1
|
Božić‐Iven M, Rapacchi S, Tao Q, Pierce I, Thornton G, Nitsche C, Treibel TA, Schad LR, Weingärtner S. Improved reproducibility for myocardial ASL: Impact of physiological and acquisition parameters. Magn Reson Med 2024; 91:118-132. [PMID: 37667643 PMCID: PMC10962577 DOI: 10.1002/mrm.29834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 07/26/2023] [Accepted: 07/31/2023] [Indexed: 09/06/2023]
Abstract
PURPOSE To investigate and mitigate the influence of physiological and acquisition-related parameters on myocardial blood flow (MBF) measurements obtained with myocardial Arterial Spin Labeling (myoASL). METHODS A Flow-sensitive Alternating Inversion Recovery (FAIR) myoASL sequence with bSSFP and spoiled GRE (spGRE) readout is investigated for MBF quantification. Bloch-equation simulations and phantom experiments were performed to evaluate how variations in acquisition flip angle (FA), acquisition matrix size (AMS), heart rate (HR) and bloodT 1 $$ {\mathrm{T}}_1 $$ relaxation time (T 1 , B $$ {\mathrm{T}}_{1,B} $$ ) affect quantification of myoASL-MBF. In vivo myoASL-images were acquired in nine healthy subjects. A corrected MBF quantification approach was proposed based on subject-specificT 1 , B $$ {\mathrm{T}}_{1,B} $$ values and, for spGRE imaging, subtracting an additional saturation-prepared baseline from the original baseline signal. RESULTS Simulated and phantom experiments showed a strong dependence on AMS and FA (R 2 $$ {R}^2 $$ >0.73), which was eliminated in simulations and alleviated in phantom experiments using the proposed saturation-baseline correction in spGRE. Only a very mild HR dependence (R 2 $$ {R}^2 $$ >0.59) was observed which was reduced when calculating MBF with individualT 1 , B $$ {\mathrm{T}}_{1,B} $$ . For corrected spGRE, in vivo mean global spGRE-MBF ranged from 0.54 to 2.59 mL/g/min and was in agreement with previously reported values. Compared to uncorrected spGRE, the intra-subject variability within a measurement (0.60 mL/g/min), between measurements (0.45 mL/g/min), as well as the inter-subject variability (1.29 mL/g/min) were improved by up to 40% and were comparable with conventional bSSFP. CONCLUSION Our results show that physiological and acquisition-related factors can lead to spurious changes in myoASL-MBF if not accounted for. Using individualT 1 , B $$ {\mathrm{T}}_{1,B} $$ and a saturation-baseline can reduce these variations in spGRE and improve reproducibility of FAIR-myoASL against acquisition parameters.
Collapse
Affiliation(s)
- Maša Božić‐Iven
- Medical Faculty MannheimHeidelberg UniversityMannheimGermany
- Department of Imaging PhysicsDelft University of TechnologyDelftThe Netherlands
| | | | - Qian Tao
- Department of Imaging PhysicsDelft University of TechnologyDelftThe Netherlands
| | - Iain Pierce
- Barts Heart CentreSt Bartholomew's HospitalLondonUK
| | - George Thornton
- Barts Heart CentreSt Bartholomew's HospitalLondonUK
- Institute of Cardiovascular ScienceUniversity College LondonLondonUK
| | - Christian Nitsche
- Barts Heart CentreSt Bartholomew's HospitalLondonUK
- Institute of Cardiovascular ScienceUniversity College LondonLondonUK
- Division of CardiologyMedical University of ViennaViennaAustria
| | - Thomas A. Treibel
- Barts Heart CentreSt Bartholomew's HospitalLondonUK
- Institute of Cardiovascular ScienceUniversity College LondonLondonUK
| | - Lothar R. Schad
- Medical Faculty MannheimHeidelberg UniversityMannheimGermany
| | | |
Collapse
|
2
|
Shah SA, Reagan CE, Bresticker JE, Wolpe AG, Good ME, Macal EH, Billcheck HO, Bradley LA, French BA, Isakson BE, Wolf MJ, Epstein FH. Obesity-Induced Coronary Microvascular Disease Is Prevented by iNOS Deletion and Reversed by iNOS Inhibition. JACC Basic Transl Sci 2023; 8:501-514. [PMID: 37325396 PMCID: PMC10264569 DOI: 10.1016/j.jacbts.2022.11.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 11/02/2022] [Accepted: 11/03/2022] [Indexed: 02/04/2023]
Abstract
Coronary microvascular disease (CMD) caused by obesity and diabetes is major contributor to heart failure with preserved ejection fraction; however, the mechanisms underlying CMD are not well understood. Using cardiac magnetic resonance applied to mice fed a high-fat, high-sucrose diet as a model of CMD, we elucidated the role of inducible nitric oxide synthase (iNOS) and 1400W, an iNOS antagonist, in CMD. Global iNOS deletion prevented CMD along with the associated oxidative stress and diastolic and subclinical systolic dysfunction. The 1400W treatment reversed established CMD and oxidative stress and preserved systolic/diastolic function in mice fed a high-fat, high-sucrose diet. Thus, iNOS may represent a therapeutic target for CMD.
Collapse
Affiliation(s)
- Soham A. Shah
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
| | - Claire E. Reagan
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
| | - Julia E. Bresticker
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
| | - Abigail G. Wolpe
- The Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia, USA
| | - Miranda E. Good
- The Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia, USA
| | - Edgar H. Macal
- The Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia, USA
| | - Helen O. Billcheck
- Department of Cardiovascular Medicine, University of Virginia, Charlottesville, Virginia, USA
| | - Leigh A. Bradley
- Department of Cardiovascular Medicine, University of Virginia, Charlottesville, Virginia, USA
| | - Brent A. French
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Brant E. Isakson
- The Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia, USA
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Matthew J. Wolf
- The Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia, USA
- Department of Cardiovascular Medicine, University of Virginia, Charlottesville, Virginia, USA
| | - Frederick H. Epstein
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
- The Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia, USA
| |
Collapse
|
3
|
Shah SA, Echols JT, Sun C, Wolf MJ, Epstein FH. Accelerated fatty acid composition MRI of epicardial adipose tissue: Development and application to eplerenone treatment in a mouse model of obesity-induced coronary microvascular disease. Magn Reson Med 2022; 88:1734-1747. [PMID: 35726367 PMCID: PMC9339514 DOI: 10.1002/mrm.29348] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 04/23/2022] [Accepted: 05/16/2022] [Indexed: 01/10/2023]
Abstract
Purpose To develop an accelerated MRI method to quantify the epicardial adipose tissue (EAT) fatty acid composition (FAC) and test the hypothesis that eplerenone (EPL) shifts the EAT FAC toward unsaturation in obese mice. Methods Undersampled multi‐echo gradient echo imaging employing a dictionary‐based compressed‐sensing reconstruction and iterative decomposition with echo asymmetry and least‐squares–based mapping (IDEAL) was developed, validated, and used to study EAT in obese mice scanned at 7T. Fully sampled and rate 2, 2.5, 3, and 3.5 undersampled image data were acquired, reconstructed, and assessed using RMSE and structural similarity (SSIM). Two groups of mice were studied: untreated (control, n = 10) and EPL‐treated (n = 10) mice fed a high‐fat high‐sucrose diet. MRI included imaging of EAT FAC, EAT volume, and myocardial perfusion reserve. Results Rate 3 acceleration provided RMSE <5% and structural similarity >0.85 for FAC MRI. After 6 weeks of diet, EPL‐treated compared to untreated mice had a reduced EAT saturated fatty acid fraction (0.27 ± 0.09 vs. 0.39 ± 0.07, P < 0.05) and increased EAT unsaturation degree (4.37 ± 0.32 vs. 3.69 ± 0.58, P < 0.05). Also, EAT volume in EPL‐treated compared to untreated mice was reduced (8.1 ± 0.6 mg vs. 11.4 ± 0.7 mg, P < 0.01), and myocardial perfusion reserve was improved (1.83 ± 0.15 vs. 1.61 ± 0.17, P < 0.05). Conclusion Rate 3 accelerated FAC MRI enabled accurate quantification of EAT FAC in mice. EPL treatment shifted the EAT FAC toward increased unsaturation and was associated with improvement of coronary microvascular function. Click here for author‐reader discussions
Collapse
Affiliation(s)
- Soham A Shah
- Biomedical Engineering, University of Virginia, Charlottesville, VA
| | - John T Echols
- Biomedical Engineering, University of Virginia, Charlottesville, VA
| | - Changyu Sun
- Biomedical Engineering, University of Virginia, Charlottesville, VA.,Biomedical, Biological & Chemical Engineering, University of Missouri, Columbia, MO.,Radiolgy, University of Missouri, Columbia, MO
| | - Matthew J Wolf
- Cardiovascular Medicine, University of Virginia, Charlottesville, VA
| | - Frederick H Epstein
- Biomedical Engineering, University of Virginia, Charlottesville, VA.,Radiology, University of Virginia, Charlottesville, VA
| |
Collapse
|
4
|
Multiparametric MRI identifies subtle adaptations for demarcation of disease transition in murine aortic valve stenosis. Basic Res Cardiol 2022; 117:29. [PMID: 35643805 PMCID: PMC9148878 DOI: 10.1007/s00395-022-00936-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 05/11/2022] [Accepted: 05/12/2022] [Indexed: 02/01/2023]
Abstract
Aortic valve stenosis (AS) is the most frequent valve disease with relevant prognostic impact. Experimental model systems for AS are scarce and comprehensive imaging techniques to simultaneously quantify function and morphology in disease progression are lacking. Therefore, we refined an acute murine AS model to closely mimic human disease characteristics and developed a high-resolution magnetic resonance imaging (MRI) approach for simultaneous in-depth analysis of valvular, myocardial as well as aortic morphology/pathophysiology to identify early changes in tissue texture and critical transition points in the adaptive process to AS. AS was induced by wire injury of the aortic valve. Four weeks after surgery, cine loops, velocity, and relaxometry maps were acquired at 9.4 T to monitor structural/functional alterations in valve, aorta, and left ventricle (LV). In vivo MRI data were subsequently validated by histology and compared to echocardiography. AS mice exhibited impaired valve opening accompanied by significant valve thickening due to fibrotic remodelling. While control mice showed bell-shaped flow profiles, AS resulted not only in higher peak flow velocities, but also in fragmented turbulent flow patterns associated with enhanced circumferential strain and an increase in wall thickness of the aortic root. AS mice presented with a mild hypertrophy but unaffected global LV function. Cardiac MR relaxometry revealed reduced values for both T1 and T2 in AS reflecting subtle myocardial tissue remodelling with early alterations in mitochondrial function in response to the enhanced afterload. Concomitantly, incipient impairments of coronary flow reserve and myocardial tissue integrity get apparent accompanied by early troponin release. With this, we identified a premature transition point with still compensated cardiac function but beginning textural changes. This will allow interventional studies to explore early disease pathophysiology and novel therapeutic targets.
Collapse
|
5
|
Ku MC, Kober F, Lai YC, Pohlmann A, Qadri F, Bader M, Carrier L, Niendorf T. Cardiovascular magnetic resonance detects microvascular dysfunction in a mouse model of hypertrophic cardiomyopathy. J Cardiovasc Magn Reson 2021; 23:63. [PMID: 34053450 PMCID: PMC8166121 DOI: 10.1186/s12968-021-00754-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 04/06/2021] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Hypertrophic cardiomyopathy (HCM) related myocardial vascular remodelling may lead to the reduction of myocardial blood supply and a subsequent progressive loss of cardiac function. This process has been difficult to observe and thus their connection remains unclear. Here we used non-invasive myocardial blood flow sensitive CMR to show an impairment of resting myocardial perfusion in a mouse model of naturally occurring HCM. METHODS We used a mouse model (DBA/2 J; D2 mouse strain) that spontaneously carries variants in the two most susceptible HCM genes-Mybpc3 and Myh7 and bears the key features of human HCM. The C57BL/6 J (B6) was used as a reference strain. Mice with either B6 or D2 backgrounds (male: n = 4, female: n = 4) underwent cine-CMR for functional assessment at 9.4 T. Left ventricular (LV) wall thickness was measured in end diastolic phase by cine-CMR. Quantitative myocardial perfusion maps (male: n = 5, female: n = 5 in each group) were acquired from arterial spin labelling (cine ASL-CMR) at rest. Myocardial perfusion values were measured by delineating different regions of interest based on the LV segmentation model in the mid ventricle of the LV myocardium. Directly after the CMR, the mouse hearts were removed for histological assessments to confirm the incidence of myocardial interstitial fibrosis (n = 8 in each group) and small vessel remodelling such as vessel density (n = 6 in each group) and perivascular fibrosis (n = 8 in each group). RESULTS LV hypertrophy was more pronounced in D2 than in B6 mice (male: D2 LV wall thickness = 1.3 ± 0.1 mm vs B6 LV wall thickness = 1.0 ± 0.0 mm, p < 0.001; female: D2 LV wall thickness = 1.0 ± 0.1 mm vs B6 LV wall thickness = 0.8 ± 0.1 mm, p < 0.01). The resting global myocardial perfusion (myocardial blood flow; MBF) was lower in D2 than in B6 mice (end-diastole: D2 MBFglobal = 7.5 ± 0.6 vs B6 MBFglobal = 9.3 ± 1.6 ml/g/min, p < 0.05; end-systole: D2 MBFglobal = 6.6 ± 0.8 vs B6 MBFglobal = 8.2 ± 2.6 ml/g/min, p < 0.01). This myocardial microvascular dysfunction was observed and associated with a reduction in regional MBF, mainly in the interventricular septal and inferior areas of the myocardium. Immunofluorescence revealed a lower number of vessel densities in D2 than in B6 (D2 capillary = 31.0 ± 3.8% vs B6 capillary = 40.7 ± 4.6%, p < 0.05). Myocardial collagen volume fraction (CVF) was significantly higher in D2 LV versus B6 LV mice (D2 CVF = 3.7 ± 1.4% vs B6 CVF = 1.7 ± 0.7%, p < 0.01). Furthermore, a higher ratio of perivascular fibrosis (PFR) was found in D2 than in B6 mice (D2 PFR = 2.3 ± 1.0%, B6 PFR = 0.8 ± 0.4%, p < 0.01). CONCLUSIONS Our work describes an imaging marker using cine ASL-CMR with a potential to monitor vascular and myocardial remodelling in HCM.
Collapse
Affiliation(s)
- Min-Chi Ku
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Robert-Rössle Strasse 10, 13125, Berlin, Germany.
- DZHK (German Centre for Cardiovascular Research), Partner site Berlin, Berlin, Germany.
| | - Frank Kober
- Centre de Résonance Magnétique Biologique et Médicale (CRMBM), Aix-Marseille University, CNRS, Marseille, France
| | - Yi-Ching Lai
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Robert-Rössle Strasse 10, 13125, Berlin, Germany
| | - Andreas Pohlmann
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Robert-Rössle Strasse 10, 13125, Berlin, Germany
| | - Fatimunnisa Qadri
- Molecular Biology of Peptide Hormones, Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Michael Bader
- DZHK (German Centre for Cardiovascular Research), Partner site Berlin, Berlin, Germany
- Molecular Biology of Peptide Hormones, Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Lucie Carrier
- Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), Partner site Hamburg/Kiel/Lübeck, Berlin, Germany
| | - Thoralf Niendorf
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Robert-Rössle Strasse 10, 13125, Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), Partner site Berlin, Berlin, Germany
- Experimental and Clinical Research Center (ECRC), A Joint Cooperation between the Charité Medical Faculty and the Max-Delbrück Center for Molecular Medicine, Berlin, Germany
| |
Collapse
|
6
|
Abstract
BACKGROUND Adenosine stress T1 mapping is an emerging magnetic resonance imaging method to investigate coronary vascular function and myocardial ischemia without application of a contrast agent. Using gene-modified mice and 2 vasodilators, we elucidated and compared the mechanisms of adenosine myocardial perfusion imaging and adenosine T1 mapping. METHODS Wild-type (WT), A2AAR-/- (adenosine A2A receptor knockout), A2BAR-/- (adenosine A2B receptor knockout), A3AR-/- (adenosine A3 receptor knockout), and eNOS-/- (endothelial nitric oxide synthase knockout) mice underwent rest and stress perfusion magnetic resonance imaging (n=8) and T1 mapping (n=10) using either adenosine, regadenoson (a selective A2AAR agonist), or saline. Myocardial blood flow and T1 were computed from perfusion imaging and T1 mapping, respectively, at rest and stress to assess myocardial perfusion reserve and T1 reactivity (ΔT1). Changes in heart rate for each stress agent were also calculated. Two-way ANOVA was used to detect differences in each parameter between the different groups of mice. RESULTS Myocardial perfusion reserve was significantly reduced only in A2AAR-/- compared to WT mice using adenosine (1.06±0.16 versus 2.03±0.52, P<0.05) and regadenoson (0.98±026 versus 2.13±0.75, P<0.05). In contrast, adenosine ΔT1 was reduced compared with WT mice (3.88±1.58) in both A2AAR-/- (1.63±1.32, P<0.05) and A2BAR-/- (1.55±1.35, P<0.05). Furthermore, adenosine ΔT1 was halved in eNOS-/- (1.76±1.46, P<0.05) versus WT mice. Regadenoson ΔT1 was approximately half of adenosine ΔT1 in WT mice (1.97±1.50, P<0.05), and additionally, it was significantly reduced in eNOS-/- mice (-0.22±1.46, P<0.05). Lastly, changes in heart rate was 2× greater using regadenoson versus adenosine in all groups except A2AAR-/-, where heart rate remained constant. CONCLUSIONS The major findings are that (1) although adenosine myocardial perfusion reserve is mediated through the A2A receptor, adenosine ΔT1 is mediated through the A2A and A2B receptors, (2) adenosine myocardial perfusion reserve is endothelial independent while adenosine ΔT1 is partially endothelial dependent, and (3) ΔT1 mediated through the A2A receptor is endothelial dependent while ΔT1 mediated through the A2B receptor is endothelial independent.
Collapse
Affiliation(s)
- Soham A Shah
- Department of Biomedical Engineering (S.A.S., C.E.R., B.A.F., F.H.E.), University of Virginia, Charlottesville, VA
| | - Claire E Reagan
- Department of Radiology (B.A.F., F.H.E.), University of Virginia, Charlottesville, VA
| | - Brent A French
- Department of Biomedical Engineering (S.A.S., C.E.R., B.A.F., F.H.E.), University of Virginia, Charlottesville, VA.,Department of Radiology (B.A.F., F.H.E.), University of Virginia, Charlottesville, VA.,The Robert M. Berne Cardiovascular Research Center (B.A.F., F.H.E.), University of Virginia, Charlottesville, VA
| | - Frederick H Epstein
- Department of Biomedical Engineering (S.A.S., C.E.R., B.A.F., F.H.E.), University of Virginia, Charlottesville, VA.,Department of Radiology (B.A.F., F.H.E.), University of Virginia, Charlottesville, VA.,The Robert M. Berne Cardiovascular Research Center (B.A.F., F.H.E.), University of Virginia, Charlottesville, VA
| |
Collapse
|
7
|
Lee NG, Javed A, Jao TR, Nayak KS. Numerical approximation to the general kinetic model for ASL quantification. Magn Reson Med 2020; 84:2846-2857. [PMID: 32367574 DOI: 10.1002/mrm.28304] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/19/2020] [Accepted: 04/08/2020] [Indexed: 12/21/2022]
Abstract
PURPOSE To develop a numerical approximation to the general kinetic model for arterial spin labeling (ASL) quantification that will enable greater flexibility in ASL acquisition methods. THEORY The Bloch-McConnell equations are extended to include the effects of single-compartment inflow and outflow on both the transverse and longitudinal magnetization. These can be solved using an extension of Jaynes' matrix formalism with piecewise constant approximation of incoming labeled arterial flow and a clearance operator for outgoing venous flow. METHODS The proposed numerical approximation is compared with the general kinetic model using simulations of pulsed labeling and pseudo-continuous labeling and a broad range of transit time and bolus duration for tissue blood flow of 0.6 mL/g/min. Accuracy of the approximation is studied as a function of the timestep using Monte-Carlo simulations. Three additional scenarios are demonstrated: (1) steady-pulsed ASL, (2) MR fingerprinting ASL, and (3) balanced SSFP and spoiled gradient-echo sequences. RESULTS The proposed approximation was found to be arbitrarily accurate for pulsed labeling and pseudo-continuous labeling. The pulsed labeling/pseudo-continuous labeling approximation error compared with the general kinetic model was less than 0.002% (<0.002%) and less than 0.05% (<0.05%) for timesteps of 3 ms and 35 ms, respectively. The proposed approximation matched well with customized signal expressions of steady-pulsed ASL and MR fingerprinting ASL. The simulations of simultaneous modeling of flow, T2 , and magnetization transfer showed an increase in steady-state balanced SSFP and spoiled gradient signals. CONCLUSION We demonstrate a numerical approximation of the "Bloch-McConnell flow" equations that enables arbitrarily accurate modeling of pulsed ASL and pseudo-continuous labeling signals comparable to the general kinetic model. This enables increased flexibility in the experiment design for quantitative ASL.
Collapse
Affiliation(s)
- Nam G Lee
- Department of Biomedical Engineering, University of Southern California, Los Angeles, California, USA
| | - Ahsan Javed
- Ming Hsieh Department of Electrical and Computer Engineering, University of Southern California, Los Angeles, California, USA
| | - Terrence R Jao
- Department of Biomedical Engineering, University of Southern California, Los Angeles, California, USA
| | - Krishna S Nayak
- Ming Hsieh Department of Electrical and Computer Engineering, University of Southern California, Los Angeles, California, USA
| |
Collapse
|
8
|
Gottschalk M. Look-Locker FAIR TrueFISP for arterial spin labelling on mouse at 9.4 T. NMR IN BIOMEDICINE 2020; 33:e4191. [PMID: 31829485 DOI: 10.1002/nbm.4191] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 08/21/2019] [Accepted: 08/29/2019] [Indexed: 06/10/2023]
Abstract
Pulsed arterial spin labelling remains a non-invasive and highly used method for the study of rodent cerebral blood flow (CBF). Flow-sensitive alternating inversion recovery (FAIR) is one of the most commonly used MR-sequences for this purpose and exists with many different strategies to record the images. This study investigates Look-Locker (LL) TrueFISP readout for FAIR as an alternative to the standard EPI readout, which is provided by the manufacturer. The aim was to show the improved image quality using TrueFISP and to verify the reproducibility of the determination of the cerebral blood flow values. The measurement of many inversion points also allowed to investigate the influence of the correct blood relaxation rate on the fit of the CBF data. For the LL-FAIR TrueFISP an in-house written method was created. The method was tested on a group of C57BL/6 mice at the field strength of 9.4 T. The results show CBF maps with less distortion than for EPI and the values found are in good agreement with the literature. A comparison of the CBF values found with EPI and LL-TrueFISP shows very small differences, most being not significant. In conclusion, the method presented gives equivalent CBF maps in comparison to standard FAIR-EPI. Both methods have the same measurement time. TrueFISP has the advantage to EPI of producing undistorted images over larger areas of the mouse brain. It is advisable to check the value of the blood relaxation rate by measurement or to estimate it as a fitting parameter.
Collapse
|
9
|
Changes in cell fate determine the regenerative and functional capacity of the developing kidney before and after release of obstruction. Clin Sci (Lond) 2018; 132:2519-2545. [PMID: 30442812 DOI: 10.1042/cs20180623] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 10/23/2018] [Accepted: 11/14/2018] [Indexed: 12/14/2022]
Abstract
Congenital obstructive nephropathy is a major cause of chronic kidney disease (CKD) in children. The contribution of changes in the identity of renal cells to the pathology of obstructive nephropathy is poorly understood. Using a partial unilateral ureteral obstruction (pUUO) model in genetically modified neonatal mice, we traced the fate of cells derived from the renal stroma, cap mesenchyme, ureteric bud (UB) epithelium, and podocytes using Foxd1Cre, Six2Cre, HoxB7Cre, and Podocyte.Cre mice respectively, crossed with double fluorescent reporter (membrane-targetted tandem dimer Tomato (mT)/membrane-targetted GFP (mG)) mice. Persistent obstruction leads to a significant loss of tubular epithelium, rarefaction of the renal vasculature, and decreased renal blood flow (RBF). In addition, Forkhead Box D1 (Foxd1)-derived pericytes significantly expanded in the interstitial space, acquiring a myofibroblast phenotype. Degeneration of Sine Oculis Homeobox Homolog 2 (Six2) and HoxB7-derived cells resulted in significant loss of glomeruli, nephron tubules, and collecting ducts. Surgical release of obstruction resulted in striking regeneration of tubules, arterioles, interstitium accompanied by an increase in blood flow to the level of sham animals. Contralateral kidneys with remarkable compensatory response to kidney injury showed an increase in density of arteriolar branches. Deciphering the mechanisms involved in kidney repair and regeneration post relief of obstruction has potential therapeutic implications for infants and children and the growing number of adults suffering from CKD.
Collapse
|
10
|
Knutsson L, Xu J, Ahlgren A, van Zijl P. CEST, ASL, and magnetization transfer contrast: How similar pulse sequences detect different phenomena. Magn Reson Med 2018; 80:1320-1340. [PMID: 29845640 PMCID: PMC6097930 DOI: 10.1002/mrm.27341] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 04/10/2018] [Accepted: 04/11/2018] [Indexed: 12/28/2022]
Abstract
Chemical exchange saturation transfer (CEST), arterial spin labeling (ASL), and magnetization transfer contrast (MTC) methods generate different contrasts for MRI. However, they share many similarities in terms of pulse sequences and mechanistic principles. They all use RF pulse preparation schemes to label the longitudinal magnetization of certain proton pools and follow the delivery and transfer of this magnetic label to a water proton pool in a tissue region of interest, where it accumulates and can be detected using any imaging sequence. Due to the versatility of MRI, differences in spectral, spatial or motional selectivity of these schemes can be exploited to achieve pool specificity, such as for arterial water protons in ASL, protons on solute molecules in CEST, and protons on semi-solid cell structures in MTC. Timing of these sequences can be used to optimize for the rate of a particular delivery and/or exchange transfer process, for instance, between different tissue compartments (ASL) or between tissue molecules (CEST/MTC). In this review, magnetic labeling strategies for ASL and the corresponding CEST and MTC pulse sequences are compared, including continuous labeling, single-pulse labeling, and multi-pulse labeling. Insight into the similarities and differences among these techniques is important not only to comprehend the mechanisms and confounds of the contrasts they generate, but also to stimulate the development of new MRI techniques to improve these contrasts or to reduce their interference. This, in turn, should benefit many possible applications in the fields of physiological and molecular imaging and spectroscopy.
Collapse
Affiliation(s)
- L Knutsson
- Department of Medical Radiation Physics, Lund University, Lund, Sweden
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - J Xu
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, United States
| | - A Ahlgren
- Department of Medical Radiation Physics, Lund University, Lund, Sweden
| | - P.C.M van Zijl
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, United States
| |
Collapse
|
11
|
Yoon AJ, Do HP, Cen S, Fong MW, Saremi F, Barr ML, Nayak KS. Assessment of segmental myocardial blood flow and myocardial perfusion reserve by adenosine-stress myocardial arterial spin labeling perfusion imaging. J Magn Reson Imaging 2017; 46:413-420. [DOI: 10.1002/jmri.25604] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 12/05/2016] [Indexed: 01/19/2023] Open
Affiliation(s)
- Andrew J. Yoon
- Department of Medicine, Division of Cardiology, Keck School of Medicine of USC; University of Southern California; Los Angeles California USA
| | - Hung Phi Do
- Department of Physics and Astronomy; University of Southern California; Los Angeles California USA
| | - Steven Cen
- Department of Radiology, Keck School of Medicine of USC; University of Southern California; Los Angeles California USA
| | - Michael W. Fong
- Department of Medicine, Division of Cardiology, Keck School of Medicine of USC; University of Southern California; Los Angeles California USA
| | - Farhood Saremi
- Department of Radiology, Keck School of Medicine of USC; University of Southern California; Los Angeles California USA
| | - Mark L. Barr
- Department of Cardiothoracic Surgery, Keck School of Medicine of USC; University of Southern California; Los Angeles California USA
| | - Krishna S. Nayak
- Ming Hsieh Department of Electrical Engineering; University of Southern California; Los Angeles California USA
| |
Collapse
|
12
|
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
|
13
|
Kober F, Jao T, Troalen T, Nayak KS. Myocardial arterial spin labeling. J Cardiovasc Magn Reson 2016; 18:22. [PMID: 27071861 PMCID: PMC4830031 DOI: 10.1186/s12968-016-0235-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/22/2016] [Indexed: 11/10/2022] Open
Abstract
Arterial spin labeling (ASL) is a cardiovascular magnetic resonance (CMR) technique for mapping regional myocardial blood flow. It does not require any contrast agents, is compatible with stress testing, and can be performed repeatedly or even continuously. ASL-CMR has been performed with great success in small-animals, but sensitivity to date has been poor in large animals and humans and remains an active area of research. This review paper summarizes the development of ASL-CMR techniques, current state-of-the-art imaging methods, the latest findings from pre-clinical and clinical studies, and future directions. We also explain how successful developments in brain ASL and small-animal ASL-CMR have helped to inform developments in large animal and human ASL-CMR.
Collapse
Affiliation(s)
- Frank Kober
- />Aix-Marseille Université, CNRS CRMBM UMR 7339, Centre de Résonance Magnétique Biologique et Médicale, Marseille, France
| | - Terrence Jao
- />Department of Biomedical Engineering, University of Southern California, Los Angeles, California USA
| | - Thomas Troalen
- />Aix-Marseille Université, CNRS CRMBM UMR 7339, Centre de Résonance Magnétique Biologique et Médicale, Marseille, France
| | - Krishna S. Nayak
- />Department of Biomedical Engineering, University of Southern California, Los Angeles, California USA
- />Ming Hsieh Department of Electrical Engineering, University of Southern California, Los Angeles, California USA
| |
Collapse
|
14
|
Abdesselam I, Pepino P, Troalen T, Macia M, Ancel P, Masi B, Fourny N, Gaborit B, Giannesini B, Kober F, Dutour A, Bernard M. Time course of cardiometabolic alterations in a high fat high sucrose diet mice model and improvement after GLP-1 analog treatment using multimodal cardiovascular magnetic resonance. J Cardiovasc Magn Reson 2015; 17:95. [PMID: 26546347 PMCID: PMC4636800 DOI: 10.1186/s12968-015-0198-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 10/28/2015] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Cardiovascular complications of obesity and diabetes are major health problems. Assessing their development, their link with ectopic fat deposition and their flexibility with therapeutic intervention is essential. The aim of this study was to longitudinally investigate cardiac alterations and ectopic fat accumulation associated with diet-induced obesity using multimodal cardiovascular magnetic resonance (CMR) in mice. The second objective was to monitor cardiac response to exendin-4 (GLP-1 receptor agonist). METHODS Male C57BL6R mice subjected to a high fat (35 %) high sucrose (34 %) (HFHSD) or a standard diet (SD) during 4 months were explored every month with multimodal CMR to determine hepatic and myocardial triglyceride content (HTGC, MTGC) using proton MR spectroscopy, cardiac function with cine cardiac MR (CMR) and myocardial perfusion with arterial spin labeling CMR. Furthermore, mice treated with exendin-4 (30 μg/kg SC BID) after 4 months of diet were explored before and 14 days post-treatment with multimodal CMR. RESULTS HFHSD mice became significantly heavier (+33 %) and displayed glucose homeostasis impairment (1-month) as compared to SD mice, and developed early increase in HTGC (1 month, +59 %) and MTGC (2-month, +63 %). After 3 months, HFHSD mice developed cardiac dysfunction with significantly higher diastolic septum wall thickness (sWtnD) (1.28 ± 0.03 mm vs. 1.12 ± 0.03 mm) and lower cardiac index (0.45 ± 0.06 mL/min/g vs. 0.68 ± 0.07 mL/min/g, p = 0.02) compared to SD mice. A significantly lower cardiac perfusion was also observed (4 months:7.5 ± 0.8 mL/g/min vs. 10.0 ± 0.7 mL/g/min, p = 0.03). Cardiac function at 4 months was negatively correlated to both HTGC and MTGC (p < 0.05). 14-day treatment with Exendin-4 (Ex-4) dramatically reversed all these alterations in comparison with placebo-treated HFHSD. Ex-4 diminished myocardial triglyceride content (-57.8 ± 4.1 %), improved cardiac index (+38.9 ± 10.9 %) and restored myocardial perfusion (+52.8 ± 16.4 %) under isoflurane anesthesia. Interestingly, increased wall thickness and hepatic steatosis reductions were independent of weight loss and glycemia decrease in multivariate analysis (p < 0.05). CONCLUSION CMR longitudinal follow-up of cardiac consequences of obesity and diabetes showed early accumulation of ectopic fat in mice before the occurrence of microvascular and contractile dysfunction. This study also supports a cardioprotective effect of glucagon-like peptide-1 receptor agonist.
Collapse
Affiliation(s)
- Inès Abdesselam
- Aix-Marseille Université, CNRS, CRMBM, UMR7339, 27, Bd Jean Moulin, 13385, Marseille, France
- Aix-Marseille Université, NORT, Inserm U1062/Inra1260, 13385, Marseille, France
| | - Pauline Pepino
- Aix-Marseille Université, CNRS, CRMBM, UMR7339, 27, Bd Jean Moulin, 13385, Marseille, France
| | - Thomas Troalen
- Aix-Marseille Université, CNRS, CRMBM, UMR7339, 27, Bd Jean Moulin, 13385, Marseille, France
| | - Michael Macia
- Aix-Marseille Université, CNRS, CRMBM, UMR7339, 27, Bd Jean Moulin, 13385, Marseille, France
| | - Patricia Ancel
- Aix-Marseille Université, NORT, Inserm U1062/Inra1260, 13385, Marseille, France
| | - Brice Masi
- Aix-Marseille Université, CNRS, CRMBM, UMR7339, 27, Bd Jean Moulin, 13385, Marseille, France
| | - Natacha Fourny
- Aix-Marseille Université, CNRS, CRMBM, UMR7339, 27, Bd Jean Moulin, 13385, Marseille, France
| | - Bénédicte Gaborit
- Aix-Marseille Université, NORT, Inserm U1062/Inra1260, 13385, Marseille, France
- Endocrinology, Metabolic diseases and nutrition, CHU Nord, Marseille, France
| | - Benoît Giannesini
- Aix-Marseille Université, CNRS, CRMBM, UMR7339, 27, Bd Jean Moulin, 13385, Marseille, France
| | - Frank Kober
- Aix-Marseille Université, CNRS, CRMBM, UMR7339, 27, Bd Jean Moulin, 13385, Marseille, France
| | - Anne Dutour
- Aix-Marseille Université, NORT, Inserm U1062/Inra1260, 13385, Marseille, France
- Endocrinology, Metabolic diseases and nutrition, CHU Nord, Marseille, France
| | - Monique Bernard
- Aix-Marseille Université, CNRS, CRMBM, UMR7339, 27, Bd Jean Moulin, 13385, Marseille, France.
| |
Collapse
|
15
|
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
|
16
|
Naresh NK, Chen X, Moran E, Tian Y, French BA, Epstein FH. Repeatability and variability of myocardial perfusion imaging techniques in mice: Comparison of arterial spin labeling and first-pass contrast-enhanced MRI. Magn Reson Med 2015; 75:2394-405. [PMID: 26190350 DOI: 10.1002/mrm.25769] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 04/14/2015] [Accepted: 04/20/2015] [Indexed: 11/08/2022]
Abstract
PURPOSE Preclinical imaging of myocardial blood flow (MBF) can elucidate molecular mechanisms underlying cardiovascular disease. We compared the repeatability and variability of two methods, first-pass MRI and arterial spin labeling (ASL), for imaging MBF in mice. METHODS Quantitative perfusion MRI in mice was performed using both methods at rest, with a vasodilator, and one day after myocardial infarction. Image quality (score of 1-5; 5 best), between-session coefficient of variability (CVbs ), intra-user coefficient of variability (CVintra-user ), and inter-user coefficient of variability (CVinter-user ) were assessed. Acquisition time was 1-2 min for first-pass MRI and approximately 40 min for ASL. RESULTS Image quality was higher for ASL (3.94 ± 0.09 versus 2.88 ± 0.10; P < 0.05). Infarct zone CVbs was lower with first-pass (17 ± 3% versus 46 ± 9%; P < 0.05). The stress perfusion CVintra-user was lower for ASL (3 ± 1% versus 14 ± 3%; P < 0.05). The stress perfusion CVinter-user was lower for ASL (4 ± 1% versus 17 ± 4%; P < 0.05). CONCLUSION For low MBF conditions such as infarct, first-pass MRI is preferred due to better repeatability and variability. At high MBF such as at vasodilation, ASL may be more suitable due to superior image quality and lower user variability. First-pass MRI has a substantial speed advantage. Magn Reson Med 75:2394-2405, 2016. © 2015 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Nivedita K Naresh
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
| | - Xiao Chen
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
| | - Eric Moran
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
| | - Yikui Tian
- Department of Surgery, University of Virginia, Charlottesville, Virginia, USA
| | - Brent A French
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
| | - Frederick H Epstein
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA.,Department of Radiology, University of Virginia, Charlottesville, Virginia, USA
| |
Collapse
|
17
|
Xu J, Qin Q, Wu D, Hua J, Song X, McMahon MT, Northington FJ, Zhang J, van Zijl PCM, Pekar JJ. Steady pulsed imaging and labeling scheme for noninvasive perfusion imaging. Magn Reson Med 2015; 75:238-48. [PMID: 25732958 DOI: 10.1002/mrm.25641] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 01/05/2015] [Accepted: 01/07/2015] [Indexed: 02/06/2023]
Abstract
PURPOSE A steady pulsed imaging and labeling (SPIL) scheme is proposed to obtain high-resolution multislice perfusion images of mice brain using standard preclinical MRI equipment. THEORY AND METHODS The SPIL scheme repeats a pulsed arterial spin labeling (PASL) module together with a short mixing time to extend the temporal duration of the generated PASL bolus to the total experimental time. Multislice image acquisition takes place during the mixing times. The mixing time is also used for magnetization recovery following image acquisition. The new scheme is able to yield multislice perfusion images rapidly. The perfusion kinetic curve can be measured by a multipulsed imaging and labeling (MPIL) scheme, i.e., acquiring single-slice ASL signals before reaching steady-state in the SPIL sequence. RESULTS When applying the SPIL method to normal mice, and to mice with unilateral ischemia, high-resolution multislice (five slices) CBF images could be obtained in 8 min. Perfusion data from ischemic mice showed clear CBF reductions in ischemic regions. The SPIL method was also applied to postmortem mice, showing that the method is free from magnetization transfer confounds. CONCLUSION The new SPIL scheme provides for robust measurement of CBF with multislice imaging capability in small animals.
Collapse
Affiliation(s)
- Jiadi Xu
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - Qin Qin
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - Dan Wu
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jun Hua
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - Xiaolei Song
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Michael T McMahon
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - Frances J Northington
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jiangyang Zhang
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Peter C M van Zijl
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - James J Pekar
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
| |
Collapse
|
18
|
Gutjahr FT, Kampf T, Winter P, Meyer CB, Williams T, Jakob PM, Bauer WR, Ziener CH, Helluy X. Quantification of perfusion in murine myocardium: A retrospectively triggered T1 -based ASL method using model-based reconstruction. Magn Reson Med 2014; 74:1705-15. [PMID: 25446550 DOI: 10.1002/mrm.25526] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 10/06/2014] [Accepted: 10/20/2014] [Indexed: 11/12/2022]
Abstract
PURPOSE A method for the quantification of perfusion in murine myocardium is demonstrated. The method allows for the reconstruction of perfusion maps on arbitrary time points in the heart cycle while addressing problems that arise due to the irregular heart beat of mice. METHODS A flow-sensitive alternating inversion recovery arterial spin labeling method using an untriggered FLASH-read out with random sampling is used. Look-Locker conditions are strictly maintained. No dummy pulses or mechanism to reduce deviation from Look-Locker conditions are needed. Electrocardiogram and respiratory data are recorded for retrospective gating and triggering. A model-based technique is used to reconstruct missing k-space data to cope with the undersampling inherent in retrospectively gated methods. Acquisition and reconstruction were validated numerically and in phantom measurements before in vivo experimentation. RESULTS Quantitative perfusion maps were acquired within a single slice measurement time of 11 min. Perfusion values are in good accordance to literature values. Myocardial infarction could be clearly visualized and results were confirmed with histological results. CONCLUSION The proposed method is capable of producing quantitative perfusion maps on arbitrary positions in the heart cycle within a short measurement time. The method is robust against irregular breathing patterns and heart rate changes and can be implemented on all scanners.
Collapse
Affiliation(s)
- Fabian T Gutjahr
- Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, 97074, Würzburg, Germany.,Comprehensive Heart Failure Center, Core Facility Imaging, Straubmühlweg 2a, 97078, Würzburg, Germany
| | - Thomas Kampf
- Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, 97074, Würzburg, Germany
| | - Patrick Winter
- Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, 97074, Würzburg, Germany
| | - Cord B Meyer
- Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, 97074, Würzburg, Germany
| | - Tatjana Williams
- Universität Würzburg, Medizinische Klinik und Poliklinik I, Oberdürrbacher Straße 6, 97080, Würzburg, Germany
| | - Peter M Jakob
- Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, 97074, Würzburg, Germany
| | - Wolfgang R Bauer
- Universität Würzburg, Medizinische Klinik und Poliklinik I, Oberdürrbacher Straße 6, 97080, Würzburg, Germany
| | - Christian H Ziener
- German Cancer Research Center DKFZ, Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - Xavier Helluy
- Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, 97074, Würzburg, Germany
| |
Collapse
|
19
|
Capron T, Troalen T, Robert B, Jacquier A, Bernard M, Kober F. Myocardial perfusion assessment in humans using steady-pulsed arterial spin labeling. Magn Reson Med 2014; 74:990-8. [DOI: 10.1002/mrm.25479] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 09/04/2014] [Accepted: 09/07/2014] [Indexed: 11/08/2022]
Affiliation(s)
- Thibaut Capron
- Aix-Marseille Université, UMR 7339, CNRS, CRMBM (Centre de Résonance Magnétique Biologique et Médicale); 13385 Marseille France
| | - Thomas Troalen
- Aix-Marseille Université, UMR 7339, CNRS, CRMBM (Centre de Résonance Magnétique Biologique et Médicale); 13385 Marseille France
| | | | - Alexis Jacquier
- Aix-Marseille Université, UMR 7339, CNRS, CRMBM (Centre de Résonance Magnétique Biologique et Médicale); 13385 Marseille France
| | - Monique Bernard
- Aix-Marseille Université, UMR 7339, CNRS, CRMBM (Centre de Résonance Magnétique Biologique et Médicale); 13385 Marseille France
| | - Frank Kober
- Aix-Marseille Université, UMR 7339, CNRS, CRMBM (Centre de Résonance Magnétique Biologique et Médicale); 13385 Marseille France
| |
Collapse
|
20
|
Desrois M, Kober F, Lan C, Dalmasso C, Cole M, Clarke K, Cozzone PJ, Bernard M. Effect of isoproterenol on myocardial perfusion, function, energy metabolism and nitric oxide pathway in the rat heart - a longitudinal MR study. NMR IN BIOMEDICINE 2014; 27:529-538. [PMID: 24677605 DOI: 10.1002/nbm.3088] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 01/06/2014] [Accepted: 01/09/2014] [Indexed: 06/03/2023]
Abstract
The chronic administration of the β-adrenoreceptor agonist isoproterenol (IsoP) is used in animals to study the mechanisms of cardiac hypertrophy and failure associated with a sustained increase in circulating catecholamines. Time-dependent changes in myocardial blood flow (MBF), morphological and functional parameters were assessed in rats in vivo using multimodal cardiac MRI. Energy metabolism, oxidative stress and the nitric oxide (NO) pathway were evaluated in isolated perfused rat hearts following 7 days of treatment. Male Wistar rats were infused for 7 days with IsoP or vehicle using osmotic pumps. Cine-MRI and arterial spin labeling were used to determine left ventricular morphology, function and MBF at days 1, 2 and 7 after pump implantation. Isolated hearts were then perfused, and high-energy phosphate compounds and intracellular pH were followed using ³¹P MRS with simultaneous measurement of contractile function. Total creatine and malondialdehyde (MDA) contents were measured by high-performance liquid chromatography. The NO pathway was evaluated by NO synthase isoform expression and total nitrate concentration (NO(x)). In IsoP-treated rats, left ventricular mass was increased at day 1 and maintained. Wall thickness was increased with a peak at day 2 and a tendency to return to baseline values at day 7. MBF was markedly increased at day 1 and returned to normal values between days 1 and 2. The rate-pressure product and phosphocreatine/adenosine triphosphate ratio in perfused hearts were reduced. MDA, endothelial NO synthase expression and NO(x) were increased. Sustained high cardiac function and normal MBF after 24 h of IsoP infusion indicate imbalance between functional demand and blood flow, leading to morphological changes. After 1 week, cardiac hypertrophy and decreased function were associated with impaired phosphocreatine, increased oxidative stress and up-regulation of the NO pathway. These results provide supplemental information on the evolution of the different contributing factors leading to morphological and functional changes in this model of cardiac hypertrophy and failure.
Collapse
Affiliation(s)
- Martine Desrois
- Aix-Marseille Université UMR CNRS n°7339, Centre de Résonance Magnétique Biologique et Médicale (CRMBM), Faculté de Médecine, Marseille, France
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Naresh NK, Chen X, Roy RJ, Antkowiak PF, Annex BH, Epstein FH. Accelerated dual-contrast first-pass perfusion MRI of the mouse heart: development and application to diet-induced obese mice. Magn Reson Med 2014; 73:1237-45. [PMID: 24760707 DOI: 10.1002/mrm.25238] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 02/19/2014] [Accepted: 03/11/2014] [Indexed: 12/23/2022]
Abstract
PURPOSE Gene-modified mice may be used to elucidate molecular mechanisms underlying abnormal myocardial blow flow (MBF). We sought to develop a quantitative myocardial perfusion imaging technique for mice and to test the hypothesis that myocardial perfusion reserve (MPR) is reduced in a mouse model of diet-induced obesity (DIO). METHODS A dual-contrast saturation-recovery sequence with ky -t undersampling and a motion-compensated compressed sensing reconstruction algorithm was developed for first-pass MRI on a small-bore 7 Tesla system. Control mice were imaged at rest and with the vasodilators ATL313 and Regadenoson (n = 6 each). In addition, we imaged mice fed a high-fat diet (HFD) for 24 weeks. RESULTS In control mice, MBF was 5.7 ± 0.8 mL/g/min at rest and it increased to 11.8 ± 0.6 mL/g/min with ATL313 and to 10.4 ± 0.3 mL/g/min with Regadenoson. In HFD mice, we detected normal resting MBF (5.6 ± 0.4 versus 5.0 ± 0.3 on control diet), low MBF at stress (7.7 ± 0.4 versus 10.4 ± 0.3 on control diet, P < 0.05), and reduced MPR (1.4 ± 0.2 versus 2.0 ± 0.3 on control diet, P < 0.05). CONCLUSION Accelerated dual-contrast first-pass MRI with motion-compensated compressed sensing provides spatiotemporal resolution suitable for measuring MBF in free-breathing mice, and detected reduced MPR in DIO mice. These techniques may be used to study molecular mechanisms that underlie abnormal myocardial perfusion.
Collapse
Affiliation(s)
- Nivedita K Naresh
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
| | | | | | | | | | | |
Collapse
|
22
|
Troalen T, Capron T, Bernard M, Kober F. In vivo characterization of rodent cyclic myocardial perfusion variation at rest and during adenosine-induced stress using cine-ASL cardiovascular magnetic resonance. J Cardiovasc Magn Reson 2014; 16:18. [PMID: 24548535 PMCID: PMC3937054 DOI: 10.1186/1532-429x-16-18] [Citation(s) in RCA: 16] [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: 09/06/2013] [Accepted: 02/10/2014] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Assessment of cyclic myocardial blood flow (MBF) variations can be an interesting addition to the characterization of microvascular function and its alterations. To date, totally non-invasive in vivo methods with this capability are still lacking. As an original technique, a cine arterial spin labeling (ASL) cardiovascular magnetic resonance approach is demonstrated to be able to produce dynamic MBF maps across the cardiac cycle in rats. METHOD High-resolution MBF maps in left ventricular myocardium were computed from steady-state perfusion-dependent gradient-echo cine images produced by the cine-ASL sequence. Cyclic changes of MBF over the entire cardiac cycle in seven normal rats were analyzed quantitatively every 6 ms at rest and during adenosine-induced stress. RESULTS The study showed a significant MBF increase from end-systole (ES) to end-diastole (ED) in both physiological states. Mean MBF over the cardiac cycle within the group was 5.5 ± 0.6 mL g(-1) min(-1) at rest (MBFMin = 4.7 ± 0.8 at ES and MBFMax = 6.5 ± 0.6 mL g(-1) min(-1) at ED, P = 0.0007). Mean MBF during adenosine-induced stress was 12.8 ± 0.7mL g(-1) min(-1) (MBFMin = 11.7±1.0 at ES and MBFMax = 14.2 ± 0.7 mL g(-1) min(-1) at ED, P = 0.0007). MBF percentage relative variations were significantly different with 27.2 ± 9.3% at rest and 17.8 ± 7.1% during adenosine stress (P = 0.014). The dynamic analysis also showed a time shift of peak MBF within the cardiac cycle during stress. CONCLUSION The cyclic change of myocardial perfusion was examined by mapping MBF with a steady-pulsed ASL approach. Dynamic MBF maps were obtained with high spatial and temporal resolution (6 ms) demonstrating the feasibility of non-invasively mapping cyclic myocardial perfusion variation at rest and during adenosine stress. In a pathological context, detailed assessment of coronary responses to infused vasodilators may give valuable complementary information on microvascular functional defects in disease models.
Collapse
Affiliation(s)
- Thomas Troalen
- Aix-Marseille Université, CNRS, CRMBM UMR 7339, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| | - Thibaut Capron
- Aix-Marseille Université, CNRS, CRMBM UMR 7339, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| | - Monique Bernard
- Aix-Marseille Université, CNRS, CRMBM UMR 7339, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| | - Frank Kober
- Aix-Marseille Université, CNRS, CRMBM UMR 7339, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| |
Collapse
|
23
|
|