1
|
Niendorf T, Beenakker JWM, Langner S, Erb-Eigner K, Bach Cuadra M, Beller E, Millward JM, Niendorf TM, Stachs O. Ophthalmic Magnetic Resonance Imaging: Where Are We (Heading To)? Curr Eye Res 2021; 46:1251-1270. [PMID: 33535828 DOI: 10.1080/02713683.2021.1874021] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Magnetic resonance imaging of the eye and orbit (MReye) is a cross-domain research field, combining (bio)physics, (bio)engineering, physiology, data sciences and ophthalmology. A growing number of reports document technical innovations of MReye and promote their application in preclinical research and clinical science. Realizing the progress and promises, this review outlines current trends in MReye. Examples of MReye strategies and their clinical relevance are demonstrated. Frontier applications in ocular oncology, refractive surgery, ocular muscle disorders and orbital inflammation are presented and their implications for explorations into ophthalmic diseases are provided. Substantial progress in anatomically detailed, high-spatial resolution MReye of the eye, orbit and optic nerve is demonstrated. Recent developments in MReye of ocular tumors are explored, and its value for personalized eye models derived from machine learning in the treatment planning of uveal melanoma and evaluation of retinoblastoma is highlighted. The potential of MReye for monitoring drug distribution and for improving treatment management and the assessment of individual responses is discussed. To open a window into the eye and into (patho)physiological processes that in the past have been largely inaccessible, advances in MReye at ultrahigh magnetic field strengths are discussed. A concluding section ventures a glance beyond the horizon and explores future directions of MReye across multiple scales, including in vivo electrolyte mapping of sodium and other nuclei. This review underscores the need for the (bio)medical imaging and ophthalmic communities to expand efforts to find solutions to the remaining unsolved problems and technical obstacles of MReye, with the objective to transfer methodological advancements driven by MR physics into genuine clinical value.
Collapse
Affiliation(s)
- Thoralf Niendorf
- MRI.TOOLS GmbH, Berlin, Germany.,Berlin Ultrahigh Field Facility, Max Delbrueck Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Jan-Willem M Beenakker
- Department of Ophthalmology and Department of Radiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Sönke Langner
- Institute of Diagnostic and Interventional Radiology, Pediatric Radiology and Neuroradiology, Rostock University Medical Center, Rostock, Germany
| | - Katharina Erb-Eigner
- Department of Radiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Meritxell Bach Cuadra
- Center for Biomedical Imaging (CIBM), Lausanne, Switzerland.,Department of Radiology, Lausanne University and University Hospital, Lausanne, Switzerland
| | - Ebba Beller
- Institute of Diagnostic and Interventional Radiology, Pediatric Radiology and Neuroradiology, Rostock University Medical Center, Rostock, Germany
| | - Jason M Millward
- Berlin Ultrahigh Field Facility, Max Delbrueck Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | | | - Oliver Stachs
- Department Life, Light & Matter, University Rostock, Rostock, Germany.,Department of Ophthalmology, Rostock University Medical Center, Rostock, Germany
| |
Collapse
|
2
|
Naresh NK, Misener S, Zhang Z, Yang C, Ruh A, Bertolino N, Epstein FH, Collins JD, Markl M, Procissi D, Carr JC, Allen BA. Cardiac MRI Myocardial Functional and Tissue Characterization Detects Early Cardiac Dysfunction in a Mouse Model of Chemotherapy-Induced Cardiotoxicity. NMR IN BIOMEDICINE 2020; 33:e4327. [PMID: 32567177 DOI: 10.1002/nbm.4327] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 04/14/2020] [Accepted: 05/06/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Doxorubicin and doxorubicin-trastuzumab combination chemotherapy have been associated with cardiotoxicity that eventually leads to heart failure and may limit dose-effective cancer treatment. Current diagnostic strategies rely on decreased ejection fraction (EF) to diagnose cardiotoxicity. PURPOSE The aim of this study is to explore the potential of cardiac MR (CMR) imaging to identify imaging biomarkers in a mouse model of chemotherapy-induced cardiotoxicity. METHODS A cumulative dose of 25 mg/kg doxorubicin was administered over three weeks using subcutaneous pellets (n = 9, Dox). Another group (n = 9) received same dose of Dox and a total of 10 mg/kg trastuzumab (DT). Mice were imaged at baseline, 5/6 weeks and 10 weeks post-treatment on a 7T MRI system. The protocol included short-axis cine MRI covering the left ventricle (LV) and mid-ventricular short-axis tissue phase mapping (TPM), pre- and post-contrast T1 mapping, T2 mapping and Displacement Encoding with Stimulated Echoes (DENSE) strain encoded MRI. EF, peak myocardial velocities, native T1, T2, extracellular volume (ECV), and myocardial strain were quantified. N = 7 mice were sacrificed for histopathologic assessment of apoptosis at 5/6 weeks. RESULTS Global peak systolic longitudinal velocity was reduced at 5/6 weeks in Dox (0.6 ± 0.3 vs 0.9 ± 0.3, p = 0.02). In the Dox group, native T1 was reduced at 5/6 weeks (1.3 ± 0.2 ms vs 1.6 ± 0.2 ms, p = 0.02), and relatively normalized at week 10 (1.4 ± 0.1 ms vs 1.6 ± 0.2 ms, p > 0.99). There was no change in EF and other MRI parameters and histopathologic results demonstrated minimal apoptosis in all mice (~1-2 apoptotic cell/high power field), suggesting early-stage cardiotoxicity. CONCLUSIONS In a mouse model of chemotherapy-induced cardiotoxicity using doxorubicin and trastuzumab, advanced CMR shows promise in identifying treatment-related decrease in myocardial velocity and native T1 prior to the onset of cardiomyocyte apoptosis and reduction of EF.
Collapse
Affiliation(s)
- Nivedita K Naresh
- Department of Radiology, Northwestern University, 737 N. Michigan Ave, Chicago, IL, USA
| | - Sol Misener
- Department of Radiology, Northwestern University, 737 N. Michigan Ave, Chicago, IL, USA
| | - Zhouli Zhang
- Department of Radiology, Northwestern University, 737 N. Michigan Ave, Chicago, IL, USA
| | - Cynthia Yang
- Department of Radiology, Northwestern University, 737 N. Michigan Ave, Chicago, IL, USA
| | - Alexander Ruh
- Department of Radiology, Northwestern University, 737 N. Michigan Ave, Chicago, IL, USA
| | - Nicola Bertolino
- Department of Radiology, Northwestern University, 737 N. Michigan Ave, Chicago, IL, USA
| | - Frederick H Epstein
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Jeremy D Collins
- Department of Radiology, Northwestern University, 737 N. Michigan Ave, Chicago, IL, USA
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | - Michael Markl
- Department of Radiology, Northwestern University, 737 N. Michigan Ave, Chicago, IL, USA
- McCormick School of Engineering, Northwestern University, Chicago, IL, USA
| | - Daniele Procissi
- Department of Radiology, Northwestern University, 737 N. Michigan Ave, Chicago, IL, USA
| | - James C Carr
- Department of Radiology, Northwestern University, 737 N. Michigan Ave, Chicago, IL, USA
| | - Bradley A Allen
- Department of Radiology, Northwestern University, 737 N. Michigan Ave, Chicago, IL, USA
| |
Collapse
|
3
|
Riedl KA, Kampf T, Herold V, Behr VC, Bauer WR. Wall shear stress analysis using 17.6 Tesla MRI: A longitudinal study in ApoE-/- mice with histological analysis. PLoS One 2020; 15:e0238112. [PMID: 32857805 PMCID: PMC7454980 DOI: 10.1371/journal.pone.0238112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 08/10/2020] [Indexed: 12/31/2022] Open
Abstract
This longitudinal study was performed to evaluate the feasibility of detecting the interaction between wall shear stress (WSS) and plaque development. 20 ApoE-/- mice were separated in 12 mice with Western Diet and 8 mice with Chow Diet. Magnetic resonance (MR) scans at 17.6 Tesla and histological analysis were performed after one week, eight and twelve weeks. All in vivo MR measurements were acquired using a flow sensitive phase contrast method for determining vectorial flow. Histological sections were stained with Hematoxylin and Eosin, Elastica van Gieson and CD68 staining. Data analysis was performed using Ensight and a Matlab-based “Flow Tool”. The body weight of ApoE-/- mice increased significantly over 12 weeks. WSS values increased in the Western Diet group over the time period; in contrast, in the Chow Diet group the values decreased from the first to the second measurement point. Western Diet mice showed small plaque formations with elastin fragmentations after 8 weeks and big plaque formations after 12 weeks; Chow Diet mice showed a few elastin fragmentations after 8 weeks and small plaque formations after 12 weeks. Favored by high-fat diet, plaque formation results in higher values of WSS. With wall shear stress being a known predictor for atherosclerotic plaque development, ultra highfield MRI can serve as a tool for studying the causes and beginnings of atherosclerosis.
Collapse
Affiliation(s)
- Katharina A. Riedl
- Department of Experimental Physics V, University of Würzburg, Würzburg, Germany
- Department of Cardiology, University Heart & Vascular Center Hamburg, Hamburg, Germany
- * E-mail:
| | - Thomas Kampf
- Department of Experimental Physics V, University of Würzburg, Würzburg, Germany
- Department of Diagnostic and Interventional Neuroradiology, University Hospital Würzburg, Würzburg, Germany
| | - Volker Herold
- Department of Experimental Physics V, University of Würzburg, Würzburg, Germany
| | - Volker C. Behr
- Department of Experimental Physics V, University of Würzburg, Würzburg, Germany
| | - Wolfgang R. Bauer
- Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany
| |
Collapse
|
4
|
Vanhoutte L, Gerber BL, Gallez B, Po C, Magat J, Balligand JL, Feron O, Moniotte S. High field magnetic resonance imaging of rodents in cardiovascular research. Basic Res Cardiol 2016; 111:46. [PMID: 27287250 DOI: 10.1007/s00395-016-0565-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 06/01/2016] [Indexed: 02/07/2023]
Abstract
Transgenic and gene knockout rodent models are primordial to study pathophysiological processes in cardiovascular research. Over time, cardiac MRI has become a gold standard for in vivo evaluation of such models. Technical advances have led to the development of magnets with increasingly high field strength, allowing specific investigation of cardiac anatomy, global and regional function, viability, perfusion or vascular parameters. The aim of this report is to provide a review of the various sequences and techniques available to image mice on 7-11.7 T magnets and relevant to the clinical setting in humans. Specific technical aspects due to the rise of the magnetic field are also discussed.
Collapse
Affiliation(s)
- Laetitia Vanhoutte
- Department of Paediatric Cardiology, Cliniques universitaires Saint Luc, Université Catholique de Louvain (UCL), Brussels, Belgium. .,Pole of Pharmacology and Therapeutics (FATH), Institute of Experimental and Clinical Research (IREC), Université Catholique de Louvain (UCL), Brussels, Belgium.
| | - Bernhard L Gerber
- Division of Cardiology, Cliniques universitaires Saint Luc, Université Catholique de Louvain (UCL), Brussels, Belgium.,Pole of Cardiovascular Research (CARD), Institute of Experimental and Clinical Research (IREC), Université Catholique de Louvain (UCL), Brussels, Belgium
| | - Bernard Gallez
- Biomedical Magnetic Resonance Unit (REMA), Louvain Drug Research Institute (LDRI), Université Catholique de Louvain (UCL), Brussels, Belgium
| | - Chrystelle Po
- CNRS, ICube, FMTS, Institut de Physique Biologique, Faculté de Médecine, Université de Strasbourg, Strasbourg, France
| | - Julie Magat
- L'Institut de RYthmologie et de Modélisation Cardiaque (LIRYC), Inserm U1045, Bordeaux, France
| | - Jean-Luc Balligand
- Pole of Pharmacology and Therapeutics (FATH), Institute of Experimental and Clinical Research (IREC), Université Catholique de Louvain (UCL), Brussels, Belgium
| | - Olivier Feron
- Pole of Pharmacology and Therapeutics (FATH), Institute of Experimental and Clinical Research (IREC), Université Catholique de Louvain (UCL), Brussels, Belgium
| | - Stéphane Moniotte
- Department of Paediatric Cardiology, Cliniques universitaires Saint Luc, Université Catholique de Louvain (UCL), Brussels, Belgium
| |
Collapse
|
5
|
Nayak KS, Nielsen JF, Bernstein MA, Markl M, D Gatehouse P, M Botnar R, Saloner D, Lorenz C, Wen H, S Hu B, Epstein FH, N Oshinski J, Raman SV. Cardiovascular magnetic resonance phase contrast imaging. J Cardiovasc Magn Reson 2015; 17:71. [PMID: 26254979 PMCID: PMC4529988 DOI: 10.1186/s12968-015-0172-7] [Citation(s) in RCA: 154] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 07/16/2015] [Indexed: 11/10/2022] Open
Abstract
Cardiovascular magnetic resonance (CMR) phase contrast imaging has undergone a wide range of changes with the development and availability of improved calibration procedures, visualization tools, and analysis methods. This article provides a comprehensive review of the current state-of-the-art in CMR phase contrast imaging methodology, clinical applications including summaries of past clinical performance, and emerging research and clinical applications that utilize today's latest technology.
Collapse
Affiliation(s)
- Krishna S Nayak
- Ming Hsieh Department of Electrical Engineering, University of Southern California, 3740 McClintock Ave, EEB 406, Los Angeles, California, 90089-2564, USA.
| | - Jon-Fredrik Nielsen
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA.
| | | | - Michael Markl
- Department of Radiology, Northwestern University, Chicago, IL, USA.
| | - Peter D Gatehouse
- Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.
| | - Rene M Botnar
- Cardiovascular Imaging, Imaging Sciences Division, Kings's College London, London, UK.
| | - David Saloner
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA.
| | - Christine Lorenz
- Center for Applied Medical Imaging, Siemens Corporation, Baltimore, MD, USA.
| | - Han Wen
- Imaging Physics Laboratory, National Heart Lung and Blood Institute, Bethesda, MD, USA.
| | - Bob S Hu
- Palo Alto Medical Foundation, Palo Alto, CA, USA.
| | - Frederick H Epstein
- Departments of Radiology and Biomedical Engineering, University of Virginia, Charlottesville, VA, USA.
| | - John N Oshinski
- Departments of Radiology and Biomedical Engineering, Emory University School of Medicine, Atlanta, GA, USA.
| | - Subha V Raman
- Division of Cardiovascular Medicine, The Ohio State University, Columbus, OH, USA.
| |
Collapse
|
6
|
Bakermans AJ, Abdurrachim D, Moonen RPM, Motaal AG, Prompers JJ, Strijkers GJ, Vandoorne K, Nicolay K. Small animal cardiovascular MR imaging and spectroscopy. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2015; 88-89:1-47. [PMID: 26282195 DOI: 10.1016/j.pnmrs.2015.03.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 03/09/2015] [Accepted: 03/09/2015] [Indexed: 06/04/2023]
Abstract
The use of MR imaging and spectroscopy for studying cardiovascular disease processes in small animals has increased tremendously over the past decade. This is the result of the remarkable advances in MR technologies and the increased availability of genetically modified mice. MR techniques provide a window on the entire timeline of cardiovascular disease development, ranging from subtle early changes in myocardial metabolism that often mark disease onset to severe myocardial dysfunction associated with end-stage heart failure. MR imaging and spectroscopy techniques play an important role in basic cardiovascular research and in cardiovascular disease diagnosis and therapy follow-up. This is due to the broad range of functional, structural and metabolic parameters that can be quantified by MR under in vivo conditions non-invasively. This review describes the spectrum of MR techniques that are employed in small animal cardiovascular disease research and how the technological challenges resulting from the small dimensions of heart and blood vessels as well as high heart and respiratory rates, particularly in mice, are tackled.
Collapse
Affiliation(s)
- Adrianus J Bakermans
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Desiree Abdurrachim
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Rik P M Moonen
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Abdallah G Motaal
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Jeanine J Prompers
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Gustav J Strijkers
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Katrien Vandoorne
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Klaas Nicolay
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.
| |
Collapse
|
7
|
Meßner NM, Zöllner FG, Kalayciyan R, Schad LR. Pre-clinical functional Magnetic Resonance Imaging Part II: The heart. Z Med Phys 2014; 24:307-22. [PMID: 25023418 DOI: 10.1016/j.zemedi.2014.06.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 05/09/2014] [Accepted: 06/17/2014] [Indexed: 12/21/2022]
Abstract
One third of all deaths worldwide in 2008 were caused by cardiovascular diseases (CVD), and the incidence of CVD related deaths rises ever more. Thus, improved imaging techniques and modalities are needed for the evaluation of cardiac morphology and function. Cardiac magnetic resonance imaging (CMRI) is a minimally invasive technique that is increasingly important due to its high spatial and temporal resolution, its high soft tissue contrast and its ability of functional and quantitative imaging. It is widely accepted as the gold standard of cardiac functional analysis. In the short period of small animal MRI, remarkable progress has been achieved concerning new, fast imaging schemes as well as purpose-built equipment. Dedicated small animal scanners allow for tapping the full potential of recently developed animal models of cardiac disease. In this paper, we review state-of-the-art cardiac magnetic resonance imaging techniques and applications in small animals at ultra-high fields (UHF).
Collapse
Affiliation(s)
- Nadja M Meßner
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Frank G Zöllner
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
| | - Raffi Kalayciyan
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Lothar R Schad
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| |
Collapse
|
8
|
Winter P, Kampf T, Helluy X, Gutjahr FT, Meyer CB, Rommel, Bauer WR, Jakob PM, Herold V. Fast retrospectively triggered local pulse-wave velocity measurements in mice with CMR-microscopy using a radial trajectory. J Cardiovasc Magn Reson 2013; 15:88. [PMID: 24083810 PMCID: PMC3850985 DOI: 10.1186/1532-429x-15-88] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 09/03/2013] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND The aortic pulse-wave velocity (PWV) is an important indicator of cardiovascular risk. In recent studies MRI methods have been developed to measure this parameter noninvasively in mice. Present techniques require additional hardware for cardiac and respiratory gating. In this work a robust self-gated measurement of the local PWV in mice without the need of triggering probes is proposed. METHODS The local PWV of 6-months-old wild-type C57BL/6J mice (n=6) was measured in the abdominal aorta with a retrospectively triggered radial Phase Contrast (PC) MR sequence using the flow-area (QA) method. A navigator signal was extracted from the CMR data of highly asymmetric radial projections with short repetition time (TR=3 ms) and post-processed with high-pass and low-pass filters for retrospective cardiac and respiratory gating. The self-gating signal was used for a reconstruction of high-resolution Cine frames of the aortic motion. To assess the local PWV the volume flow Q and the cross-sectional area A of the aorta were determined. The results were compared with the values measured with a triggered Cartesian and an undersampled triggered radial PC-Cine sequence. RESULTS In all examined animals a self-gating signal could be extracted and used for retrospective breath-gating and PC-Cine reconstruction. With the non-triggered measurement PWV values of 2.3±0.2 m/s were determined. These values are in agreement with those measured with the triggered Cartesian (2.4±0.2 m/s) and the triggered radial (2.3±0.2 m/s) measurement. Due to the strong robustness of the radial trajectory against undersampling an acceleration of more than two relative to the prospectively triggered Cartesian sampling could be achieved with the retrospective method. CONCLUSION With the radial flow-encoding sequence the extraction of a self-gating signal is feasible. The retrospective method enables a robust and fast measurement of the local PWV without the need of additional trigger hardware.
Collapse
Affiliation(s)
- Patrick Winter
- Julius-Maximilians-Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, 97074, Würzburg, Germany
| | - Thomas Kampf
- Julius-Maximilians-Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, 97074, Würzburg, Germany
| | - Xavier Helluy
- Julius-Maximilians-Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, 97074, Würzburg, Germany
| | - Fabian T Gutjahr
- Julius-Maximilians-Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, 97074, Würzburg, Germany
| | - Cord B Meyer
- Julius-Maximilians-Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, 97074, Würzburg, Germany
| | - Rommel
- Julius-Maximilians-Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, 97074, Würzburg, Germany
| | - Wolfgang R Bauer
- Julius-Maximilians-Universität Würzburg, Medizinische Universitätsklinik, Josef-Schneider Straße 4, 97080, Würzburg, Germany
| | - Peter M Jakob
- Julius-Maximilians-Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, 97074, Würzburg, Germany
| | - Volker Herold
- Julius-Maximilians-Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, 97074, Würzburg, Germany
| |
Collapse
|
9
|
Espe EKS, Aronsen JM, Skårdal K, Schneider JE, Zhang L, Sjaastad I. Novel insight into the detailed myocardial motion and deformation of the rodent heart using high-resolution phase contrast cardiovascular magnetic resonance. J Cardiovasc Magn Reson 2013; 15:82. [PMID: 24034168 PMCID: PMC3848852 DOI: 10.1186/1532-429x-15-82] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 09/03/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Phase contrast velocimetry cardiovascular magnetic resonance (PC-CMR) is a powerful and versatile tool allowing assessment of in vivo motion of the myocardium. However, PC-CMR is sensitive to motion related artifacts causing errors that are geometrically systematic, rendering regional analysis of myocardial function challenging. The objective of this study was to establish an optimized PC-CMR method able to provide novel insight in the complex regional motion and strain of the rodent myocardium, and provide a proof-of-concept in normal and diseased rat hearts with higher temporal and spatial resolution than previously reported. METHODS A PC-CMR protocol optimized for assessing the motion and deformation of the myocardium in rats with high spatiotemporal resolution was established, and ten animals with different degree of cardiac dysfunction underwent examination and served as proof-of-concept. Global and regional myocardial velocities and circumferential strain were calculated, and the results were compared to five control animals. Furthermore, the global strain measurements were validated against speckle-tracking echocardiography, and inter- and intrastudy variability of the protocol were evaluated. RESULTS The presented method allows assessment of regional myocardial function in rats with high level of detail; temporal resolution was 3.2 ms, and analysis was done using 32 circumferential segments. In the dysfunctional hearts, global and regional function were distinctly altered, including reduced global peak values, increased regional heterogeneity and increased index of dyssynchrony. Strain derived from the PC-CMR data was in excellent agreement with echocardiography (r = 0.95, p < 0.001; limits-of-agreement -0.02 ± 3.92%strain), and intra- and interstudy variability were low for both velocity and strain (limits-of-agreement, radial motion: 0.01 ± 0.32 cm/s and -0.06 ± 0.75 cm/s; circumferential strain: -0.16 ± 0.89%strain and -0.71 ± 1.67%strain, for intra- and interstudy, respectively). CONCLUSION We demonstrate, for the first time, that PC-CMR enables high-resolution evaluation of in vivo circumferential strain in addition to myocardial motion of the rat heart. In combination with the superior geometric robustness of CMR, this ultimately provides a tool for longitudinal studies of regional function in rodents with high level of detail.
Collapse
Affiliation(s)
- Emil KS Espe
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Kirkeveien 166, N-0407, Oslo, Norway
- KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Jan Magnus Aronsen
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Kirkeveien 166, N-0407, Oslo, Norway
- KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
- Bjørknes College, Oslo, Norway
| | - Kristine Skårdal
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Kirkeveien 166, N-0407, Oslo, Norway
- KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | | | - Lili Zhang
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Kirkeveien 166, N-0407, Oslo, Norway
- KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Ivar Sjaastad
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Kirkeveien 166, N-0407, Oslo, Norway
- KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| |
Collapse
|
10
|
Hoerr V, Nagelmann N, Nauerth A, Kuhlmann MT, Stypmann J, Faber C. Cardiac-respiratory self-gated cine ultra-short echo time (UTE) cardiovascular magnetic resonance for assessment of functional cardiac parameters at high magnetic fields. J Cardiovasc Magn Reson 2013; 15:59. [PMID: 23826850 PMCID: PMC3707860 DOI: 10.1186/1532-429x-15-59] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 06/19/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND To overcome flow and electrocardiogram-trigger artifacts in cardiovascular magnetic resonance (CMR), we have implemented a cardiac and respiratory self-gated cine ultra-short echo time (UTE) sequence. We have assessed its performance in healthy mice by comparing the results with those obtained with a self-gated cine fast low angle shot (FLASH) sequence and with echocardiography. METHODS 2D self-gated cine UTE (TE/TR = 314 μs/6.2 ms, resolution: 129 × 129 μm, scan time per slice: 5 min 5 sec) and self-gated cine FLASH (TE/TR = 3 ms/6.2 ms, resolution: 129 × 129 μm, scan time per slice: 4 min 49 sec) images were acquired at 9.4 T. Volume of the left and right ventricular (LV, RV) myocardium as well as the end-diastolic and -systolic volume was segmented manually in MR images and myocardial mass, stroke volume (SV), ejection fraction (EF) and cardiac output (CO) were determined. Statistical differences were analyzed by using Student t test and Bland-Altman analyses. RESULTS Self-gated cine UTE provided high quality images with high contrast-to-noise ratio (CNR) also for the RV myocardium (CNRblood-myocardium = 25.5 ± 7.8). Compared to cine FLASH, susceptibility, motion, and flow artifacts were considerably reduced due to the short TE of 314 μs. The aortic valve was clearly discernible over the entire cardiac cycle. Myocardial mass, SV, EF and CO determined by self-gated UTE were identical to the values measured with self-gated FLASH and showed good agreement to the results obtained by echocardiography. CONCLUSIONS Self-gated UTE allows for robust measurement of cardiac parameters of diagnostic interest. Image quality is superior to self-gated FLASH, rendering the method a powerful alternative for the assessment of cardiac function at high magnetic fields.
Collapse
Affiliation(s)
- Verena Hoerr
- Department of Clinical Radiology, University Hospital Muenster, Muenster, Germany
| | - Nina Nagelmann
- Department of Clinical Radiology, University Hospital Muenster, Muenster, Germany
| | | | | | - Jörg Stypmann
- Department of Cardiovascular Medicine, Division of Cardiology, University Hospital Muenster, Muenster, Germany
| | - Cornelius Faber
- Department of Clinical Radiology, University Hospital Muenster, Muenster, Germany
| |
Collapse
|
11
|
Akki A, Gupta A, Weiss RG. Magnetic resonance imaging and spectroscopy of the murine cardiovascular system. Am J Physiol Heart Circ Physiol 2013; 304:H633-48. [PMID: 23292717 DOI: 10.1152/ajpheart.00771.2011] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Magnetic resonance imaging (MRI) has emerged as a powerful and reliable tool to noninvasively study the cardiovascular system in clinical practice. Because transgenic mouse models have assumed a critical role in cardiovascular research, technological advances in MRI have been extended to mice over the last decade. These have provided critical insights into cardiac and vascular morphology, function, and physiology/pathophysiology in many murine models of heart disease. Furthermore, magnetic resonance spectroscopy (MRS) has allowed the nondestructive study of myocardial metabolism in both isolated hearts and in intact mice. This article reviews the current techniques and important pathophysiological insights from the application of MRI/MRS technology to murine models of cardiovascular disease.
Collapse
Affiliation(s)
- Ashwin Akki
- Division of Cardiology, Department of Medicine, and Division of Magnetic Resonance Research, Department of Radiology, The Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | | | | |
Collapse
|
12
|
Jung B, Odening KE, Dall’Armellina E, Föll D, Menza M, Markl M, Schneider JE. A quantitative comparison of regional myocardial motion in mice, rabbits and humans using in-vivo phase contrast CMR. J Cardiovasc Magn Reson 2012; 14:87. [PMID: 23270566 PMCID: PMC3579745 DOI: 10.1186/1532-429x-14-87] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Accepted: 12/06/2012] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Genetically manipulated animals like mice or rabbits play an important role in the exploration of human cardiovascular diseases. It is therefore important to identify animal models that closely mimic physiological and pathological human cardiac function. METHODS In-vivo phase contrast cardiovascular magnetic resonance (CMR) was used to measure regional three-directional left ventricular myocardial motion with high temporal resolution in mice (N=18), rabbits (N=8), and humans (N=20). Radial, long-axis, and rotational myocardial velocities were acquired in left ventricular basal, mid-ventricular, and apical short-axis locations. RESULTS Regional analysis revealed different patterns of motion: 1) In humans and rabbits, the apex showed slower radial velocities compared to the base. 2) Significant differences within species were seen in the pattern of long-axis motion. Long-axis velocities during systole were fairly homogeneously distributed in mice, whereas humans showed a dominant component in the lateral wall and rabbits in the base. 3) Rotational velocities and twist showed the most distinct patterns in both temporal evolution and relative contribution of base, mid-ventricle and apex, respectively. Interestingly, a marked difference in rotational behavior during early-systole was found in mice, which exhibited clockwise rotation in all slice locations compared to counter-clockwise rotation in rabbits and humans. CONCLUSIONS Phase contrast CMR revealed subtle, but significantly different regional myocardial motion patterns in mice, rabbits and humans. This finding has to be considered when investigating myocardial motion pattern in small animal models of heart disease.
Collapse
Affiliation(s)
- Bernd Jung
- Department of Radiology, Medical Physics, University Medical Center, Freiburg, Germany
| | - Katja E Odening
- Department of Cardiology, University Medical Center, Freiburg, Germany
| | | | - Daniela Föll
- Department of Cardiology, University Medical Center, Freiburg, Germany
| | - Marius Menza
- Department of Radiology, Medical Physics, University Medical Center, Freiburg, Germany
| | - Michael Markl
- Department of Radiology, Northwestern University, Chicago, IL, USA
| | | |
Collapse
|
13
|
Espe EKS, Aronsen JM, Skrbic B, Skulberg VM, Schneider JE, Sejersted OM, Zhang L, Sjaastad I. Improved MR phase-contrast velocimetry using a novel nine-point balanced motion-encoding scheme with increased robustness to eddy current effects. Magn Reson Med 2012; 69:48-61. [PMID: 22392844 DOI: 10.1002/mrm.24226] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Revised: 01/17/2012] [Accepted: 02/04/2012] [Indexed: 01/23/2023]
Abstract
Phase-contrast MRI (PC-MRI) velocimetry is a noninvasive, high-resolution motion assessment tool. However, high motion sensitivity requires strong motion-encoding magnetic gradients, making phase-contrast-MRI prone to baseline shift artifacts due to the generation of eddy currents. In this study, we propose a novel nine-point balanced velocity-encoding strategy, designed to be more accurate in the presence of strong and rapidly changing gradients. The proposed method was validated using a rotating phantom, and its robustness and precision were explored and compared with established approaches through computer simulations and in vivo experiments. Computer simulations yielded a 39-57% improvement in velocity-noise ratio (corresponding to a 27-33% reduction in measurement error), depending on which method was used for comparison. Moreover, in vivo experiments confirmed this by demonstrating a 26-53% reduction in accumulated velocity error over the R-R interval. The nine-point balanced phase-contrast-MRI-encoding strategy is likely useful for settings where high spatial and temporal resolution and/or high motion sensitivity is required, such as in high-resolution rodent myocardial tissue phase mapping.
Collapse
Affiliation(s)
- Emil K S Espe
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway.
| | | | | | | | | | | | | | | |
Collapse
|
14
|
Dall'Armellina E, Jung BA, Lygate CA, Neubauer S, Markl M, Schneider JE. Improved method for quantification of regional cardiac function in mice using phase-contrast MRI. Magn Reson Med 2012; 67:541-51. [PMID: 21674616 PMCID: PMC3378699 DOI: 10.1002/mrm.23022] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Revised: 04/04/2011] [Accepted: 05/05/2011] [Indexed: 11/08/2022]
Abstract
Phase-contrast magnetic resonance imaging is a technique that allows for characterization of regional cardiac function and for measuring transmural myocardial velocities in human hearts with high temporal and spatial resolution. The application of this technique (also known as tissue phase mapping) to murine hearts has been very limited so far. The aim of our study was to implement and to optimize tissue phase mapping for a comprehensive assessment of murine transmural wall motion. Baseline values for regional motion patterns in mouse hearts, based on the clinically used American Heart Association's 17-segment model, were established, and a detailed motion analysis of mouse heart for the entire cardiac cycle (including epicardial and endocardial motion patterns) is provided. Black-blood contrast was found to be essential to obtain reproducible velocity encoding. Tissue phase mapping of the mouse heart permits the detailed assessment of regional myocardial velocities. While a proof-of-principle application in a murine ischemia-reperfusion model was performed, future studies are warranted to assess its potential for the investigation of systolic and diastolic functions in genetically and surgically manipulated mouse models of human heart disease.
Collapse
Affiliation(s)
- Erica Dall'Armellina
- Department of Cardiovascular Medicine, University of OxfordOxford, United Kingdom
| | - Bernd A Jung
- Department of Radiology, Medical Physics, University Hospital FreiburgGermany
| | - Craig A Lygate
- Department of Cardiovascular Medicine, University of OxfordOxford, United Kingdom
| | - Stefan Neubauer
- Department of Cardiovascular Medicine, University of OxfordOxford, United Kingdom
| | - Michael Markl
- Department of Radiology, Medical Physics, University Hospital FreiburgGermany
| | - Jürgen E Schneider
- Department of Cardiovascular Medicine, University of OxfordOxford, United Kingdom
| |
Collapse
|
15
|
Cardiovascular Magnetic Resonance of Myocardial Structure, Function, and Perfusion in Mouse and Rat Models. CURRENT CARDIOVASCULAR IMAGING REPORTS 2012. [DOI: 10.1007/s12410-012-9122-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
|
16
|
Abstract
High-resolution magnetic resonance cine imaging (cine-MRI) allows for a non-invasive assessment of ventricular function and mass in normal mice and in genetically and surgically modified mouse models of cardiac disease. The assessment of myocardial mass and function by cine-MRI does not rely on geometric assumptions, as the hearts are covered from the base to the apex, typically by a stack of two-dimensional images. The MR data acquisition is then followed by image segmentation of specific cine frames in each slice to obtain geometric and functional parameters, such as end-diastolic volume (EDV), end-systolic volume (ESV) or ejection fraction (EF). This technique has been well established in clinical routine application and it is now also becoming the reference method in experimental cardiovascular MRI. The cine images are typically acquired in short- and long-axis orientations of the heart to facilitate an accurate assessment of cardiac functional parameters. These views can be difficult to identify, particularly in animals with diseased hearts. Furthermore, data analysis can be the source of a systematic error, mainly for myocardial mass measurement. We have established protocols that allow for a quick and reproducible way of obtaining the relevant cardiac views for cine-MRI, and for accurate image analysis.
Collapse
|
17
|
Botnar RM, Makowski MR. Cardiovascular magnetic resonance imaging in small animals. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2012; 105:227-61. [PMID: 22137434 DOI: 10.1016/b978-0-12-394596-9.00008-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Noninvasive imaging studies involving small animals are becoming increasingly important in preclinical pharmacological, genetic, and biomedical cardiovascular research. Especially small animal magnetic resonance imaging (MRI) using high field and clinical MRI systems has gained significant importance in recent years. Compared to other imaging modalities, like computer tomography, MRI can provide an excellent soft tissue contrast, which enables the characterization of different kinds of tissues without the use of contrast agents. In addition, imaging can be performed with high spatial and temporal resolution. Small animal MRI cannot only provide anatomical information about the beating murine heart; it can also provide functional and molecular information, which makes it a unique imaging modality. Compared to clinical MRI examinations in humans, small animal MRI is associated with additional challenges. These included a smaller size of all cardiovascular structures and a up to ten times higher heart rate. Dedicated small animal monitoring devices make a reliable cardiac triggering and respiratory gating feasible. MRI in combination with molecular probes enables the noninvasive imaging of biological processes at a molecular level. Different kinds of iron oxide or gadolinium-based contrast agents can be used for this purpose. Compared to other molecular imaging modalities, like single photon emission computed tomography (SPECT) and positron emission tomography (PET), MRI can also provide imaging with high spatial resolution, which is of high importance for the assessment of the cardiovascular system. The sensitivity for detection of MRI contrast agents is however lower compared to sensitivity of radiation associated techniques like PET and SPECT. This chapter is divided into the following sections: (1) "Introduction," (2) "Principals of Magnetic Resonance Imaging," (3) "MRI Systems for Preclinical Imaging and Experimental Setup," and (4) "Cardiovascular Magnetic Resonance Imaging."
Collapse
Affiliation(s)
- René M Botnar
- Division of Imaging Sciences, King's College London, London, United Kingdom
| | | |
Collapse
|
18
|
Zhong X, Gibberman LB, Spottiswoode BS, Gilliam AD, Meyer CH, French BA, Epstein FH. Comprehensive cardiovascular magnetic resonance of myocardial mechanics in mice using three-dimensional cine DENSE. J Cardiovasc Magn Reson 2011; 13:83. [PMID: 22208954 PMCID: PMC3278394 DOI: 10.1186/1532-429x-13-83] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Accepted: 12/30/2011] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Quantitative noninvasive imaging of myocardial mechanics in mice enables studies of the roles of individual genes in cardiac function. We sought to develop comprehensive three-dimensional methods for imaging myocardial mechanics in mice. METHODS A 3D cine DENSE pulse sequence was implemented on a 7T small-bore scanner. The sequence used three-point phase cycling for artifact suppression and a stack-of-spirals k-space trajectory for efficient data acquisition. A semi-automatic 2D method was adapted for 3D image segmentation, and automated 3D methods to calculate strain, twist, and torsion were employed. A scan protocol that covered the majority of the left ventricle in a scan time of less than 25 minutes was developed, and seven healthy C57Bl/6 mice were studied. RESULTS Using these methods, multiphase normal and shear strains were measured, as were myocardial twist and torsion. Peak end-systolic values for the normal strains at the mid-ventricular level were 0.29 ± 0.17, -0.13 ± 0.03, and -0.18 ± 0.14 for E(rr), E(cc), and E(ll), respectively. Peak end-systolic values for the shear strains were 0.00 ± 0.08, 0.04 ± 0.12, and 0.03 ± 0.07 for E(rc), E(rl), and E(cl), respectively. The peak end-systolic normalized torsion was 5.6 ± 0.9°. CONCLUSIONS Using a 3D cine DENSE sequence tailored for cardiac imaging in mice at 7 T, a comprehensive assessment of 3D myocardial mechanics can be achieved with a scan time of less than 25 minutes and an image analysis time of approximately 1 hour.
Collapse
Affiliation(s)
| | | | - Bruce S Spottiswoode
- MRC/UCT Medical Imaging Research Unit, University of Cape Town, Cape Town, South Africa
| | | | - Craig H Meyer
- Radiology Department, University of Virginia, Charlottesville, USA
- Biomedical Engineering Department, University of Virginia, Charlottesville, USA
| | - Brent A French
- Biomedical Engineering Department, University of Virginia, Charlottesville, USA
| | - Frederick H Epstein
- Radiology Department, University of Virginia, Charlottesville, USA
- Biomedical Engineering Department, University of Virginia, Charlottesville, USA
| |
Collapse
|
19
|
WONG KELVINKL, KELSO RICHARDM, WORTHLEY SG, SANDERS P, MAZUMDAR J, ABBOTT D. MEDICAL IMAGING AND PROCESSING METHODS FOR CARDIAC FLOW RECONSTRUCTION. J MECH MED BIOL 2011. [DOI: 10.1142/s0219519409002894] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Intra-cardiac blood flow imaging and visualization is challenging due to the processes involved in generating velocity fields of flow within specific chambers of interest. Visual analysis of cardiac flow or wall deformation is crucial for an accurate examination of the heart. Cardiac chamber boundary encapsulation is one of the key implementations for region definition. To provide intelligible results describing flow within the human heart, cardiac chamber segmentation is a pre-requisite so that fluid motion information can be presented within a region of interest defined by the chamber boundary. A technique that is used to establish contouring along the cardiac wall is described mathematically. This article also sets the practical foundation for flow vector synthesis and visualization in the cardiac discipline. We have outlined conceptual development and the construction of flow field based on a three-dimensional Cartesian grid that can give a greater insight into the blood dynamics within the heart. We developed a framework that is able to present both anatomical as well as flow information by overlaying velocity fields over medical images and displaying them in cine-mode. By addressing most of the methods involved from the programming perspective, procedural execution and memory efficiency have been considered. Our implemented system can be used to examine abnormal blood motion behaviour or discover flow phenomena in normal or defective hearts.
Collapse
Affiliation(s)
- KELVIN K. L. WONG
- Center for Biomedical Engineering and School of Electrical & Electronics Engineering, University of Adelaide, SA 5005, Australia
| | - RICHARD M. KELSO
- School of Mechanical Engineering, University of Adelaide, SA 5005, Australia
| | - S. G. WORTHLEY
- Cardiovascular Research Centre, Royal Adelaide Hospital and School of Medicine, University of Adelaide, SA 5005, Australia
| | - P. SANDERS
- Cardiovascular Research Centre, Royal Adelaide Hospital and School of Medicine, University of Adelaide, SA 5005, Australia
| | - J. MAZUMDAR
- Center for Biomedical Engineering and School of Electrical & Electronics Engineering, University of Adelaide, SA 5005, Australia
| | - D. ABBOTT
- Center for Biomedical Engineering and School of Electrical & Electronics Engineering, University of Adelaide, SA 5005, Australia
| |
Collapse
|
20
|
Schneider JE, Lanz T, Barnes H, Stork LA, Bohl S, Lygate CA, Ordidge RJ, Neubauer S. Accelerated cardiac magnetic resonance imaging in the mouse using an eight-channel array at 9.4 Tesla. Magn Reson Med 2011; 65:60-70. [PMID: 20740650 PMCID: PMC3021721 DOI: 10.1002/mrm.22605] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
MRI has become an important tool to noninvasively assess global and regional cardiac function, infarct size, or myocardial blood flow in surgically or genetically modified mouse models of human heart disease. Constraints on scan time due to sensitivity to general anesthesia in hemodynamically compromised mice frequently limit the number of parameters available in one imaging session. Parallel imaging techniques to reduce acquisition times require coil arrays, which are technically challenging to design at ultrahigh magnetic field strengths. This work validates the use of an eight-channel volume phased-array coil for cardiac MRI in mice at 9.4 T. Two- and three-dimensional sequences were combined with parallel imaging techniques and used to quantify global cardiac function, T(1)-relaxation times and infarct sizes. Furthermore, the rapid acquisition of functional cine-data allowed for the first time in mice measurement of left-ventricular peak filling and ejection rates under intravenous infusion of dobutamine. The results demonstrate that a threefold accelerated data acquisition is generally feasible without compromising the accuracy of the results. This strategy may eventually pave the way for routine, multiparametric phenotyping of mouse hearts in vivo within one imaging session of tolerable duration.
Collapse
Affiliation(s)
- Jürgen E Schneider
- British Heart Foundation Experimental MR Unit (BMRU), Department of Cardiovascular Medicine, University of Oxford, Oxford OX3 7BN, United Kingdom.
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Abstract
Molecular imaging with targeted contrast agents by magnetic resonance imaging (MRI) allows for the noninvasive detection and characterization of biological changes on a molecular level. In this article, the principles of molecular MRI and its applications in cardiovascular diseases are reviewed. First, basic properties of positive and negative contrast agents are introduced and their effect on signal generation in a magnetic field is described. In the next part, different types of MRI scanners and the influence of field strength on signal properties of contrast agents for molecular imaging are discussed. Additionally, the assessment, analysis, and quantification of the changes in T1 and T2* relaxation time induced by the different molecular contrast agents are reviewed. Finally, the basic mechanisms of targeting of imaging probes on a molecular level and recent applications of molecular MRI in cardiovascular disease are reviewed.
Collapse
|
22
|
Zhong J, Yu X. Strain and torsion quantification in mouse hearts under dobutamine stimulation using 2D multiphase MR DENSE. Magn Reson Med 2010; 64:1315-22. [PMID: 20740659 DOI: 10.1002/mrm.22530] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2009] [Revised: 05/13/2010] [Accepted: 05/17/2010] [Indexed: 11/08/2022]
Abstract
In this study, a 2D multiphase magnetic resonance displacement encoding with stimulated echoes (DENSE) imaging and analysis method was developed for direct quantification of Lagrangian strain in the mouse heart. Using the proposed method, <10 ms temporal resolution and 0.56 mm in-plane resolution were achieved. A validation study that compared strain calculation by displacement encoding with stimulated echoes and by magnetic resonance tagging showed high correlation between the two methods (R(2) > 0.80). Regional ventricular wall strain and twist were characterized in mouse hearts at baseline and under dobutamine stimulation. Dobutamine stimulation induced significant increase in radial and circumferential strains and torsion at peak systole. A rapid untwisting was also observed during early diastole. This work demonstrates the capability of characterizing cardiac functional response to dobutamine stimulation in the mouse heart using 2D multiphase magnetic resonance displacement encoding with stimulated echoes.
Collapse
Affiliation(s)
- Jia Zhong
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA
| | | |
Collapse
|
23
|
Abstract
UNLABELLED The ability to trace or identify specific molecules within a specific anatomic location provides insight into metabolic pathways, tissue components, and tracing of solute transport mechanisms. With the increasing use of small animals for research, such imaging must have sufficiently high spatial resolution to allow anatomic localization as well as sufficient specificity and sensitivity to provide an accurate description of the molecular distribution and concentration. METHODS Imaging methods based on electromagnetic radiation, such as PET, SPECT, MRI, and CT, are increasingly applicable because of recent advances in novel scanner hardware and image reconstruction software and the availability of novel molecules that have enhanced sensitivity in these methodologies. RESULTS Small-animal PET has been advanced by the development of detector arrays that provide higher resolution and positron-emitting elements that allow new molecular tracers to be labeled. Micro-MRI has been improved in terms of spatial resolution and sensitivity through increased magnet field strength and the development of special-purpose coils and associated scan protocols. Of particular interest is the associated ability to image local mechanical function and solute transport processes, which can be directly related to the molecular information. This ability is further strengthened by the synergistic integration of PET with MRI. Micro-SPECT has been improved through the use of coded aperture imaging approaches as well as image reconstruction algorithms that can better deal with the photon-limited scan data. The limited spatial resolution can be partially overcome by integrating SPECT with CT. Micro-CT by itself provides exquisite spatial resolution of anatomy, but recent developments in high-spatial-resolution photon counting and spectrally sensitive imaging arrays, combined with x-ray optical devices, hold promise for actual molecular identification by virtue of the chemical bond lengths of molecules, especially biopolymers. CONCLUSION Given the increasing use of small animals for evaluating new clinical imaging techniques and providing more insight into pathophysiologic phenomena as well as the availability of improved detection systems, scanning protocols, and associated software, the sensitivity and specificity of molecular imaging are increasing.
Collapse
Affiliation(s)
| | | | - Ciprian Catana
- Massachusetts General Hospital and Harvard Medical School, Charlestown MA, U.S.A
| | | | - Erik L. Ritman
- Mayo Clinic College of Medicine, Dept. Physiology and Biomedical Engineering 200 First Street SW Rochester, MN 55905 U.S.A. Phone: 507.2551.1939 Fax: 507.255.1935
| |
Collapse
|
24
|
Makowski MR, Wiethoff AJ, Jansen CHP, Botnar RM. Cardiovascular MRI in small animals. Expert Rev Cardiovasc Ther 2010; 8:35-47. [PMID: 20014933 DOI: 10.1586/erc.09.126] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Imaging studies of cardiovascular disease in small rodents have become a prerequisite in preclinical cardiovascular research. Transgenic and gene-knockout models of cardiovascular diseases enables the investigation of the influence of single genes or groups of genes on disease pathogenesis. In addition, experimental and genetically altered models provide valuable in vivo platforms to investigate the efficacy of novel drugs and contrast agents. Owing to the excellent soft tissue contrast, high spatial and temporal resolution, as well as the tomographic nature of MRI, anatomy and function can be assessed with unique accuracy and reproducibility. Furthermore, using novel targeted MRI contrast agents, molecular changes associated with cardiovascular disease can be investigated in the same imaging session. This review focuses on recent advances in hardware, imaging sequences and probe design.
Collapse
Affiliation(s)
- Marcus R Makowski
- Division of Imaging Sciences, King's College London, 4th Floor, Lambeth Wing, St Thomas' Hospital, London SE1 7EH, UK.
| | | | | | | |
Collapse
|
25
|
Cardiac Flow Analysis Applied to Phase Contrast Magnetic Resonance Imaging of the Heart. Ann Biomed Eng 2009; 37:1495-515. [DOI: 10.1007/s10439-009-9709-y] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2008] [Accepted: 04/28/2009] [Indexed: 01/05/2023]
|
26
|
Herold V, Wellen J, Ziener CH, Weber T, Hiller KH, Nordbeck P, Rommel E, Haase A, Bauer WR, Jakob PM, Sarkar SK. In vivo comparison of atherosclerotic plaque progression with vessel wall strain and blood flow velocity in apoE(-/-) mice with MR microscopy at 17.6 T. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2009; 22:159-66. [PMID: 19153787 DOI: 10.1007/s10334-008-0160-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2008] [Revised: 11/14/2008] [Accepted: 11/25/2008] [Indexed: 01/02/2023]
Abstract
OBJECT At present, in vivo plaque characterization in mice by MRI is typically limited to the visualization of vascular lesions with no accompanying analysis of vessel wall function. The aim of this study was to analyze the influence of atherosclerotic plaque development on the morphological and mechanical characteristics of the aortic vessel wall in a pre-clinical murine model of atherosclerosis. MATERIALS AND METHODS Groups of apolipoprotein E-deficient (apoE(-/-)) and C57BL/6J control mice fed a high-fat diet were monitored over a 12-week time period by high-field MRI. Multi-Slice-Multi-Spin-Echo and Phase-Contrast MRI sequences were employed to track changes to aortic vessel wall area, blood flow velocity and distensibility. RESULTS After 6- and 12-weeks, significant changes in vessel wall area and circumferential strain were detected in the apoE(-/-) mice relative to the control animals. Blood flow velocity and intravascular lumen remained unchanged in both groups, findings that are in agreement with the theory of positive remodeling of the ascending aorta during plaque progression. CONCLUSION This study has demonstrated the application of high-field MRI for characterizing the temporal progression of morphological and mechanical changes to murine aortic vasculature associated with atherosclerotic lesion development.
Collapse
Affiliation(s)
- Volker Herold
- Julius-Maximilians-Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, Würzburg, Germany.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Hankiewicz JH, Goldspink PH, Buttrick PM, Lewandowski ED. Principal strain changes precede ventricular wall thinning during transition to heart failure in a mouse model of dilated cardiomyopathy. Am J Physiol Heart Circ Physiol 2008; 294:H330-6. [DOI: 10.1152/ajpheart.01109.2007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study was performed to elucidate the relation between in vivo measurements of two-dimensional principal strains and the progression of left ventricle (LV) wall thinning during development of dilated cardiomyopathy in the protein kinase C-ε (PKC-ε) transgenic (TG) overexpressing mouse heart. Principal two-dimensional strains, E1 and E2, were determined in the LV wall of the anesthetized mouse using cardiac MRI tagging at 14.1 T. PKC-ε TG provided a model of pure dilated cardiomyopathy without evidence of hypertrophy (PKC-ε TG, n = 6). Ejection fraction, wall thickness, and principal strains were determined at 1-mo intervals in hearts of PKC-ε TG vs. age-matched, nontransgenic mice (NTG, n = 5) from age 6 to 13 mo. Through the study, PKC-ε TG displayed lower ejection fraction than NTG. At 7 mo, average principal strain E1 in PKC-ε TG hearts was lower compared with NTG (PKC-ε TG = 0.14 ± 0.03, NTG = 0.19 ± 0.03, P < 0.05). The greatest reductions in regional E1 occurred in the lateral segments. The principal strain E2 did not change significantly in either group. At 9 mo, LV wall thinning occurred in PKC-ε TG mice ( P < 0.01 vs. 8 mo) to 21% below values in NTG ( P < 0.001). Average E1 strain diverged between PKC-ε TG and NTG hearts by 25–43%. These E1 changes preceded LV wall thinning and predated the eventual transition from a compensated circumstance to the dilated phenotype. The findings indicate a near step function in E1 depression that precedes the onset of LV wall thinning and suggest E1 as a prognostic indicator of dilated cardiomyopathy.
Collapse
|
28
|
Abstract
Transgenic and knockout mice can be used to study the genes and basic mechanisms involved in heart disease, and have therefore assumed a central role in modern cardiac research. MRI and MRS techniques have recently been developed for mice that enable the quantitative or semi-quantitative in vivo assessment of cardiac anatomy, function, perfusion, infarction, Ca(2+) influx, and metabolism. With these techniques, the normal mouse heart has been shown to be well suited as a model of human cardiac disease. The roles of individual genes in normal cardiac physiology have recently been studied by MR, including the role of neuronal nitric oxide synthase in beta-adrenergic stimulation, the roles of the inducible nitric oxide synthase and myoglobin in function, dilation, and energetics, and the role of cardiac troponin I in contractility. Furthermore, with a mouse model of myocardial infarction, the roles of the angiotensin II type 2 receptor, xanthine oxidase inhibitors, blood coagulation factor XIII, and inducible nitric oxide synthase in post-infarct function and remodeling have been further elucidated. Non-invasive in vivo MRI and MRS in mice provide a unique and powerful means for phenotyping genetically engineered mice and can improve our understanding of the roles of specific genes and proteins in cardiac physiology and pathophysiology.
Collapse
Affiliation(s)
- Frederick H Epstein
- Departments of Radiology and Biomedical Engineering, and the Cardiovascular Research Center, University of Virginia, Charlottesville, VA 22908, USA.
| |
Collapse
|