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1.
Eur Respir J ; 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38936968

ABSTRACT

INTRODUCTION: Chronic thromboembolic pulmonary hypertension (CTEPH) is often diagnosed late in acute pulmonary embolism (PE) survivors: more efficient testing to expedite diagnosis may considerably improve patient outcomes. The InShape II algorithm safely rules out CTEPH (failure rate 0.29%) while requiring echocardiography in only 19% of patients but may be improved by adding detailed reading of the computed tomography pulmonary angiography (CTPA) diagnosing the index PE. METHODS: Twelve new algorithms, incorporating the CTEPH prediction score, ECG reading, NT-proBNP levels and dedicated CTPA reading were evaluated in the international InShape II (n=341) and part of the German FOCUS cohort (n=171). Evaluation criteria included failure rate, defined as the incidence of confirmed CTEPH in PE patients in whom echocardiography was deemed unnecessary by the algorithm, and the overall net reclassification index (NRI) compared to the InShape II algorithm. RESULTS: The algorithm starting with CTPA reading of the index PE for 6 signs of CTEPH, followed by the ECG/NTproBNP assessment and echocardiography resulted in the most beneficial change compared to InShape II with a need for echocardiography in 20% (+5%), a failure rate of 0%, and an NRI of +3.5, reflecting improved performance over the InShape II algorithm. In the FOCUS cohort, this approach lowered echocardiography need to 24% (-6%) and missed no CTEPH cases, with an NRI of +6.0. CONCLUSION: Dedicated CTPA reading of the index PE improved the performance of the InShape II algorithm and may improve the selection of PE survivors who require echocardiography to rule out CTEPH.

2.
AJR Am J Roentgenol ; 222(3): e2330481, 2024 03.
Article in English | MEDLINE | ID: mdl-38197760

ABSTRACT

BACKGROUND. Calcium blooming causes stenosis overestimation on coronary CTA. OBJECTIVE. The purpose of this article was to evaluate the impact of virtual monoenergetic imaging (VMI) reconstruction level on coronary artery stenosis quantification using photon-counting detector (PCD) CT. METHODS. A phantom containing two custom-made vessels (representing 25% and 50% stenosis) underwent PCD CT acquisitions without and with simulated cardiac motion. A retrospective analysis was performed of 33 patients (seven women, 26 men; mean age, 71.3 ± 9.0 [SD] years; 64 coronary artery stenoses) who underwent coronary CTA by PCD CT followed by invasive coronary angiography (ICA). Scans were reconstructed at nine VMI energy levels (40-140 keV). Percentage diameter stenosis (PDS) was measured, and bias was determined from the ground-truth stenosis percentage in the phantom and ICA-derived quantitative coronary angiography measurements in patients. Extent of blooming artifact was measured in the phantom and in calcified and mixed plaques in patients. RESULTS. In the phantom, PDS decreased for 25% stenosis from 59.9% (40 keV) to 13.4% (140 keV) and for 50% stenosis from 81.6% (40 keV) to 42.3% (140 keV). PDS showed lowest bias for 25% stenosis at 90 keV (bias, 1.4%) and for 50% stenosis at 100 keV (bias, -0.4%). Blooming artifacts decreased for 25% stenosis from 61.5% (40 keV) to 35.4% (140 keV) and for 50% stenosis from 82.7% (40 keV) to 52.1% (140 keV). In patients, PDS for calcified plaque decreased from 70.8% (40 keV) to 57.3% (140 keV), for mixed plaque decreased from 69.8% (40 keV) to 56.3% (140 keV), and for noncalcified plaque was 46.6% at 40 keV and 54.6% at 140 keV. PDS showed lowest bias for calcified plaque at 100 keV (bias, 17.2%), for mixed plaque at 140 keV (bias, 5.0%), and for noncalcified plaque at 40 keV (bias, -0.5%). Blooming artifacts decreased for calcified plaque from 78.4% (40 keV) to 48.6% (140 keV) and for mixed plaque from 73.1% (40 keV) to 44.7% (140 keV). CONCLUSION. For calcified and mixed plaque, stenosis severity measurements and blooming artifacts decreased at increasing VMI reconstruction levels. CLINICAL IMPACT. PCD CT with VMI reconstruction helps overcome current limitations in stenosis quantification on coronary CTA.


Subject(s)
Coronary Stenosis , Plaque, Atherosclerotic , Male , Humans , Female , Middle Aged , Aged , Aged, 80 and over , Computed Tomography Angiography/methods , Retrospective Studies , Constriction, Pathologic , Tomography, X-Ray Computed/methods , Coronary Stenosis/diagnostic imaging
3.
J Magn Reson Imaging ; 58(2): 496-507, 2023 08.
Article in English | MEDLINE | ID: mdl-36264176

ABSTRACT

BACKGROUND: Four-dimensional (4D) flow MRI allows for the quantification of complex flow patterns; however, its clinical use is limited by its inherently long acquisition time. Compressed sensing (CS) is an acceleration technique that provides substantial reduction in acquisition time. PURPOSE: To compare intracardiac flow measurements between conventional and CS-based highly accelerated 4D flow acquisitions. STUDY TYPE: Prospective. SUBJECTS: Fifty healthy volunteers (28.0 ± 7.1 years, 24 males). FIELD STRENGTH/SEQUENCE: Whole heart time-resolved 3D gradient echo with three-directional velocity encoding (4D flow) with conventional parallel imaging (factor 3) as well as CS (factor 7.7) acceleration at 3 T. ASSESSMENT: 4D flow MRI data were postprocessed by applying a valve tracking algorithm. Acquisition times, flow volumes (mL/cycle) and diastolic function parameters (ratio of early to late diastolic left ventricular peak velocities [E/A] and ratio of early mitral inflow velocity to mitral annular early diastolic velocity [E/e']) were quantified by two readers. STATISTICAL TESTS: Paired-samples t-test and Wilcoxon rank sum test to compare measurements. Pearson correlation coefficient (r), Bland-Altman-analysis (BA) and intraclass correlation coefficient (ICC) to evaluate agreement between techniques and readers. A P value < 0.05 was considered statistically significant. RESULTS: A significant improvement in acquisition time was observed using CS vs. conventional accelerated acquisition (6.7 ± 1.3 vs. 12.0 ± 1.3 min). Net forward flow measurements for all valves showed good correlation (r > 0.81) and agreement (ICCs > 0.89) between conventional and CS acceleration, with 3.3%-8.3% underestimation by the CS technique. Evaluation of diastolic function showed 3.2%-17.6% error: E/A 2.2 [1.9-2.4] (conventional) vs. 2.3 [2.0-2.6] (CS), BA bias 0.08 [-0.81-0.96], ICC 0.82; and E/e' 4.6 [3.9-5.4] (conventional) vs. 3.8 [3.4-4.3] (CS), BA bias -0.90 [-2.31-0.50], ICC 0.89. DATA CONCLUSION: Analysis of intracardiac flow patterns and evaluation of diastolic function using a highly accelerated 4D flow sequence prototype is feasible, but it shows underestimation of flow measurements by approximately 10%. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 1.


Subject(s)
Imaging, Three-Dimensional , Magnetic Resonance Imaging , Male , Humans , Prospective Studies , Blood Flow Velocity , Imaging, Three-Dimensional/methods , Mitral Valve/diagnostic imaging , Reproducibility of Results
4.
J Magn Reson Imaging ; 2023 Sep 21.
Article in English | MEDLINE | ID: mdl-37732541

ABSTRACT

BACKGROUND: Detection of pulmonary perfusion defects is the recommended approach for diagnosing chronic thromboembolic pulmonary hypertension (CTEPH). This is currently achieved in a clinical setting using scintigraphy. Phase-resolved functional lung (PREFUL) magnetic resonance imaging (MRI) is an alternative technique for evaluating regional ventilation and perfusion without the use of ionizing radiation or contrast media. PURPOSE: To assess the feasibility and image quality of PREFUL-MRI in a multicenter setting in suspected CTEPH. STUDY TYPE: This is a prospective cohort sub-study. POPULATION: Forty-five patients (64 ± 16 years old) with suspected CTEPH from nine study centers. FIELD STRENGTH/SEQUENCE: 1.5 T and 3 T/2D spoiled gradient echo/bSSFP/T2 HASTE/3D MR angiography (TWIST). ASSESSMENT: Lung signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were compared between study centers with different MRI machines. The contrast between normally and poorly perfused lung areas was examined on PREFUL images. The perfusion defect percentage calculated using PREFUL-MRI (QDPPREFUL ) was compared to QDP from the established dynamic contrast-enhanced MRI technique (QDPDCE ). Furthermore, QDPPREFUL was compared between a patient subgroup with confirmed CTEPH or chronic thromboembolic disease (CTED) to other clinical subgroups. STATISTICAL TESTS: t-Test, one-way analysis of variance (ANOVA), Pearson's correlation. Significance level was 5%. RESULTS: Significant differences in lung SNR and CNR were present between study centers. However, PREFUL perfusion images showed a significant contrast between normally and poorly perfused lung areas (mean delta of normalized perfusion -4.2% SD 3.3) with no differences between study sites (ANOVA: P = 0.065). QDPPREFUL was significantly correlated with QDPDCE (r = 0.66), and was significantly higher in 18 patients with confirmed CTEPH or CTED (57.9 ± 12.2%) compared to subgroups with other causes of PH or with excluded PH (in total 27 patients with mean ± SD QDPPREFUL = 33.9 ± 17.2%). DATA CONCLUSION: PREFUL-MRI could be considered as a non-invasive method for imaging regional lung perfusion in multicenter studies. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 1.

5.
Eur Radiol ; 33(3): 2039-2051, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36322192

ABSTRACT

OBJECTIVES: Cardiac involvement in Anderson-Fabry disease (AFD) results in myocardial lipid depositions. An early diagnosis can maximize therapeutic benefit. Thus, this study aims to investigate the potential of cardiac MRI (CMR) based parameters of left atrial (LA) function and strain to detect early stages of AFD. METHODS: Patients (n = 58, age 40 (29-51) years, 31 female) with genetically proven AFD had undergone CMR including left ventricular (LV) volumetry, mass index (LVMi), T1, and late gadolinium enhancement, complemented by LA and LV strain measurements and atrial emptying fractions. Patients were stratified into three disease phases and compared to age and sex-matched healthy controls (HC, n = 58, age 41 [26-56] years, 31 female). RESULTS: A total of 19 early-, 20 intermediate-, and 19 advanced-phase patients were included. LV and LA reservoir strain was significantly impaired in all AFD phases, including early disease (both p < 0.001). In contrast, LA volumetry, T1, and LVMi showed no significant differences between the early phase and HC (p > 0.05). In the intermediate phase, LVMi and T1 demonstrated significant differences. In advanced phase, all parameters except active emptying fractions differed significantly from HC. ROC curve analyses of early disease phases revealed superior diagnostic confidence for the LA reservoir strain (AUC 0.88, sensitivity 89%, specificity 75%) over the LV strain (AUC 0.82). CONCLUSIONS: LA reservoir strain showed impairment in early AFD and significantly correlated with disease severity. The novel approach performed better in identifying early disease than the established approach using LVMi and T1. Further studies are needed to evaluate whether these results justify earlier initiation of therapy and help minimize cardiac complications. KEY POINTS: • Parameters of left atrial function and deformation showed impairments in the early stages of Anderson-Fabry disease and correlated significantly with the severity of Anderson-Fabry disease. • Left atrial reservoir strain performed superior to ventricular strain in detecting early myocardial involvement in Anderson-Fabry disease and improved diagnostic accuracies of approaches already using ventricular strain. • Further studies are needed to evaluate whether earlier initiation of enzyme replacement therapy based on these results can help minimize cardiac complications from Anderson-Fabry disease.


Subject(s)
Atrial Fibrillation , Fabry Disease , Heart Diseases , Humans , Female , Adult , Fabry Disease/diagnostic imaging , Fabry Disease/complications , Contrast Media , Gadolinium , Heart Atria/diagnostic imaging , Heart Diseases/complications
6.
Eur Radiol ; 33(8): 5489-5497, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36905466

ABSTRACT

Cardiac computed tomography (CT) and cardiac magnetic resonance imaging (MRI) are routine radiological examinations for diagnosis and prognosis of cardiac disease. The expected growth in cardiac radiology in the coming years will exceed the current scanner capacity and trained workforce. The European Society of Cardiovascular Radiology (ESCR) focuses on supporting and strengthening the role of cardiac cross-sectional imaging in Europe from a multi-modality perspective. Together with the European Society of Radiology (ESR), the ESCR has taken the initiative to describe the current status of, a vision for, and the required activities in cardiac radiology to sustain, increase and optimize the quality and availability of cardiac imaging and experienced radiologists across Europe. KEY POINTS: • Providing adequate availability for performing and interpreting cardiac CT and MRI is essential, especially with expanding indications. • The radiologist has a central role in non-invasive cardiac imaging examinations which encompasses the entire process from selecting the best modality to answer the referring physician's clinical question to long-term image storage. • Optimal radiological education and training, knowledge of the imaging process, regular updating of diagnostic standards, and close collaboration with colleagues from other specialties are essential.


Subject(s)
Heart Diseases , Radiology , Humans , Radiology/education , Heart , Radiography , Magnetic Resonance Imaging , Europe
7.
Eur Radiol ; 33(2): 1088-1101, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36194266

ABSTRACT

The European Society of Cardiovascular Radiology (ESCR) is the European specialist society of cardiac and vascular imaging. This society's highest priority is the continuous improvement, development, and standardization of education, training, and best medical practice, based on experience and evidence. The present intra-society consensus is based on the existing scientific evidence and on the individual experience of the members of the ESCR writing group on carotid diseases, the members of the ESCR guidelines committee, and the members of the executive committee of the ESCR. The recommendations published herein reflect the evidence-based society opinion of ESCR. The purpose of this second document is to discuss suggestions for standardized reporting based on the accompanying consensus document part I. KEY POINTS: • CT and MR imaging-based evaluation of carotid artery disease provides essential information for risk stratification and prediction of stroke. • The information in the report must cover vessel morphology, description of stenosis, and plaque imaging features. • A structured approach to reporting ensures that all essential information is delivered in a standardized and consistent way to the referring clinician.


Subject(s)
Carotid Artery Diseases , Radiology , Humans , Consensus , Magnetic Resonance Imaging/methods , Carotid Artery Diseases/diagnostic imaging , Tomography, X-Ray Computed/methods
8.
Eur Radiol ; 33(2): 1063-1087, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36194267

ABSTRACT

The European Society of Cardiovascular Radiology (ESCR) is the European specialist society of cardiac and vascular imaging. This society's highest priority is the continuous improvement, development, and standardization of education, training, and best medical practice, based on experience and evidence. The present intra-society consensus is based on the existing scientific evidence and on the individual experience of the members of the ESCR writing group on carotid diseases, the members of the ESCR guidelines committee, and the members of the executive committee of the ESCR. The recommendations published herein reflect the evidence-based society opinion of ESCR. We have produced a twin-papers consensus, indicated through the documents as respectively "Part I" and "Part II." The first document (Part I) begins with a discussion of features, role, indications, and evidence for CT and MR imaging-based diagnosis of carotid artery disease for risk stratification and prediction of stroke (Section I). It then provides an extensive overview and insight into imaging-derived biomarkers and their potential use in risk stratification (Section II). Finally, detailed recommendations about optimized imaging technique and imaging strategies are summarized (Section III). The second part of this consensus paper (Part II) is focused on structured reporting of carotid imaging studies with CT/MR. KEY POINTS: • CT and MR imaging-based evaluation of carotid artery disease provides essential information for risk stratification and prediction of stroke. • Imaging-derived biomarkers and their potential use in risk stratification are evolving; their correct interpretation and use in clinical practice must be well-understood. • A correct imaging strategy and scan protocol will produce the best possible results for disease evaluation.


Subject(s)
Atherosclerosis , Carotid Artery Diseases , Radiology , Stroke , Humans , Consensus , Tomography, X-Ray Computed/methods , Carotid Artery Diseases/diagnostic imaging , Magnetic Resonance Imaging , Reference Standards
9.
J Cardiovasc Magn Reson ; 25(1): 33, 2023 06 19.
Article in English | MEDLINE | ID: mdl-37331991

ABSTRACT

BACKGROUND: MRI T2 mapping has been proven to be sensitive to the level of blood oxygenation. We hypothesized that impaired exercise capacity in chronic heart failure is associated with a greater difference between right (RV) to left ventricular (LV) blood pool T2 relaxation times due to a higher level of peripheral blood desaturation, compared to patients with preserved exercise capacity and to healthy controls. METHODS: Patients with chronic heart failure (n = 70) who had undergone both cardiac MRI (CMR) and a 6-min walk test (6MWT) were retrospectively identified. Propensity score matched healthy individuals (n = 35) served as control group. CMR analyses included cine acquisitions and T2 mapping to obtain blood pool T2 relaxation times of the RV and LV. Following common practice, age- and gender-adjusted nominal distances and respective percentiles were calculated for the 6MWT. The relationship between the RV/LV T2 blood pool ratio and the results from 6MWT were evaluated by Spearman's correlation coefficients and regression analyses. Inter-group differences were assessed by independent t-tests and univariate analysis of variance. RESULTS: The RV/LV T2 ratio moderately correlated with the percentiles of nominal distances in the 6MWT (r = 0.66) while ejection fraction, end-diastolic and end-systolic volumes showed no correlation (r = 0.09, 0.07 and - 0.01, respectively). In addition, there were significant differences in the RV/LV T2 ratio between patients with and without significant post-exercise dyspnea (p = 0.001). Regression analyses showed that RV/LV T2 ratio was an independent predictor of the distance walked and the presence of post-exercise dyspnea (p < 0.001). CONCLUSION: The proposed RV/LV T2 ratio, obtained by two simple measurements on a routinely acquired four-chamber T2 map, was superior to established parameters of cardiac function to predict exercise capacity and the presence of post-exercise dyspnea in patients with chronic heart failure.


Subject(s)
Heart Failure , Ventricular Dysfunction, Left , Humans , Retrospective Studies , Exercise Tolerance , Predictive Value of Tests , Magnetic Resonance Imaging , Heart Failure/diagnostic imaging , Stroke Volume , Ventricular Function, Left , Ventricular Function, Right
10.
J Magn Reson Imaging ; 55(5): 1452-1458, 2022 05.
Article in English | MEDLINE | ID: mdl-34374157

ABSTRACT

BACKGROUND: Left-to-right (L-R) shunts are characterized by a pathological connection between high- and low-pressure systems, leading to a mixing of oxygen-rich blood with low oxygenated blood. They are typically diagnosed by phase-contrast cardiac magnetic resonance imaging (MRI) which requires extensive planning. T2 is sensitive to blood oxygenation and may be able to detect oxygenation differences between the left (LV) and right ventricles (RV) caused by L-R shunts. PURPOSE: To test the feasibility of routine T2 mapping to detect L-R shunts. STUDY TYPE: Retrospective. POPULATION: Patients with known L-R shunts (N = 27), patients with RV disease without L-R shunts (N = 21), and healthy volunteers (HV; N = 52). FIELD STRENGTH/SEQUENCE: 1.5 and 3 T/balanced steady-state free-precession (bSSFP) sequence (cine imaging), T2-prepared bSSFP sequence (T2 mapping), and velocity sensitized gradient echo sequence (phase-contrast MRI). ASSESSMENT: Aortic (Qs) and pulmonary (Qp) flow was measured by phase-contrast imaging, and the Qp/Qs ratio was calculated as a measure of shunt severity. T2 maps were used to measure T2 in the RV and LV and the RV/LV T2 ratio was calculated. Cine imaging was used to calculate RV end-diastolic volume index (RV-EDVi). STATISTICAL TESTS: Wilcoxon test, paired t-tests, Spearmen correlation coefficient, receiver operating curve (ROC) analysis. Significance level P < 0.05. RESULTS: The Qp/Qs and T2 ratios in L-R shunt patients (1.84 ± 0.84 and 0.89 ± 0.07) were significantly higher compared to those in patients with RV disease (1.01 ± 0.03 and 0.72 ± 0.10) and in HV (1.04 ± 0.04 and 0.71 ± 0.09). A T2 ratio of >0.78 showed a sensitivity, specificity, and negative predictive value of 100%, 73.9%, and 100%, respectively, for the detection of L-R shunts. The T2 ratio was strongly correlated with the severity of the shunt (r = 0.83). DATA CONCLUSION: RV/LV T2 ratio is an imaging biomarker that may be able to detect or rule-out L-R shunts. Such a diagnostic tool may prevent unnecessary phase-contrast acquisitions in cases with RV dilatation of unknown etiology. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.


Subject(s)
Heart Ventricles , Magnetic Resonance Imaging , Aorta , Heart Ventricles/diagnostic imaging , Humans , Retrospective Studies
11.
Eur Radiol ; 31(10): 7219-7230, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33779815

ABSTRACT

OBJECTIVES: To compare volumetric and functional parameters of the atria derived from highly accelerated compressed sensing (CS)-based cine sequences in comparison to conventional (Conv) cine imaging. METHODS: CS and Conv cine sequences were acquired in 101 subjects (82 healthy volunteers (HV) and 19 patients with heart failure with reduced ejection fraction (HFrEF)) using a 3T MR scanner in this single-center study. Time-volume analysis of the left (LA) and right atria (RA) were performed in both sequences to evaluate atrial volumes and function (total, passive, and active emptying fraction). Inter-sequence and inter- and intra-reader agreement were analyzed using correlation, intraclass correlation (ICC), and Bland-Altman analysis. RESULTS: CS-based cine imaging led to a 69% reduction of acquisition time. There was significant difference in atrial parameters between CS and Conv cine, e.g., LA minimal volume (LAVmin) (Conv 24.0 ml (16.7-32.7), CS 25.7 ml (19.2-35.2), p < 0.0001) or passive emptying fraction (PEF) (Conv 53.9% (46.7-58.4), CS 49.0% (42.0-54.1), p < 0.0001). However, there was high correlation between the techniques, yielding good to excellent ICC (0.76-0.99) and small mean of differences in Bland-Altman analysis (e.g. LAVmin - 2.0 ml, PEF 3.3%). Measurements showed high inter- (ICC > 0.958) and intra-rater (ICC > 0.934) agreement for both techniques. CS-based parameters (PEF AUC = 0.965, LAVmin AUC = 0.864) showed equivalent diagnostic ability compared to Conv cine imaging (PEF AUC = 0.989, LAVmin AUC = 0.859) to differentiate between HV and HFrEF. CONCLUSION: Atrial volumetric and functional evaluation using CS cine imaging is feasible with relevant reduction of acquisition time, therefore strengthening the role of CS in clinical CMR for atrial imaging. KEY POINTS: • Reliable assessment of atrial volumes and function based on compressed sensing cine imaging is feasible. • Compressed sensing reduces scan time and has the potential to overcome obstacles of conventional cine imaging. • No significant differences for subjective image quality, inter- and intra-rater agreement, and ability to differentiate healthy volunteers and heart failure patients were detected between conventional and compressed sensing cine imaging.


Subject(s)
Heart Failure , Acceleration , Heart Atria/diagnostic imaging , Humans , Image Interpretation, Computer-Assisted , Magnetic Resonance Imaging, Cine , Reproducibility of Results , Stroke Volume
12.
Eur J Anaesthesiol ; 38(4): 411-421, 2021 Apr 01.
Article in English | MEDLINE | ID: mdl-33399378

ABSTRACT

BACKGROUND: The treatment of haemorrhagic shock is a challenging task. Colloids have been regarded as standard treatment, but their safety and benefit have been the subject of controversial debates. Negative effects, including renal failure and increased mortality, have resulted in restrictions on their administration. The cerebral effects of different infusion regimens are largely unknown. OBJECTIVES: The current study investigated the impact of gelatine-polysuccinate, hydroxyethyl starch (HES) and balanced electrolyte solution (BES) on cerebral integrity, focusing on cerebral inflammation, apoptosis and blood flow in pigs. DESIGN: Randomised experimental study. SETTING: University-affiliated large animal research unit. ANIMALS: Twenty-four juvenile pigs aged 8 to 12 weeks. INTERVENTION: Haemorrhagic shock was induced by controlled arterial blood withdrawal to achieve a combination of relevant blood loss (30 to 40 ml kg-1) and haemodynamic deterioration. After 30 min of shock, fluid resuscitation was started with either gelatine-polysuccinate, HES or BES. The animals were then monitored for 4 h. MAIN OUTCOME MEASURES: Cerebral perfusion and diffusion were measured via arterial-spin-labelling MRI. Peripheral tissue perfusion was evaluated via white light spectroscopy. Cortical and hippocampal samples were collected at the end of the experiment. The numbers of cerebral cell nuclei were counted and mRNA expression of markers for cerebral apoptosis [glucose transporter protein type 1 (SLC2A), lipocalin 2 (LCN-2), aquaporin-4 (AQP4)] and inflammation [IL-6, TNF-α, glial fibrillary acidic protein (GFAP)] were determined. RESULTS: The three fluid protocols all stabilised the macrocirculation. Fluid resuscitation significantly increased the cerebral perfusion. Gelatine-polysuccinate and HES initially led to a higher cardiac output but caused haemodilution. Cerebral cell counts (as cells µm-2) were lower after colloid administration in the cortex (gelatine-polysuccinate, 1.8 ±â€Š0.3; HES, 1.9 ±â€Š0.4; each P < 0.05 vs. BES, 2.3 ±â€Š0.2) and the hippocampus (gelatine-polysuccinate, 0.8 ±â€Š0.2; HES, 0.9 ±â€Š0.2; each P < 0.05 vs. BES, 1.1 ±â€Š0.1). After gelatine-polysuccinate, the hippocampal SLC2A and GFAP were lower. After gelatine-polysuccinate, the cortical LCN-2 and TNF-α expression levels were increased (each P < 0.05 vs. BES). CONCLUSION: In a porcine model, fluid resuscitation by colloids, particularly gelatine-polysuccinate, was associated with the occurrence of cerebral injury. ETHICAL APPROVAL NUMBER: 23 177-07/G 15-1-092; 01/2016.


Subject(s)
Shock, Hemorrhagic , Animals , Fluid Therapy , Hydroxyethyl Starch Derivatives , Prospective Studies , Resuscitation , Shock, Hemorrhagic/drug therapy , Swine
13.
Eur Radiol ; 28(3): 1276-1284, 2018 Mar.
Article in English | MEDLINE | ID: mdl-28894923

ABSTRACT

OBJECTIVES: To evaluate differences in myocardial strain between pectus excavatum (PE) patients and healthy subjects (HS) assessed by cardiac MRI using the feature-tracking algorithm. METHODS: Cardiac MRI was performed in 14 PE patients and 14 HS (9:5 male to female in each group; age 11-30 years) using a 3T scanner. Post-examination analysis included manual biventricular contouring with volumetry and ejection fraction measurement by two independent radiologists. Dedicated software was used for automated strain assessment. RESULTS: In five of the PE patients, the right ventricular ejection fraction was slightly impaired (40-44 %). PE patients had a significantly higher left ventricular longitudinal strain (P=0.004), mid (P=0.035) and apical (P=0.001) circumferential strain as well as apical circumferential strain rate (P=0.001), mid right ventricular circumferential strain (P=0.008) and strain rate (P=0.035), and apical right ventricular circumferential strain (P=0.012) and strain rate (P=0.044) than HS. The right ventricular longitudinal strain and strain rate did not differ significantly between PE patients and HS. CONCLUSIONS: Myocardial strain differs significantly between PE patients and HS. Higher myocardial strain in the mid and apical ventricles of PE patients indicates a compensation mechanism to enhance ventricular output against basal sternal compression. KEY POINTS: • The right ventricle is frequently affected by the pectus excavatum deformity. • Cardiac MRI revealed differences in myocardial strain in pectus excavatum patients. • Pectus excavatum patients exhibited higher strain in the mid/apical ventricles. • A compensation mechanism to enhance ventricular output against sternal compression is possible.


Subject(s)
Funnel Chest/diagnosis , Heart Ventricles/diagnostic imaging , Magnetic Resonance Imaging, Cine/methods , Myocardium/pathology , Ventricular Dysfunction, Right/diagnosis , Ventricular Function, Right/physiology , Adolescent , Adult , Child , Female , Funnel Chest/complications , Funnel Chest/physiopathology , Healthy Volunteers , Heart Ventricles/physiopathology , Humans , Male , Pilot Projects , Ventricular Dysfunction, Right/etiology , Ventricular Dysfunction, Right/physiopathology , Young Adult
16.
BMC Cancer ; 16(1): 758, 2016 Sep 29.
Article in English | MEDLINE | ID: mdl-27681525

ABSTRACT

BACKGROUND: Arterial hyperenhancement and washout on computed tomography and magnetic resonance imaging (MRI) are described by all major guidelines as specific criteria for non-invasive diagnosis of hepatocellular carcinoma (HCC). However, publications on the quantitative assessment of washout in MRI are lacking. Therefore, we evaluated a method for quantitatively measuring and defining washout in MRI in order to determine a cutoff value that allows objective HCC diagnosis. METHODS: We analyzed all patients who underwent liver transplantation for cirrhosis or liver resection for HCC at our institution between 2003 and 2014. Washout was quantitatively investigated by placing a 25-mm2 region of interest (ROI) over each nodule and two 25-mm2 ROIs over adjacent liver parenchyma. The percentage signal ratio (PSR = 100 × ratio of signal intensity of adjacent liver to that of the lesion) was calculated for each series in both groups. Accordingly, this quantitative measurement was compared to a qualitative approach. RESULTS: A total of 16 hypervascularized non-HCC nodules and 69 HCC nodules were identified. Interobserver reliability was reasonably good for the measurement of PSRs and readers showed a substantial agreement for the qualitative assessment. In the HCC group, the median PSR was 116.2 at equilibrium and 112.9 in the delayed phase. In the non-HCC group, the median PSR was 93.8 at equilibrium and 96.0 in the delayed phase. Receiver operating characteristic analysis indicated areas under the curve of 0.902 (p < 0.001) and 0.873 (p < 0.001) at equilibrium and in the delayed phase. PSR values of 102 at equilibrium and 101.5 in the delayed phase led to the highest Youden's index of 0.82 and 0.77, respectively. These PSR cutoffs yielded sensitivities of 82 and 77 %, respectively, with specificities of 100 %. The sensitivity for the qualitative assessment of washout was 88 and 93 % and the specificity was 48 and 56 %. For the classification of HCC, sensitivity yielded 95 and 97 % and specificity was 68 and 56 %, respectively. CONCLUSION: Quantitatively measuring HCC washout in MRI is easy and reproducible. It can objectify and support diagnosis of HCC. However, the quantitative measurement of washout can only serve as one of several components of HCC assessment.

17.
Eur Radiol ; 25(7): 2004-14, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25693662

ABSTRACT

OBJECTIVES: To evaluate the incidence, management, and outcome of visceral artery aneurysms (VAA) over one decade. METHODS: 233 patients with 253 VAA were analyzed according to location, diameter, aneurysm type, aetiology, rupture, management, and outcome. RESULTS: VAA were localized at the splenic artery, coeliac trunk, renal artery, hepatic artery, superior mesenteric artery, and other locations. The aetiology was degenerative, iatrogenic after medical procedures, connective tissue disease, and others. The rate of rupture was much higher in pseudoaneurysms than true aneurysms (76.3% vs.3.1%). Fifty-nine VAA were treated by intervention (n = 45) or surgery (n = 14). Interventions included embolization with coils or glue, covered stents, or combinations of these. Thirty-five cases with ruptured VAA were treated on an emergency basis. There was no difference in size between ruptured and non-ruptured VAA. After interventional treatment, the 30-day mortality was 6.7% in ruptured VAA compared to no mortality in non-ruptured cases. Follow-up included CT and/or MRI after a mean period of 18.0 ± 26.8 months. The current status of the patient was obtained by a structured telephone survey. CONCLUSIONS: Pseudoaneurysms of visceral arteries have a high risk for rupture. Aneurysm size seems to be no reliable predictor for rupture. Interventional treatment is safe and effective for management of VAA. KEY POINTS: • Diagnosis of visceral artery aneurysms is increasing due to CT and MRI. • Diameter of visceral arterial aneurysms is no reliable predictor for rupture. • False aneurysms/pseudoaneurysms and symptomatic cases need emergency treatment. • Interventional treatment is safe and effective.


Subject(s)
Aneurysm/diagnosis , Arteries , Viscera/blood supply , Adolescent , Adult , Aged , Aged, 80 and over , Aneurysm/surgery , Aneurysm, False/diagnosis , Aneurysm, False/surgery , Aneurysm, Ruptured/diagnosis , Celiac Artery , Embolization, Therapeutic/methods , Endovascular Procedures/methods , Female , Hepatic Artery , Humans , Magnetic Resonance Angiography , Male , Mesenteric Artery, Superior , Middle Aged , Renal Artery , Retrospective Studies , Splenic Artery , Tertiary Care Centers , Treatment Outcome , Young Adult
18.
Semin Respir Crit Care Med ; 35(1): 99-111, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24481764

ABSTRACT

Pulmonary hypertension is defined as a resting mean pulmonary arterial pressure of 25 mm Hg or more determined at right heart catheterization. The challenges for imaging in patients with suspected PH are fivefold: the imaging modality should have a high diagnostic accuracy with regard to the presence of PH; it should be able to characterize the underlying disease, and allow for quantification of its extent by measuring pulmonary hemodynamics. Finally, it should provide prognostic information, and can be used for monitoring of therapy. There have been tremendous improvements in assessment of PH by computed tomography (CT) and magnetic resonance (MR) technology in recent years. This overview tries to elucidate the potential role of each imaging modality and summarizes the most important results that have been achieved so far. In general, after implementation of multidetector technology, CT is superior to MR in assessment of parenchymal and vascular pathologies of the lung, and with electrocardiogram-triggered data acquisition allows for assessment of cardiac structures. The implementation of iodine maps as surrogate for lung perfusion will enable functional assessment of lung perfusion by CT. MR imaging is the reference standard for assessment of cardiac structure and function and allows for physiologic assessment of the pulmonary vasculature. New developments show that with MR techniques, an estimation of hemodynamic parameters such as mean pulmonary arterial pressure and pulmonary vascular resistance will be possible. Actually, CT and MR imaging should be considered as complementary investigations providing comprehensive information in patients with pulmonary hypertension.


Subject(s)
Hypertension, Pulmonary/diagnosis , Magnetic Resonance Imaging/methods , Tomography, X-Ray Computed/methods , Arterial Pressure/physiology , Cardiac Catheterization , Diagnostic Imaging/methods , Hemodynamics , Humans , Hypertension, Pulmonary/physiopathology , Vascular Resistance/physiology
19.
Radiologie (Heidelb) ; 64(2): 134-141, 2024 Feb.
Article in German | MEDLINE | ID: mdl-37947866

ABSTRACT

Posttraumatic instability accounts for more than 95% of all shoulder instabilities with the highest incidence in patients between 20 and 30 years of age. In this age group, lesions of the capsulolabral complex are the most common sequelae after the first shoulder dislocation. Typical acute findings are the Bankart and Perthes lesions and humeral avulsion of the glenohumeral ligament (HAGL). Chronic sequelae are anterior labroligamentous periosteal sleeve avulsion (ALPSA) lesions, and nonclassifiable lesions with deficient anterioinferior labrum and glenohumeral ligaments. Recently, quantification of Hill-Sachs and bony Bankart lesions with glenoid defects have become the focus of interest: bipolar bone loss has emerged to be one important factor of recurrent instability that has not been addressed during the first stabilizing operation. The glenoid track concept emphasizes the importance of bipolar bone loss, where the glenoid track refers to the contact area between the humeral head and the glenoid at the end-range of motion in abduction, extension and external rotation. Any lesion of the humeral head that extends beyond the glenoid track is considered high risk for engagement of the humeral head at the glenoid margin with subsequent dislocation. Both the Hill-Sachs interval and the glenoid track can be determined using computed tomography (CT) and magnetic resonance imaging and, thus, help to define the status of the shoulder (on-track vs. off-track), which is prerequisite for planning the appropriate operative procedure. Similar tendencies also exist for posttraumatic posterior instabilities which are much rarer.


Subject(s)
Joint Instability , Shoulder Dislocation , Shoulder Joint , Humans , Shoulder Joint/diagnostic imaging , Shoulder Joint/surgery , Joint Instability/diagnostic imaging , Joint Instability/surgery , Shoulder , Shoulder Dislocation/diagnostic imaging , Shoulder Dislocation/surgery , Shoulder Dislocation/complications , Humeral Head/pathology , Humeral Head/surgery
20.
J Thorac Imaging ; 39(2): 127-135, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-37982533

ABSTRACT

BACKGROUND: Cardiac magnetic resonance imaging protocols have been adapted to fit the needs for faster, more efficient acquisitions, resulting in the development of highly accelerated, compressed sensing-based (CS) sequences. The aim of this study was to evaluate intersoftware and interacquisition differences for postprocessing software applied to both CS and conventional cine sequences. MATERIALS AND METHODS: A total of 106 individuals (66 healthy volunteers, 40 patients with dilated cardiomyopathy, 51% female, 38±17 y) underwent cardiac magnetic resonance at 3T with retrospectively gated conventional cine and CS sequences. Postprocessing was performed using 2 commercially available software solutions and 1 research prototype from 3 different developers. The agreement of clinical and feature-tracking strain parameters between software solutions and acquisition types was assessed by Bland-Altmann analyses and intraclass correlation coefficients. Differences between softwares and acquisitions were assessed using Kruskal-Wallis analysis of variances. In addition, receiver operating characteristic curve-derived cutoffs were used to evaluate whether sequence-specific cutoffs influence disease classification. RESULTS: There were significant intersoftware ( P <0.002 for all except LV end-diastolic volume per body surface area) and interacquisition differences ( P <0.02 for all except end-diastolic volume per body surface area from Neosoft, left ventricular mass per body surface area from cvi42 and TrufiStrain and global circumferential strain from Neosoft). However, the intraclass correlation coefficients between acquisitions were strong-to-excellent for all parameters (all ≥0.81). In comparing individual softwares to a pooled mean, Bland-Altmann analyses revealed smaller magnitudes of bias for cine acquisition than for CS acquisition. In addition, the application of conventional cutoffs to CS measurements did not result in the false reclassification of patients. CONCLUSION: Significantly lower magnitudes of strain and volumetric parameters were observed in retrospectively gated CS acquisitions, despite strong-to-excellent agreement amongst software solutions and acquisition types. It remains important to be aware of the acquisition type in the context of follow-up examinations, where different cutoffs might lead to misclassifications.


Subject(s)
Image Interpretation, Computer-Assisted , Magnetic Resonance Imaging, Cine , Humans , Female , Male , Retrospective Studies , Magnetic Resonance Imaging, Cine/methods , Image Interpretation, Computer-Assisted/methods , Reproducibility of Results , Heart Ventricles , Ventricular Function, Left
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