Motion Corrected Reconstruction for 3D Cardiac Simultaneous PET-MR Imaging: Towards Efficient Assessment of Coronary Artery Disease
Lead Research Organisation:
King's College London
Department Name: Imaging & Biomedical Engineering
Abstract
Coronary artery disease (CAD) is the leading single cause of morbidity and mortality in the Western world. CAD reduces the blood supply to the cardiac muscle and can lead to chest pain (angina) or heart attack. CAD diagnosis is currently performed by a wide range of invasive and non-invasive tests. However in current practice a non-negligible number of patients that may not need the intervention are referred to invasive, ionizing, and potentially harmful x-ray cardiac catheterization procedures. Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET) are two very promising non-invasive imaging technologies for early risk assessment, guidance of therapy and treatment monitoring of CAD. Both technologies provide complementary information, thus the recent introduction of simultaneous PET-MR systems offers great potential for accurate interpretation of findings of PET and MR images and new perspectives for better CAD diagnosis and treatment. For example three-dimensional fusion of PET perfusion images with non-invasive coronary MR images may allow the exact localization of stenosis, causing ischemia, to guide required interventions. However, inevitable patient motion (such as that caused by breathing and heart beating) during the acquisition degrades the image quality of both PET and MR images. Currently, commercial simultaneous PET-MR scanners do not feature technology for efficient and accurate correction of such motion.
Current research developments that deal with the motion problem in cardiovascular PET-MR concentrate mainly on improving the quality of PET images based on MR information. Moreover these approaches do not allow truly simultaneous PET and MR acquisitions leading to prolonged scan times, since diagnostic MR images need to be acquired after the simultaneous PET-MR acquisition. The reason is that dedicated MR acquisitions need to be performed concurrently with the PET imaging in order to correct for motion in the PET data. This means that MR is being used as an expensive motion-correction device limiting its diagnostic utility. In this proposal we aim to develop, implement and test the clinical feasibility of an efficient PET-MR acquisition and reconstruction framework that enables truly simultaneous acquisition of complementary PET and MR diagnostic information. We hypothesize that this can be achieved using synergistic information of both modalities i.e. functional, anatomic and motion MR information, and quantitative perfusion PET data in a motion corrected reconstruction approach. The proposed approach is foreseen as an important step towards clinical adoption of PET-MR cardiovascular imaging and lastly towards an efficient and accurate non-invasive assessment of CAD.
Current research developments that deal with the motion problem in cardiovascular PET-MR concentrate mainly on improving the quality of PET images based on MR information. Moreover these approaches do not allow truly simultaneous PET and MR acquisitions leading to prolonged scan times, since diagnostic MR images need to be acquired after the simultaneous PET-MR acquisition. The reason is that dedicated MR acquisitions need to be performed concurrently with the PET imaging in order to correct for motion in the PET data. This means that MR is being used as an expensive motion-correction device limiting its diagnostic utility. In this proposal we aim to develop, implement and test the clinical feasibility of an efficient PET-MR acquisition and reconstruction framework that enables truly simultaneous acquisition of complementary PET and MR diagnostic information. We hypothesize that this can be achieved using synergistic information of both modalities i.e. functional, anatomic and motion MR information, and quantitative perfusion PET data in a motion corrected reconstruction approach. The proposed approach is foreseen as an important step towards clinical adoption of PET-MR cardiovascular imaging and lastly towards an efficient and accurate non-invasive assessment of CAD.
Planned Impact
The beneficiaries of this research will be patients with suspected or known coronary artery disease, who will benefit from efficient and accurate non-invasive diagnostic tests. Secondary beneficiaries will be clinicians involved in the diagnosis and treatment of CAD. Complementary information provided by both imaging technologies will enable more reliable diagnosis. In the long term this project will also help reducing NHS healthcare costs by a) reducing the number of examinations: both PET and MR images will be acquired in a single-test, in a shorter scan time (from 60 min each scan to ~30 min for the simultaneous PET-MR) and will require one integrated reporting from the clinicians; and b) improving hospital discharge rates by providing more accurate diagnosis. Moreover the technology developed in this project may also have an impact in PET-MR cancer imaging where respiratory motion is a known major challenge. Through commercialisation, the research will be of benefit to the imaging manufacturers and subsequently to the healthcare system by improving patient management through improved treatment outcome and reduced healthcare costs on a national and international level.
Our goal is to maximise the impact of our work through dissemination of our ideas and results to the academic and clinical communities and potential industrial partners. The scientific methodology results from this research will be output as research publications in high-impact journals in the field of medical imaging. A large amount of phantom and in-vivo PET-MR data will be generated during the lifetime of the grant. After the studies are published in scientific journals, and after they are patented if patenting is a viable option, this data will be made publicly available for research use. We also plan to use the data to organise a "Motion Correction Challenger" in relevant Scientific Conferences. Moreover the data and reconstruction codes generated during the lifetime of the grant will be used in different teaching, networking and software development activities planned within the EP/M022587/1 "Computational Collaborative Project in Synergistic PET-MR Reconstruction" grant. Dr. Prieto (PI of this proposal) and Dr. Reader (CoI of this proposal) are both CoIs in this recently awarded Computational Collaborative Project PET-MR grant.
Clinical simultaneous PET-MR systems have been available for only a few years with two installations in the UK, one of them at the Division of Imaging Sciences at KCL. However, the UK government is expected to announce funding for five new PET-MR systems. Current commercial PET-MR scanners do not feature advanced techniques to deal with the problem of motion in cardiovascular imaging, therefore this project is foreseen as an important step towards clinical translation and validation of cardiovascular PET-MR. At the completion of this project we plan to work closely together with industrial partner to transfer the developed methodology into the product software to allow wide spread clinical use of this research.
Our goal is to maximise the impact of our work through dissemination of our ideas and results to the academic and clinical communities and potential industrial partners. The scientific methodology results from this research will be output as research publications in high-impact journals in the field of medical imaging. A large amount of phantom and in-vivo PET-MR data will be generated during the lifetime of the grant. After the studies are published in scientific journals, and after they are patented if patenting is a viable option, this data will be made publicly available for research use. We also plan to use the data to organise a "Motion Correction Challenger" in relevant Scientific Conferences. Moreover the data and reconstruction codes generated during the lifetime of the grant will be used in different teaching, networking and software development activities planned within the EP/M022587/1 "Computational Collaborative Project in Synergistic PET-MR Reconstruction" grant. Dr. Prieto (PI of this proposal) and Dr. Reader (CoI of this proposal) are both CoIs in this recently awarded Computational Collaborative Project PET-MR grant.
Clinical simultaneous PET-MR systems have been available for only a few years with two installations in the UK, one of them at the Division of Imaging Sciences at KCL. However, the UK government is expected to announce funding for five new PET-MR systems. Current commercial PET-MR scanners do not feature advanced techniques to deal with the problem of motion in cardiovascular imaging, therefore this project is foreseen as an important step towards clinical translation and validation of cardiovascular PET-MR. At the completion of this project we plan to work closely together with industrial partner to transfer the developed methodology into the product software to allow wide spread clinical use of this research.
Publications
Mehranian A
(2017)
PET image reconstruction using multi-parametric anato-functional priors
in Physics in Medicine & Biology
Cruz G
(2017)
Highly efficient nonrigid motion-corrected 3D whole-heart coronary vessel wall imaging.
in Magnetic resonance in medicine
Chiribiri A
(2016)
Imaging of the Cardiovascular System, Thorax, and Abdomen
Munoz C
(2016)
MR-Based Cardiac and Respiratory Motion-Compensation Techniques for PET-MR Imaging
in PET Clinics
Description | Coronary artery disease (CAD) is the leading single cause of morbidity and mortality in the Western world. CAD reduces the blood supply to the cardiac muscle and can lead to chest pain (angina) or heart attack CAD diagnosis is currently performed by a wide range of invasive and non-invasive tests. However in current practice a non-negligible number of patients that may not need the intervention are referred to invasive, ionizing, and potentially harmful x-ray cardiac catheterization procedures. Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET) are two very promising non-invasive imaging technologies for early risk assessment, guidance of therapy and treatment monitoring of CAD. Both technologies provide complementary information, thus the recent introduction of simultaneous PET-MR systems offers great potential for accurate interpretation of findings of PET and MR images and new perspectives for better CAD diagnosis and treatment. However, inevitable patient motion (such as that caused by breathing and heart beating) during the acquisition degrades the image quality of both PET and MR images. Through the research funded on this grant we have developed a new framework that allows to correct for respiratory motion in both PET and MR images, enabling better quality PET images, faster MR acquisitions and full co-registration between both datasets to facilitate fusion of the images. We have tested the feasibility of the proposed approach in a small cohort of oncology patients and have a establish collaborations with: 1) the Department of Nuclear Medicine in the Technical University of Munich, 2) the University of Edinburgh and 3) the Department of Nuclear Medicine and Radiology of the University of Maastrich to test the feasibility of the method in a small cohort of patients with cardiovascular disease. In a parallel study we have developed a novel MR sequence that allows simultaneous acquisition of bright blood and black blood whole heart images to enable visualisation of coronary lumen and coronary thrombus/hemorrhage. The acquisition is efficient as correct for respiratory motion and provides fully co-registered datasets to facilitate analysis. This sequence is currently being tested in a small cohort of patients with Cardiovascular disease at St Thomas' Hospital. |
Exploitation Route | We are currently working in close collaboration with Siemens to generate a work-in-progress version of the framework which can be distributed to collaborators in other sites to evaluate the performance of the method. The work-in-progress package is ready and has been distributed to collaborators for MR scanners only, a version for hybrid PET-MR scanners is currently under development. |
Sectors | Healthcare |
URL | https://kclcvmimaging.wordpress.com/ |
Description | Through the research funded on this grant we have developed a new framework that allows to correct for respiratory motion in both PET and MR cardiac images, enabling better quality PET images, faster MR acquisitions and full co-registration between both datasets to facilitate fusion of the images. We have tested the feasibility of the proposed approach in a small cohort of oncology patients and have a establish collaborations with: 1) the Department of Nuclear Medicine in the Technical University of Munich, 2) the University of Edinburgh and 3) the Department of Nuclear Medicine and Radiology of the University of Maastrich to test the feasibility of the method in other cohorts of with cardiovascular disease. Collaborations are still ongoing. As a continuation of this grant we are currently testing the proposed framework in a pilot study for cardiac sarcoidosis patients, considering quantification of inflammation with simultaneous MR and PET images. We have further improved the PET reconstruction considering motion corrected and MR-guided reconstruction. We have also extended the proposed approach to enable quantitative T2 mapping, which was evaluated in small cohort of patients with cardiac sarcoidosis. |
First Year Of Impact | 2022 |
Sector | Healthcare |
Impact Types | Societal |
Description | 2018 IEEE NSS-MIC Trainee Grant |
Amount | $655 (AUD) |
Organisation | Institute of Electrical and Electronics Engineers (IEEE) |
Sector | Learned Society |
Country | United States |
Start | 11/2018 |
End | 11/2018 |
Description | ISMRM Educational Stipend 2017 |
Amount | $900 (USD) |
Organisation | International Society for Magnetic Resonance in Medicine (ISMRM) |
Sector | Charity/Non Profit |
Country | United States |
Start | 03/2017 |
End | 04/2017 |
Description | ISMRM Educational Stipend 2018 |
Amount | $1,815 (USD) |
Organisation | International Society for Magnetic Resonance in Medicine (ISMRM) |
Sector | Charity/Non Profit |
Country | United States |
Start | 05/2018 |
End | 06/2018 |
Description | NIHR Pump-Prime |
Amount | £66,757 (GBP) |
Organisation | National Institute for Health Research |
Sector | Public |
Country | United Kingdom |
Start | 03/2020 |
End | 11/2020 |
Description | SCMR 2019 Travel Award (3 people) |
Amount | € 1,500 (EUR) |
Organisation | Society for Cardiovascular Magnetic Resonance (SCMR) |
Sector | Charity/Non Profit |
Country | United States |
Start | 02/2019 |
End | 02/2019 |
Description | SMRA 2018 |
Amount | $550 (USD) |
Organisation | Society for Magnetic Resonance Angiography (SMRA) |
Sector | Learned Society |
Country | Canada |
Start | 07/2018 |
End | 08/2018 |
Title | BOOST Magnetic Resonance Imaging Sequence |
Description | We have developed an acquisition and reconstruction framework that simultaneously generated 3D whole-heart bright- and black-blood Magnetic Resonance images of the heart. This framework can be applied to a broad range of cardiac pathologies and is being currently clinically validated locally. The package will be distributed to other academic institution and broader clinical validation is foresee. |
Type Of Material | Improvements to research infrastructure |
Year Produced | 2017 |
Provided To Others? | Yes |
Impact | This framework can be applied to a broad range of cardiac pathologies and is being currently clinically validated locally. The package will be distributed to other academic institution and broader clinical validation is foresee. |
Title | Motion Corrected PET-CMRA |
Description | We have developed a motion corrected PET-CMRA (Positron Emission Tomography-Coronary Magnetic Resonance Angiography) framework that correct for respiratory motion in simultaneously acquired PET and MR images of the heart. This framework can be applied to a broad range of cardiac pathologies and is being currently clinically validated locally and with 3 external collaborators. The package will be distributed to other academic institution and broader clinical validation is foresee. |
Type Of Material | Improvements to research infrastructure |
Year Produced | 2017 |
Provided To Others? | Yes |
Impact | This framework can be applied to a broad range of cardiac pathologies and is being currently clinically validated locally and with 3 external collaborators. The package will be distributed to other academic institution and broader clinical validation is foresee. |
Description | Imperial College London CMRA |
Organisation | Imperial College London |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Established a collaborative project with Imperial College London to clinically validate a new coronary cardiac MR sequence that includes our under sampled and motion compensated reconstruction developments with intravascular optical coherence tomography in patients with acute coronary syndrome for the simultaneous non-contrast free breathing 3D high resolution magnetic resonance coronary artery angiography and high-risk plaque imaging. Ethical approval for the project has been obtained, an NIHR Pump-Prime award worth (£66,757.50) has been competitively secured and a British Heart Foundation Clinical Research Fellowship grant application has been submitted (currently under assessment). |
Collaborator Contribution | Access to facilities and patients. |
Impact | NIHR Pump-Prime award worth (£66,757.50) has been competitively secured and a British Heart Foundation Clinical Research Fellowship grant application has been submitted (currently under assessment). |
Start Year | 2019 |
Description | Maastricht University Medical Center Cardiac PET-MR |
Organisation | Maastricht University Medical Center+ |
Country | Netherlands |
Sector | Academic/University |
PI Contribution | We have developed a framework for efficient free-breathing simultaneous whole-heart coronary magnetic resonance angiography (CMRA) and cardiac positron emission tomography (PET) on a 3T PET-MR system. The acquisition and reconstruction methods are implemented inline in the scanner software. Validation of the proposed framework in patients with cardiovascular disease is being performed in collaboration with Dr. Eline Kooi at the Maastricht University Medical Center . |
Collaborator Contribution | Dr Eline Kooi and Dr Rik Moonen will be acquiring clinical data to validate the proposed framework. |
Impact | No outcomes yet. The collaboration involves Physicists experts in Magnetic Resonance Imaging and Nuclear Medicine and clinicians, both cardiologists and radiologists. |
Start Year | 2017 |
Description | TUM (Technische Universität München) Cardiac PET-MR |
Organisation | Technical University of Munich |
Department | Department of Nuclear Medicine |
Country | Germany |
Sector | Academic/University |
PI Contribution | We have developed a framework for efficient free-breathing simultaneous whole-heart coronary magnetic resonance angiography (CMRA) and cardiac positron emission tomography (PET) on a 3T PET-MR system. The acquisition and reconstruction methods are implemented inline in the scanner software. Validation of the proposed framework in patients with cardiovascular disease is being performed in collaboration with Dr. Stephan Nekolla Head of Multimodal Cardiac Imaging at the Department of Nuclear Medicine in Munich. |
Collaborator Contribution | Karl Kunze, PhD student from TUM Munich, spent two weeks at KCL to learn how to use the framework and acquire the data. Currently he is acquiring data on patients in TUM. |
Impact | The collaboration involves Physicists experts in Magnetic Resonance Imaging and Nuclear Medicine and clinicians, both cardiologists and radiologists. From this collaboration two abstracts were accepted for the international conference ISMRM in 2017. The journal article "Motion-corrected whole-heart PET-MR for the simultaneous visualisation of coronary artery integrity and myocardial viability: an initial clinical validation" is currently under revision in EJNMMI. |
Start Year | 2016 |
Description | University of Edinburgh Cardiac PET-MR |
Organisation | University of Edinburgh |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | We have developed a framework for efficient free-breathing simultaneous whole-heart coronary magnetic resonance angiography (CMRA) and cardiac positron emission tomography (PET) on a 3T PET-MR system. The acquisition and reconstruction methods are implemented inline in the scanner software. Validation of the proposed framework in patients with cardiovascular disease is being performed in collaboration with Dr Mark Dweck and Dr Scott Semple at the University of Edinburgh. |
Collaborator Contribution | Dr Mark Dweck and Dr Scott Semple will be acquiring clinical data to validate the proposed framework. |
Impact | No outcomes yet. The collaboration is multidisciplinary as involves Physicists experts in Magnetic Resonance Imaging and Nuclear Medicine and clinicians, both cardiologists and radiologists. |
Start Year | 2017 |
Title | METHOD AND APPARATUS FOR RECONSTRUCTING MAGNETIC RESONANCE IMAGE DATA |
Description | In a method for reconstructing magnetic resonance (MR) image data from k-space data, k-space data of an image region of a subject are provided to a computer that is also provided with multiple navigator signals for the image region of the subject. The computer sorts the k-space data into multiple bins, the multiple bins representing different motion states of the subject. For each of the multiple bins, the computer executes a compressed sensing procedure to reconstruct the MR image data from the k-space data in the respective bin. Execution of the compressed sensing procedure includes solving an optimization problem comprising a data consistency component and a transform sparsity component. Motion information is incorporated by the computer into at least one of the data consistency component and the transform sparsity component of the optimization problem. |
IP Reference | US2019317172 |
Protection | Patent application published |
Year Protection Granted | 2019 |
Licensed | No |
Impact | Pre-product software for Siemens MRI scanners |
Title | METHOD OF PERFORMING MAGNETIC RESONANCE IMAGING AND A MAGNETIC RESONANCE APPARATUS |
Description | In a method of performing magnetic resonance (MR) imaging, an MR apparatus, and a computer-readable medium during a first cardiac cycle of a subject, a first imaging sequence is generated for application to a subject. The first imaging sequence has a preparatory pulse and an inversion recovery pulse following the preparatory pulse. First signals emitted from the subject in response to the first imaging sequence are detected, and first image data are generated based on the first signals. During a second cardiac cycle following the first cardiac cycle, a second imaging sequence is generated for application to the subject. The second imaging sequence has a preparatory pulse. Second signals emitted from the subject in response to the second imaging sequence are detected, and second image data are generated based on the second signals. |
IP Reference | US2019064299 |
Protection | Patent application published |
Year Protection Granted | 2019 |
Licensed | No |
Impact | 20190064299 |
Description | Royal Society Summer Science Exhibition 2017 |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | From July 4th until the 9th the Royal Society held a Summer Science Festival where the School of Biomedical Engineering and Imaging Sciences from King's College London has a stand. The Royal Society was founded in 1690 and has been actively involved in promoting, encouraging and engaging science development. During the Summer Festival, different universities and companies showed some of the work that they have been involved and were trying to raise awareness for important issues e.g. global warming, how technology can be used to prevent and treat diseases, how to create energy from solar power, among others. This year, more than 14,000 people visited! Together with many other colleagues from the School our group (Dr Teresa Correia, Camila Munoz, Giovanna Nordio, Isabel Ramos and Dr Arna van Engelen), has been helping in engaging the public to the "Heart in your Hands" project. The objective of this project was to answer the question "How do we better engage the public about engineering research in the heart?". A multidisciplinary team was involved in answering it. The School of Biomedical Engineering and Imaging Sciences at KCL holds a multidisciplinary environment where scientists, doctors, physicist, computer programmers and engineers work together trying to understand how the heart works. They produce mathematical and computer models which replicates the heart and by using 3D printing technology they can develop physical heart models. These models can be used for different purposes: they can be used to help diagnosing a disease, to customize and plan a patient-orientated surgery, or to use these models as a show-case. In this Summer Festival the hands-on exhibition had three stands: (1) the heart viewer, where a range of different 3D printed hearts were available with the possibility to see how magnetic resonance imaging can be used to understand their unique function; (2) CardioSync, with a 3D printed heart controller to drive computational simulations of heart function and learn how to put a pacemaker in its correct place and (3) Hold a soft robotic heart in your hands that beats in time with your own heart, and discover its surprising biomechanical function. |
Year(s) Of Engagement Activity | 2017 |
Description | Symposium of Slovene researchers abroad |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Undergraduate students |
Results and Impact | PhD student Alina Schneider presented at the 6th symposium of Slovene researchers abroad on the 20th of December 2020 participating in a panel about imagining, introducing PET/MR imaging to approx. 40 students in Slovenia. (https://www.drustvovtis.si/si/koledar/simpozij2021) |
Year(s) Of Engagement Activity | 2020 |
URL | https://www.drustvovtis.si/si/koledar/simpozij2021 |