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1.
J Cardiovasc Magn Reson ; 25(1): 40, 2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37474977

RESUMO

Hemodynamic assessment is an integral part of the diagnosis and management of cardiovascular disease. Four-dimensional cardiovascular magnetic resonance flow imaging (4D Flow CMR) allows comprehensive and accurate assessment of flow in a single acquisition. This consensus paper is an update from the 2015 '4D Flow CMR Consensus Statement'. We elaborate on 4D Flow CMR sequence options and imaging considerations. The document aims to assist centers starting out with 4D Flow CMR of the heart and great vessels with advice on acquisition parameters, post-processing workflows and integration into clinical practice. Furthermore, we define minimum quality assurance and validation standards for clinical centers. We also address the challenges faced in quality assurance and validation in the research setting. We also include a checklist for recommended publication standards, specifically for 4D Flow CMR. Finally, we discuss the current limitations and the future of 4D Flow CMR. This updated consensus paper will further facilitate widespread adoption of 4D Flow CMR in the clinical workflow across the globe and aid consistently high-quality publication standards.


Assuntos
Sistema Cardiovascular , Humanos , Velocidade do Fluxo Sanguíneo , Valor Preditivo dos Testes , Coração , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética
2.
J Cardiovasc Magn Reson ; 25(1): 22, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36978131

RESUMO

BACKGROUND: Different software programs are available for the evaluation of 4D Flow cardiovascular magnetic resonance (CMR). A good agreement of the results between programs is a prerequisite for the acceptance of the method. Therefore, the goal was to compare quantitative results from a cross-over comparison in individuals examined on two scanners of different vendors analyzed with four postprocessing software packages. METHODS: Eight healthy subjects (27 ± 3 years, 3 women) were each examined on two 3T CMR systems (Ingenia, Philips Healthcare; MAGNETOM Skyra, Siemens Healthineers) with a standardized 4D Flow CMR sequence. Six manually placed aortic contours were evaluated with Caas (Pie Medical Imaging, SW-A), cvi42 (Circle Cardiovascular Imaging, SW-B), GTFlow (GyroTools, SW-C), and MevisFlow (Fraunhofer Institute MEVIS, SW-D) to analyze seven clinically used parameters including stroke volume, peak flow, peak velocity, and area as well as typically scientifically used wall shear stress values. Statistical analysis of inter- and intrareader variability, inter-software and inter-scanner comparison included calculation of absolute and relative error (ER), intraclass correlation coefficient (ICC), Bland-Altman analysis, and equivalence testing based on the assumption that inter-software differences needed to be within 80% of the range of intrareader differences. RESULTS: SW-A and SW-C were the only software programs showing agreement for stroke volume (ICC = 0.96; ER = 3 ± 8%), peak flow (ICC: 0.97; ER = -1 ± 7%), and area (ICC = 0.81; ER = 2 ± 22%). Results from SW-A/D and SW-C/D were equivalent only for area and peak flow. Other software pairs did not yield equivalent results for routinely used clinical parameters. Especially peak maximum velocity yielded poor agreement (ICC ≤ 0.4) between all software packages except SW-A/D that showed good agreement (ICC = 0.80). Inter- and intrareader consistency for clinically used parameters was best for SW-A and SW-D (ICC = 0.56-97) and worst for SW-B (ICC = -0.01-0.71). Of note, inter-scanner differences per individual tended to be smaller than inter-software differences. CONCLUSIONS: Of all tested software programs, only SW-A and SW-C can be used equivalently for determination of stroke volume, peak flow, and vessel area. Irrespective of the applied software and scanner, high intra- and interreader variability for all parameters have to be taken into account before introducing 4D Flow CMR in clinical routine. Especially in multicenter clinical trials a single image evaluation software should be applied.


Assuntos
Imageamento por Ressonância Magnética , Software , Humanos , Feminino , Reprodutibilidade dos Testes , Valor Preditivo dos Testes , Aorta
3.
Neurol Res Pract ; 4(1): 15, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35462557

RESUMO

BACKGROUND: Anti-NMDA-receptor (anti-NMDAR) encephalitis is often associated with ovarian teratoma (OT). The best management of anti-NMDAR encephalitis patients with normal imaging studies (pelvic ultrasound/MRI) but clinically high risk of OT (e.g., female, adult, black) is unclear. We report on the surprising diagnostic quest in a young black woman with anti-NMDAR encephalitis, in whom invasive procedures could finally disclose two OTs that were hidden from the initial non-invasive diagnostics. CASE REPORT: The patient presented with a one-week history of psychotic symptoms, developing oro-facial dyskinesia, seizures and coma, eventually requiring mechanical ventilation. NMDA-receptor antibodies were positive in serum and cerebrospinal fluid. Pelvic MRI and transabdominal ultrasound were normal. Exploratory laparoscopy was also unremarkable at first, but due to a suspicious echogenic mass (15 mm) in the right ovary on perioperative transvaginal ultrasound, an ovarian incision was performed which led to the detection of a first OT and its removal via ovarian-preserving cystectomy. Following a severe therapy-refractory clinical course despite aggressive immunotherapy and tumor removal, 6 months later bilateral oophorectomy was performed as ultima ratio, disclosing a second micro-OT (6 mm) in the left ovary. Unfortunately, the patient has not improved clinically yet. CONCLUSIONS: In therapy-refractory anti-NMDAR encephalitis with high risk of OT, small and bilateral OTs hidden from primary non-invasive diagnostics should be considered, which may trigger further invasive diagnostic procedures.

4.
Rofo ; 194(6): 644-651, 2022 06.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-35439829

RESUMO

PURPOSE: During the SARS-CoV-2 pandemic, higher education worldwide had to switch to digital formats. The purpose of this study was to evaluate CoRad-19, a digital teaching tool created by the German Radiological Society for medical students during the COVID-19 pandemic. MATERIALS AND METHODS: A total of 13 German-speaking universities implemented CoRad-19 in their curriculum and partially or completely replaced their classes with the online courses. Previous experience and contact with radiology and the participants' opinions regarding the medium of e-learning were surveyed using a custom questionnaire. The subjective level of knowledge regarding the individual modules was also surveyed before and after participation to measure learning effects. The data of 994 medical students from the participating sites were analyzed and compared intraindividually using the Friedman test. RESULTS: From 4/1/2020-10/1/2020, 451 complete data sets from a total of 994 surveys were included. E-learning was rated "very useful" both before and after course participation (4 [IQR 3-4], p = 0.527, r = 0.16). E-learning as a method was also rated as a "very good" medium both before and after participation (4 [IQR 3-4], p = 0.414, r = 0.17). After participation, participants rated radiology as particularly suitable for digital teaching (before: 3 [IQR 3-4] vs. after 4 [IQR 3-4], p = 0.005, r = 0.6). Significant learning gains were measurable in all course modules (p ≤ 0.009). Post-hoc analysis showed interest in radiology to increase significantly after course participation (p = 0.02). CONCLUSION: In the representative survey, significant learning effects were observed in all course modules. In addition, it should be particularly emphasized that the students' interest in radiology was increased by course participation. Thus, the German Radiological Society provided significant support to German-speaking medical faculties with respect to maintaining excellent education using CoRad-19. KEY POINT: · Co-Rad-19 course participation results in measurable subjective learning effects and increases student interest in radiology.. CITATION FORMAT: · Brendlin AS, Molwitz I, Oechtering TH et al. CoRad-19 - Modular Digital Teaching during the SARS-CoV-2 Pandemic. Fortschr Röntgenstr 2022; 194: 644 - 651.


Assuntos
COVID-19 , Estudantes de Medicina , Currículo , Humanos , Pandemias , SARS-CoV-2 , Ensino
5.
Eur J Cardiothorac Surg ; 62(1)2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34409435

RESUMO

OBJECTIVES: This is a comprehensive analysis of haemodynamics after valve-sparing aortic root replacement (VSARR) with anatomically curved prosthesis (CP) compared to straight prosthesis (SP) and age-matched volunteers (VOL) using 4D flow MRI (time-resolved three-dimensional magnetic resonance phase-contrast imaging). METHODS: Nine patients with 90° CP, nine patients with SP, and twelve VOL were examined with 4D flow MRI. Analyses included various characteristic anatomical, qualitative and quantitative haemodynamic parameters. RESULTS: Grading of secondary flow patterns was lower in CP patients than in SP patients (P = 0.09) and more comparable to VOL, albeit not reaching statistical significance. However, it was easy to differentiate between VSARR patients and healthy volunteers: Patients more often had angular aortic arches (CP: 89%, SP: 100%; VOL: 17%; P ≤ 0.002), increased average curvature (CP: 0.17/cm [0.15, 0.18]; SP: 0.15/cm [0.14, 0.16]; VOL: 0.14/cm [0.13, 0.16]; P ≤ 0.007; values given as median [interquartile range]), and more secondary flow patterns (CP: 3 [2, 4] SP: 3 [2, 3] VOL: 2 [1, 2]; P < 0.01). Maximum circulation (CP: 142.7 cm2/s [116.1, 187.3]; SP: 101.8 cm2/s [77.7, 132.5]; VOL: 42.8cm2/s [39.3, 65.6]; P ≤ 0.002), maximum helicity density (CP: 9.6 m/s2 [9.3, 23.9]; SP: 9.7 m/s2 [8.6, 12.5]; VOL 4.9 m/s2 [4.2, 7.7]; P ≤ 0.007), and wall shear stress gradient (e.g., proximal ascending aorta CP: 0.97 N/m2 [0.54, 1.07]; SP: 1.08 N/m2 [0.74, 1.24]; VOL: 0.41 N/m2 [0.32, 0.60]; P ≤ 0.01) were increased in patients. One CP patient had a round aortic arch with physiological haemodynamic parameters. CONCLUSIONS: The restoration of physiological aortic configuration and haemodynamics was not fully achieved with the curved prostheses in our study cohort. However, there was a tendency towards improved haemodynamic conditions in the patients with curved prostheses overall but without statistical significance. A single patient with a CP and near-physiological configuration of the thoracic aorta underlines the importance of optimizing postoperative geometric conditions for allowing for physiological haemodynamics and cardiovascular energetics after VSARR.


Assuntos
Valva Aórtica , Próteses Valvulares Cardíacas , Aorta/diagnóstico por imagem , Aorta/fisiologia , Aorta/cirurgia , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Velocidade do Fluxo Sanguíneo/fisiologia , Hemodinâmica/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos
6.
J Cancer Res Clin Oncol ; 148(7): 1789-1801, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34415426

RESUMO

BACKGROUND: The composition of the tumor microenvironment (TME) is conditioned by immunity and the inflammatory response. Nutritional and inflammation-based risk scores have emerged as relevant predictors of survival outcome across a variety of hematological malignancies. METHODS: In this retrospective multicenter trial, we ascertained the prognostic impact of established nutritional and inflammation-based risk scores [Glasgow Prognostic Score (GPS), C-reactive-protein/albumin ratio (CAR), neutrophil-lymphocyte ratio (NLR), prognostic nutritional index (PNI), and prognostic index (PI)] in 209 eligible patients with histologically confirmed CD20+ follicular lymphoma (FL) of WHO grade 1 (37.3%), 1-2 (16.3%), 2 (26.8%) or 3A (19.8%) admitted to the participating centers between January 2000 and December 2019. Characteristics significantly associated with overall or progression-free survival (OS, PFS) upon univariate analysis were subsequently included in a Cox proportional hazard model. RESULTS: In the study cohort, the median age was 63 (range 22-90 years). The median follow-up period covered 99 months. The GPS and the CAR were identified to predict survival in FL patients. The GPS was the only independent predictor of OS (p < 0.0001; HR 2.773; 95% CI 1.630-4.719) and PFS (p = 0.001; HR 1.995; 95% CI 1.352-2.944) upon multivariate analysis. Additionally, there was frequent occurrence of progression of disease within 24 months (POD24) in FL patients with a calculated GPS of 2. CONCLUSION: The current results indicate that the GPS predicts especially OS in FL patients. Moreover, GPS was found to display disease-specific effects in regard to FL progression. These findings and potential combinations with additional established prognosticators should be further validated within prospective clinical trials.


Assuntos
Linfoma Folicular , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD20/imunologia , Humanos , Inflamação , Linfoma Folicular/tratamento farmacológico , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Microambiente Tumoral , Adulto Jovem
7.
Eur Radiol ; 32(1): 690-701, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34170365

RESUMO

OBJECTIVES: To develop and validate a deep learning-based algorithm for segmenting and quantifying the physiological and diseased aorta in computed tomography angiographies. METHODS: CTA exams of the aorta of 191 patients (68.1 ± 14 years, 128 male), performed between 2015 and 2018, were retrospectively identified from our imaging archive and manually segmented by two investigators. A 3D U-Net model was trained on the data, which was divided into a training, a validation, and a test group at a ratio of 7:1:2. Cases in the test group (n = 41) were evaluated to compare manual and automatic segmentations. Dice similarity coefficient (DSC), mean surface distance (MSD), and Hausdorff surface distance (HSD) were extracted. Maximum diameter, effective diameter, and area were quantified and compared between both segmentations at eight anatomical landmarks, and at the maximum area of an aneurysms if present (n = 14). Statistics included error calculation, intraclass correlation coefficient, and Bland-Altman analysis. RESULTS: A DSC of 0.95 [0.94; 0.95] and an MSD of 0.76 [0.06; 0.99] indicated close agreement between segmentations. HSD was 8.00 [4.47; 10.00]. The largest absolute errors were found in the ascending aorta with 0.8 ± 1.5 mm for maximum diameter and at the coeliac trunk with - 30.0 ± 81.6 mm2 for area. Results for absolute errors in aneurysms were - 0.5 ± 2.3 mm for maximum diameter, 0.3 ± 1.6 mm for effective diameter, and 64.9 ± 114.9 mm2 for area. ICC showed excellent agreement (> 0.9; p < 0.05) between quantitative measurements. CONCLUSIONS: Automated segmentation of the aorta on CTA data using a deep learning algorithm is feasible and allows for accurate quantification of the aortic lumen even if the vascular architecture is altered by disease. KEY POINTS: • A deep learning-based algorithm can automatically segment the aorta, mostly within acceptable margins of error, even if the vascular architecture is altered by disease. • Quantifications performed in the segmentations were mostly within clinically acceptable limits, even in pathologically altered segments of the aorta.


Assuntos
Angiografia por Tomografia Computadorizada , Aprendizado Profundo , Algoritmos , Aorta/diagnóstico por imagem , Humanos , Masculino , Estudos Retrospectivos
8.
Front Med (Lausanne) ; 8: 691618, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34291066

RESUMO

Immune checkpoint inhibitor (ICI) therapy has revolutionized the treatment of several human malignancies, particularly metastatic skin cancer. However, immune-related myocarditis (irM), an immune-mediated adverse event (irAE), is often fatal. In the absence of a reliable biomarker, measurement of pre-ICI therapy serum troponin concentration has been proposed to identify patients at risk of developing irM, although real-world studies examining this strategy are lacking. Thus, we retrospectively analyzed the case records of all patients who commenced ICI therapy between January 2018 and December 2019 in a single university skin cancer center (n = 121) to (i) determine the incidence of irM, (ii) establish the frequency of pretreatment serum hsTnT elevations, and (iii) to establish whether this identified patients who subsequently developed irM. Only one patient developed irM, resulting in an overall incidence of 0.8%. Pretreatment hsTnT was measured in 47 patients and was elevated in 13 (28%). Elevated serum hsTnT concentrations were associated with chronic renal failure (p = 0.02) and diabetes (p < 0.0002). Pretreatment hsTnT was not elevated in the patient who developed fulminant irM. Pre-immunotherapy serum hsTnT concentrations were often asymptomatically elevated in patients with advanced skin cancer, none of whom subsequently developed irM during ICI therapy. However, large studies are required to assess the positive and negative predictive values of hsTnT for the development of irM. In the meantime, elevated hsTnT concentrations should be investigated before initiation of immunotherapy and closely monitored during early treatment cycles, where the risk of irM is greatest.

10.
J Am Heart Assoc ; 10(9): e018881, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33899498

RESUMO

Background Intravenous morphine administration can adversely affect platelet inhibition induced by P2Y12 receptor inhibitors after acute myocardial infarction. In contrast, some evidence suggests that opioid agonists may have cardioprotective effects on the myocardium. The aim of this prospective, randomized MonAMI (Impact of Morphine Treatment With and Without Metoclopramide Coadministration on Platelet Inhibition in Acute Myocardial Infarction) trial was, therefore, to investigate the impact of morphine with or without metoclopramide coadministration on myocardial and microvascular injury. Methods and Results Patients with acute myocardial infarction (n=138) were assigned in a 1:1:1 ratio to ticagrelor 180 mg plus: (1) intravenous morphine 5 mg (morphine group); (2) intravenous morphine 5 mg and metoclopramide 10 mg (morphine+metoclopramide group); or (3) intravenous placebo (control group) administered before primary percutaneous coronary intervention. Cardiac magnetic resonance imaging was performed in 104 patients on day 1 to 4 after the index event. Infarct size was significantly smaller in the morphine only group as compared with controls (percentage of left ventricular mass, 15.5 versus 17.9; P=0.047). Furthermore, the number of patients with microvascular obstruction was significantly lower after morphine administration (28% versus 54%; P=0.022) and the extent of microvascular obstruction was smaller (percentage of left ventricular mass, 0 versus 0.74; P=0.037). In multivariable regression analysis, morphine administration was independently associated with a reduced risk for the occurrence of microvascular obstruction (odds ratio, 0.37; 95% CI, 0.14-0.93 [P=0.035]). There was no significant difference in infarct size (P=0.491) and extent (P=0.753) or presence (P=0.914) of microvascular obstruction when comparing the morphine+metoclopramide group with the control group. Conclusions In this randomized study, intravenous administration of morphine before primary percutaneous coronary intervention resulted in a significant reduction of myocardial and microvascular damage following acute myocardial infarction. This effect was not observed in the morphine plus metoclopramide group. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02627950.


Assuntos
Circulação Coronária/fisiologia , Metoclopramida/administração & dosagem , Microcirculação/efeitos dos fármacos , Morfina/administração & dosagem , Traumatismo por Reperfusão/prevenção & controle , Infarto do Miocárdio com Supradesnível do Segmento ST/tratamento farmacológico , Vasoconstrição/efeitos dos fármacos , Idoso , Analgésicos Opioides/administração & dosagem , Angiografia Coronária , Antagonistas dos Receptores de Dopamina D2/administração & dosagem , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Imagem Cinética por Ressonância Magnética/métodos , Masculino , Microcirculação/fisiologia , Pessoa de Meia-Idade , Estudos Prospectivos , Traumatismo por Reperfusão/diagnóstico , Traumatismo por Reperfusão/fisiopatologia , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Método Simples-Cego
11.
Breast Cancer Res ; 23(1): 36, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33736679

RESUMO

BACKGROUND: Prediction of histological tumor size by post-neoadjuvant therapy (NAT) ultrasound and magnetic resonance imaging (MRI) was evaluated in different breast cancer subtypes. METHODS: Imaging was performed after 12-week NAT in patients enrolled into three neoadjuvant WSG ADAPT subtrials. Imaging performance was analyzed for prediction of residual tumor measuring ≤10 mm and summarized using positive (PPV) and negative (NPV) predictive values. RESULTS: A total of 248 and 588 patients had MRI and ultrasound, respectively. Tumor size was over- or underestimated by < 10 mm in 4.4% and 21.8% of patients by MRI and in 10.2% and 15.8% by ultrasound. Overall, NPV (proportion of correctly predicted tumor size ≤10 mm) of MRI and ultrasound was 0.92 and 0.83; PPV (correctly predicted tumor size > 10 mm) was 0.52 and 0.61. MRI demonstrated a higher NPV and lower PPV than ultrasound in hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-positive and in HR-/HER2+ tumors. Both methods had a comparable NPV and PPV in HR-/HER2- tumors. CONCLUSIONS: In HR+/HER2+ and HR-/HER2+ breast cancer, MRI is less likely than ultrasound to underestimate while ultrasound is associated with a lower risk to overestimate tumor size. These findings may help to select the most optimal imaging approach for planning surgery after NAT. TRIAL REGISTRATION: Clinicaltrials.gov , NCT01815242 (registered on March 21, 2013), NCT01817452 (registered on March 25, 2013), and NCT01779206 (registered on January 30, 2013).


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imageamento por Ressonância Magnética , Ultrassonografia Mamária , Adulto , Idoso , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasia Residual , Valor Preditivo dos Testes , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Carga Tumoral
12.
Cardiovasc Intervent Radiol ; 44(7): 1109-1115, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33723668

RESUMO

PURPOSE: To evaluate heating of a redilatable stent for the treatment of aortic coarctation in neonates and small children in the new imaging modality magnetic particle imaging and established magnetic resonance imaging. MATERIALS AND METHODS: The cobalt-chromium stent (BabyStent, OSYPKA AG, Rheinfelden, Germany) has a stent design which allows for redilatation and adjustment of the diameter from 6 to 16 mm for a use in aortic coarctation. The stent loses its radial integrity while opening at predetermined breaking points at a diameter of 14 mm or 16 mm, respectively. We measured the temperature increase in the stent at different diameters during 7-min magnetic particle imaging and magnetic resonance imaging scans with fiber optic thermometers under static conditions surrounded by air. In magnetic particle imaging, stents with diameters from 6 to 16 mm were tested while in magnetic resonance imaging only stents with diameters of 6 mm and 14 mm were investigated exemplarily. RESULT: In magnetic particle imaging, the measured temperature differences increased up to 4.7 K with growing diameters, whereas the opened stents with discontinuous struts at 14 and 16 mm showed only minimal heating of max. 0.5 K. In contrast to magnetic particle imaging, our measurements showed no heating of the stents during magnetic resonance imaging under identical conditions. CONCLUSION: The BabyStent did show only slight heating in magnetic particle imaging and no detectable temperature increase in magnetic resonance imaging.


Assuntos
Coartação Aórtica/cirurgia , Implante de Prótese Vascular/métodos , Calefação/métodos , Imageamento por Ressonância Magnética/métodos , Imagens de Fantasmas , Stents , Coartação Aórtica/diagnóstico , Humanos , Resultado do Tratamento
13.
Rofo ; 193(8): 919-927, 2021 Aug.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-33535262

RESUMO

PURPOSE: In light of the steadily increasing need for economical efficacy and capacity utilization it was the aim of this proof-of-concept work to implement an automated logfile-based analysis tool for MRI scanner utilization and to establish a process analysis. As a primary step, analyses of scanner and protocol utilization, parametrization of protocol processes, their durations, age dependency, and scan efficacy were to be tested. MATERIALS AND METHODS: Logfiles were continuously extracted from a 1.5 T MR scanner (Philips Achieva) and automatically explored for relevant scan parameters. Parameters were extracted into a database and logically combined to protocol parameters. Visualization was achieved using PowerBI (Microsoft, USA). Data aggregation comprised a day-based and protocol-based strategy. In addition, age- and regional-based testing was performed. The frequency of protocol usage was evaluated and those protocols with frequent usage compared regarding efficacy to those rarely used. RESULTS: After successful technical implementation, 3659 MR exams were available for further analysis. Out of a plethora of parameters, those relevant to the understanding of the scan process were identified. The initial results mirror the daily scanner usage and allow identifying, e. g., shortened scanner usage on Fridays or longer examination times in children. A scan efficacy of 69.6 ±â€Š17.6 % excluding preparation process was identified as a parameter with high potential to be optimized in daily routine. CONCLUSION: The logfile-based analysis of MR scanner processes was successfully introduced and holds the promise to be extended into a comprehensive analytic tool for the analysis and optimization of scanner processes. In combination with other variables from the departmental or institutional infrastructure or patient-specific information such tool may be developed into a intelligent steering tool. KEY POINTS: · The automated log file analysis of MR-scanner processes was successfully introduced. · The log file-analysis allows for a detailed analysis of scanner processes. · From a log file-analysis, there is potential benefit to users, applications specialists and developers. CITATION FORMAT: · Frydrychowicz A, Boppel T, Sieber V et al. Automatic, log file-based process analysis of a clinical 1.5T MR scanner: a proof-of-concept study. Fortschr Röntgenstr 2021; 193: 919 - 927.


Assuntos
Imageamento por Ressonância Magnética , Criança , Humanos , Estudo de Prova de Conceito
14.
Rofo ; 193(3): 276-288, 2021 Mar.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-33242898

RESUMO

PURPOSE: The DRG-ÖRG IRP (Deutsche Röntgengesellschaft-Österreichische Röntgengesellschaft international radiomics platform) represents a web-/cloud-based radiomics platform based on a public-private partnership. It offers the possibility of data sharing, annotation, validation and certification in the field of artificial intelligence, radiomics analysis, and integrated diagnostics. In a first proof-of-concept study, automated myocardial segmentation and automated myocardial late gadolinum enhancement (LGE) detection using radiomic image features will be evaluated for myocarditis data sets. MATERIALS AND METHODS: The DRG-ÖRP IRP can be used to create quality-assured, structured image data in combination with clinical data and subsequent integrated data analysis and is characterized by the following performance criteria: Possibility of using multicentric networked data, automatically calculated quality parameters, processing of annotation tasks, contour recognition using conventional and artificial intelligence methods and the possibility of targeted integration of algorithms. In a first study, a neural network pre-trained using cardiac CINE data sets was evaluated for segmentation of PSIR data sets. In a second step, radiomic features were applied for segmental detection of LGE of the same data sets, which were provided multicenter via the IRP. RESULTS: First results show the advantages (data transparency, reliability, broad involvement of all members, continuous evolution as well as validation and certification) of this platform-based approach. In the proof-of-concept study, the neural network demonstrated a Dice coefficient of 0.813 compared to the expert's segmentation of the myocardium. In the segment-based myocardial LGE detection, the AUC was 0.73 and 0.79 after exclusion of segments with uncertain annotation.The evaluation and provision of the data takes place at the IRP, taking into account the FAT (fairness, accountability, transparency) and FAIR (findable, accessible, interoperable, reusable) criteria. CONCLUSION: It could be shown that the DRG-ÖRP IRP can be used as a crystallization point for the generation of further individual and joint projects. The execution of quantitative analyses with artificial intelligence methods is greatly facilitated by the platform approach of the DRG-ÖRP IRP, since pre-trained neural networks can be integrated and scientific groups can be networked.In a first proof-of-concept study on automated segmentation of the myocardium and automated myocardial LGE detection, these advantages were successfully applied.Our study shows that with the DRG-ÖRP IRP, strategic goals can be implemented in an interdisciplinary way, that concrete proof-of-concept examples can be demonstrated, and that a large number of individual and joint projects can be realized in a participatory way involving all groups. KEY POINTS: · The DRG-ÖRG IRP is a web/cloud-based radiomics platform based on a public-private partnership.. · The DRG-ÖRG IRP can be used for the creation of quality-assured, structured image data in combination with clinical data and subsequent integrated data analysis.. · First results show the applicability of left ventricular myocardial segmentation using a neural network and segment-based LGE detection using radiomic image features.. · The DRG-ÖRG IRP offers the possibility of integrating pre-trained neural networks and networking of scientific groups.. CITATION FORMAT: · Overhoff D, Kohlmann P, Frydrychowicz A et al. The International Radiomics Platform - An Initiative of the German and Austrian Radiological Societies. Fortschr Röntgenstr 2021; 193: 276 - 287.


Assuntos
Coração , Processamento de Imagem Assistida por Computador , Radiologia , Inteligência Artificial , Áustria , Computação em Nuvem , Alemanha , Coração/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Acesso à Internet , Radiologia/métodos , Reprodutibilidade dos Testes , Sociedades
15.
J Clin Med ; 9(12)2020 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-33260461

RESUMO

Cardiac magnetic resonance (CMR)-derived left ventricular (LV) global longitudinal strain (GLS) provides incremental prognostic information on various cardiovascular diseases but has not yet been investigated comprehensively in patients with Takotsubo syndrome (TS). This study evaluated the prognostic value of feature tracking (FT) GLS, tissue tracking (TT) GLS, and fast manual long axis strain (LAS) in 147 patients with TS, who underwent CMR at a median of 2 days after admission. Long-term mortality was assessed 3 years after the acute event. In contrast to LV ejection fraction and tissue characteristics, impaired FT-GLS, TT-GLS and fast manual LAS were associated with adverse outcome. The best cutoff points for the prediction of long-term mortality were similar with all three approaches: FT-GLS -11.28%, TT-GLS -11.45%, and fast manual LAS -10.86%. Long-term mortality rates were significantly higher in patients with FT-GLS > -11.28% (25.0% versus 9.8%; p = 0.029), TT-GLS > -11.45% (20.0% versus 5.4%; p = 0.016), and LAS > -10.86% (23.3% versus 6.6%; p = 0.014). However, in multivariable analysis, diabetes mellitus (p = 0.001), atrial fibrillation (p = 0.001), malignancy (p = 0.006), and physical triggers (p = 0.006) outperformed measures of myocardial strain and emerged as the strongest, independent predictors of long-term mortality in TS. In conclusion, CMR-based longitudinal strain provides valuable prognostic information in patients with TS, regardless of the utilized technique of assessment. Long-term mortality, however, is mainly determined by comorbidities.

16.
J Cardiovasc Magn Reson ; 22(1): 59, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32772927

RESUMO

BACKGROUND: Anatomically pre-shaped sinus prostheses (SP) were developed to mimic the aortic sinus with the goal to preserve near physiological hemodynamic conditions after valve-sparing aortic root replacement. Although SP have shown more physiological flow patterns, a comparison to straight tube prosthesis and the analysis of derived quantitative parameters is lacking. Hence, this study sought to analyze differences in aortic wall shear stress (WSS) between anatomically pre-shaped SP, conventional straight tube prostheses (TP), and age-matched healthy subjects) using time-resolved 3-dimensional flow cardiovascular magnetic resonance (4D Flow CMR). Moreover, the WSS gradient was introduced and analyzed regarding its sensitivity to detect changes in hemodynamics and its dependency on the expression of secondary flow patterns. METHODS: Twelve patients with SP (12 male, 62 ± 9yr), eight patients with TP (6 male, 59 ± 9yr), and twelve healthy subjects (2 male, 55 ± 6yr) were examined at 3 T with a 4D Flow CMR sequence in this case control study. Six analysis planes were placed in the thoracic aorta at reproducible landmarks. The following WSS parameters were recorded: WSSavg (spatially averaged over the contour at peak systole), max. WSSseg (maximum segmental WSS), min. WSSseg (minimum segmental WSS) and the WSS Gradient, calculated as max. WSSseg - min. WSSseg. Kruskal-Wallis- and Mann-Whitney-U-Test were used for statistical comparison of groups. Occurrence and expression of secondary flow patterns were evaluated and correlated to WSS values using Spearman's correlation coefficient. RESULTS: In the planes bordering the prosthesis all WSS values were significantly lower in the SP compared to the TP, approaching the physiological optimum of the healthy subjects. The WSS gradient showed significantly different values in the four proximally localized contours when comparing both prostheses with healthy subjects. Strong correlations between an elevated WSS gradient and secondary flow patterns were found in the ascending aorta and the aortic arch. CONCLUSION: Overall, the SP has a positive impact on WSS, most pronounced at the site and adjacent to the prosthesis. The WSS gradient differed most obviously and the correlation of the WSS gradient with the occurrence of secondary flow patterns provides further evidence for linking disturbed flow, which was markedly increased in patients compared to healthy sub jects, to degenerative remodeling of the vascular wall.


Assuntos
Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Valva Aórtica/diagnóstico por imagem , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Hemodinâmica , Imageamento por Ressonância Magnética , Imagem de Perfusão/métodos , Desenho de Prótese , Adulto , Idoso , Aorta Torácica/fisiopatologia , Valva Aórtica/fisiopatologia , Técnicas de Imagem de Sincronização Cardíaca , Estudos de Casos e Controles , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fluxo Sanguíneo Regional , Estresse Mecânico , Resultado do Tratamento
17.
Urol Oncol ; 38(7): 636.e7-636.e12, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32113858

RESUMO

INTRODUCTION: Multiparametric magnetic resonance imaging (mpMRI)/ultrasound fusion-guided biopsy, in short "targeted biopsy (TB)", is becoming more attractive as it improves the detection of clinically significant prostate cancer (CaP). The accuracy of fusion-guided biopsies is limited due to false positive radiological findings as well as to histological evidence for cancer in radiologically inconspicuous regions of the prostate. We aimed to analyze histomorphological findings on mpMRI lesions highly suspicious for CaP classified as PI-RADS 4 or PI-RADS 5 (Prostate Imaging - Recording and Data System) but cancer-negative in the biopsy of this region of interest (ROI), and to compare them with findings in radiologically inconspicuous regions. MATERIALS AND METHODS: We re-evaluated prostate biopsies from 57 patients who underwent TB in combination with systematic standard biopsy (SB) from June 2017 to July 2018 at the University Hospital Schleswig Holstein Campus Luebeck. Out of 143 ROIs, 34 PI-RADS 4/5 cancer-negative lesions were identified and subjected to comprehensive histomorphological reevaluation. Contralateral cancer-negative SBs were used as control. Chi-square test was used for statistical analysis. RESULTS: The frequency of histomorphological alterations including stromal, glandular, vascular, and inflammatory alterations were 97% and 79.2% in prostatic tissues from cancer-negative TBs and SBs, respectively. Stromal, glandular, and inflammatory alterations were present in the majority of biopsies from both TBs and SBs. Statistical analysis revealed no significant difference between TBs and SBs with regard to stromal, glandular, and inflammatory alterations. However, vascular abnormalities were exclusively detected in TBs (18.2%). CONCLUSION: The frequency of histomorphological alterations is slightly higher in prostate tissues from TBs compared to SB. Only vascular alterations seem to be distinct for TBs. However, it has to be assumed that additional factors influence the false-negative rate of mpMRI/ultrasound fusion-guided TB.


Assuntos
Biópsia Guiada por Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Reações Falso-Positivas , Humanos , Masculino
18.
J Endocrinol ; 244(1): 95-110, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31585441

RESUMO

The AT1 receptor blocker telmisartan (TEL) prevents diet-induced obesity. Hypothalamic lipid metabolism is functionally important for energy homeostasis, as a surplus of lipids induces an inflammatory response in the hypothalamus, thus promoting the development of central leptin resistance. However, it is unclear as to whether TEL treatment affects the lipid status in the hypothalamus. C57BL/6N mice were fed with chow (CONchow) or high-fat diet (CONHFD). HFD-fed mice were gavaged with TEL (8 mg/kg/day, 12 weeks, TELHFD). Mice were phenotyped regarding weight gain, energy homeostasis, and glucose control. Hypothalamic lipid droplets were analyzed by fluorescence microscopy. Lipidomics were assessed by performing liquid chromatography-mass spectrometry in plasma and hypothalami. Adipokines were investigated using immunosorbent assays. Glial fibrillary acidic protein (GFAP) was determined by Western blotting and immunohistochemical imaging. We found that body weight, energy homeostasis, and glucose control of TEL-treated mice remained normal while CONHFD became obese. Hypothalamic ceramide and triglyceride levels as well as alkyne oleate distribution were normalized in TELHFD. The lipid droplet signal in the tanycyte layer was higher in CONHFD than in CONchow and returned to normal under TELHFD conditions. High hypothalamic levels of GFAP protein indicate astrogliosis of CONHFD mice while normalized GFAP, TNFα, and IL1α levels of TELHFD mice suggest that TEL prevents hypothalamic inflammation. In conclusion, TEL has anti-obese efficacy and prevented lipid accumulation and lipotoxicity, which is accompanied by an anti-inflammatory effect in the murine hypothalamus. Our findings support the notion that a brain-related mechanism is involved in TEL-induced weight loss.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/administração & dosagem , Gotículas Lipídicas/efeitos dos fármacos , Obesidade/prevenção & controle , Telmisartan/administração & dosagem , Aumento de Peso/efeitos dos fármacos , Ração Animal , Animais , Dieta Hiperlipídica/efeitos adversos , Hipotálamo/metabolismo , Leptina/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia
19.
Cardiovasc Intervent Radiol ; 43(2): 331-338, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31578634

RESUMO

PURPOSE: To illustrate the potential of magnetic particle imaging (MPI) for stent lumen imaging in comparison with clinical computed tomography (CT) and magnetic resonance imaging (MRI). MATERIALS AND METHODS: Imaging of eight tracer-filled, stented vessel phantoms and a tracer-filled, non-stented reference phantom for each diameter was performed on a preclinical MPI scanner: eight commercially available coronary stents of different dimensions (diameter: 3-4 mm; length: 11-38 mm) and materials (stainless steel, platinum-chromium) were implanted into silicone vessel phantoms. For comparison, all vessel phantoms were also visualized by MRI and CT. Two radiologists assessed the images regarding stent-induced artifacts using a 5-point grading scale. RESULTS: The visualization of all stented vessel phantoms was achieved without stent-induced artifacts with MPI. In contrast, MRI and CT images revealed multiform stent-induced artifacts. CONCLUSION: Given its clinical introduction, MPI has the potential to overcome the disadvantages of MRI and CT concerning the visualization of the stent lumen.


Assuntos
Artefatos , Processamento de Imagem Assistida por Computador/métodos , Nanopartículas de Magnetita , Imagens de Fantasmas , Stents , Tomografia/métodos , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos
20.
J Thorac Cardiovasc Surg ; 159(3): 798-810.e1, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31078313

RESUMO

OBJECTIVE: The aim of this study was to compare aortic flow patterns in patients after David valve-sparing aortic root replacement with physiologically shaped sinus prostheses or conventional tube grafts in healthy volunteers. METHODS: Twelve patients with sinus prostheses (55 ± 15 years), 6 patients with tube grafts (58 ± 12 years), 12 age-matched, healthy volunteers (55 ± 6 years), and 6 young, healthy volunteers (25 ± 3 years) were examined with time-resolved 3-dimensional magnetic resonance phase contrast imaging (4D Flow MRI). Primary and secondary helical, as well as vortical flow patterns, were evaluated. Aortic arch anatomy as a flow influencing factor was determined. RESULTS: Compared with volunteers, both sinus prostheses and tube grafts developed more than 4 times as many secondary flow patterns in the ascending aorta (sinus prostheses n = 1.6 ± 0.8; tube grafts n = 1.3 ± 0.6; age-matched, healthy volunteers n = 0.3 ± 0.5; young, healthy volunteers n = 0; P ≤ .012) associated with a kinking of the prosthesis itself or at its distal anastomosis. As opposed to round aortic arches in volunteers (n = 16/18), cubic or gothic-shaped arches predominated in patients (n = 16/18, P < .001). In all but 3 volunteers, 2 counter-rotating helices were confirmed in the ascending aorta and were defined as a primary flow pattern. This primary flow pattern did not develop in patients who underwent valve-sparing aortic root replacement. CONCLUSIONS: In patients after valve-sparing aortic root replacement, there was an increased number of secondary flow patterns in the ascending aorta. This seems to be related to surgically altered aortic geometry with kinking. Because flow alterations are known to affect wall shear stress, there seems to be an increased risk for vessel wall remodeling. Compared with previous 4D Flow MRI studies, primary flow patterns in the ascending aorta in healthy subjects were confirmed to be more complex. This underlines the importance of thorough examination of 4D Flow MRI data.


Assuntos
Aorta/cirurgia , Aneurisma Aórtico/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Hemodinâmica , Imageamento Tridimensional , Angiografia por Ressonância Magnética , Imagem de Perfusão/métodos , Adulto , Idoso , Aorta/diagnóstico por imagem , Aorta/fisiopatologia , Aneurisma Aórtico/diagnóstico por imagem , Aneurisma Aórtico/fisiopatologia , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/fisiopatologia , Velocidade do Fluxo Sanguíneo , Implante de Prótese Vascular/efeitos adversos , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Modelagem Computacional Específica para o Paciente , Projetos Piloto , Valor Preditivo dos Testes , Desenho de Prótese , Falha de Prótese , Fluxo Sanguíneo Regional , Fatores de Tempo , Resultado do Tratamento
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