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Abstract Aims Heart failure (HF) is frequent in patients with acute ischaemic stroke (AIS) and associated with higher morbidity and mortality. Assessment of cardiac function in AIS patients using cardiovascular MRI (CMR) may help to detect HF. We report the rate of systolic and diastolic dysfunction in a cohort of patients with AIS using CMR and compare cine real‐time (CRT) sequences with the reference of segmented cine steady‐state free precession sequences. Methods and results Patients with AIS without known atrial fibrillation were prospectively enrolled in the HEart and BRain Interfaces in Acute Ischemic Stroke (HEBRAS) study (NCT 02142413) and underwent CMR at 3 Tesla within 7 days after AIS. Validity of CRT sequences was determined in 50 patients. A total of 229 patients were included in the analysis (mean age 66 years; 35% women; HF 2%). Evaluation of cardiac function was successful in 172 (75%) patients. Median time from stroke onset to CMR was 82 h (interquartile range 56–111) and 54 h (interquartile range 31–78) from cerebral MRI to CMR. Systolic dysfunction was observed in 43 (25%) and diastolic dysfunction in 102 (59%) patients. Diagnostic yield was similar using CRT or segmented cine imaging (no significant difference in left ventricular ejection fraction, myocardial mass, time to peak filling rate, and peak filling rate ratio E/A). Intraobserver and interobserver agreement was high (κ = 0.78–1.0 for all modalities). Conclusions Cardiovascular MRI at 3 Tesla is an appropriate method for the evaluation of cardiac function in a selected cohort of patients with AIS. Systolic and diastolic dysfunction is frequent in these patients. CRT imaging allows reliable assessment of systolic and diastolic function.

Aims: Heart failure (HF) is frequent in patients with acute ischaemic stroke (AIS) and associated with higher morbidity and mortality. Assessment of cardiac function in AIS patients using cardiovascular MRI (CMR) may help to detect HF. We report the rate of systolic and diastolic dysfunction in a cohort of patients with AIS using CMR and compare cine real‐time (CRT) sequences with the reference of segmented cine steady‐state free precession sequences. Methods and results: Patients with AIS without known atrial fibrillation were prospectively enrolled in the HEart and BRain Interfaces in Acute Ischemic Stroke (HEBRAS) study (NCT 02142413) and underwent CMR at 3 Tesla within 7 days after AIS. Validity of CRT sequences was determined in 50 patients. A total of 229 patients were included in the analysis (mean age 66 years; 35% women; HF 2%). Evaluation of cardiac function was successful in 172 (75%) patients. Median time from stroke onset to CMR was 82 h (interquartile range 56–111) and 54 h (interquartile range 31–78) from cerebral MRI to CMR. Systolic dysfunction was observed in 43 (25%) and diastolic dysfunction in 102 (59%) patients. Diagnostic yield was similar using CRT or segmented cine imaging (no significant difference in left ventricular ejection fraction, myocardial mass, time to peak filling rate, and peak filling rate ratio E/A). Intraobserver and interobserver agreement was high (κ = 0.78–1.0 for all modalities). Conclusions: Cardiovascular MRI at 3 Tesla is an appropriate method for the evaluation of cardiac function in a selected cohort of patients with AIS. Systolic and diastolic dysfunction is frequent in these patients. CRT imaging allows reliable assessment of systolic and diastolic function. [ABSTRACT FROM AUTHOR]

Purpose: To validate an optimal 12‐fold accelerated real‐time cine MRI pulse sequence with radial k‐space sampling and compressed sensing (CS) in patients at 1.5T and 3T. Methods: We used two strategies to reduce image artifacts arising from gradient delays and eddy currents in radial k‐space sampling with balanced steady‐state free precession readout. We validated this pulse sequence against a standard breath‐hold cine sequence in two patient cohorts: a myocardial infarction (n = 16) group at 1.5T and chronic kidney disease group (n = 18) at 3T. Two readers independently performed visual analysis of 68 cine sets in four categories (myocardial definition, temporal fidelity, artifact, noise) on a 5‐point Likert scale (1 = nondiagnostic, 2 = poor, 3 = adequate or moderate, 4 = good, 5 = excellent). Another reader calculated left ventricular (LV) functional parameters, including ejection fraction. Results: Compared with standard cine, real‐time cine produced nonsignificantly different visually assessed scores, except for the following categories: 1) temporal fidelity scores were significantly lower (P = 0.013) for real‐time cine at both field strengths, 2) artifacts scores were significantly higher (P = 0.013) for real‐time cine at both field strengths, and 3) noise scores were significantly (P = 0.013) higher for real‐time cine at 1.5T. Standard and real‐time cine pulse sequences produced LV functional parameters that were in good agreement (e.g., absolute mean difference in ejection fraction <4%). Conclusion: This study demonstrates that an optimal 12‐fold, accelerated, real‐time cine MRI pulse sequence using radial k‐space sampling and CS produces good to excellent visual scores and relatively accurate LV functional parameters in patients at 1.5T and 3T. Magn Reson Med 79:2745–2751, 2018. © 2017 International Society for Magnetic Resonance in Medicine. [ABSTRACT FROM AUTHOR]

Background: Abnormalities of the cardiovascular system are the most common congenital diseases in the fetus and the first cause of infant mortality. Echocardiography is still the method of choice to visualize the fetal cardiac cardiovascular abnormalities, yet cardiovascular magnetic resonance (CMR) is relatively unaffected by maternal and fetal conditions such as maternal obesity, uterine myoma, twins, oligohydramnios, fetal position and rib calcification, which particularly impair sonographic visualization of the fetal heart. Fetal cardiac MR imaging is a novel MRI technique which can provide valuable information that could add to the prenatal diagnosis and evaluation of cardiac and most of extra-cardiac anomalies. In this work, we aimed to highlight the advantage of FCMRI over fetal echocardiography in assessment of fetal congenital cardiac anomalies. Results: Fifty-Two fetuses with suspected or diagnosed congenital cardiac anomalies. All cases underwent detailed history taking, underwent fetal echocardiography using suitable curvilinear probe and performed according to standard protocol, then fetal cardiac MR was done with Balanced fast field echo, Black blood single shot, white blood Cine, Real-time 3D dynamic sequences, images were acquired in the transverse, four-chamber, short-axis, coronal and oblique sagittal views. Findings of fetal echocardiography were compared with that of cardiac MRI and with standard post-natal echocardiography. Prenatal Echo and fetal cardiac MRI showed significant moderate agreement between the two modalities in the detection of different congenital cardiac anomalies, Kappa test: 0.500; p value 0.021. Fetal MRI had a significant role in detection of extra cardiac anomalies in most cases. Comparing to gold standard post-natal echo. Accuracy of fetal CMRI is 95.5% and of fetal Echo is 86.4% regarding overall cardiac anomalies: Conclusion: Fetal cardiac MR imaging as an adjunct to fetal echocardiography may provide valuable information that could add to the prenatal diagnosis and evaluation of cardiac and most of extra cardiac anomalies. [ABSTRACT FROM AUTHOR]

Objectives: The magnetic resonance (MR) 4D flow imaging–derived left atrial (LA) acceleration factor α was recently introduced as a means to non-invasively estimate LA pressure. We aimed to investigate the association of α with the severity of left ventricular (LV) diastolic dysfunction using echocardiography as the reference method. Methods: Echocardiographic assessment of LV diastolic function and 3-T cardiac MR 4D flow imaging were prospectively performed in 94 subjects (44 male/50 female; mean age, 62 ± 12 years). LA early diastolic peak outflow velocity (vE), systolic peak inflow velocity (vS), and early diastolic peak inflow velocity (vD) were evaluated from 4D flow data. α was calculated from α = vE / [(vS + vD) / 2]. Mean parameter values were compared by t-test; diagnostic performance of α in predicting diastolic (dys)function was investigated by receiver operating characteristic curve analysis. Results: Mean α values were 1.17 ± 0.14, 1.20 ± 0.08, 1.33 ± 0.15, 1.77 ± 0.18, and 2.79 ± 0.69 for grade 0 (n = 51), indeterminate (n = 9), grade I (n = 13), grade II (n = 13), and grade III (n = 8) LV diastolic (dys)function, respectively. α differed between subjects with non-advanced (grade < II) and advanced (grade ≥ II) diastolic dysfunction (1.20 ± 0.15 vs. 2.16 ± 0.66, p < 0.001). The area under the curve (AUC) for detection of advanced diastolic dysfunction was 0.998 (95% CI: 0.958–1.000), yielding sensitivity of 100% (95% CI: 84–100%) and specificity of 99% (95% CI: 93–100%) at cut-off α ≥ 1.58. The AUC for differentiating grade III diastolic dysfunction was also 0.998 (95% CI: 0.976–1.000) at cut-off α ≥ 2.14. Conclusion: The 4D flow–derived LA acceleration factor α allows grade II and grade III diastolic dysfunction to be distinguished from non-advanced grades as well as from each other. Clinical relevance statement: As a single continuous parameter, the 4D flow–derived LA acceleration factor α shows potential to simplify the multi-parametric imaging algorithm for diagnosis of advanced LV diastolic dysfunction, thereby identifying patients at increased risk for cardiovascular events. Key Points: • Detection of advanced diastolic dysfunction is typically performed using a complex, multi-parametric approach. • The 4D flow–derived left atrial acceleration factor α alone allows accurate detection of advanced left ventricular diastolic dysfunction. • As a single continuous parameter, the left atrial acceleration factor α could simplify the diagnosis of advanced diastolic dysfunction. [ABSTRACT FROM AUTHOR]

Objectives: To analyze alterations in left ventricular (LV) myocardial T1 times in patients with pulmonary hypertension (PH) and to investigate their associations with ventricular function, mass, geometry and hemodynamics.Methods: Fifty-eight patients with suspected PH underwent right heart catheterization (RHC) and 3T cardiac magnetic resonance imaging. Ventricular function, geometry and mass were derived from cine real-time short-axis images. Myocardial T1 maps were acquired by a prototype modified Look-Locker inversion-recovery sequence in short-axis orientations. LV global, segmental and ventricular insertion point (VIP) T1 times were evaluated manually and corrected for blood T1.Results: Septal, lateral, global and VIP T1 times were significantly higher in PH than in non-PH subjects (septal, 1249 ± 58 ms vs. 1186 ± 33 ms, p < 0.0001; lateral, 1190 ± 45 ms vs. 1150 ± 33 ms, p = 0.0003; global, 1220 ± 52 ms vs. 1171 ± 29 ms, p < 0.0001; VIP, 1298 ± 78 ms vs. 1193 ± 31 ms, p < 0.0001). In PH, LV eccentricity index was the strongest linear predictor of VIP T1 (r = 0.72). Septal, lateral and global T1 showed strong correlations with VIP T1 (r = 0.81, r = 0.59 and r = 0.75, respectively).Conclusions: In patients with PH, T1 times in VIPs and in the entire LV myocardium are elevated. LV eccentricity strongly correlates with VIP T1 time, which in turn is strongly associated with T1 time changes in the entire LV myocardium.Key Points: • Native T1 mapping detects left ventricular myocardial alterations in pulmonary hypertension • In pulmonary hypertension, native T1 times at ventricular insertion points are increased • These T1 times correlate strongly with left ventricular eccentricity • In pulmonary hypertension, global and segmental myocardial T1 times are increased • Global, segmental and ventricular insertion point T1 times are strongly correlated. [ABSTRACT FROM AUTHOR]

This document discusses the findings of a study on the use of PCD CT in ultra-high-resolution CCTA. The study found that higher temporal resolution improved image quality and reduced motion artifacts, which is important for accurate diagnosis and assessment of coronary artery disease. The document provides information for radiologists on the importance of evaluating coronary plaques on CT scans and emphasizes the need for appropriate indications for coronary CT angiography. It also mentions potential limitations and artifacts associated with CT scans and highlights the importance of performing high-quality examinations for optimal diagnostic accuracy. [Extracted from the article]

Purpose: Exercise‐induced dyspnea caused by lung water is an early heart failure symptom. Dynamic lung water quantification during exercise is therefore of interest to detect early stage disease. This study developed a time‐resolved 3D MRI method to quantify transient lung water dynamics during rest and exercise stress. Methods: The method was evaluated in 15 healthy subjects and 2 patients with heart failure imaged in transitions between rest and exercise, and in a porcine model of dynamic extravascular lung water accumulation through mitral regurgitation (n = 5). Time‐resolved images were acquired at 0.55T using a continuous 3D stack‐of‐spirals proton density weighted sequence with 3.5 mm isotropic resolution, and derived using a motion corrected sliding‐window reconstruction with 90‐s temporal resolution in 20‐s increments. A supine MRI‐compatible pedal ergometer was used for exercise. Global and regional lung water density (LWD) and percent change in LWD (ΔLWD) were automatically quantified. Results: A ΔLWD increase of 3.3 ± 1.5% was achieved in the animals. Healthy subjects developed a ΔLWD of 7.8 ± 5.0% during moderate exercise, peaked at 16 ± 6.8% during vigorous exercise, and remained unchanged over 10 min at rest (−1.4 ± 3.5%, p = 0.18). Regional LWD were higher posteriorly compared the anterior lungs (rest: 33 ± 3.7% vs 20 ± 3.1%, p < 0.0001; peak exercise: 36 ± 5.5% vs 25 ± 4.6%, p < 0.0001). Accumulation rates were slower in patients than healthy subjects (2.0 ± 0.1%/min vs 2.6 ± 0.9%/min, respectively), whereas LWD were similar at rest (28 ± 10% and 28 ± 2.9%) and peak exercise (ΔLWD 17 ± 10% vs 16 ± 6.8%). Conclusion: Lung water dynamics can be quantified during exercise using continuous 3D MRI and a sliding‐window image reconstruction. [ABSTRACT FROM AUTHOR]

Fetal magnetic resonance imaging (fetal MRI) is usually performed as a second-level examination following routine ultrasound examination, generally exploiting morphological and diffusion MRI sequences. The objective of this review is to describe the novelties and new applications of fetal MRI, focusing on three main aspects: the new sequences with their applications, the transition from 1.5-T to 3-T magnetic field, and the new applications of artificial intelligence software. This review was carried out by consulting the MEDLINE references (PubMed) and including only peer-reviewed articles written in English. Among the most important novelties in fetal MRI, we find the intravoxel incoherent motion model which allow to discriminate the diffusion from the perfusion component in fetal and placenta tissues. The transition from 1.5-T to 3-T magnetic field allowed for higher quality images, thanks to the higher signal-to-noise ratio with a trade-off of more frequent artifacts. The application of motion-correction software makes it possible to overcome movement artifacts by obtaining higher quality images and to generate three-dimensional images useful in preoperative planning. Relevance statement This review shows the latest developments offered by fetal MRI focusing on new sequences, transition from 1.5-T to 3-T magnetic field and the emerging role of AI software that are paving the way for new diagnostic strategies. Key points • Fetal magnetic resonance imaging (MRI) is a second-line imaging after ultrasound. • Diffusion-weighted imaging and intravoxel incoherent motion sequences provide quantitative biomarkers on fetal microstructure and perfusion. • 3-T MRI improves the detection of cerebral malformations. • 3-T MRI is useful for both body and nervous system indications. • Automatic MRI motion tracking overcomes fetal movement artifacts and improve fetal imaging. [ABSTRACT FROM AUTHOR]

Objective: This study combines a deep image prior with low-rank subspace modeling to enable real-time (free-breathing and ungated) functional cardiac imaging on a commercial 0.55 T scanner. Materials and methods: The proposed low-rank deep image prior (LR-DIP) uses two u-nets to generate spatial and temporal basis functions that are combined to yield dynamic images, with no need for additional training data. Simulations and scans in 13 healthy subjects were performed at 0.55 T and 1.5 T using a golden angle spiral bSSFP sequence with images reconstructed using l 1 -ESPIRiT, low-rank plus sparse (L + S) matrix completion, and LR-DIP. Cartesian breath-held ECG-gated cine images were acquired for reference at 1.5 T. Two cardiothoracic radiologists rated images on a 1–5 scale for various categories, and LV function measurements were compared. Results: LR-DIP yielded the lowest errors in simulations, especially at high acceleration factors (R ≥ 8). LR-DIP ejection fraction measurements agreed with 1.5 T reference values (mean bias − 0.3% at 0.55 T and − 0.2% at 1.5 T). Compared to reference images, LR-DIP images received similar ratings at 1.5 T (all categories above 3.9) and slightly lower at 0.55 T (above 3.4). Conclusion: Feasibility of real-time functional cardiac imaging using a low-rank deep image prior reconstruction was demonstrated in healthy subjects on a commercial 0.55 T scanner. [ABSTRACT FROM AUTHOR]

Abstract Background Abnormalities of the cardiovascular system are the most common congenital diseases in the fetus and the first cause of infant mortality. Echocardiography is still the method of choice to visualize the fetal cardiac cardiovascular abnormalities, yet cardiovascular magnetic resonance (CMR) is relatively unaffected by maternal and fetal conditions such as maternal obesity, uterine myoma, twins, oligohydramnios, fetal position and rib calcification, which particularly impair sonographic visualization of the fetal heart. Fetal cardiac MR imaging is a novel MRI technique which can provide valuable information that could add to the prenatal diagnosis and evaluation of cardiac and most of extra-cardiac anomalies. In this work, we aimed to highlight the advantage of FCMRI over fetal echocardiography in assessment of fetal congenital cardiac anomalies. Results Fifty-Two fetuses with suspected or diagnosed congenital cardiac anomalies. All cases underwent detailed history taking, underwent fetal echocardiography using suitable curvilinear probe and performed according to standard protocol, then fetal cardiac MR was done with Balanced fast field echo, Black blood single shot, white blood Cine, Real-time 3D dynamic sequences, images were acquired in the transverse, four-chamber, short-axis, coronal and oblique sagittal views. Findings of fetal echocardiography were compared with that of cardiac MRI and with standard post-natal echocardiography. Prenatal Echo and fetal cardiac MRI showed significant moderate agreement between the two modalities in the detection of different congenital cardiac anomalies, Kappa test: 0.500; p value 0.021. Fetal MRI had a significant role in detection of extra cardiac anomalies in most cases. Comparing to gold standard post-natal echo. Accuracy of fetal CMRI is 95.5% and of fetal Echo is 86.4% regarding overall cardiac anomalies: Conclusion Fetal cardiac MR imaging as an adjunct to fetal echocardiography may provide valuable information that could add to the prenatal diagnosis and evaluation of cardiac and most of extra cardiac anomalies.

Aims Inefficient ventricular–arterial (V–A) coupling has been described in Fontan patients and may result in adverse haemodynamics. A varying amount of aortopulmonary collateral (APC) flow is also frequently present that increases volume load of the single ventricle. The aim of the study was to assess changes in V–A coupling and APC flow during exercise CMR. Methods and results Eighteen Fontan patients (age 24 ± 3 years) and 14 controls (age 23 ± 4 years) underwent exercise CMR using a cycle ergometer. Ventricular volumetry and flow measurements in the ascending aorta (AAO), inferior (IVC), and superior (SVC) vena cava were assessed using real-time sequences during stepwise increases in work load. Measures of systemic arterial elastance Ea, ventricular elastance Ees, and V–A coupling (Ea/Ees) were assessed. APC flow was quantified as AAO − (SVC + IVC). Ea remained unchanged during all levels of exercise in both groups (P = 0.39 and P = 0.11). Ees increased in both groups (P = 0.001 and P < 0.001) with exercise but was lower in the Fontan group (P = 0.04). V–A coupling was impaired in Fontan patients at baseline (P = 0.04). Despite improvement during exercise (P = 0.002) V–A coupling remained impaired compared with controls (P = 0.001). Absolute APC flow in Fontan patients did not change during exercise even at maximum work load (P = 0.98). Conclusions Inefficient V–A coupling was already present at rest in Fontan patients and aggravated during exercise due to a limited increase in ventricular contractility which demonstrates the importance of a limited functional reserve of the single ventricle. APC flow remained unchanged suggesting no further increase in volume load during exercise. [ABSTRACT FROM AUTHOR]

Objective. Cardiovascular magnetic resonance (CMR) can measure ventricular volumes for the quantitative assessment of cardiac function in clinical cardiology. Conventionally, CMR volumetric measurements require image reconstruction and segmentation. There are limited clinical applications of real-time CMR for volumetric measurements because real-time images cannot provide sufficient quality for accurate segmentation. The presented work aims to develop a new deep learning approach to measuring ventricular volumes without image reconstruction and demonstrate that this ‘imageless’ approach would improve volumetric measurements with real-time CMR. Approach. We have developed a deep learning model for measuring ventricular volumes directly from real-time CMR raw data without image reconstruction. This novel ‘imageless’ deep learning model, not being as sensitive to image quality, provided reliable volumetric measurements for real-time CMR. To demonstrate ‘imageless’ volumetric measurements, we conducted a real-time CMR study with healthy volunteers. Several performance metrics, including mean absolute error (MAE), the Pearson correlation coefficient, and Blandâ€"Altman analysis, were used to evaluate the proposed ‘imageless’ deep learning model in reference to U-net and fully convolutional neural network (FCNN) models based on conventional image reconstruction and segmentation. Main results. With the same raw data, the ‘imageless’ deep learning model gave a lower MAE (‘imageless’ ≤9.6 ml; ‘image-based’ ≥12.1 ml), a higher correlation coefficient (‘imageless’ ≥0.75; ‘image-based’ ≤0.51) and smaller measurement difference ranges in Blandâ€"Altman analysis (‘imageless’ ≤23.1 ml; ‘image-based’ ≥33.8 ml). To achieve comparable performance, the ‘imageless’ deep learning model needed 2/3 of the raw data used in image reconstruction for U-net and FCNN models, indicating there was a gain in imaging acceleration for real-time CMR. Significance. We have demonstrated a novel deep learning framework that can provide reliable volumetric measurements from real-time CMR raw data without image reconstruction. This ‘imageless’ approach to real-time volumetric measurements will improve the quantitative assessment of cardiac function in clinical cardiology. [ABSTRACT FROM AUTHOR]

Purpose: This work proposes principal component analysis (PCA) coil compression and weight sharing to reduce acquisition and reconstruction time of through‐time radial GRAPPA. Methods: Through‐time radial GRAPPA enables ungated free‐breathing motion‐resolved cardiac imaging but requires a long calibration acquisition and GRAPPA weight calculation time. PCA coil compression reduces calibration data requirements and associated acquisition time, and weight sharing reduces the number of unique GRAPPA weight sets and associated weight computation time. In vivo cardiac data reconstructed with coil compression and weight sharing are compared to a gold standard to demonstrate improvement in calibration acquisition and reconstruction performance with minimal loss of image quality. Results: Coil compression from 30 physical to 12 virtual coils (90% of signal variance) decreases requisite calibration data by 60%, reducing calibration acquisition time to 6.7 s/slice from 31.5 s/slice reported in original through‐time radial GRAPPA work. Resulting images have small increase in RMS error (RMSE). Reconstruction with a weight sharing factor of 8 results in eight‐fold reduction in GRAPPA weight calculation time with a comparable RMSE to reconstructions with no weight sharing. Optimized parameters for coil compression and weight sharing applied to reconstructions enables images to be collected with a temporal resolution of 66 ms/frame and spatial resolution of 2.34 × 2.34 mm while reducing calibration acquisition time from 34 to 6.7 s, weight calculation time from 200 to 3 s, and weight application time 18 to 5 s. Conclusion: Coil compression and weight sharing applied to through‐time radial GRAPPA enables fast free‐breathing ungated cardiac cine without compromising image quality. [ABSTRACT FROM AUTHOR]

The purpose of the current study was to implement and validate joint real‐time acquisition of functional and late gadolinium‐enhancement (LGE) cardiac magnetic resonance (MR) images during free breathing. Inversion recovery cardiac real‐time images with a temporal resolution of 50 ms were acquired using a spiral trajectory (IR‐CRISPI) with a pre‐emphasis based on the gradient system transfer function during free breathing. Functional and LGE cardiac MR images were reconstructed using a low‐rank plus sparse model. Late gadolinium‐enhancement appearance, image quality, and functional parameters of IR‐CRISPI were compared with clinical standard balanced steady‐state free precession breath‐hold techniques in 10 patients. The acquisition of IR‐CRISPI in free breathing of the entire left ventricle took 97 s on average. Bland–Altman analysis and Wilcoxon tests showed a higher artifact level for the breath‐hold technique (p = 0.003), especially for arrhythmic patients or patients with dyspnea, but an increased noise level for IR‐CRISPI of the LGE images (p = 0.01). The estimated transmural extent of the enhancement differed by not more than 25% and did not show a significant bias between the techniques (p = 0.50). The ascertained functional parameters were similar for the breath‐hold technique and IR‐CRISPI, that is, with a minor, nonsignificant (p = 0.16) mean difference of the ejection fraction of 2.3% and a 95% confidence interval from −4.8% to 9.4%. IR‐CRISPI enables joint functional and LGE imaging in free breathing with good image quality but distinctly shorter scan times in comparison with breath‐hold techniques. [ABSTRACT FROM AUTHOR]

Cardiac magnetic resonance imaging (MRI) has been largely dependent on retrospective cine for data acquisition. Real-time imaging, although inferior in image quality to retrospective cine, is more informative about motion dynamics. We herein developed a real-time cardiac MRI approach to temporospatial characterization of left ventricle (LV) and right ventricle (RV) wall motion. This approach provided two temporospatial indices, temporal periodicity and spatial coherence, for quantitative assessment of ventricular function. In a cardiac MRI study, we prospectively investigated temporospatial characterization in reference to standard volumetric measurements with retrospective cine. The temporospatial indices were found to be effective for evaluating the difference of ventricular performance between the healthy volunteers and the heart failure (HF) patients (LV temporal periodicity 0.24 ± 0.037 vs. 0.14 ± 0.021; RV temporal periodicity 0.18 ± 0.030 vs. 0.10 ± 0.014; LV spatial coherence 0.52 ± 0.039 vs. 0.38 ± 0.040; RV spatial coherence 0.50 ± 0.036 vs. 0.35 ± 0.035; all in arbitrary unit). The HF patients and healthy volunteers were well differentiated in the scatter plots of spatial coherence and temporal periodicity while they were mixed in those of end-systolic volume (ESV) and ejection fraction (EF) from volumetric measurements. This study demonstrated the potential of real-time cardiac MRI for intricate analysis of ventricular function beyond retrospective cine. [ABSTRACT FROM AUTHOR]

Purpose: To analyze differences in systolic and diastolic left ventricular (LV) as well as left atrial (LA) function parameters obtained from identical cardiac magnetic resonance (MR) imaging techniques during inspiratory breath-holding and breathing (breath-hold to breathing differences).Method: 56 subjects without signs of heart failure (23/33 male/female, age 58 ± 14 years) underwent 3 T MR cine real-time and transmitral phase contrast imaging with the same spatial and temporal resolution during inspiratory breath-holding and free breathing. LV and LA volumetric function parameters were derived from segmentation of cine series, transmitral peak velocities and early-diastolic myocardial peak velocity from phase contrast series. Corresponding breath-hold and breathing parameters were compared by Bland-Altman analysis; repeatability of breath-hold and breathing measurements was quantified by variance component analysis. p < 0.05 was regarded as statistically significant.Results: Mean differences between results obtained during inspiratory breath-holding vs. breathing were significant for LV volumetric function (end-diastolic volume=-7 mL, p = 0.002; end-systolic volume=-7 mL, p < 0.001; ejection fraction = 3 %, p < 0.001; peak ejection rate = 22 mL/s, p = 0.002; early-diastolic peak filling rate=-34 mL/s, p = 0.025), LA volumetric function (maximum volume=-6 mL, p < 0.001; total ejection fraction=-4%, p < 0.001; active ejection fraction=-2%, p = 0.013; before contraction ejection fraction=-4%, p < 0.001) and early-diastolic velocities (transmitral=-6 cm/s, p < 0.001; tissue velocity=-1.8 cm/s, p < 0.001). Standard deviations of breath-hold-to-breathing differences exceeded the corresponding repeatabilities of breath-hold and breathing measurements.Conclusions: Systolic and diastolic LV and LA function parameters acquired during inspiratory breath-holding and breathing differ, and large inter-individual breath-hold-to-breathing variations are possible. Thus, the breathing state should be taken into account, especially when comparing results in patient follow-up acquired in different respiratory states. [ABSTRACT FROM AUTHOR]

A challenge when repairing imperforate anus is positioning the neo-rectum into the center of the sphincter muscle complex (SMC) with limited muscle injury and scarring. Unfortunately, the path through the components of the SMC are often non-linear. We have used MRI to delineate the complex and guide the needle through the center using standard MRI-guidance (Raschbaum GR et al. J Pediatr Surg 45:220-223, 2010; Thomas TT et al. J Pediatr Surg 35:927–930, 2000). However, asynchronous scanning requires multiple, time-consuming scans to advance the needle in stepwise fashion. Asynchronous scanning also prevents visualizing the needle as it is advanced. We recently integrated software into the MRI operative suite that allows placement of the needle with real-time MRI. We report the feasibility and utility of real-time MRI-assisted laparoscopic assisted anorectoplasty (RT MRI-LAARP). Needle guidance was performed with Siemens Espree 1.5 T MRI with T1 Flash RT Sequence. After needle placement, laparoscopic mobilization, fistula takedown and pull-through was performed using the needle to guide dilation to create a tract to pull-through the neo-rectum. Charts of patients who underwent RT MRI-LAARP were reviewed. Demographics, anatomy, number of needle passes, OR duration and complications are reported. There were five children that underwent RT MRI-LAARP; one was a redo secondary to a retracted rectovestibular fistula. Operative time ranged from 187–505 min. Average hospital stay was 4.0 ± 1.0 days. There were no intraoperative complications although one patient had temporary urinary retention post-op. Muscle sparring laparoscopic anorectoplasty using real-time MRI is feasible and facilitates needle placement through the SMC. [ABSTRACT FROM AUTHOR]

Pericardial abnormalities are common cardiovascular disease entity, which are encountered in various clinical settings. Imaging plays an integral role in evaluation of pericardial abnormalities. The appropriate use of multiple imaging modalities is crucial to initiate the diagnosis and guide the referring providers to establish a management plan. Echocardiography (echo) is the initial imaging modality of choice. Computed tomography (CT) and magnetic resonance imaging (MRI) are complementary imaging tools with better tissue characterization. Pericardial abnormalities include pericardial effusion, pericarditis, pericardial constriction, tamponade, pneumopericardium, pericardial rupture, fistulas, congenital abnormalities, and pericardial tumors. Pericardial effusion is a common clinical entity, where there is accumulation of fluid in the pericardial sac. Pericarditis can be acute, incessant, chronic, or recurrent. Pericardial thickening or enhancement are the main CT findings in acute pericarditis. Pericardial constriction results into diastolic heart failure. Differentiating constrictive pericarditis from restrictive cardiomyopathy is important, since these conditions can present with similar clinical and hemodynamic findings and both have different management. Right atrial or right ventricular compression by the pericardial sac contents should raise the suspicion for tamponade. Immediate pericardiocentesis to release the elevated intra-pericardial pressure can be lifesaving. Pericardial rupture is a serious condition that can occur after trauma and can lead to cardiac herniation. The main purpose of this article is to do a comprehensive review of the imaging appearance of pericardial diseases on different imaging modalities and establish a structured diagnostic approach for pericardial diseases to appropriately guide management. [ABSTRACT FROM AUTHOR]

Thoracic MRI presents important and unique challenges. Decreased proton density in the lung in combination with respiratory and cardiac motion can degrade image quality and render poorly executed sequences uninterpretable. Despite these challenges, thoracic MRI has an important clinical role, both as a problem-solving tool and in an increasing array of clinical indications. Advances in scanner and sequence design have also helped to drive this development, presenting the radiologist with improved techniques for thoracic MRI. Given this evolving landscape, radiologists must be familiar with what thoracic MR has to offer. The first step in developing an effective thoracic MRI practice requires the creation of efficient and malleable protocols that can answer clinical questions. To do this, radiologists must have a working knowledge of the MR sequences that are used in the thorax, many of which have been adapted from use elsewhere in the body. These sequences can be broadly divided into three categories: traditional/anatomic, functional, and cine based. Traditional/anatomic sequences allow for the depiction of anatomy and pathologic processes with the ability for characterization of signal intensity and contrast enhancement. Functional sequences, including diffusion-weighted imaging, and high temporal resolution dynamic contrast enhancement, allow for the noninvasive measurement of tissue-specific parameters. Cine-based sequences can depict the motion of structures in the thorax, either with retrospective ECG gating or in real time. The purpose of this article is to review these categories, the building block sequences that comprise them, and identify basic questions that should be considered in thoracic MRI protocol design. Level of Evidence: 5 Technical Efficacy Stage: 3 J. Magn. Reson. Imaging 2019;50:682-701. [ABSTRACT FROM AUTHOR]

Congenital and acquired airway anomalies represent a relatively common albeit diagnostic and therapeutic challenge, even for the most skilled operators in dedicated centers. Airway malformations encompass a wide spectrum of pathologies involving the larynx, trachea and bronchi, esophagus, mediastinal vessels. These developmental lesions are often isolated but the association of two or more anomalies is not infrequent. From the traditional chest X-ray to the newest applications of Optical Coherence Tomography, non- or mini-invasive diagnostic techniques represent useful tools to integrate invasive procedures. Comprehensive knowledge of the characteristics of each diagnostic test is mandatory for its useful application. The aim of our paper is to analyze the clinical indications for Imaging the Airway disease in pediatric population, and describe the diagnostic techniques. Only by a close interaction between all the operators involved in diagnosis and treatment of pediatric airway, as it happens in Multidisciplinary Airway Team, the non- or mini-invasive imaging is effective. [ABSTRACT FROM AUTHOR]

The article presents abstracts on medical topics which includes "Is there space for MDCT (spectral imaging, iodine map)?" by J. Podgorska, "Tuberculosis," by E. Castañer, and "Is sonography (CEUS and elastography) the right tool?" by E. Quaia.

Assessing left ventricular diastolic and regional function is a crucial part of the cardiovascular evaluation. Diastolic function is as important as systolic function for left ventricular performance because it is the determinant of the ability of the left atrium and ventricle to fill at relatively low pressures. Additionally, diastolic function plays an important role in the management and prognosis of patients with symptoms and signs of heart failure. Technical advances in the imaging modalities have allowed a comprehensive noninvasive assessment of global and regional cardiac mechanics and precise estimation of cardiovascular hemodynamics. In this review, we will discuss and compare clinically available techniques and novel approaches using echocardiography, cardiac magnetic resonance, and computed tomography for the assessment of diastolic and regional left ventricular function. [ABSTRACT FROM AUTHOR]

Objectives: Fetal cardiovascular magnetic resonance imaging (MRI) offers a potential alternative to echocardiography, although in practice, its use has been limited. We sought to explore the need for additional imaging in a tertiary fetal cardiology unit and the usefulness of standard MRI sequences.Methods: Cases where the diagnosis was not fully resolved using echocardiography were referred for MRI. Following a three-plane localiser, fetal movement was assessed with a balanced steady-state free precession (bSSFP) cine. Single-shot fast spin echo and bSSFP sequences were used for diagnostic imaging.Results: Twenty-two fetal cardiac MRIs were performed over 12 months, at mean gestation of 32 weeks (26-38 weeks). The majority of referrals were for suspected vascular abnormalities (17/22), particularly involving the aortic arch (n = 10) and pulmonary vessels (n = 4). Single-shot fast spin echo sequences produced 'black-blood' images, useful for examining the extracardiac vasculature in these cases. BSSFP sequences were more useful for intracardiac structures. Real-time SSFP allowed for dynamic assessment of structures such as cardiac masses, with enhancement patterns also allowing for tissue characterisation in these cases.Conclusions: Fetal vascular abnormalities such as coarctation can be difficult to diagnose by using ultrasound. Fetal MRI may have an adjunctive role in the evaluation of the extracardiac vascular anatomy and tissue characterisation. © 2016 The Authors. Prenatal Diagnosis published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article presents abstracts on medical topics including stroke risk and diagnosis of atrial fibrillation in patients with atrial septal defects, anatomic repair of congenitally corrected transposition of arteries in adults, and aortopathy assessment in bicuspid aortic valve disease.

Purpose For the application of compressive sensing to parallel MRI, Poisson disk sampling (PDS) has been shown to generate superior results compared with random sampling methods. However, due to its limited flexibility to incorporate additional constraints, PDS is not readily extendible to dynamic applications. Here, we propose and validate a pseudo-random sampling technique that allows incorporating constraints specific to dynamic imaging. Methods The proposed sampling scheme, called variable density incoherent spatiotemporal acquisition (VISTA), is based on constrained minimization of Riesz energy on a spatiotemporal grid. Data from both a digital phantom and real-time cine were used to compare VISTA with uniform interleaved sampling (UIS) and variable density random sampling (VRS). The image quality was assessed qualitatively and quantitatively. Results VISTA improved the trade-off between noise and sharpness. Also, VISTA produced diagnostic quality images at an acceleration rate of 15, whereas UIS and VRS images degraded below the diagnostic threshold at lower acceleration rates. Conclusions VISTA generates spatiotemporal sampling patterns with high levels of uniformity and incoherence, while maintaining a constant temporal resolution. Using a small pilot study, VISTA was shown to produce diagnostic quality images at acceleration rates up to 15. Magn Reson Med 74:1266-1278, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Purpose To evaluate a novel real-time phase-contrast magnetic resonance imaging (MRI) technique for the assessment of through-plane flow in the ascending aorta. Materials and Methods Real-time MRI was based on a radial fast low-angle shot (FLASH) sequence with about 30-fold undersampling and image reconstruction by regularized nonlinear inversion. Phase-contrast maps were obtained from two (interleaved or sequential) acquisitions with and without a bipolar velocity-encoding gradient. Blood flow in the ascending aorta was studied in 10 healthy volunteers at 3 T by both real-time MRI (15 sec during free breathing) and electrocardiogram (ECG)-synchronized cine MRI (with and without breath holding). Flow velocities and stroke volumes were evaluated using standard postprocessing software. Results The total acquisition time for a pair of phase-contrast images was 40.0 msec (TR/TE = 2.86/1.93 msec, 10° flip angle, 7 spokes per image) for a nominal in-plane resolution of 1.3 mm and a section thickness of 6 mm. Quantitative evaluations of spatially averaged flow velocities and stroke volumes were comparable for real-time and cine methods when real-time MRI data were averaged across heartbeats. For individual heartbeats real-time phase-contrast MRI resulted in higher peak velocities for values above 120 cm s−1. Conclusion Real-time phase-contrast MRI of blood flow in the human aorta yields functional parameters for individual heartbeats. When averaged across heartbeats real-time flow velocities and stroke volumes are comparable to values obtained by conventional cine MRI. J. Magn. Reson. Imaging 2014;40:206-213. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

For patients with impaired breath-hold capacity and/or arrhythmias, real-time cine MRI may be more clinically useful than breath-hold cine MRI. However, commercially available real-time cine MRI methods using parallel imaging typically yield relatively poor spatio-temporal resolution due to their low image acquisition speed. We sought to achieve relatively high spatial resolution (∼2.5 × 2.5 mm2) and temporal resolution (∼40 ms), to produce high-quality real-time cine MR images that could be applied clinically for wall motion assessment and measurement of left ventricular function. In this work, we present an eightfold accelerated real-time cardiac cine MRI pulse sequence using a combination of compressed sensing and parallel imaging (k-t SPARSE-SENSE). Compared with reference, breath-hold cine MRI, our eightfold accelerated real-time cine MRI produced significantly worse qualitative grades (1-5 scale), but its image quality and temporal fidelity scores were above 3.0 (adequate) and artifacts and noise scores were below 3.0 (moderate), suggesting that acceptable diagnostic image quality can be achieved. Additionally, both eightfold accelerated real-time cine and breath-hold cine MRI yielded comparable left ventricular function measurements, with coefficient of variation <10% for left ventricular volumes. Our proposed eightfold accelerated real-time cine MRI with k- t SPARSE-SENSE is a promising modality for rapid imaging of myocardial function. J. Magn. Reson. Imaging 2013. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The article discusses a study on single-heartbeat fast strain encoding (Fast-SENC) imaging for assessing right ventricular (RV) regional function in patients with pulmonary hypertension. Fast-SENC is designed to address the difficulty of making reliable RV function assessment using traditional breath-holding methods. The study involved 11 healthy volunteers and 11 patients with pulmonary hypertension. The study compared fast-SENC RV longitudinal strain and circumferential strain measurements to traditional SENC and MR tagging, respectively.

AbstractObjective??When performing epidural steroid injections for the management of chronic back pain, imaging guidance and a limited epidurogram improve accuracy of needle placement and ensure appropriate delivery of the injectate into the epidural space. We describe our experience using a gadolinium chelate as an alternative contrast agent for limited epidurography in patients with a history of an iodinated contrast reaction.Design??Thirty-eight of 2,067 (1.8%) epidural steroid injections performed in our department over a 25-month period (December 2003?January 2006) employed gadolinium. All injections were performed in the lumbar spine employing a paramedian interlaminar approach. Procedural notes and patient charts were reviewed to evaluate for immediate or delayed complications related to incorrect intrathecal or intravascular needle placement. A retrospective analysis of selected fluoroscopic spot images was performed to evaluate confidence of epidural needle placement; this analysis compared these spot images against those obtained from age- and gender-matched control patients in whom iodinated contrast was used to confirm needle placement.Results??Real-time fluoroscopic guidance permitted confident visualization of an epidurogram at the time of procedure in all 38 cases as documented in the procedural report, and no procedure resulted in a complication due to incorrect needle placement. Retrospective review of fluoroscopic spot images revealed at least moderate confidence of epidural needle placement by both readers in 29/38 cases (76.3%). Fluoroscopic spot images obtained using gadolinium yielded significantly less confidence than images obtained in control patients whose procedures were performed using iodinated contrast (P<0.01). However, operators were sufficiently confident in needle placement based on real-time fluoroscopic images (not available in our subsequent review) to inject anesthestic in all 38 cases, despite the immediate consequences that could result from intrathecal administration. During the same time period, there were 11/2,067 (0.5%) instances of intrathecal needle placement discovered during attempted epidurography despite the use of fluoroscopy for needle guidance and reliance on loss-of-resistance technique.Conclusion??Gadolinium chelate represents a safe and useful alternative contrast agent for confirmation of epidural needle placement in patients with an iodinated contrast allergy. [ABSTRACT FROM AUTHOR]

Steady-state free precession (SSFP) is a rapid gradient-echo imaging technique that has recently gained popularity and is used in a variety of applications, including cardiac and real-time imaging, because of its high signal and favorable contrast between blood and myocardium. The purpose of this work was to examine the signal-to-noise ratio (SNR) behavior of images acquired with SSFP, and the dependence of SNR on imaging parameters such as TR, bandwidth, and image resolution, and the use of multi-echo sequences. In this work it is shown that the SNR of SSFP sequences is dependent only on pulse sequence efficiency, voxel dimensions, and relaxation parameters ( T1 and T2). Notably, SNR is insensitive to bandwidth unless increases in bandwidth significantly decrease efficiency. Finally, we examined the relationship between pulse sequence performance (TR and efficiency) and gradient performance (maximum gradient strength and slew rate) for several imaging scenarios, including multi-echo sequences, to determine the optimum matching of maximum gradient strength and slew rate for gradient hardware designs. For standard modern gradient hardware (40 mT/m and 150 mT/m/ms), we found that the maximum gradient strength is more than adequate for the imaging resolution that is commonly encountered with rapid scouting (3 mm × 4 mm × 10 mm voxel). It is well matched for typical CINE and real-time cardiac imaging applications (1.5 mm × 2 mm × 6 mm voxel), and is inadequate for optimal matching with slew rate for high-resolution applications such as musculoskeletal imaging (0.5 × 0.8 × 3 mm voxel). For the lower-resolution methods, efficiency could be improved with higher slew rates; this provokes interest in designing methods for limiting dB/dt peripherally while achieving high switching rates in the imaging field of view. The use of multi-echo SSFP acquisitions leads to substantial improvements in sequence performance (i.e., increased efficiency and shorter TR). Magn Reson Med 52:123-130, 2004. Published 2004 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Purpose. To evaluate the accuracy of cardiac function measured with real-time true fast imaging with steady-state precession (True-FISP) cine without breath-hold compared with those measured from segmented True-FISP cine with breath-hold. Methods. Eighteen consecutive patients and six healthy volunteers were enrolled in the study group. Both real-time multislice True-FISP cine imaging without breath-hold and single-slice segmented True-FISP cine imaging with multiple breath-holds were performed in short-axis imaging sections to encompass the entire ventricles. Vertical long-axis cine imaging using real-time True-FISP cine sequence without breath-hold was performed to evaluate heart motion during respiration in 13 subjects. Ventricular volume and mass were evaluated by four observers independently with manual tracing. Results. Real-time True-FISP cine quality was sufficient for contour detection in all 24 subjects. Cardiodynamic measurements based on real-time True-FISP cine correlated well with those based on segmented True-FISP cine [left ventricular (LV) end-diastolic volume: r = 0.98; LV end-systolic volume: r = 0.98; LV ejection fraction: r = 0.91; LV mass: r = 0.96; right ventricular (RV) end-diastolic volume: r = 0.89; RV end-systolic volume: r = 0.94; RV ejection fraction: r = 0.79]. Intra- and interobserver variability were sufficiently small in real-time True-FISP cine without breath-hold. Heart motion during respiration along the long axis of the left ventricle (2.2 mm to 3.7 mm) was much less than the slice interval (10 mm), confirming that misregistration of slice position during respiration was low. Conclusion. Real-time True-FISP cine without breath-hold has high reproducibility and is applicable to patients with severe cardiac dysfunction and/or arrhythmias. [ABSTRACT FROM AUTHOR]

Background and objective: Real-time compressed sensing cine (CSrt) provides reliable quantification for both ventricles but may alter image quality. The aim of this study was to assess image quality and the accuracy of left (LV) and right ventricular (RV) volumes, ejection fraction and mass quantifications based on a retrogated segmented compressed sensing 2D cine sequence (CSrg). Methods: Thirty patients were enrolled. Each patient underwent the reference retrogated segmented steady-state free precession cine sequence (SSFPref), the real-time CSrt cine and the segmented retrogated prototype CSrg sequence providing the same slices. Functional parameters quantification and image quality rating were performed on SSFPref and CSrg images sets. The edge sharpness, which is an estimate of the edge spread function, was assessed for the three sequences. Results: The mean scan time was: SSFPref = 485.4 ± 83.3 (SD) s (95% CI: 454.3–516.5) and CSrg = 58.3 ± 15.1 (SD) s (95% CI: 53.7–64.2) (p < 0.0001). CSrg subjective image quality score (median: 4; range: 2–4) was higher than the one provided by CSrt (median: 3; range: 2–4; p = 0.0008) and not different from SSFPref overall quality score (median: 4; range: 2–4; p = 0.31). CSrg provided similar LV and RV functional parameters to those assessed with SSFPref (p > 0.05). Edge sharpness was significantly better with CSrg (0.083 ± 0.013 (SD) pixel−1; 95% CI: 0.078–0.087) than with CSrt (0.070 ± 0.011 (SD) pixel−1; 95% CI: 0.066–0.074; p = 0.0004) and not different from the reference technique (0.075 ± 0.016 (SD) pixel−1; 95% CI: 0.069–0.081; p = 0.0516). Conclusions: CSrg cine provides in one minute an accurate quantification of LV and RV functional parameters without compromising subjective and objective image quality. [ABSTRACT FROM AUTHOR]

The article presents abstracts on medical topics which include factors affecting the image quality of cardiac magnetic resonance imaging to patients with congenital heart disease, research on the accuracy of the look locker technique after surgery, and effect of cardiac iron to transfusion-dependent patients.