Jonas Stroeder
Saarland University
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Publication
Featured researches published by Jonas Stroeder.
PLOS ONE | 2016
Jochen Fleckenstein; Michael Jelden; Stephanie Kremp; Philippe Jagoda; Jonas Stroeder; Fadi Khreish; Samer Ezziddin; Arno Buecker; Christian Rübe; Guenther Schneider
Objective The study was designed to evaluate diffusion-weighted magnetic resonance imaging (DWI) vs. PET-CT of the thorax in the determination of gross tumor volume (GTV) in radiotherapy planning of non-small-cell lung cancer (NSCLC). Materials and Methods Eligible patients with NSCLC who were supposed to receive definitive radio(chemo)therapy were prospectively recruited. For MRI, a respiratory gated T2-weighted sequence in axial orientation and non-gated DWI (b = 0, 800, 1,400 and apparent diffusion coefficient map [ADC]) were acquired on a 1.5 Tesla scanner. Primary tumors were delineated on FDG-PET/CT (stGTV) and DWI images (dwGTV). The definition of stGTV was based on the CT and visually adapted to the FDG-PET component if indicated (e.g., in atelectasis). For DWI, dwGTV was visually determined and adjusted for anatomical plausibility on T2w sequences. Beside a statistical comparison of stGTV and dwGTB, spatial agreement was determined with the “Hausdorff-Distance” (HD) and the “Dice Similarity Coefficient” (DSC). Results Fifteen patients (one patient with two synchronous NSCLC) were evaluated. For 16 primary tumors with UICC stages I (n = 4), II (n = 3), IIIA (n = 2) and IIIB (n = 7) mean values for dwGTV were significantly larger than those of stGTV (76.6 ± 84.5 ml vs. 66.6 ± 75.2 ml, p<0.01). The correlation of stGTV and dwGTV was highly significant (r = 0.995, p<0.001). Yet, some considerable volume deviations between these two methods were observed (median 27.5%, range 0.4–52.1%). An acceptable agreement between dwGTV and stGTV regarding the spatial extent of primary tumors was found (average HD: 2.25 ± 0.7 mm; DC 0.68 ± 0.09). Conclusion The overall level of agreement between PET-CT and MRI based GTV definition is acceptable. Tumor volumes may differ considerably in single cases. DWI-derived GTVs are significantly, yet modestly, larger than their PET-CT based counterparts. Prospective studies to assess the safety and efficacy of DWI-based radiotherapy planning in NSCLC are warranted.
American Journal of Roentgenology | 2016
Paul Raczeck; Peter Minko; Stefan Graeber; Peter Fries; Roland Seidel; Arno Buecker; Jonas Stroeder
OBJECTIVE The purpose of this study was to prospectively compare the effect of inspiration and resting expiratory position on contrast enhancement in pulmonary CT angiography (CTA) in a randomized clinical trial. SUBJECTS AND METHODS In accordance with a power analysis performed before the study, we included 28 consecutive patients referred for evaluation of suspected pulmonary embolism in this prospective study. Patients were randomly assigned to perform either inspiration (n = 14; six men, eight women; mean age [SD], 38.1 ± 9.8 years) or resting expiratory position (n = 14; six men, eight women; mean age: 42.1 ± 9.2 years). All patients were scanned in a standardized supine position and scanning parameters were kept constant. Contrast medium was injected automatically with bolus tracking. Objective pulmonary vessel attenuation was quantified with digital measurement. Results were analyzed by using the unpaired t test and chi-square test. RESULTS Patients in the resting expiratory position showed significantly higher contrast attenuation than those who performed inspiration (302.9 ± 11.9 HU vs 221.5 ± 20.9 HU; p < 0.01). There were no significant differences in applied total volume of contrast agent (76.8 ± 1.9 mL vs 75.7 ± 1.6 mL; p = 0.6765), total volume including normal saline bolus (116.8 mL ± 2.8 mL vs 121.8 mL ± 2.3 mL; p = 0.1724) or flow rate (3.1 mL/s ± 0.1 mL/s vs 3.2 mL/s ± 0.1 mL/s). CONCLUSION Pulmonary CTA should be performed in the resting expiratory position, and patients should be instructed to avoid inspiration to achieve the highest possible attenuation in the pulmonary arteries.
Journal of Cardiothoracic and Vascular Anesthesia | 2018
Hagen Bomberg; Jonas Stroeder; Kathrin Karrenbauer; Heinrich V. Groesdonk; Stefan Wagenpfeil; Matthias Klingele; Arno Bücker; Hans-Joachim Schäfers; Peter Minko
OBJECTIVE The aim of this study was to develop clinical preoperative, intraoperative, and postoperative scores for early identification of patients who are at risk of nonocclusive mesenteric ischemia (NOMI). DESIGN A retrospective analysis. SETTING Single center. PARTICIPANTS From January 2008 to December 2014, all patients from the Department of Thoracic and Cardiovascular Surgery were included on the basis of the hospital database. INTERVENTIONS All mesenteric angiographically identified NOMI patients were compared with non-NOMI patients. MEASUREMENTS AND MAIN RESULTS The study population of 8,748 patients was randomized into a cohort for developing the scores (non-NOMI 4,214 and NOMI 235) and a cohort for control (non-NOMI 4,082 and NOMI 217). Risk factors were identified using forward and backward Wald test and were included in the predictive scores for the occurrence of NOMI. C statistic showed that the scores had a high discrimination for the prediction of NOMI preoperatively (C statistic 0.79; p < 0.001), intraoperatively (C statistic 0.68; p < 0.001), and postoperatively (C statistic 0.85; p < 0.001). A combination of the preoperative, intraoperative, and postoperative risk scores demonstrated the highest discrimination (C statistic 0.87; p < 0.001). The combined score included the following risk factors: renal insufficiency (preoperative); use of cardiopulmonary bypass and intra-aortic balloon pump support (intraoperative); and reexploration for bleeding, renal replacement therapy, and packed red blood cells ≥ 4 units (postoperative). The results were similar in the control group. CONCLUSIONS These scores could be useful to identify patients at risk for NOMI and promote a rapid diagnosis and therapy.
PLOS ONE | 2017
Jonas Stroeder; Matthias Klingele; Hagen Bomberg; Stefan Wagenpfeil; Arno Buecker; Hans-Joachim Schaefers; Marcus Katoh; Peter Minko
Purpose To evaluate the value of preoperatively assessed fibroblast growth factor 23 (FGF-23) levels and to correlate FGF-23 with angiographic findings in non-occlusive mesenteric (NOMI) ischemia using a standardized scoring system. Materials and methods Between 2/2011 and 3/2012 a total of 865 patients (median age: 67 years) underwent cardiovascular surgery during this ethics committee approved, prospective study. 65 of these patients had clinical suspicion of NOMI and consequently underwent catheter angiography of the superior mesenteric artery. Images were assessed using a standardized reporting system (Homburg-NOMI-Score). These data were correlated to following preoperative parameters of kidney function: cystatin C, creatinine, FGF-23 and estimated glomerular filtration rate (eGFR), and outcome data (death, acute renal failure) using linear and logistic regressions, as well as nonparametric tests. Results Significant correlations were found between FGF-23 and the angiographic appearance of NOMI (p = 0.03). Linear regression analysis showed no significant correlation to the severity of NOMI with creatinine (p = 0.273), cystatin C (p = 0.484), cystatin C eGFR (p = 0.914) and creatinine eGFR (p = 0.380). Logistic regression revealed a significant correlation between death and the Homburg-NOMI-Score (p<0.001), but not between development of NOMI and acute renal failure (p = 0.122). The ROC Analysis yielded an area under the curve of 0.695 (95% CI: 0.627–0.763) with a sensitivity of 0.672 and specificity of 0.658. Conclusions FGF-23 significantly correlates with the severity of NOMI, which is in contrast to other renal function parameters. The applied scoring system allows to predict mortality in NOMI patients.
BioMed Research International | 2017
Andreas Müller; Katrin Hochrath; Jonas Stroeder; Kanishka Hittatiya; Günther Schneider; Frank Lammert; Arno Buecker; Peter Fries
Recently, clinical studies demonstrated that magnetic resonance relaxometry with determination of relaxation times T1 and T2⁎ may aid in staging and management of liver fibrosis in patients suffering from viral hepatitis and steatohepatitis. In the present study we investigated T1 and T2⁎ in different models of liver fibrosis to compare alternate pathophysiologies in their effects on relaxation times and to further develop noninvasive quantification methods of liver fibrosis. MRI was performed with a fast spin echo sequence for measurement of T1 and a multigradient echo sequence for determination of T2⁎. Toxic liver fibrosis was induced by injections of carbon tetrachloride (1.4 mL CCl4 per kg bodyweight and week, for 3 or 6 weeks) in BALB/cJ mice. Chronic sclerosing cholangitis was mimicked using the ATP-binding cassette transporter B4 knockout (Abcb4 −/−) mouse model. Untreated BALB/cJ mice served as controls. To assess hepatic fibrosis, we ascertained collagen contents and fibrosis scores after Sirius red staining. T1 and T2⁎ correlate differently to disease severity and etiology of liver fibrosis. T2⁎ shows significant decrease correlating with fibrosis in CCl4 treated animals, while demonstrating significant increase with disease severity in Abcb4 −/− mice. Measurements of T1 and T2⁎ may therefore facilitate discrimination between different stages and causes of liver fibrosis.
Rofo-fortschritte Auf Dem Gebiet Der Rontgenstrahlen Und Der Bildgebenden Verfahren | 2012
Peter Minko; H Groesdonk; Jonas Stroeder; Miodek J; Graeber S; A Bücker; Schäfers Hj; Marcus Katoh
CardioVascular and Interventional Radiology | 2014
Peter Minko; Jonas Stroeder; Heinrich V. Groesdonk; Stefan Graeber; Matthias Klingele; Arno Buecker; Hans Joachim Schäfers; Marcus Katoh
Journal of Translational Medicine | 2016
Mathias Hohl; Dominik Linz; Peter Fries; Andreas Müller; Jonas Stroeder; Daniel J. Urban; Thimoteus Speer; Jürgen Geisel; Björn Hummel; Ulrich Laufs; Stephan H. Schirmer; Michael Böhm; Felix Mahfoud
Rofo-fortschritte Auf Dem Gebiet Der Rontgenstrahlen Und Der Bildgebenden Verfahren | 2015
Peter Fries; Jonas Stroeder; Andreas Müller; F Mafoud; M Hohl; D Linz; A Maßmann; R Seidel; Günther Schneider; A Bücker
Radiologia Medica | 2015
Guenther Schneider; Thorsten Probst; Miles A. Kirchin; Jonas Stroeder; Peter Fries; Arno Buecker