Variation Of Signal Intensity Research Articles

Toward a Standardization of Ultrasound Scanners for Dynamic Contrast-Enhanced Ultrasonography: Methodology and Phantoms

The standardization of ultrasound scanners for dynamic contrast-enhanced ultrasonography (DCE-US) is mandatory for evaluation of clinical multicenter studies. We propose a robust method using a phantom for measuring the variation of the harmonic signal intensity obtained from the area under the time-intensity curve versus various contrast-agent concentrations. The slope of this measured curve is the calibration parameter. We tested our method on two devices from the same manufacturer (AplioXV and Aplio500, Toshiba, Tokyo, Japan) using the same settings as defined for a French multicenter study. The Aplio500's settings were adjusted to match the slopes of the AplioXV, resulting in the following settings on the Aplio500: at 3.5 MHz: MI = 0.15; CG = 35 dB and at 8 MHz: MI = 0.10; CG = 32 dB. This calibration method is very important for future DCE-US multicenter studies.

Gold nanoparticles-decorated electrospun poly(N-vinyl-2-pyrrolidone) nanofibers with tunable size and coverage density for nanomolar detection of single and binary component dyes by surface-enhanced raman spectroscopy

The application of the electrospun nanomaterials to surface-enhanced Raman spectroscopy (SERS) is a rapidly evolving field which holds potential for future developments in the generation of portable plasmonic-based detection platforms. In this study, a simple approach to fabricate electrospun poly(N-vinylpyrrolidone) (PVP) mats decorated with gold nanoparticles (AuNPs) by combining electrospinning and calcination was presented. AuNPs were decorated on the fiber mat surface through electrostatic interactions between positively charged aminosilane groups and negatively charged AuNPs. The size and coverage density of AuNPs on the fiber mats could be tuned by varying the calcination temperature. Calcination of AuNPs-decorated PVP fibers at 500 °C–700 °C resulted in the uniform decoration of high density AuNPs with very narrow gaps on every single fiber, which in turn contribute to strong electromagnetic SERS enhancement. The robust free-standing AuNPs-decorated mat which calcined at 500 °C (500/AuNPs-F) exhibited high SERS activity toward cationic (methylene blue, MB) and anionic (methyl orange, MO) dyes in single and binary systems with a detection range from tens of nM to a few hundred μM. The fabricated SERS substrate demonstrated high reproducibility with the spot-to-spot variation in SERS signal intensities was ±10% and ±12% for single and binary dye systems, respectively. The determination of MB and MO in spiked river water and tap water with 500/AuNPs-F substrate gave satisfactory results in terms of the percent spike recoveries (ranging from 92.6%–96.6%) and reproducibility (%RSD values less than 15 for all samples).

Preclinical Alterations in Myocardial Microstructure in People with Metabolic Syndrome

ObjectiveMetabolic syndrome (MetS) can lead to myocardial fibrosis, diastolic dysfunction and eventual heart failure. We evaluated alterations in myocardial microstructure in people with MetS using a novel algorithm to characterize ultrasonic signal intensity variation.MethodsAmong 254 participants without existing cardiovascular disease (mean age 42 ± 11 years, 75% women), there were 162 with MetS, 47 with obesity without MetS, and 45 non-obese controls. Standard echocardiography was performed, and a novel validated computational algorithm was used to investigate myocardial microstructure based on sonographic signal intensity and distribution. We examined the signal intensity coefficient (SIC, left ventricular microstructure).ResultsThe SIC was significantly higher in people with MetS compared with people with (P<0.001) and without obesity (P=0.04), even after adjustment for age, sex, body mass index, hypertension, diabetes mellitus and triglyceride to HDL cholesterol (TG/HDL) ratio (P<0.05 for all). Clinical correlates of SIC included TG concentrations (r=0.21, P=0.0007) and the TG/HDL ratio (r=0.2, P=0.001).ConclusionsOur findings suggest that preclinical MetS and dyslipidemia in particular, are associated with altered myocardial signal intensity variation. Future studies are needed to determine whether the SIC may help detect subclinical disease in people with metabolic disease, with the ultimate goal of targeting preventive efforts.

Serum metabolomic profiling highlights pathways associated with liver fat content in a general population sample.

Fatty liver disease (FLD) is an important intermediate trait along the cardiometabolic disease spectrum and strongly associates with type 2 diabetes. Knowledge of biological pathways implicated in FLD is limited. An untargeted metabolomic approach might unravel novel pathways related to FLD. In a population-based sample (n=555) from Northern Germany, liver fat content was quantified as liver signal intensity using magnetic resonance imaging. Serum metabolites were determined using a non-targeted approach. Partial least squares regression was applied to derive a metabolomic score, explaining variation in serum metabolites and liver signal intensity. Associations of the metabolomic score with liver signal intensity and FLD were investigated in multivariable-adjusted robust linear and logistic regression models, respectively. Metabolites with a variable importance in the projection >1 were entered in in silico overrepresentation and pathway analyses. In univariate analysis, the metabolomics score explained 23.9% variation in liver signal intensity. A 1-unit increment in the metabolomic score was positively associated with FLD (n=219; odds ratio: 1.36; 95% confidence interval: 1.27-1.45) adjusting for age, sex, education, smoking and physical activity. A simplified score based on the 15 metabolites with highest variable importance in the projection statistic showed similar associations. Overrepresentation and pathway analyses highlighted branched-chain amino acids and derived gamma-glutamyl dipeptides as significant correlates of FLD. A serum metabolomic profile was associated with FLD and liver fat content. We identified a simplified metabolomics score, which should be evaluated in prospective studies.

Three-dimensional oxygen-enhanced MRI of the human lung at 1.5T with ultra-fast balanced steady-state free precession.

To assess the feasibility of 3D oxygen-enhanced (OE) MRI of the lung at 1.5T using multi-volumetric ultra-fast balanced steady-state free precession (ufSSFP) acquisitions. Isotropic imaging of the lung for OE-MRI was performed with an adapted 3D ufSSFP sequence using five breath-hold acquisitions ranging from functional residual capacity to tidal inspiration under both normoxic (room air) and hyperoxic (100% O2 ) gas conditions. For each O2 concentration, a sponge model (which captures the parenchymal signal intensity variation as a function of the lung volume) was fitted to the acquired multi-volumetric datasets after semiautomatic lung segmentation and deformable image registration. From the retrieved model parameters, 3D oxygen-enhancement maps were calculated. For OE ufSSFP imaging, the maximum parenchymal signal is observed for flip angles around 23° under both normoxic and hyperoxic conditions. It is found that the sponge model accurately describes parenchymal signal at different breathing positions, thereby mitigating the confounding bias in the estimated oxygen enhancement from residual density modulations. From the model, an average lung oxygen enhancement of 7.0% ± 0.3% was found in the healthy volunteers, and the oxygen-enhancement maps indicate a ventral to dorsal gravitation-related gradient. The study demonstrates the feasibility of whole-lung OE-MRI from multi-volumetric ufSSFP in healthy volunteers. Magn Reson Med 79:246-255, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

Brain correlates to facial motor imagery and its somatotopy in the primary motor cortex.

Motor imagery (MI) has attracted increased interest for motor rehabilitation as many studies have shown that MI shares the same neural networks as motor execution (ME). Nevertheless, MI in terms of facial movement has not been studied extensively; thus, in the present study, we investigated shared neural networks between facial motor imagery (FMI) and facial motor execution (FME). In addition, FMI somatotopy within-face was investigated between the forehead and the mouth. Functional MRI was used to examine 34 healthy individuals with ME and MI paradigms for the forehead and the mouth. The general linear model and a paired t-test were performed to define the facial area in the primary motor cortex (M1) and this area has been used to investigate somatotopy between the forehead and mouth FMI. FMI recruited similar brain motor areas as FME, but showed less neural activity in all activated regions. The facial areas in M1 were distinguishable from other body movements such as finger movement. Further investigation of this area showed that forehead and mouth imagery tended to lack a somatotopic representation for position on M1, and yet had distinct characteristics in terms of neural activity level. FMI showed different characteristics from general MI as the former exclusively activated facial processing areas. In addition, FME and FMI showed different characteristics in terms of BOLD signal level, while sharing the same neural areas. The results imply a potential usefulness of MI training for rehabilitation of facial motor disease considering that forehead and mouth somatotopy showed no clear position difference, and yet showed a significant BOLD signal intensity variation.

Combination of principal component analysis and optical-flow motion compensation for improved cardiac MR thermometry

The use of magnetic resonance (MR) thermometry for the monitoring of thermal ablation is rapidly expanding. However, this technique remains challenging for the monitoring of the treatment of cardiac arrhythmia by radiofrequency ablation due to the heart displacement with respiration and contraction. Recent studies have addressed this problem by compensating in-plane motion in real-time with optical-flow based tracking technique. However, these algorithms are sensitive to local variation of signal intensity on magnitude images associated with tissue heating. In this study, an optical-flow algorithm was combined with a principal component analysis method to reduce the impact of such effects. The proposed method was integrated to a fully automatic cardiac MR thermometry pipeline, compatible with a future clinical workflow. It was evaluated on nine healthy volunteers under free breathing conditions, on a phantom and in vivo on the left ventricle of a sheep. The results showed that local intensity changes in magnitude images had lower impact on motion estimation with the proposed method. Using this strategy, the temperature mapping accuracy was significantly improved.

M-Cresol purple functionalized surface enhanced Raman scattering paper chips for highly sensitive detection of pH in the neutral pH range.

Herein, a pH sensitive paper SERS chip was prepared by selecting m-cresol purple, a molecule with halochromic properties in the neutral pH range as a Raman reporter. The adsorbed m-cresol purple underwent a reversible change in its electronic configuration from a non-resonant species to a resonant species, which resulted in a significant Raman signal intensity variation due to the transformation of the sensing mode from SERS to surface-enhanced resonance Raman scattering (SERRS). The chips have a sensitive pH range of 6.0 to 8.0 and exhibited good performance for the detection of natural water samples with detection precision of approximately 0.03 pH units, suggesting great potential for environmental pH monitoring applications.

Structural, Thermal and Optical Properties of Mn2+ Doped Methacrylic Acid – Ethyl Acrylate (MAA:EA) Copolymer Films

Abstract Pure and Mn2+ doped Methacrylic Acid Ethylacrylate (MAA:EA) copolymer films were prepared by using the solution cast technique. Investigations were conducted using DSC, TGA, XRD, FTIR, UV–Vis, SEM and EPR. Thermal properties of these films were investigated with differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Using the DSC thermograms, glass transition temperature (Tg ) and melting temperature (Tm ) of copolymer films were measured. Thermogravimetric curves of the pure and Mn2+ doped MAA:EA copolymer showed two distinct steps of weight loss. The optical absorbance of the pure and Mn2+ doped films were measured in the 200–800 nm wavelength range. The values of absorption edge, direct and indirect band gaps were calculated. The optical band gap decreased with the increase of mol% of Mn2+ ions. The enhanced amorphous nature of the doped copolymer has been identified from X-ray diffraction analysis. FTIR spectral studies of pure and Mn2+ doped MAA:EA copolymer films display significant structural changes within the copolymer film indicating the complexation. The morphology of the copolymer samples was examined by scanning electron microscopy (SEM). EPR spectra of all the doped samples exhibit a single absorption line centered at g=2.005. The observed variation in the EPR signal intensity is due to the existence of interacting paramagnetic centers.

Real-time SPARSE-SENSE cine MR imaging in atrial fibrillation: a feasibility study.

Background Cardiac magnetic resonance imaging (MRI) relies on correct ECG-gating, which is hindered in arrhythmia. Purpose To examine whether a prototype free-breathing real-time cine sequence using SPARSE-SENSE (SPARSE) improves left ventricular quantification in atrial fibrillation. Material and Methods On a 1.5T MR system left ventricular short-axis stacks were acquired of the SPARSE sequence and of a "reference" steady-state free precession (SSFP) sequence with arrhythmia rejection in 20 patients with atrial fibrillation. Two radiologists independently rated arrhythmia-caused artifact severity in both sequences using a 4-point scale. Coefficients of variation of myocardial signal intensity for both sequences were acquired. Volumetry was performed twice by one reader and once by another reader. Correlation between artifact severity and employed sequence was analyzed by modified Fisher's exact test. Coefficients of variation and volumetric data were compared by paired t-test and intraclass correlation. Results Median arrhythmia-caused artifact severity was 2 in both readers for SSFP and 0 (reader 1)/1 (reader 2) for SPARSE, being significantly lower in SPARSE ( P < 0.001). Mean coefficient of variance was significantly smaller in SPARSE (0.11 ± 0.04) compared to SSFP (0.22 ± 0.13, P = 0.003), which was interpreted as a hint for fewer artifacts in SPARSE. Only a small difference of 9 ± 15 mL was seen for end-systolic volume ( P = 0.019) between sequences, otherwise no significant difference was detected (end-diastolic volume, P = 0.200; stroke volume, P = 0.554; ejection fraction, P = 0.136; myocardial mass, P = 0.353). Intraclass correlation between sequences was good to excellent (range, 0.80-0.97). Conclusion Real-time MRI with SPARSE data sampling is promising in atrial fibrillation because it reduces arrhythmia-caused artifacts.

INVESTIGATION OF RADIOSENSITIVITY OF GAMMA IRRADIATED ISONIAZID ANTIBIOTIC THROUGH EPR SPECTROSCOPY

Dosimetric properties of gamma irradiated Isoniazid (IS) were investigated through Electron Paramagnetic Resonance (EPR) spectroscopy. While unirradiated IS presented no EPR signal, irradiated IS exhibited a significant EPR spectrum at room temperature. Some EPR parameters of obtained experimental spectrum were calculated. In order to describe the variation of EPR signal intensity with absorbed radiaiton dose, several mathematical equations were tried. It has been determined that the best fit of IS sample is with polinomial function (R 2 = 0.9675). Moreover time dependency of the intensity of the EPR signal of the irradiated sample was analysed to study the stability of the free radicals.

In Vivo Assessment of Brainstem Depigmentation in Parkinson Disease: Potential as a Severity Marker for Multicenter Studies.

Purpose To investigate the pattern of neuromelanin signal intensity loss within the substantia nigra pars compacta (SNpc), locus coeruleus, and ventral tegmental area in Parkinson disease (PD); the specific aims were (a) to study regional magnetic resonance (MR) quantifiable depigmentation in association with PD severity and (b) to investigate whether imaging- and platform-dependent signal intensity variations can be normalized. Materials and Methods This prospective case-control study was approved by the local ethics committee and the research department of Nottingham University Hospitals. Written informed consent was obtained from all participants before enrollment in the study. Sixty-nine participants (39 patients with PD and 30 control subjects) were investigated with neuromelanin-sensitive MR imaging by using two different 3-T platforms and three differing protocols. Neuromelanin-related volumes of the anterior and posterior SNpc, locus coeruleus, and ventral tegmental area were determined, and normalized neuromelanin volumes were assessed for protocol-dependent effects. Diagnostic test performance of normalized neuromelanin volume was investigated by using receiver operating characteristic analyses, and correlations with the Unified Parkinson's Disease Rating Scale scores were tested. Results Reduction of normalized neuromelanin volume in PD was most pronounced in the posterior SNpc (median, -83%; P < .001), followed by the anterior SNpc (-49%; P < .001) and the locus coeruleus (-37%; P < .05). Normalized neuromelanin volume loss of the posterior and whole SNpc allowed the best differentiation of patients with PD and control subjects (area under the receiver operating characteristic curve, 0.92 and 0.88, respectively). Normalized neuromelanin volume of the anterior, posterior, and whole SNpc correlated with Unified Parkinson's Disease Rating Scale scores (r2 = 0.25, 0.22, and 0.28, respectively; all P < .05). Conclusion PD-induced neuromelanin loss can be quantified across imaging protocols and platforms by using appropriate adjustment. Depigmentation in PD follows a distinct spatial pattern, affords high diagnostic accuracy, and is associated with disease severity. ©RSNA, 2016 Online supplemental material is available for this article.

Structural, Thermal and Optical Properties of Pure and Mn2+ Doped Poly(Vinyl Chloride) Films

Pure and Mn2+ doped poly(vinyl chloride) (PVC) polymer films were prepared using the solution cast technique. The prepared samples have been characterized by X-ray diffraction (XRD), UV-Vis Spectroscopy (UV-Vis), Fourier transform infrared (FTIR) Spectroscopy, Thermogravimetric analysis (TGA), Differential Scanning Calorimetry (DSC), Electron Paramagnetic Resonance (EPR) and Scanning Electron Microscopy (SEM) studies. TGA/DSC analysis reveals that the sample is thermally stable upto 350 0C. The morphology of the polymer films was studied by SEM. The optical absorbance of the polymer films was measured in the 200-900 nm wavelength range. The absorption edge, direct band gap and indirect band gap have been evaluated. The FTIR spectrum exhibits several bands characteristics of stretching and bending vibrations of C - Cl, C - H, C = C and O - H groups. The EPR Spectra at room temperature were used to calculate the number of spins and paramagnetic susceptibility as a function of dopant concentration. All the Mn2+ doped PVC samples exhibit a signal centred at geff = 1.9. The observed variation in the EPR signal intensity is due to the variation in the dopant concentration. The complexation of Mn2+ ion with the polymer was confirmed by XRD studies.

DNA self-assembly on graphene surface studied by SERS mapping

The self-assembly of double-stranded DNA (dsDNA) segments on two variations of graphene surfaces having nano-platelets with different lateral sizes and thicknesses was investigated using surface-enhanced Raman spectroscopy (SERS) and electrical impedance spectroscopy (EIS) techniques. Due to the strong local field-enhancement, the SERS signals from functional molecules bound to the graphene edges and from DNA moieties were recorded. Relative intensities of specific Raman modes were used as contrast parameters to build Raman signal intensity maps. The observed variation in the SERS signal intensity was related to the different configuration (tilted or flattened) in which dsDNA segments are assembled on the carbon surface, depending on the graphene platelet size. EIS was used to characterize the conductive properties of nano-structured films containing pristine or DNA-functionalized graphene nano-platelets. Results from the EIS analysis supported the SERS findings and confirmed that SERS mapping is a reliable method for a rapid monitoring of the procedures used to interface DNA with graphene surfaces. The present study, linking DNA anchoring morphology to the conductive properties of nano-structured hybrid films, contribute to define a new approach in the optimization of biosensor design.

The mutual effect of metal sample and turboflame in LIBS signal enhancement

The main aim of the present study is to evaluate the mutual effect of copper sample and turboflame in laser induced breakdown spectroscopy (LIBS) signal enhancement. The use of copper sample leads to a signal enhancement in CN (B2Σ+–X2Σ+) 384.2–388.4 nm molecular transition, N742nm, N744nm, N746nm (a triplet generated by the fine splitting of the 2s22p2(3P)3s–2s22p2(3P)3p transition) and Hα, 656.3 nm (as a flame inductor) atomic lines analysis. Additionally, increase in copper sample temperature with flame can enhance the Cu atomic line intensities (as copper sample inductors). Moreover, in this paper, the comparison between turboflame and alcohol flame on LIBS analysis was studied. LIBS signal intensity variation in a turboflame and turboflame coupled with copper sample at different laser pulse energies indicated that the low laser pulse energy could be compensated by using a copper sample that is coupled with turboflame and improved LIBS signal enhancement. For flames analysis, the use of metal sample in LIBS method is demonstrated to be costeffective, compact, and capable of signal enhancement.

Laser-based investigation of the transition from droplets to nanoparticles in flame-assisted spray synthesis of functional nanoparticles

Mechanisms involved in flame-assisted-spray-pyrolysis (FASP) synthesis of TiO2-based functional nanoparticles are investigated using in situ phase-selective laser-induced breakdown spectroscopy. Specifically, the transition from droplets to nanoparticles is examined, as well as the particle growth process in the post flame region. In contrast to vapor-fed flame synthesis, the existence of the precursor breakdown in sprayed droplets is observed by both Ti atomic signal and Bremsstrahlung emissions. The emission signal intensity variation reveals the transition from droplets to nanoparticles, indicating that the competition between precursor vaporization and nascent particle formation is the rate determining factor. For the ensuing particle growth regime, the prediction of the particle size evolution by a polydispersed population balance model is in good agreement with TEM and laser-diagnostics results, demonstrating that the particle growth is governed by the collision-coagulation mechanism. Besides, the transition from droplets to nanoparticles can be accelerated with sufficient OH radicles provided by combustible solvents. Furthermore, doping of TiO2 with V and Zr will lead to changes in band gap of the nanoparticle observed, i.e., a distinct strengthening by 23% with V doping and a weakening by 22% with Zr doping in the intensity of Ti signal, respectively.

Application of HAADF STEM image analysis to structure determination in rotationally disordered and amorphous multilayered films

We report results from high angle annular dark field scanning transmission electron microscopy (HAADF STEM) image analysis of complex semi-crystalline and amorphous materials, and apply the insights gained from local structure information towards global structure determination. Variations in HAADF STEM intensities for a rotationally disordered heterostructure and an amorphous oxide film are statistically analyzed to extract information regarding the inhomogeneity of the films perpendicular to the substrate. By assuming chemical homogeneity in the film axis parallel to the substrate, the signal intensity variation parallel to the substrate is used to estimate the signal noise level, allowing evaluation of the significance of intensity differences in the substrate normal direction. The positions of HAADF STEM intensity peaks in the perpendicular direction, averaged from multiple images, provide a valuable initial model for a Rietveld refinement of the global c-axis structure of the heterostructure. For an amorphous multi-coat solution-cast oxide sample, the analysis reveals statistically significant variations in the HAADF STEM intensity profile perpendicular to the substrate. These variations indicate an inhomogeneous density profile, presumably related to the spin-casting of individual layers and have implications for understanding the chemical interactions that occur between layers when preparing multilayer amorphous oxide films from solution.

Preparation and characterization of pure and copper-doped PVC films

Abstract Pure and Cu2+-doped polyvinyl chloride (PVC) polymer films were prepared using the solution cast technique. Investigations were conducted using DSC, TGA, XRD, FT-IR, UV–Vis, SEM and EPR. Differential scanning calorimetry studies suggested that the Cu2+ samples have higher values of the glass transition (T g) temperature, and thermo gravimetric studies show that weight loss of polymer film indicates the improved thermal stability of the polymer film. The features of the complexation of the polymer films were studied by X-ray diffraction. FT-IR spectra exhibits the bands in three regions, which are attributed to C–Cl, C–C and numerous CH groups of stretching and bending vibrations. The absorption spectra have been recorded in the wavelength range 200–900 nm. The absorption edge, direct bandgap, indirect bandgap and urbach energy have been evaluated. Film morphology was examined by scanning electron microscopy. XRD, DSC and SEM reveal the amorphous nature and surface morphology of polymer films, respectively. Electron paramagnetic resonance studies were used to calculate the number of spins and paramagnetic susceptibility as a function of dopant concentration, all the Cu2+-doped PVC samples exhibit signal with g values g ⊥=2.176 and g ||=2.254. The observed variation in the EPR signal intensity is due to variation in the dopant concentration.

The effects of solar flares on the very low frequency signals recorded by super SID system

Solar flares cause sudden disturbances at the Earth’s ionosphere. These effects are detected by the very low frequency (VLF), 3−30-kHz signals which are propagated at the Earth-ionosphere waveguide. The sudden changes on the time-dependent intensity of VLF signals are recorded by Super SID system during February, March, and April, 2013. Then VLF data were compared with the GOES satellite data found in the Space Environment Center online database. The main factors of the variation in VLF signal intensities recorded by the Super SID system are class, duration of the solar flare and the frequency of VLF signals.

Parameter optimization for reproducible cardiac 1 H-MR spectroscopy at 3 Tesla.

To optimize data acquisition parameters in cardiac proton MR spectroscopy, and to evaluate the intra- and intersession variability in myocardial triglyceride content. Data acquisition parameters at 3 Tesla (T) were optimized and reproducibility measured using, in total, 49 healthy subjects. The signal-to-noise-ratio (SNR) and the variance in metabolite amplitude between averages were measured for: (i) global versus local power optimization; (ii) static magnetic field (B0 ) shimming performed during free-breathing or within breathholds; (iii) post R-wave peak measurement times between 50 and 900 ms; (iv) without respiratory compensation, with breathholds and with navigator triggering; and (v) frequency selective excitation, Chemical Shift Selective (CHESS) and Multiply Optimized Insensitive Suppression Train (MOIST) water suppression techniques. Using the optimized parameters intra- and intersession myocardial triglyceride content reproducibility was measured. Two cardiac proton spectra were acquired with the same parameters and compared (intrasession reproducibility) after which the subject was removed from the scanner and placed back in the scanner and a third spectrum was acquired which was compared with the first measurement (intersession reproducibility). Local power optimization increased SNR on average by 22% compared with global power optimization (P = 0.0002). The average linewidth was not significantly different for pencil beam B0 shimming using free-breathing or breathholds (19.1 Hz versus 17.5 Hz; P = 0.15). The highest signal stability occurred at a cardiac trigger delay around 240 ms. The mean amplitude variation was significantly lower for breathholds versus free-breathing (P = 0.03) and for navigator triggering versus free-breathing (P = 0.03) as well as for navigator triggering versus breathhold (P = 0.02). The mean residual water signal using CHESS (1.1%, P = 0.01) or MOIST (0.7%, P = 0.01) water suppression was significantly lower than using frequency selective excitation water suppression (7.0%). Using the optimized parameters an intrasession limits of agreement of the myocardial triglyceride content of -0.11% to +0.04%, and an intersession of -0.15% to +0.9%, were achieved. The coefficient of variation was 5% for the intrasession reproducibility and 6.5% for the intersession reproducibility. Using approaches designed to optimize SNR and minimize the variation in inter-average signal intensities and frequencies/phases, a protocol was developed to perform cardiac MR spectroscopy on a clinical 3T system with high reproducibility. J. Magn. Reson. Imaging 2016;44:1151-1158.