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Cardiac magnetic resonance (CMR) imaging is widely used in many areas of cardiovascular disease assessment. This is a practical, standard CMR protocol for beginners that is designed to be easy to follow and implement. This protocol guideline is based on previously reported CMR guidelines and includes sequence terminology used by vendors, essential MR physics, imaging planes, field strength considerations, MRI-conditional devices, drugs for stress tests, various CMR modules, and disease/symptom-based protocols based on a survey of cardiologists and various appropriate-use criteria. It will be of considerable help in planning and implementing tests. In addressing CMR usage and creating this protocol guideline, we particularly tried to include useful tips to overcome various practical issues and improve CMR imaging. We hope that this document will continue to standardize and simplify a patient-based approach to clinical CMR and contribute to the promotion of public health., Competing Interests: The authors have no potential conflicts of interest to disclose., (Copyright © 2019 The Korean Society of Radiology.)

Purpose To evaluate the effect of changes in hematocrit level on myocardial extracellular volume (ECV) fraction, as quantified with cardiac magnetic resonance (MR) imaging in an animal model. Materials and Methods Thirteen adult male Sprague-Dawley rats underwent cardiac MR imaging before and after induction of anemia. MR imaging procedures, including unenhanced and contrast material-enhanced T1 mapping, were performed by using a saturation recovery Look-Locker sequence with a 9.4-T unit. An optimized T1 mapping sequence was established in the phantom study. Systolic function of the left ventricle (LV) was calculated from the cine images. Native and postcontrast T1 values of the LV myocardium at the midcavity level and LV blood pool, partition coefficients, and ECV were calculated. Histopathologic examination of the heart was performed after sacrifice. Intergroup comparison of variables was performed with the paired t test. Results The postanemia models exhibited lower hematocrit levels, postcontrast T1 values of the LV pool, and partition coefficients (mean, 45.7% ± 5.2 [standard deviation]; 563.8 msec ± 155.7; and 29.2 ± 3.5, respectively) than did the preanemia models (mean, 59.0% ± 4.1; 690.2 msec ± 109.7; and 38.2 ± 4.4, respectively) (P < .05 for all comparisons). There were no differences between the pre- and postanemia groups in terms of LV ejection fraction (mean, 72.7% ± 2.1 vs 73.2% ± 4.7; P = .78) and ECV (mean, 15.5% ± 2.0 vs 16.0% ± 1.9; P = .24). Conclusion Myocardial ECV measured with contrast-enhanced T1 mapping cardiac MR imaging did not significantly change despite changes in hematocrit level in anemic rat models. Extrapolation of this finding from animal models to human subjects suggests that ECV measured with MR imaging could be a robust parameter in anemic patients., (© RSNA, 2018 Online supplemental material is available for this article.)

A reliable, non-invasive diagnostic method is needed for early detection and serial monitoring of cardiotoxicity, a well-known side effect of chemotherapy. This study aimed to assess the feasibility of T1-mapping cardiac magnetic resonance imaging (CMR) for evaluating subclinical myocardial changes in a doxorubicin-induced cardiotoxicity rabbit model. Adult male New Zealand White rabbits were injected twice-weekly with doxorubicin and subjected to CMR on a clinical 3T MR system before and every 2-4 weeks post-drug administration. Native T1 and extracellular volume (ECV) values were measured at six mid-left ventricle (LV) and specific LV lesions. Histological assessments evaluated myocardial injury and fibrosis. Three pre-model and 11 post-model animals were included. Myocardial injury was observed from 3 weeks. Mean LV myocardium ECV values increased significantly from week 3 before LV ejection fraction decreases (week 6), and ECVs of the RV upper/lower insertion sites and papillary muscle exceeded those of the LV. The mean native T1 value in the mid-LV increased significantly increased from week 6, and LV myocardium ECV correlated strongly with the degree of fibrosis (r = 0.979, p < 0.001). Myocardial T1 mapping, particularly ECV values, reliably and non-invasively detected early cardiotoxicity, allowing serial monitoring of chemotherapy-induced cardiotoxicity.

Cardiac magnetic resonance (CMR) imaging is widely used in various medical fields related to cardiovascular diseases. Rapid technological innovations in magnetic resonance imaging in recent times have resulted in the development of new techniques for CMR imaging. T1 and T2 image mapping sequences enable the direct quantification of T1, T2, and extracellular volume fraction (ECV) values of the myocardium, leading to the progressive integration of these sequences into routine CMR settings. Currently, T1, T2, and ECV values are being recognized as not only robust biomarkers for diagnosis of cardiomyopathies, but also predictive factors for treatment monitoring and prognosis. In this study, we have reviewed various T1 and T2 mapping sequence techniques and their clinical applications.

Objectives: This study sought to evaluate whether patterns of myocardial change in doxorubicin-induced dilated cardiomyopathy determined using dual-energy computed tomography (CT) were similar to characterization by extracellular volume fraction (ECV) using cardiac magnetic resonance (CMR) T1-mapping and collagen volume fraction (CVF) measured using histology., Background: Anthracycline chemoagents are effective against a wide range of malignant conditions. However, cardiotoxicity is a well-known adverse effect of these drugs. Dual-energy CT could be as useful as magnetic resonance (MR) to evaluate myocardial change in anthracycline-induced cardiotoxicity., Methods: A dilated cardiomyopathy rabbit model was generated by injecting 11 adult New Zealand rabbits with 1.0 mg/kg of doxorubicin twice weekly for 16 weeks. Contrast-enhanced dual-energy CT and pre-contrast and post-contrast T1-mapping CMR using a prototype modified Look-Locker inversion recovery on a clinical 3-T scanner were performed on 15 rabbits, including 4 control animals, to calculate ECV at baseline, and at 6, 12, and 16 weeks after doxorubicin administration., Results: The mean ECV values (%) on CT and CMR at 6, 12, and 16 weeks after modeling were significantly higher than those measured at baseline (CT ECV: 35.3%, 41.9%, 42.1% vs. 28.5%; MR ECV: 32.6%, 35.8%, 41.3% vs. 28.8%, respectively; all p < 0.001). CT ECV and MR ECV values were well correlated (r = 0.888; p < 0.001). Both were well correlated with CVF on histology (CT ECV vs. CVF, r = 0.925, p < 0.001 and MR ECV vs. CVF, r = 0.961, p < 0.001, respectively)., Conclusions: Dual-energy CT ECV correlated well with CMR and histology. Dual-energy CT is useful for characterizing doxorubicin-induced cardiomyopathy by measuring ECV fraction; however, further technical improvements are desirable to lower motion artifact and improve image quality of the iodine map., (Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Sclerosing pneumocytoma (SP) of the lung is a rare benign neoplasm. Here, we describe an unusual presentation of SP with a wax-and-wane pattern of growth in a 47-year-old woman. Tumor diameter decreased over a 3-year follow-up period and then increased on serial follow-up computed tomography scans. The mass showed high signal intensity on both T1- and T2-weighted chest magnetic resonance imaging (MRI) and early enhancement with a plateau on dynamic MRI. We speculate that intratumoral bleeding and resorption processes accounted for the changes in tumor size.

To establish extracellular volume fraction (ECV) thresholds corresponding to myocardial lesion detected by late-gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) imaging. Fifty-six patients with myocardial infarction or hypertrophic cardiomyopathy underwent LGE, pre- and post-contrast modified Look-Locker inversion recovery (MOLLI) sequences on a 3-T CMR system. Short-axis MOLLI images generated ECV maps of left ventricular (LV) walls. The LGE areas were semi-automatically determined by different signal threshold techniques. The areas of elevated ECV were measured using ECV thresholds of 28-48%. The LGE areas were compared with the areas of elevated ECV at the corresponding LV levels. The myocardial areas of LGE and elevated ECVs showed a strong and positive correlation (P < 0.01). The LGE threshold, set at two standard deviations above the mean signal from the remote myocardium, corresponded well with the area of ECV >32%. When using the full width at half-maximum (FWHM) technique, the LGE area corresponded well with the area of ECV >42 or 44%. By applying particular ECV thresholds, myocardial ECV maps can define myocardial status equivalent to LGE, and definite ECV thresholds may be useful for the straightforward evaluation of myocardial phenotypes.

Introduction: The aim of this paper was to evaluate the angioarchitectural factors that can induce concurrent cavernous malformation (CM) in the territory of developmental venous anomaly (DVA)., Methods: From January 2006 to December 2007, 21 patients with 23 CMs in the territory of DVA were retrospectively analyzed (M; F = 12; 9, mean age = 53.3). Gadovist®-enhanced three-dimensional spoiled gradient-echo images on a 3 T magnetic resonance (MR) scanner were used. We investigated the presence of angioarchitectural factors: factor 1, the angulated course of curved medullary or draining vein in the distal portion of CM; factor 2, narrowing of distal draining vein; factor 3, severe medullary venous tortuosity. These were also analyzed for control group of 23 subjects (M; F = 11; 12, mean age = 46)., Results: Factor 1 was demonstrated in 22 cases (97%) and the CM occurred in a position of 90° or less of an abrupt angulated medullary or draining vein in 15 cases (65%) of the study group. Factor 2 was found in 13 cases (57%) with the diameter reduction of 50% or more in five cases. The mean ratio of diameter reduction was 0.53. Factor 3 was found in 17 cases (74%). Analyzing the independent factors, the p values for factors 1 and 3 were <.05, i.e., statistically significant. If combination of more than two factors was present, the p values for all the combinations were <0.05, i.e., statistically significant., Conclusion: Anatomical angioarchitectural factors might be the key factors in causing concurrent sporadic CM within the territory of DVA by causing disturbance of blood flow.

Objective: To evaluate the use of measuring intrasyrinx fluid motion in syringomyelia by spatial modulation of magnetization (SPAMM)-magnetic resonance imaging (MRI) for predicting postoperative results., Materials and Methods: Fourteen patients with syringomyelia, who underwent surgery between 1995 and 2004 and took both preoperative SPAMM-MRI and postoperative MRI, were reviewed retrospectively. The SPAMM-MRI was obtained on a 1.5-T system using the electrocardiogram-triggered multiphase image technique with repetition time/time to echo/diffusion time/flip angle = 42 milliseconds/7.2 milliseconds/0 to 600 milliseconds/20 degrees. Three radiologists analyzed the tagging band shifting of the intrasyrinx fluid motions on the preoperative SPAMM-MRI. If the tagging band shifting during the systolic phase was more than half of the band space, it was regarded as good fluid motion. The correlation between the preoperative intrasyrinx fluid motion and the postoperative shrinkage of the syrinx was statistically analyzed., Results: The underlying causes of the syringomyelia were Arnold-Chiari malformation (7 patients), trauma (4 patients), and infectious disease (3 patients). Eight of 9 patients who had good fluid motion in the syrinx showed postoperative shrinkage of the syrinx. However, the 5 patients who had poor fluid motion showed no shrinkage of the syrinx. The fluid motion of the syrinx was highly correlated with the postoperative shrinkage of the syrinx (P < 0.01)., Conclusions: Evaluation of the intrasyrinx fluid motion in syringomyelia using the SPAMM-MRI can be a useful predictor of postoperative results and may indicate how well the pulse wave is transmitted from the heart to the syrinx.

Background: Myocardial fibrosis is an important prognostic factor in hypertrophic cardiomyopathy (HCM). However, the contribution from a wide spectrum of genetic mutations has not been well defined. We sought to investigate effect of sarcomere and mitochondria-related mutations on myocardial fibrosis in HCM. Methods: In 133 HCM patients, comprehensive genetic analysis was performed in 82 nuclear DNA (33 sarcomere-associated genes, 5 phenocopy genes, and 44 nuclear genes linked to mitochondrial cardiomyopathy) and 37 mitochondrial DNA. In all patients, cardiovascular magnetic resonance (CMR) was performed, including 16-segmental thickness, late gadolinium enhancement (LGE), native and post-T1, extracellular volume fraction (ECV), and T2, along with echo-Doppler evaluations. Results: Patients with sarcomere mutation (SM, n = 41) had higher LGE involved segment, % LGE mass, ECV and lower post-T1 compared to patients without SM (n = 92, all p < 0.05). When classified into, non-mutation (n = 67), only mitochondria-related mutation (MM, n = 24), only-SM (n = 36) and both SM and MM (n = 5) groups, only-SM group had higher ECV and LGE than the non-mutation group (all p < 0.05). In non-LGE-involved segments, ECV was significantly higher in patients with SM. Within non-SM group, patients with any sarcomere variants of uncertain significance had higher echocardiographic Doppler E/e' (p < 0.05) and tendency of higher LGE amount and ECV (p > 0.05). However, MM group did not have significantly higher ECV or LGE amount than non-mutation group. Conclusions: SMs are significantly related to increase in myocardial fibrosis. Although, some HCM patients had pathogenic MMs, it was not associated with an increase in myocardial fibrosis. [ABSTRACT FROM AUTHOR]