Diffusion Tensor Cardiovascular Magnetic Resonance Research Articles

Referenceless Nyquist ghost correction outperforms standard navigator-based method and improves efficiency of in vivo diffusion tensor cardiovascular magnetic resonance.

The study aims to assess the potential of referenceless methods of EPI ghost correction to accelerate the acquisition of in vivo diffusion tensor cardiovascular magnetic resonance (DT-CMR) data using both computational simulations and data from in vivo experiments. Three referenceless EPI ghost correction methods were evaluated on mid-ventricular short axis DT-CMR spin echo and STEAM datasets from 20 healthy subjects at 3T. The reduced field of view excitation technique was used to automatically quantify the Nyquist ghosts, and DT-CMR images were fit to a linear ghost model for correction. Numerical simulation showed the singular value decomposition (SVD) method is the least sensitive to noise, followed by Ghost/Object method and entropy-based method. In vivo experiments showed significant ghost reduction for all correction methods, with referenceless methods outperforming navigator methods for both spin echo and STEAM sequences at b = 32, 150, 450, and 600 . It is worth noting that as the strength of the diffusion encoding increases, the performance gap between the referenceless method and the navigator-based method diminishes. Referenceless ghost correction effectively reduces Nyquist ghost in DT-CMR data, showing promise for enhancing the accuracy and efficiency of measurements in clinical practice without the need for any additional reference scans.

Kiosk 10R-TA-06 - Early Assessment of Myocardial Microstructural Changes in Patients with Hypertrophic Cardiomyopathy by in Vivo Diffusion Tensor Cardiovascular Magnetic Resonance

Kiosk 10R-TA-06 - Early Assessment of Myocardial Microstructural Changes in Patients with Hypertrophic Cardiomyopathy by in Vivo Diffusion Tensor Cardiovascular Magnetic Resonance

Kiosk 10R-TA-02 - Cardiac Microstructure in Genotyped Hypertrophic and Dilated Cardiomyopathy Revealed by Diffusion Tensor Cardiovascular Magnetic Resonance

Kiosk 10R-TA-02 - Cardiac Microstructure in Genotyped Hypertrophic and Dilated Cardiomyopathy Revealed by Diffusion Tensor Cardiovascular Magnetic Resonance

Realistic numerical simulations of diffusion tensor cardiovascular magnetic resonance: The effects of perfusion and membrane permeability.

To study the sensitivity of diffusion tensor cardiovascular magnetic resonance (DT-CMR) to microvascular perfusion and changes in cell permeability. Monte Carlo (MC) random walk simulations in the myocardium have been performed to simulate self-diffusion of water molecules in histology-based media with varying extracellular volume fraction (ECV) and permeable membranes. The effect of microvascular perfusion on simulations of the DT-CMR signal has been incorporated by adding the contribution of particles traveling through an anisotropic capillary network to the diffusion signal. The simulations have been performed considering three pulse sequences with clinical gradient strengths: monopolar stimulated echo acquisition mode (STEAM), monopolar pulsed-gradient spin echo (PGSE), and second-order motion-compensated spin echo (MCSE). Reducing ECV intensifies the diffusion restriction and incorporating membrane permeability reduces the anisotropy of the diffusion tensor. Widening the intercapillary velocity distribution results in increased measured diffusion along the cardiomyocytes long axis when the capillary networks are anisotropic. Perfusion amplifies the mean diffusivity for STEAM while the opposite is observed for short diffusion encoding time sequences (PGSE and MCSE). The effect of perfusion on the measured diffusion tensor is reduced using an increased reference b-value. Our results pave the way for characterization of the response of DT-CMR to microstructural changes underlying cardiac pathology and highlight the higher sensitivity of STEAM to permeability and microvascular circulation due to its longer diffusion encoding time.

Random walk diffusion simulations in semi-permeable layered media with varying diffusivity

In this paper we present random walk based solutions to diffusion in semi-permeable layered media with varying diffusivity. We propose a novel transit model for solving the interaction of random walkers with a membrane. This hybrid model is based on treating the membrane permeability and the step change in diffusion coefficient as two interactions separated by an infinitesimally small layer. By conducting an extensive analytical flux analysis, the performance of our hybrid model is compared with a commonly used membrane transit model (reference model). Numerical simulations demonstrate the limitations of the reference model in dealing with step changes in diffusivity and show the capability of the hybrid model to overcome this limitation and to offer substantial gains in computational efficiency. The suitability of both random walk transit models for the application to simulations of diffusion tensor cardiovascular magnetic resonance (DT-CMR) imaging is assessed in a histology-based domain relevant to DT-CMR. In order to demonstrate the usefulness of the new hybrid model for other possible applications, we also consider a larger range of permeabilities beyond those commonly found in biological tissues.

Development of a cardiovascular magnetic resonance-compatible large animal isolated heart model for direct comparison of beating and arrested hearts.

Cardiac motion results in image artefacts and quantification errors in many cardiovascular magnetic resonance (CMR) techniques, including microstructural assessment using diffusion tensor cardiovascular magnetic resonance (DT‐CMR). Here, we develop a CMR‐compatible isolated perfused porcine heart model that allows comparison of data obtained in beating and arrested states. Ten porcine hearts (8/10 for protocol optimisation) were harvested using a donor heart retrieval protocol and transported to the remote CMR facility. Langendorff perfusion in a 3D‐printed chamber and perfusion circuit re‐established contraction. Hearts were imaged using cine, parametric mapping and STEAM DT‐CMR at cardiac phases with the minimum and maximum wall thickness. High potassium and lithium perfusates were then used to arrest the heart in a slack and contracted state, respectively. Imaging was repeated in both arrested states. After imaging, tissue was removed for subsequent histology in a location matched to the DT‐CMR data using fiducial markers. Regular sustained contraction was successfully established in six out of 10 hearts, including the final five hearts. Imaging was performed in four hearts and one underwent the full protocol, including colocalised histology. The image quality was good and there was good agreement between DT‐CMR data in equivalent beating and arrested states. Despite the use of autologous blood and dextran within the perfusate, T2 mapping results, DT‐CMR measures and an increase in mass were consistent with development of myocardial oedema, resulting in failure to achieve a true diastolic‐like state. A contiguous stack of 313 5‐μm histological sections at and a 100‐μm thick section showing cell morphology on 3D fluorescent confocal microscopy colocalised to DT‐CMR data were obtained. A CMR‐compatible isolated perfused beating heart setup for large animal hearts allows direct comparisons of beating and arrested heart data with subsequent colocalised histology, without the need for onsite preclinical facilities.

Gaps in Evidence for Risk Stratification for Sudden Cardiac Death in Hypertrophic Cardiomyopathy.

Gaps in Evidence for Risk Stratification for Sudden Cardiac Death in Hypertrophic Cardiomyopathy.

Diffusion tensor cardiovascular magnetic resonance predicts adverse remodelling after myocardial infarction

Abstract Background Changes in myocardial microstructure that underlie post-myocardial infarction (MI) left ventricular (LV) remodelling may contribute to progressive deterioration in cardiac function and increased risk of adverse clinical events. Diffusion Tensor Cardiovascular Magnetic Resonance (DT-CMR) derived parameters provide in vivo measures of helix angle (HA) and sheetlet angle (SA), which allow non-invasive characterization of microstructural dynamics associated with cardiac contraction. Purpose To evaluate the relationship between DT-CMR metrics of myocardial microstructure with the development of adverse LV remodelling and to determine the relationship between DT-CMR and strain post- MI. Methods We performed a longitudinal pre-clinical CMR study whereby DT-CMR, cine imaging and strain were acquired pre-MI and 3 days and 16 weeks post- MI in a pig model. HA (E1A), SA (E2A), and sheetlet angle mobility (ΔE2A = E2Asystole– E2Adiastole), as well as circumferential (Ecc) and radial (Err) strain were calculated at each timepoint and related to change in left ventricular end-diastolic volume (ΔLVEDV) and change in left ventricular end-systolic volume (ΔLVESV) between 3 days post-MI and 16 weeks post-MI. The translational value of this preclinical study was further assessed in six patients with chronic MI. Results ΔE2A over the whole LV (global ΔE2A) at 3 days post-MI correlated significantly with ΔLVEDV (R2=0.89, p=0.0013, Fig.1A;) and ΔLVESV (R2=0.81, p=0.0055, Fig.1B). Global Ecc at 3 days post-MI also correlated with both ΔLVEDV (R2=0.75, p=0.012, Fig.1C) and ΔLVESV (R2=0.71, p=0.018, Fig.1D). Global Err at 3 days post-MI did not show significant correlation with either ΔLVEDV (R2=0.32, p=0.19, Fig.1E) or ΔLVESV (R2=0.35, p=0.17, Fig.1F). Global ΔE2A correlated strongly with global Ecc 3 days post-MI (R2=0.9, p=0.00099, Fig.1G) but less strongly with global Err 3 days post-MI (R2=0.57, p=0.049, Fig.1H). Global ΔE2A at the chronic stage correlated significantly with ejection Fraction (EF), in both clinical (R2=0.87, p=0.007) and preclinical data (R2=0.87, p=0.0024). Global ΔE2A correlated well with LVEDV (clinical: R2=0.72, p=0.033; preclinical: R2=0.8, p=0.0066) and LVESV (clinical: R2=0.78, p=0.020; preclinical: R2=0.89, p=0.0013). In vivo E1A maps at 16 weeks post-MI and ex vivo DT-CMR demonstrated reduced right-handed helix angles in the endocardium of the infarct region. Conclusion ΔE2A measured at 3 day post-reperfused MI is strongly correlated with the development of increased end-systolic and end-diastolic volumes, and may therefore serve as a novel CMR early predictor of adverse LV remodelling after reperfused MI. Strong correlations between ΔE2A, LV volumes and EF in a small cohort of stable patients with remodelled hearts after chronic MI confirm the feasibility of performing these measurements in patients and the plausibility of further evaluation of ΔE2A as a predictor of adverse remodelling after reperfused MI. Sheetlet mobility predicts volume change Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): National Institutes of Health by the Division of Intramural Research (NHLBI, NIH, DHHS); British Heart Foundation

Diffusion tensor cardiovascular magnetic resonance in hypertrophic cardiomyopathy: a comparison of motion-compensated spin echo and stimulated echo techniques

ObjectivesDiffusion tensor cardiovascular magnetic resonance (DT-CMR) interrogates myocardial microstructure. Two frequently used in vivo DT-CMR techniques are motion-compensated spin echo (M2-SE) and stimulated echo acquisition mode (STEAM). Whilst M2-SE is strain-insensitive and signal to noise ratio efficient, STEAM has a longer diffusion time and motion compensation is unnecessary. Here we compare STEAM and M2-SE DT-CMR in patients.Materials and methodsBiphasic DT-CMR using STEAM and M2-SE, late gadolinium imaging and pre/post gadolinium T1-mapping were performed in a mid-ventricular short-axis slice, in ten hypertrophic cardiomyopathy (HCM) patients at 3 T.ResultsAdequate quality data were obtained from all STEAM, but only 7/10 (systole) and 4/10 (diastole) M2-SE acquisitions. Compared with STEAM, M2-SE yielded higher systolic mean diffusivity (MD) (p = 0.02) and lower fractional anisotropy (FA) (p = 0.02, systole). Compared with segments with neither hypertrophy nor late gadolinium, segments with both had lower systolic FA using M2-SE (p = 0.02) and trend toward higher MD (p = 0.1). The negative correlation between FA and extracellular volume fraction was stronger with STEAM than M2-SE (r2 = 0.29, p < 0.001 STEAM vs. r2 = 0.10, p = 0.003 M2-SE).DiscussionIn HCM, only STEAM reliably assesses biphasic myocardial microstructure. Higher MD and lower FA from M2-SE reflect the shorter diffusion times. Further work will relate DT-CMR parameters and microstructural changes in disease.

High resolution in-vivo DT-CMR using an interleaved variable density spiral STEAM sequence.

Diffusion tensor cardiovascular magnetic resonance (DT-CMR) has a limited spatial resolution. The purpose of this study was to demonstrate high-resolution DT-CMR using a segmented variable density spiral sequence with correction for motion, off-resonance, and T2*-related blurring. A single-shot stimulated echo acquisition mode (STEAM) echo-planar-imaging (EPI) DT-CMR sequence at 2.8 × 2.8 × 8 mm3 and 1.8 × 1.8 × 8 mm3 was compared to a single-shot spiral at 2.8 × 2.8 × 8 mm3 and an interleaved spiral sequence at 1.8 × 1.8 × 8 mm3 resolution in 10 healthy volunteers at peak systole and diastasis. Motion-induced phase was corrected using the densely sampled central k-space data of the spirals. STEAM field maps and T2* measures were obtained using a pair of stimulated echoes each with a double spiral readout, the first used to correct the motion-induced phase of the second. The high-resolution spiral sequence produced similar DT-CMR results and quality measures to the standard-resolution sequence in both cardiac phases. Residual differences in fractional anisotropy and helix angle gradient between the resolutions could be attributed to spatial resolution and/or signal-to-noise ratio. Data quality increased after both motion-induced phase correction and off-resonance correction, and sharpness increased after T2* correction. The high-resolution EPI sequence failed to provide sufficient data quality for DT-CMR reconstruction. In this study, an in vivo DT-CMR acquisition at 1.8 × 1.8 mm2 in-plane resolution was demonstrated using a segmented spiral STEAM sequence. Motion-induced phase and off-resonance corrections are essential for high-resolution spiral DT-CMR. Segmented variable density spiral STEAM was found to be the optimal method for acquiring high-resolution DT-CMR data.

Novel insights into in-vivo diffusion tensor cardiovascular magnetic resonance using computational modeling and a histology-based virtual microstructure.

PurposeTo develop histology‐informed simulations of diffusion tensor cardiovascular magnetic resonance (DT‐CMR) for typical in‐vivo pulse sequences and determine their sensitivity to changes in extra‐cellular space (ECS) and other microstructural parameters.MethodsWe synthesised the DT‐CMR signal from Monte Carlo random walk simulations. The virtual tissue was based on porcine histology. The cells were thickened and then shrunk to modify ECS. We also created idealised geometries using cuboids in regular arrangement, matching the extra‐cellular volume fraction (ECV) of 16–40%. The simulated voxel size was 2.8 × 2.8 × 8.0 mm3 for pulse sequences covering short and long diffusion times: Stejskal–Tanner pulsed‐gradient spin echo, second‐order motion‐compensated spin echo, and stimulated echo acquisition mode (STEAM), with clinically available gradient strengths.ResultsThe primary diffusion tensor eigenvalue increases linearly with ECV at a similar rate for all simulated geometries. Mean diffusivity (MD) varies linearly, too, but is higher for the substrates with more uniformly distributed ECS. Fractional anisotropy (FA) for the histology‐based geometry is higher than the idealised geometry with low sensitivity to ECV, except for the long mixing time of the STEAM sequence. Varying the intra‐cellular diffusivity (D IC) results in large changes of MD and FA. Varying extra‐cellular diffusivity or using stronger gradients has minor effects on FA. Uncertainties of the primary eigenvector orientation are reduced using STEAM.ConclusionsWe found that the distribution of ECS has a measurable impact on DT‐CMR parameters. The observed sensitivity of MD and FA to ECV and D IC has potentially interesting applications for interpreting in‐vivo DT‐CMR parameters.

An in-vivo comparison of stimulated-echo and motion compensated spin-echo sequences for 3\xa0T diffusion tensor cardiovascular magnetic resonance at multiple cardiac phases

BackgroundStimulated-echo (STEAM) and, more recently, motion-compensated spin-echo (M2-SE) techniques have been used for in-vivo diffusion tensor cardiovascular magnetic resonance (DT-CMR) assessment of cardiac microstructure. The two techniques differ in the length scales of diffusion interrogated, their signal-to-noise ratio efficiency and sensitivity to both motion and strain. Previous comparisons of the techniques have used high performance gradients at 1.5 T in a single cardiac phase. However, recent work using STEAM has demonstrated novel findings of microscopic dysfunction in cardiomyopathy patients, when DT-CMR was performed at multiple cardiac phases. We compare STEAM and M2-SE using a clinical 3 T scanner in three potentially clinically interesting cardiac phases.MethodsBreath hold mid-ventricular short-axis DT-CMR was performed in 15 subjects using M2-SE and STEAM at end-systole, systolic sweet-spot and diastasis. Success was defined by ≥50% of the myocardium demonstrating normal helix angles. From successful acquisitions DT-CMR results relating to tensor orientation, size and shape were compared between sequences and cardiac phases using non-parametric statistics. Strain information was obtained using cine spiral displacement encoding with stimulated echoes for comparison with DT-CMR results.ResultsAcquisitions were successful in 98% of STEAM and 76% of M2-SE cases and visual helix angle (HA) map scores were higher for STEAM at the sweet-spot and diastasis. There were significant differences between sequences (p < 0.05) in mean diffusivity (MD), fractional anisotropy (FA), tensor mode, transmural HA gradient and absolute second eigenvector angle (E2A). Differences in E2A between systole and diastole correlated with peak radial strain for both sequences (p ≤ 0.01).ConclusionM2-SE and STEAM can be performed equally well at peak systole at 3 T using standard gradients, but at the sweet-spot and diastole STEAM is more reliable and image quality scores are higher. Differences in DT-CMR results are potentially due to differences in motion sensitivity and the longer diffusion time of STEAM, although the latter appears to be the dominant factor. The benefits of both sequences should be considered when planning future studies and sequence and cardiac phase specific normal ranges should be used for comparison.

Diffusion tensor cardiovascular magnetic resonance with a spiral trajectory: An in vivo comparison of echo planar and spiral stimulated echo sequences.

Diffusion tensor cardiovascular MR (DT-CMR) using stimulated echo acquisition mode (STEAM) with echo-planar-imaging (EPI) readouts is a low signal-to-noise-ratio (SNR) technique and therefore typically has a low spatial resolution. Spiral trajectories are more efficient than EPI, and could increase the SNR. The purpose of this study was to compare the performance of a novel STEAM spiral DT-CMR sequence with an equivalent established EPI technique. A STEAM DT-CMR sequence was implemented with a spiral readout and a reduced field of view. An in vivo comparison of DT-CMR parameters and data quality between EPI and spiral was performed in 11 healthy volunteers imaged in peak systole and diastasis at 3 T. The SNR was compared in a phantom and in vivo. There was a greater than 49% increase in the SNR in vivo and in the phantom measurements (in vivo septum, systole: SNREPI = 8.0 ± 2.2, SNRspiral = 12.0 ± 2.7; diastasis: SNREPI = 8.1 ± 1.6, SNRspiral = 12.0 ± 3.7). There were no significant differences in helix angle gradient (HAG) (systole: HAGEPI = -0.79 ± 0.07 °/%; HAGspiral = -0.74 ± 0.16 °/%; P = 0.11; diastasis: HAGEPI = -0.63 ± 0.05 °/%; HAGspiral = -0.56 ± 0.14 °/%; P = 0.20), mean diffusivity (MD) in systole (MDEPI = 0.99 ± 0.06 × 10-3 mm2 /s, MDspiral = 1.00 ± 0.09 × 10-3 mm2 /s, P = 0.23) and secondary eigenvector angulation (E2A) (systole: E2AEPI = 61 ± 10 °; E2Aspiral = 63 ± 10 °; P = 0.77; diastasis: E2AEPI = 18 ± 11 °; E2Aspiral = 15 ± 8 °; P = 0.20) between the sequences. There was a small difference (≈ 20%) in fractional anisotropy (FA) (systole: FAEPI = 0.49 ± 0.03, FAspiral = 0.41 ± 0.04; P < 0.01; diastasis: FAEPI = 0.66 ± 0.05, FAspiral = 0.55 ± 0.03; P < 0.01) and mean diffusivity in diastasis (10%; MDEPI = 1.00 ± 0.12 × 10-3 mm2 /s, MDspiral = 1.10 ± 0.09 × 10-3 mm2 /s, P = 0.02). This is the first study to demonstrate DT-CMR STEAM using a spiral trajectory. The SNR was increased by using a spiral rather than the more established EPI readout, and the DT-CMR parameters were largely similar between the two sequences. Magn Reson Med 80:648-654, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

018 DT-CMR imaging of deranged microstructure in situs inversus totalis

Background Diffusion tensor cardiovascular magnetic resonance (DT-CMR) is a non-invasive technique that has been histologically validated to provide information on the microstructure of the myocardium.1–3 There is a standard helical myocyte arrangement in the situs solitus (SS) heart, as viewed from the apex; left-handed in the epicardium, circumferential in the mesocardium and right-handed in the endocardium. This generates the opposing basal clockwise rotation and apical anticlockwise rotation necessary for torsion.4 However in situs inversus totalis (SIT) there is mirror image arrangement of the visceral organs. There are no histological studies assessing how myocardial microstructure is affected in SIT. DT-CMR offers a unique opportunity to evaluate the microstructural abnormalities in SIT. Methods 12 SIT patients and 12 matched healthy volunteers were scanned in a 3T Siemens Skyra scanner. DT-CMR was performed at peak systole in the short axis at base, mid and apex. 2 people had whole heart tractography. A STEAM sequence with bmain=600 s/mm2 and bref=150 s/mm2 was used, as previously described.3 Strain and torsion assessment was performed using DENSE5. Results Patients were age and sex-matched (SIT 39.5 and SS 34.5 years, 3/12 male). Myocyte organisation at base, mid and apex was significantly different in SIT hearts compared to the SS hearts. Figure 1 shows example tractography. In SS, the endocardial positive helix angle (HA) progressed to a negative HA in the epicardium. In SIT hearts this pattern was inverted at the base and approached normal at the apex, with a mid-ventricular transition zone. Mid-ventricular peak radial and circumferential strain were reduced in SIT (0.4±0.16 vs 0.56±0.16, p=0.02, and −0.16±0.02 vs −0.18±0.01 p=0.04 respectively). Peak absolute torsion was reduced in SIT 3.6° [3.6°] vs 8.0° [3.5°]. Conclusion This is the first human DT-CMR study of SIT hearts. We demonstrate that the SIT heart has an inverted myocyte orientation at the base that approaches normal towards the apex. Peak absolute torsion is reduced. Peak radial and circumferential strain are also reduced at the mid-ventricle. The deranged microstructure in SIT has functional effects, the long-term outcomes of which require further study. References . Reese TG, Weisskoff RM, Smith RN, et al. Imaging myocardial fibre architecture in vivo with magnetic resonance. Magn Reson Med 1995;34(6):786–791. Scollan DF, Holmes A, Winslow R, et al. Histological validation of myocardial microstructure obtained from diffusion tensor magnetic resonance imaging. Am J Physiol Heart Circ Physiol1998;275(6):H2308–H2318. Nielles-Vallespin S, Khalique Z, Ferreira PF,et al. Assessment of Myocardial Microstructural Dynamics by In Vivo Diffusion Tensor Cardiac Magnetic Resonance. J Am Coll Cardiol2017;69(6):661–676. SenguptaPP, Tajik AJ, Chandrasekaran K, et al. Twist Mechanics of the Left Ventricle: Principles and Application. JACC: Cardiovascular Imaging2008;1(3):366– 376. Scott AD, Tayal U, Nielles-Vallespin S, et al. Accelerating cine DENSE using a zonal excitation. J Cardiov Magn Reson 2016;18(1):O50.

A high-resolution cardiovascular magnetic resonance diffusion tensor map from ex-vivo C57BL/6 murine hearts.

BackgroundThe complex cardiac fiber structural organization and spatial arrangement of cardiomyocytes in laminar sheetlets contributes greatly to cardiac functional and contractile ejection patterns. This study presents the first comprehensive, ultra-high resolution, fully quantitative statistical tensor map of the fixed murine heart at isotropic resolution of 43 μm using diffusion tensor (DT) cardiovascular magnetic resonance (CMR).MethodsImaging was completed in approximately 12 hours using a six-directional encoding scheme, in five ex vivo healthy C57BL/6 mouse hearts. The tensor map constructed from this data provides an average description of the murine fiber architecture visualized with fiber tractography, and its population variability, using the latest advances in image tensor analysis and statistics.ResultsResults show that non-normalized cardiac tensor maps are associated with mean fractional anisotropy of 0.25 ± 0.07 and mean diffusivity of 8.9 ± 1.6 × 10−4 mm2/s. Moreover, average mid-ventricular helical angle distributions ranged between –41 ± 3° and +52 ± 5° and were highly correlated with transmural depth, in agreement with prior published results in humans and canines. Calculated variabilities of local myocyte orientations were 2.0° and 1.4°. Laminar sheet orientation variability was found to be less stable at 2.6°. Despite such variations, the murine heart seems to be highly structured, particularly when compared to canines and humans.ConclusionsThis tensor map has the potential to yield an accurate mean representation and identification of common or unique features of the cardiac myocyte architecture, to establish a baseline standard reference of DTI indices, and to improve detection of biomarkers, especially in pathological states or post-transgenetic modifications.

Erratum to: reproducibility of in-vivo diffusion tensor cardiovascular magnetic resonance in hypertrophic cardiomyopathy

Erratum to: reproducibility of in-vivo diffusion tensor cardiovascular magnetic resonance in hypertrophic cardiomyopathy