI scan time is beneficial for both patient experience and cost considerations. Accelerated MRI scan may be achieved by acquiring less amount of k-space data (down-sampling in the k-space). However, this leads to lower resolution and aliasing artifacts for the reconstructed images. There are many existing approaches for attempting to reconstruct high-quality images from down-sampled k-space data, with varying complexity and performance. In recent years, deep-learning approaches have been proposed for this task, …
Physikalisch-Technische Bundesanstalt (PTB)(德国联邦物理技术研究院);University of Innsbruck(因斯布鲁克大学);King’s College London(伦敦国王学院);Technical University of Berlin(柏林工业大学)
Purpose: Iterative Convolutional Neural Networks (CNNs) which resemble unrolled learned iterative schemes have shown to consistently deliver state-of-the-art results for image reconstruction problems across different imaging modalities. However, because these methodes include the forward model in the architecture, their applicability is often restricted to either relatively small reconstruction problems or to problems with operators which are computationally cheap to compute. As a consequence, they have so far not been applied to dynamic non-Cartesian multi-coil reconstruction problems. Method…
Real-time cardiac cine MRI -- A comparison of a diffusion probabilistic model with alternative state-of-the-art image reconstruction techniques for undersampled spiral acquisitions
Facebook AI Research(Facebook人工智能研究);fastMRI team(fastMRI团队)
Deep learning approaches to accelerated MRI take a matrix of sampled Fourier-space lines as input and produce a spatial image as output. In this work we show that by careful choice of the offset used in the sampling procedure, the symmetries in k-space can be better exploited, producing higher quality reconstructions than given by standard equally-spaced samples or randomized samples motivated by compressed sensing.
Attention Incorporated Network for Sharing Low-rank, Image and K-space Information during MR Image Reconstruction to Achieve Single Breath-hold Cardiac Cine Imaging
University of Tuebingen(蒂宾根大学);Technical University of Munich(慕尼黑工业大学);Imperial College London(伦敦帝国学院);Stanford University(斯坦福大学);Klinikum Rechts der Isar, Technical University of Munich(慕尼黑工业大学右岸医院)