Avulsion Injuries of the Pelvis and Hip.

BACKGROUND: Avulsion injuries of the pelvis and hip region are typical injuries in adolescent athletes but can be found in adults as well. Typical sites for avulsion injuries include the origin/insertion of tendons and ligaments. Among adolescents, the not yet ossified apophysis is also frequently involved. The pelvis and hip are especially prone to such injuries due to their complex musculotendinous anatomy. Clinical history and physical examination in combination with the recognition of typical imaging findings are essential for correct diagnosis of these mostly acute, but sometimes also chronic injuries. METHODS: This review article describes typical avulsion injuries of the pelvis and hip and illustrates common radiological findings. Taking current literature into account, there is a special focus on the trauma mechanism, clinical examination, typical imaging findings and clinical management. RESULTS AND CONCLUSION: Detailed knowledge of musculotendinous anatomy and typical injury mechanisms allows a correct diagnosis of avulsion injuries often only based on clinical examination and radiographic findings. Further imaging with ultrasound and MRI may be necessary to evaluate tendon retraction in non-osseous avulsion injuries and extent of soft-tissue damage. Knowledge of potential complications of acute/chronic injuries can help to avoid unnecessary examinations or invasive interventions. Conservative management of avulsion injuries usually leads to functionally good results. However, in the case of competitive athletes, relatively wide bone fragment dislocation or marked tendon retraction, operative re-fixation may be considered in order to expedite the rehabilitation process. KEY POINTS: · Avulsion injuries are common injuries at the pelvic region especially in adolescent athletes, due to not yet ossified apophysis.. · Excellent anatomical knowledge is essential for proper diagnostic evaluation and predicting the mechanism of injury.. · Imaging plays a crucial role in diagnosing avulsion injuries starting from X-Ray and using MRI and CT for anatomical details by utilizing multiplanar capabilities.. CITATION FORMAT: · Albtoush OM, Bani-Issa J, Zitzelsberger T et al. Avulsion Injuries of the Pelvis and Hip. Fortschr Röntgenstr 2020; 192: 431 - 440.

Performance of two Methods for Cardiac MRI Edema Mapping: Dual-Contrast Fast Spin-Echo and T2 Prepared Balanced Steady State Free Precession.

PURPOSE: To compare true positive and false negative results of myocardial edema mapping in two methods. Myocardial edema may be difficult to detect on cardiac MRI. MATERIALS AND METHODS: 76 patients (age 59 ±â€Š11 years, 15 female) with acute myocardial infarction (MI) and 10 healthy volunteers were prospectively included in this single-center study. 1.5 T cardiac MRI was performed in patients 2.5 days after revascularization (median) for edema mapping: Steady State Free Precession (SSFP) mapping sequence with T2-preparation pulses (T2prep); and dual-contrast Fast Spin-Echo (dcFSE) signal decay edema mapping. Late gadolinium enhancement (LGE) was used as the reference for expected edema in acute MI. RESULTS: 311 myocardial segments in patients were acutely infarcted with mean T2 73 ms for T2prep SSFP vs. 87 ms for dcFSE edema mapping. In healthy volunteers the mean T2 was 56 ms for T2prep SSFP vs. 50 ms for dcFSE edema mapping. Receiver operating characteristic (ROC) curve for T2prep SSFP show area under the curve (AUC) 0.962, p < 0.0001, Youden index J 0.8266, associated criterion > 60 ms, sensitivity 94 %, specificity 89 %. dcFSE ROC AUC 0.979, p < 0.0001, J 0.9219, associated criterion > 64 ms, sensitivity 93 %, specificity 99 %. CONCLUSION: Both edema mapping methods indicate high-grade edema with high sensitivity. Nevertheless, edema in acute infarction may be focally underestimated in both mapping methods. KEY POINTS: · Sensitivity for edema detection is high for both methods.. · Edema may be focally underestimated by T2prep SSFP edema mapping and dcFSE mapping.. CITATION FORMAT: · Krumm P, Martirosian P, Rath D et al. Performance of two Methods for Cardiac MRI Edema Mapping: Dual-Contrast Fast Spin-Echo and T2 Prepared Balanced Steady State Free Precession. Fortschr Röntgenstr 2020; 192: 669 - 677.

Magnetic Resonance-based Assessment of Myocardial 2-Dimensional Strain Using Feature Tracking: Association With Cardiovascular Risk Factors in a Population-based Cohort Free of Cardiovascular Disease.

PURPOSE: Myocardial strain analysis is a promising tool for the detection of subtle but relevant alterations of left ventricular function, also in asymptomatic subjects. Thus, we determined the feasibility of cardiac magnetic resonance-based 2D global strain analysis using feature tracking and its association with cardiovascular risk factors in a sample from the general population. MATERIALS AND METHODS: Subjects without a history of cardiocerebrovascular disease were enrolled in a substudy of the population-based KORA (Cooperative Health Research in the Region of Augsburg) cohort. In all participants with the absence of late gadolinium enhancement, longitudinal and circumferential global strains were measured on Cine SSFP imaging (TR: 29.97 ms, TE: 1.46 ms, ST: 8 mm), using a semiautomatic segmentation algorithm (CVI42, Circle, Canada). Differences in strain values according to age, sex, body mass index, hypertension, diabetes mellitus, and hyperlipidemia were derived using linear regression analysis. RESULTS: Among 360 subjects (mean age, 56.2±9.2 y, 57% male), the average global systolic radial strain was 40.1±8.2%, circumferential 19.9±2.7%, and longitudinal 19.8±3.2%. Male sex was associated with decreased global strain values, independent of the strain direction (all P<0.001). Although many cardiovascular risk factors were correlated with strain in univariate analysis, mainly waist-to-hip ratio and HbA1c remained associated with decreased radial and circumferential strains in fully adjusted models. Similarly, higher radial and circumferential strains were observed in older subjects (ß=0.14, P=0.01 and ß=0.11, P=0.04, respectively). CONCLUSIONS: Strain analysis using magnetic resonance feature tracking is feasible in population-based cohort studies and shows differences with respect to age and sex as well as an independent association with markers of metabolic syndrome.

Young patient with hantavirus-induced myocarditis detected by comprehensive cardiac magnetic resonance assessment.

BACKGROUND: We report a case of hantavirus-induced myocarditis in a young adult. Hantavirus showed a rapid increase of infections in the year 2017. Only scarce data is available about potential myocardial involvement in hantavirus infections. With ECG and echocardiography providing often inconclusive results, a multiparametric cardiac magnetic resonance protocol with distinct myocardial tissue characterization seems to be the adequate tool for detecting even slight myocardial alterations. CASE PRESENTATION: This case started with the presentation of young adult suffering from headache and abdominal pain. Thrombocytes were decreased, creatinine was elevated, and there was massive proteinuria. Puumala virus IgG ELISA turned out to be positive, and specific antibodies (IgG and IgM) could be detected in the serum, and confirmed by immunoassay. The patient was admitted to the nephrology department for supportive therapy. Few days later, the patient reported chest pain and dyspnea. High sensitivity troponin I rose up to 0.32 µg/l (normal range below 0.04 µg/l) with an increase of the creatinkinase to 319 U/l (normal max. 190 U/l), no dynamic ECG changes could be observed. Echocardiography revealed a normal left ventricular function without regional wall motion abnormalities, no pericardial effusion or valve abnormalities, coronary artery disease could be excluded by computed tomography. A multiparametric cardiac magnetic resonance protocol including recent mapping techniques confirmed myocardial involvement induced by acute hantavirus infection. In the next few weeks, the patient's state of health rapidly improved and symptoms of chest pain and dyspnea disappeared. Follow up multiparametric CMR exam showed substantial decrease of the previously observed myocardial alterations during acute hantavirus infection suggesting myocardial healing. CONCLUSIONS: This case demonstrates that a CMR protocol including recent mapping techniques and established late gadolinium enhancement technique is an adequate non-invasive tool for both 1) initial detection, and 2) follow up of patients with hantavirus-induced myocarditis, which might be more common than previously known.

Image quality of arterial phase and parenchymal blood volume (PBV) maps derived from C-arm computed tomography in the evaluation of transarterial chemoembolization.

BACKGROUND: To evaluate the benefits of arterial phase imaging and parenchymal blood volume (PBV) maps acquired by C-arm computed tomography during TACE procedure in comparison to cross-sectional imaging (CSI) using CT or MRI. METHODS: From January 2014 to December 2016, a total of 29 patients with HCC stage A or B (mean age 65 years; range 47 to 81 years, 86% male) were included in this study. These patients were referred to our department for TACE treatment and received peri-interventional C-arm CT. Dual phase findings of each lesion in terms of overall image quality, conspicuity, tumor size and feeding arteries were compared between arterial phase imaging and PBV using 5-point semi-quantitative Likert-scale, whereby pre-interventional CSI served as reference standard. RESULTS: A significantly higher overall image quality of the PBV maps compared to arterial phase C-arm CT acquisitions (4.34 (±0.55) vs. 3.93 (±0.59), p = 0.0032) as well as a higher conspicuity of HCC lesions (4.27 ± 0.74 vs. 3.83 ± 1.08, p < 0.0001) was observed. Arterial phase imaging led to an overestimation of tumor size (mean size, 26.5 ± 15.9 mm) compared to PBV (24.9 ± 15.2 mm, p = 0.0004) as well as CSI (25.2 ± 15.1 mm), p = 0.021). Regarding detectability of tumor feeding arterial vessels, significantly more feeding vessels were detected in arterial phase C-arm CT (n = 1.67 ± 0.92 vessels) compared to PBV maps (n = 1.27 ± 0.63 vessels) (p = 0.0001). One lesion was missed in pre-interventional CT imaging, but detected by C-arm CT. CONCLUSION: The combination of PBV maps and arterial phase images acquired by C-arm CT during TACE procedure enables precise detection of the majority of HCC lesions and tumor feeding arteries and has therefore the potential to improve patient outcome.

Mid-term development of the right ventricle in competitive athletes.

BACKGROUND: Long-term intensive training induces physiological, morphological, and functional adaption of the athlete's heart. PURPOSE: To evaluate the development of athlete's heart during a mid-term follow-up of competitive athletes using cardiac magnetic resonance (CMR). MATERIAL AND METHODS: Eighteen competitive long-distance runners and triathletes (age 43 ± 13 years, 3 women) were prospectively examined in a longitudinal follow-up study 5.05 ± 0.6 years after baseline. CMR at 1.5-T was performed for functional and late gadolinium enhancement (LGE) imaging. Left ventricular (LV) and right ventricular (RV) end-diastolic volume (LVEDV, RVEDV) as well as ejection fraction (LVEF, RVEF), LV myocardial mass (LVMM), and atrial sizes were determined and compared to baseline in matched pairs statistics for paired difference. RESULTS: LVEDV (197 ± 38 mL vs. 196 ± 38 mL, paired difference -0.9 mL, P = 0.7) and LVEF (62 ± 7% vs. 62 ± 5%, paired difference 0.1%, P = 0.9) did not change during the follow-up period, whereas LVMM increased significantly (149 ± 31 g vs.164 ± 32 g, paired difference 14 g, P < 0.0001). RVEDV significantly increased from 221 ± 47 mL at baseline to 230 ± 52 mL (paired difference 10 mL, P = 0.0033). RVEF decreased from baseline 57 ± 8% to 53 ± 7% (paired difference -3%, P = 0.0234). Left atrial size showed no significant changes (24 ± 5 cm2 vs. 25 ± 6 cm2, paired difference 0.5 cm2, P = 0.17) and right atrial size increased significantly (30 ± 5 cm2 vs. 32 ± 4 cm2, paired difference 2 cm2, P = 0.0054). CONCLUSION: This study supports the theory of ongoing remodeling in an athlete's heart. Predominantly the right heart can further enlarge in a mid-term period. This response seems not linearly dependent on a steady, decreased, or increased training volume.

Myocardial tissue characterization by contrast-enhanced cardiac magnetic resonance imaging in subjects with prediabetes, diabetes, and normal controls with preserved ejection fraction from the general population.

Aims: To characterize changes in the myocardium in subjects with prediabetes, diabetes, and healthy controls with preserved left ventricular ejection fraction (LVEF) by using cardiac magnetic resonance imaging (CMR) in a sample from the general population. Methods and results: Subjects without history of cardiovascular disease and preserved LVEF but established diabetes, prediabetes, and controls from a population-based cohort underwent contrast-enhanced CMR. Obtained parameters included left ventricular (LV) function and morphology, late gadolinium enhancement as well as T1-mapping and derivation of extracellular volume fraction (ECV) by modified Look-Locker inversion recovery for diffuse fibrosis in a subset of patients. Fibrosis volume and cell volume were calculated and LV remodelling index was calculated by dividing the LV mass by its end-diastolic volume. Among 343 subjects (56.1 ± 9.2 years, 57% males), 47 subjects were classified as diabetes, 78 as prediabetes, and 218 as controls. Haematocrit values and thus ECV parameters were available in 251 subjects. LV remodelling index was significantly higher in participants with prediabetes and diabetes, independent of body mass index (BMI), hypertension, age, and sex. ECV was decreased in subjects with prediabetes and diabetes compared with healthy controls (23.1 ± 2.4% and 22.8 ± 3.0%, both P < 0.007). In contrast, cell volume was significantly higher in subjects with prediabetes and diabetes as compared with controls (109.1 ± 23.8 and 114.9 ± 32.3 mL vs. 96.5 ± 26.9 mL, both P < 0.03, respectively). However, differences in ECV and cell volume attenuated after the adjustment for cardiometabolic risk factors, including age, sex, BMI, and hypertension. Conclusion: Subjects with prediabetes and diabetes but preserved LVEF had higher LV remodelling indices, suggesting early detectable changes in the disease process, while diffuse myocardial fibrosis appears to be less relevant at this stage.

Single-Breath-Hold Evaluation of Cardiac Function with Use of Time-Resolved Parallel Cardiac Magnetic Resonance.

Using cardiac magnetic resonance, we tested whether a single-breath-hold approach to cardiac functional evaluation was equivalent to the established multiple-breath-hold method. We examined 39 healthy volunteers (mean age, 31.9 ± 11.4 yr; 22 men) by using 1.5 T with multiple breath-holds and our proposed single breath-hold. Left ventricular and right ventricular ejection fractions (LVEF and RVEF), LV and RV end-diastolic volumes (LVEDV and RVEDV), and LV myocardial mass (LVMM) were compared by using Bland-Altman plots; LVEF and RVEF were tested for equivalence by inclusion of 95% confidence intervals (CIs). Equivalence of the methods was assumed within the range of -5% to 5%. In the multiple- versus the single-breath-hold method, LVEF was 0.62 ± 0.05 versus 0.62 ± 0.04, and RVEF was 0.59 ± 0.06 versus 0.59 ± 0.07. The mean difference in both methods was -0.2% (95% CI, -1 to 0.6) for LVEF and 0.3% (95% CI, -0.8 to 1.5) for RVEF. The mean differences between methods fit within the predetermined range of equivalence, including the 95% CI. The mean relative differences between the methods were 3.8% for LVEDV, 4.5% for RVEDV, and 1.6% for LVMM. Results of our single-breath-hold method to evaluate LVEF and RVEF were equivalent to those of the multiple-breath-hold technique. In addition, LVEDV, RVEDV, and LVMM showed low bias between methods.

Imaging characteristics of cardiac metastases in patients with malignant melanoma.

BACKGROUND: Due to prolonged survival and technical advances in CT imaging, cardiac metastases in patients with malignant melanoma are observed more frequently nowadays. The aim of the present study was to assess the anatomic distribution as well as the morphologic and histologic appearance of cardiac metastases from malignant melanoma. METHODS: Twenty five patients with known metastasized melanoma and with incidental finding of cardiac metastases during routine staging CT were retrospectively included in this study. CT images were assessed for the presence, localization and extent of cardiac metastases. Histological results, mutational analysis and tumor markers were reviewed. RESULTS: Fourteen out of 25 patients presented with singular cardiac mass (56%), whereas ten patients (40%) presented with multifocal and one patient with disseminated cardiac metastases. Twelve patients presented with endocardial (48%), eight with myocardial and two with pericardial metastases. Most frequent site involved in endocardial metastases was the right atrium (67%) followed by the right ventricle (33%). There seems to be a correlation between histological subtype and location of cardiac metastasis. Median survival after diagnosis of cardiac metastases was 8 months, with no significant difference regarding the localization of metastases within the heart. CONCLUSION: Cardiac metastases can involve every part of the heart possibly in dependence of histological subtype. The awareness of different types of cardiac metastases and their characteristic appearance on CT images is necessary for further investigations and might contribute to targeted therapy.

Cardiac MRI left ventricular global function index and quantitative late gadolinium enhancement in unrecognized myocardial infarction.

PURPOSE: To compare left ventricular global function index (LVGFI) and quantitative late gadolinium enhancement (LGE) in patients with unrecognized myocardial infarction (UMI), recognized myocardial infarction (RMI) and without myocardial infarction (MI). MATERIAL AND METHODS: Under waiver of the Institutional Review Board 235 patients (age 63.5±10.5years, 57 female) were retrospectively evaluated. All patients had undergone cardiac MRI at 1.5T for symptoms of CAD. 67 patients (29%) had suffered a known RMI before. Functional imaging and full-intensity late gadolinium enhancement (LGE) imaging were evaluated for LVGFI and quantitative LGE mass. RESULTS: Of 168 patients without history of RMI, 48 patients (29%) had UMI, 120 patients had no MI. LVGFI was lower in RMI patients (34±8% [range 16;52]), and UMI patients (35±8% [range 10;51]), compared to patients with no MI (38±7% [range 16;55]) respectively and similar between RMI and UMI patients. RMI patients had full-intensity LGE in 11±6% of left ventricular myocardial mass (LVMM). UMI patients had LGE in 9±5% of LVMM. RMI patients had significantly more LGE than UMI patients (p=0.0096). CONCLUSION: LGE quantification is effective to assess infarction scar size in RMI and UMI patients. LVGFI provides information on cardiac function and morphology but does not allow for a reliable differentiation between patients with and without history of MI, due small differences and wide overlap of LVGFI values for all three patient groups. This may be a reason why LVGFI is not applied in clinical routine.

Subclinical Disease Burden as Assessed by Whole-Body MRI in Subjects With Prediabetes, Subjects With Diabetes, and Normal Control Subjects From the General Population: The KORA-MRI Study.

Detailed pathophysiological manifestations of early disease in the context of prediabetes are poorly understood. This study aimed to evaluate the extent of early signs of metabolic and cardio-cerebrovascular complications affecting multiple organs in individuals with prediabetes. Subjects without a history of stroke, coronary artery disease, or peripheral artery disease were enrolled in a case-control study nested within the Cooperative Health Research in the Region of Augsburg (KORA) FF4 cohort and underwent comprehensive MRI assessment to characterize cerebral parameters (white matter lesions, microbleeds), cardiovascular parameters (carotid plaque, left ventricular function, and myocardial late gadolinium enhancement [LGE]), and metabolic parameters (hepatic proton-density fat fraction [PDFF] and subcutaneous and visceral abdominal fat). Among 400 subjects who underwent MRI, 103 subjects had prediabetes and 54 had established diabetes. Subjects with prediabetes had an increased risk for carotid plaque and adverse functional cardiac parameters, including reduced early diastolic filling rates as well as a higher prevalence of LGE compared with healthy control subjects. In addition, people with prediabetes had significantly elevated levels of PDFF and total and visceral fat. Thus, subjects with prediabetes show early signs of subclinical disease that include vascular, cardiac, and metabolic changes, as measured by whole-body MRI after adjusting for cardiometabolic risk factors.

Cardiovascular magnetic resonance patterns of biopsy proven cardiac involvement in systemic sclerosis.

BACKGROUND: To determine morphological and functional cardiovascular magnetic resonance (CMR) patterns in histopathologically confirmed myocardial involvement in patients with systemic sclerosis (SSc). METHODS: Twenty patients (6 females; mean age 41 ± 11 years) with histopathologically proven cardiac involvement in SSc in the years 2008-2016 were retrospectively evaluated. Morphological, functional and late gadolinium enhancement (LGE) images were acquired in standard angulations at 1.5 T CMR. Pathologies were categorized: 1) Pericardial effusion; 2) pathologic left (LV) or right ventricular (RV) contractility (hypokinesia, dyssynchrony, and diastolic restriction); 3) reduced left (LV-EF) and right ventricular ejection fraction (RV-EF); 4) fibrosis and/or inflammation (positive LGE); 5) RV dilatation. 95 % confidence intervals (CI) were calculated for appearance of pathologic EF and RV dilatation. RESULTS: Seven patients (35 %) had positive CMR findings in three categories, 9 patients (45 %) in four categories and 4 patients (20 %) in five categories. The distribution of pathologic findings was: minimal pericardial effusion in 7 patients (35 %), moderate pericardial effusion >5 mm in nine patients (45 %); abnormal LV or RV contractility in 19 patients (95 %), reduced LV or RV function in 14 patients (70 %; 95 % CI: 51-88 %), pathologic LGE in all patients, RV dilatation in 6 patients (30 %; 95 % CI: 15-54 %). CONCLUSIONS: CMR diagnosis of myocardial involvement in SSc requires increased attention to subtle findings. Pathologic findings in at least three of five categories indicate myocardial involvement in SSc.

Signal decay mapping of myocardial edema using dual-contrast fast spin-echo MRI.

PURPOSE: To introduce a dual-contrast fast spin-echo (dcFSE) sequence for signal decay mapping of myocardial edema. MATERIALS AND METHODS: After consultation with the Institutional Review Board, 22 acute myocardial infarction (MI) patients were examined with magnetic resonance imaging (MRI) at 1.5T 2 days after revascularization. Edema was evaluated in 16 myocardial segments with an exponential fit for signal decay time (SDT) in dcFSE mapping and T2 signal intensity ratio for single-contrast FSE. Myocardial viability was evaluated in late gadolinium enhancement (LGE). A control group of 10 volunteers was examined for edema imaging. SDT was compared in segment groups: 1) with LGE in MI, 2) penumbra, 3) remote from LGE, 4) controls. Groups 1/3 and 3/4 were tested on difference. Three phantoms providing similar T2 but different T1 relaxation times (low, intermediate, high) were examined with dcFSE and multicontrast spin echo sequence as a reference. RESULTS: The SDT/T2 ratio for segment groups was 1) 82msec/1.7 in segments with LGE; 2) 65msec/1.6 for penumbra, 3) 62msec/1.7 for remote segments, and 4) 50msec/1.6 in controls. In dcFSE group 1/3 (P < 0.0001) and in group 3/4 (P = 0.0002) SDT was significantly different. In single-contrast FSE the T2 ratio was not significantly different for both tests: 1/3 P = 0.1889; 3/4 P = 0.8879. T2 -overestimation of dcFSE was 23% in low, 29% in intermediate, and 35% in highly T1 contaminated phantoms. CONCLUSION: dcFSE signal decay edema mapping is feasible in volunteers and patients. DcFSE SDT is superior to T2 ratio for detection of high-grade and diffuse myocardial edema. J. Magn. Reson. Imaging 2016;44:186-193.

Potential of Diffusion Tensor Imaging and Relaxometry for the Detection of Specific Pathological Alterations in Parkinson's Disease (PD).

The purpose of the present study was to evaluate the potential of multimodal MR imaging including mean diffusivity (MD), fractional anisotropy (FA), relaxation rates R2 and R2* to detect disease specific alterations in Parkinson's Disease (PD). We enrolled 82 PD patients (PD-all) with varying disease durations (≤5 years: PD≤5, n = 43; >5 years: PD>5, n = 39) and 38 matched healthy controls (HC), receiving diffusion tensor imaging as well as R2 and R2* relaxometry calculated from multi-echo T2*-weighted and dual-echo TSE imaging, respectively. ROIs were drawn to delineate caudate nucleus (CN), putamen (PU), globus pallidus (GP) and substantia nigra (SN) on the co-registered maps. The SN was divided in 3 descending levels (SL 1-3). The most significant parameters were used for a flexible discrimination analysis (FDA) in a training collective consisting of 25 randomized subjects from each group in order to predict the classification of remaining subjects. PD-all showed significant increases in MD, R2 and R2* within SN and its subregions as well as in MD and R2* within different basal ganglia regions. Compared to the HC group, the PD≤5 and the PD>5 group showed significant MD increases within the SN and its lower two subregions, while the PD≤5 group exhibited significant increases in R2 and R2* within SN and its subregions, and tended to elevation within the basal ganglia. The PD>5 group had significantly increased MD in PU and GP, whereas the PD≤5 group presented normal MD within the basal ganglia. FDA achieved right classification in 84% of study participants. Micro-structural damage affects primarily the SN of PD patients and in later disease stages the basal ganglia. Iron contents of PU, GP and SN are increased at early disease stages of PD.