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101. Characteristics of carotid atherosclerotic plaques of chronic lipid apheresis patients as assessed by In Vivo High-Resolution CMR - a comparative analysis

Author

Grimm Jochen M, Nikolaou Konstantin, Schindler Andreas, Hettich Reinhard, Heigl Franz, Cyran Clemens C, Schwarz Florian, Klingel Reinhard, Karpinska Anna, Yuan Chun, Dichgans Martin, Reiser Maximilian F, and Saam Tobias

Subjects
Atherosclerosis, Lipid apheresis, Cardiovascular MR, Plaque imaging, Stroke, Cardiovascular disease, Diseases of the circulatory (Cardiovascular) system, RC666-701
Abstract

Abstract Background Components of carotid atherosclerotic plaques can reliably be identified and quantified using high resolution in vivo 3-Tesla CMR. It is suspected that lipid apheresis therapy in addition to lowering serum lipid levels also has an influence on development and progression of atherosclerotic plaques. The purpose of this study was to evaluate the influence of chronic lipid apheresis (LA) on the composition of atherosclerotic carotid plaques. Methods 32 arteries of 16 patients during chronic LA-therapy with carotid plaques and stenosis of 1–80% were matched according to degree of stenosis with 32 patients, who had recently suffered an ischemic stroke. Of these patients only the asymptomatic carotid artery was analyzed. All patients underwent black-blood 3 T CMR of the carotids using parallel imaging and dedicated surface coils. Cardiovascular risk factors were recorded. Morphology and composition of carotid plaques were evaluated. For statistical evaluation Fisher’s Exact and unpaired t-test were used. A p-value Results Patients in the LA-group were younger (63.5 vs. 73.9. years, p2, p Conclusion Results of this study suggest that, despite a severer risk profile for cardiovascular complications in LA-patients, chronic LA is associated with significantly lower lipid content in carotid plaques compared to plaques of patients without LA with similar degrees of stenosis, which is characteristic of clinically stable plaques.

Published
2012
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103. Age determination of vessel wall hematoma in spontaneous cervical artery dissection: A multi-sequence 3T Cardiovascular Magnetic resonance study

Author

Habs Maximilian, Pfefferkorn Thomas, Cyran Clemens C, Grimm Jochen, Rominger Axel, Hacker Marcus, Opherk Christian, Reiser Maximilian F, Nikolaou Konstantin, and Saam Tobias

Subjects
CMR, internal carotid artery dissection, vertebral artery dissection, hematoma, stroke, Diseases of the circulatory (Cardiovascular) system, RC666-701
Abstract

Abstract Background Previously proposed classifications for carotid plaque and cerebral parenchymal hemorrhages are used to estimate the age of hematoma according to its signal intensities on T1w and T2w MR images. Using these classifications, we systematically investigated the value of cardiovascular magnetic resonance (CMR) in determining the age of vessel wall hematoma (VWH) in patients with spontaneous cervical artery dissection (sCAD). Methods 35 consecutive patients (mean age 43.6 ± 9.8 years) with sCAD received a cervical multi-sequence 3T CMR with fat-saturated black-blood T1w-, T2w- and TOF images. Age of sCAD was defined as time between onset of symptoms (stroke, TIA or Horner's syndrome) and the CMR scan. VWH were categorized into hyperacute, acute, early subacute, late subacute and chronic based on their signal intensities on T1w- and T2w images. Results The mean age of sCAD was 2.0, 5.8, 15.7 and 58.7 days in patients with acute, early subacute, late subacute and chronic VWH as classified by CMR (p < 0.001 for trend). Agreement was moderate between VWH types in our study and the previously proposed time scheme of signal evolution for cerebral hemorrhage, Cohen's kappa 0.43 (p < 0.001). There was a strong agreement of CMR VWH classification compared to the time scheme which was proposed for carotid intraplaque hematomas with Cohen's kappa of 0.74 (p < 0.001). Conclusions Signal intensities of VWH in sCAD vary over time and multi-sequence CMR can help to determine the age of an arterial dissection. Furthermore, findings of this study suggest that the time course of carotid hematomas differs from that of cerebral hematomas.

Published
2011
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104. Assessment of right ventricular sympathetic dysfunction in patients with arrhythmogenic right ventricular cardiomyopathy: An 123I-metaiodobenzylguanidine SPECT/CT study

Author

Todica, Andrei, primary, Siebermair, Johannes, additional, Schiller, Julia, additional, Zacherl, Mathias J., additional, Fendler, Wolfgang P., additional, Massberg, Steffen, additional, Bartenstein, Peter, additional, Cyran, Clemens C., additional, Kääb, Stefan, additional, Hacker, Marcus, additional, Wakili, Reza, additional, and Lehner, Sebastian, additional

Published
2018
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105. Impact of 68Ga-PSMA PET/CT on the Radiotherapeutic Approach to Prostate Cancer in Comparison to CT: A Retrospective Analysis

Author

Schmidt-Hegemann, Nina-Sophie, primary, Eze, Chukwuka, additional, Li, Minglun, additional, Rogowski, Paul, additional, Schaefer, Christian, additional, Stief, Christian, additional, Buchner, Alexander, additional, Zamboglou, Constantinos, additional, Fendler, Wolfgang Peter, additional, Ganswindt, Ute, additional, Cyran, Clemens, additional, Bartenstein, Peter, additional, Belka, Claus, additional, and Ilhan, Harun, additional

Published
2018
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106. High resolution carotid black-blood 3T MR with parallel imaging and dedicated 4-channel surface coils

Author

Frey Ute, Clevert Dirk A, Dietrich Olaf, Meimarakis Georgios, Bochmann Katja, Cyran Clemens C, Raya Jose G, Saam Tobias, Yuan Chun, Hatsukami Thomas S, Werf Abe, Reiser Maximilian F, and Nikolaou Konstantin

Subjects
Diseases of the circulatory (Cardiovascular) system, RC666-701
Abstract

Abstract Background Most of the carotid plaque MR studies have been performed using black-blood protocols at 1.5 T without parallel imaging techniques. The purpose of this study was to evaluate a multi-sequence, black-blood MR protocol using parallel imaging and a dedicated 4-channel surface coil for vessel wall imaging of the carotid arteries at 3 T. Materials and methods 14 healthy volunteers and 14 patients with intimal thickening as proven by duplex ultrasound had their carotid arteries imaged at 3 T using a multi-sequence protocol (time-of-flight MR angiography, pre-contrast T1w-, PDw- and T2w sequences in the volunteers, additional post-contrast T1w- and dynamic contrast enhanced sequences in patients). To assess intrascan reproducibility, 10 volunteers were scanned twice within 2 weeks. Results Intrascan reproducibility for quantitative measurements of lumen, wall and outer wall areas was excellent with Intraclass Correlation Coefficients >0.98 and measurement errors of 1.5%, 4.5% and 1.9%, respectively. Patients had larger wall areas than volunteers in both common carotid and internal carotid arteries and smaller lumen areas in internal carotid arteries (p < 0.001). Positive correlations were found between wall area and cardiovascular risk factors such as age, hypertension, coronary heart disease and hypercholesterolemia (Spearman's r = 0.45-0.76, p < 0.05). No significant correlations were found between wall area and body mass index, gender, diabetes or a family history of cardiovascular disease. Conclusion The findings of this study indicate that high resolution carotid black-blood 3 T MR with parallel imaging is a fast, reproducible and robust method to assess carotid atherosclerotic plaque in vivo and this method is ready to be used in clinical practice.

Published
2009
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107. Simpson Grade Revisited – Intraoperative Estimation of the Extent of Resection in Meningiomas Versus Postoperative Somatostatin Receptor Positron Emission Tomography/Computed Tomography and Magnetic Resonance Imaging.

Author

Ueberschaer, Moritz, Vettermann, Franziska Jill, Forbrig, Robert, Unterrainer, Marcus, Siller, Sebastian, Biczok, Anna-Maria, Thorsteinsdottir, Jun, Cyran, Clemens C, Bartenstein, Peter, Tonn, Jörg-Christian, Albert, Nathalie Lisa, and Schichor, Christian

Published
2021
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108. Integrin-targeted quantitative optoacoustic imaging with MRI correlation for monitoring a BRAF/MEK inhibitor combination therapy in a murine model of human melanoma

Author

Kazmierczak, Philipp M., primary, Burton, Neal C., additional, Keinrath, Georg, additional, Hirner-Eppeneder, Heidrun, additional, Schneider, Moritz J., additional, Eschbach, Ralf S., additional, Heimer, Maurice, additional, Solyanik, Olga, additional, Todica, Andrei, additional, Reiser, Maximilian F., additional, Ricke, Jens, additional, and Cyran, Clemens C., additional

Published
2018
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110. 18F–FDG-PET/CT and diffusion-weighted MRI for monitoring a BRAF and CDK 4/6 inhibitor combination therapy in a murine model of human melanoma

Author

Eschbach, Ralf S., primary, Kazmierczak, Philipp M., additional, Heimer, Maurice M., additional, Todica, Andrei, additional, Hirner-Eppeneder, Heidrun, additional, Schneider, Moritz J., additional, Keinrath, Georg, additional, Solyanik, Olga, additional, Olivier, Jessica, additional, Kunz, Wolfgang G., additional, Reiser, Maximilian F., additional, Bartenstein, Peter, additional, Ricke, Jens, additional, and Cyran, Clemens C., additional

Published
2018
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112. The added value of 68Ga-DOTA-TATE-PET to contrast-enhanced CT for primary site detection in CUP of neuroendocrine origin.

Author

Kazmierczak, Philipp, Rominger, Axel, Wenter, Vera, Spitzweg, Christine, Auernhammer, Christoph, Angele, Martin, Rist, Carsten, Cyran, Clemens, Kazmierczak, Philipp M, Angele, Martin K, and Cyran, Clemens C

Subjects
NEUROENDOCRINE tumors, COMPUTED tomography, CANCER patients, POSITRON emission tomography, TUMOR diagnosis, DIAGNOSIS, ORGANOMETALLIC compounds, RADIOPHARMACEUTICALS, CANCER of unknown primary origin, RESEARCH bias, RETROSPECTIVE studies
Abstract

Objectives: To quantify the additional value of 68Ga-DOTA-TATE PET/CT in comparison with contrast-enhanced CT alone for primary tumour detection in neuroendocrine cancer of unknown primary (CUP-NET).Methods: In total, 38 consecutive patients (27 men, 11 women; mean age 62 years) with histologically proven CUP-NET who underwent a contrast-enhanced 68Ga-DOTA-TATE PET/CT scan for primary tumour detection and staging between 2010 and 2014 were included in this IRB-approved retrospective study. Two blinded readers independently analysed the contrast-enhanced CT and 68Ga-DOTA-TATE PET datasets separately and noted from which modality they suspected a primary tumour. Consensus was reached if the results were divergent. Postoperative histopathology (24 patients) and follow-up 68Ga-DOTA-TATE PET/CT imaging (14 patients) served as the reference standards and statistical measures of diagnostic accuracy were calculated accordingly.Results: The majority of confirmed primary tumours were located in the abdomen (ileum in 19 patients, pancreas in 12, lung in 2, small pelvis in 1). High interobserver agreement was noted regarding the suspected primary tumour site (Cohen's k 0.90, p < 0.001). 68Ga-DOTA-TATE PET demonstrated a significantly higher sensitivity (94 % vs. 63 %, p = 0.005) and a significantly higher accuracy (87 % vs. 68 %, p = 0.003) than contrast-enhanced CT.Conclusions: Ga-DOTA-TATE PET/CT compared with contrast-enhanced CT alone provides an improvement in sensitivity of 50 % and an improvement in accuracy of 30 % in primary tumour detection in CUP-NET.Key Points: • 68Ga-DOTA-TATE PET augments the sensitivity of contrast-enhanced CT by 50 % • 68Ga-DOTA-TATE PET augments the accuracy of contrast-enhanced CT by 30 % • Somatostatin receptor-targeted hybrid imaging optimizes primary tumour detection in CUP-NET. [ABSTRACT FROM AUTHOR]

Published
2017
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113. Improved Detection of Transosseous Meningiomas Using 68Ga-DOTATATE PET/CT Compared with Contrast-Enhanced MRI

Author

Kunz, Wolfgang G., primary, Jungblut, Lisa M., additional, Kazmierczak, Philipp M., additional, Vettermann, Franziska J., additional, Bollenbacher, Andreas, additional, Tonn, Jörg C., additional, Schichor, Christian, additional, Rominger, Axel, additional, Albert, Nathalie L., additional, Bartenstein, Peter, additional, Reiser, Maximilian F., additional, and Cyran, Clemens C., additional

Published
2017
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114. Contrast-Enhanced Ultrasound with VEGFR2-Targeted Microbubbles for Monitoring Regorafenib Therapy Effects in Experimental Colorectal Adenocarcinomas in Rats with DCE-MRI and Immunohistochemical Validation

Author

Eschbach, Ralf Stefan, primary, Clevert, Dirk-Andre, additional, Hirner-Eppeneder, Heidrun, additional, Ingrisch, Michael, additional, Moser, Matthias, additional, Schuster, Jessica, additional, Tadros, Dina, additional, Schneider, Moritz, additional, Kazmierczak, Philipp Maximilian, additional, Reiser, Maximilian, additional, and Cyran, Clemens C., additional

Published
2017
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115. 68Ga-TRAP-(RGD)3 Hybrid Imaging for the In Vivo Monitoring of αvß3-Integrin Expression as Biomarker of Anti-Angiogenic Therapy Effects in Experimental Breast Cancer

Author

Kazmierczak, Philipp M., primary, Todica, Andrei, additional, Gildehaus, Franz-Josef, additional, Hirner-Eppeneder, Heidrun, additional, Brendel, Matthias, additional, Eschbach, Ralf S., additional, Hellmann, Magdalena, additional, Nikolaou, Konstantin, additional, Reiser, Maximilian F., additional, Wester, Hans-Jürgen, additional, Kropf, Saskia, additional, Rominger, Axel, additional, and Cyran, Clemens C., additional

Published
2016
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116. αvß3-Integrin–Targeted Magnetic Resonance Imaging for the Assessment of Early Antiangiogenic Therapy Effects in Orthotopic Breast Cancer Xenografts

Author

Kazmierczak, Philipp Maximilian, primary, Schneider, Moritz, additional, Habereder, Thomas, additional, Hirner-Eppeneder, Heidrun, additional, Eschbach, Ralf S., additional, Moser, Matthias, additional, Reiser, Maximilian F., additional, Lauber, Kirsten, additional, Nikolaou, Konstantin, additional, and Cyran, Clemens C., additional

Published
2016
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123. Expansive arterial remodeling of the carotid arteries and its effect on atherosclerotic plaque composition and vulnerability: an in-vivo black-blood 3T CMR study in symptomatic stroke patients

Author

Saam, Tobias, primary, Habs, Maximilian, additional, Buchholz, Martin, additional, Schindler, Andreas, additional, Bayer-Karpinska, Anna, additional, Cyran, Clemens C., additional, Yuan, Chun, additional, Reiser, Maximilian, additional, and Helck, Andreas, additional

Published
2016
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124. The diagnostic value of [18F]FDG PET for the detection of chronic osteomyelitis and implant-associated infection

Author

Wenter, Vera, primary, Müller, Jan-Phillip, additional, Albert, Nathalie L., additional, Lehner, Sebastian, additional, Fendler, Wolfgang P., additional, Bartenstein, Peter, additional, Cyran, Clemens C., additional, Friederichs, Jan, additional, Militz, Matthias, additional, Hacker, Marcus, additional, and Hungerer, Sven, additional

Published
2015
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126. Non-invasive Monitoring of Sorafenib Effects on Tumor Growth and Angiogenesis by Dynamic Contrast-Enhanced CT Scans and Immunohistological Correlations

Author

Schwarz, E. Bettina F., Cyran, Clemens C., Paprottka, Philipp M., Sourbron, S., Von Einem, Jobst, Hinkel, Rabea, Dietrich, Oliver, Wintersberger, Bernd, Nikolaou, Konstantin, Reiser, Maximilian F., Jauch, Karl-Walter, and Bruns, Christiane J.

Subjects
ddc: 610, 610 Medical sciences, Medicine, urologic and male genital diseases, neoplasms, female genital diseases and pregnancy complications, digestive system diseases
Abstract

Introduction: Inhibiting tumor growth and angiogenesis, the oral multikinase inhibitor sorafenib is used for the treatment of advanced HCC and RCC. Despite promising clinical results, there is no sufficient data on its anti-angiogenic, anti-proliferative and pro-apoptotic effects concerning (pre-) clinical[for full text, please go to the a.m. URL], 128. Kongress der Deutschen Gesellschaft für Chirurgie

Published
2011

127. Monitoring Cell Death in Regorafenib-Treated Experimental Colon Carcinomas Using Annexin-Based Optical Fluorescence Imaging Validated by Perfusion MRI

Author

Kazmierczak, Philipp M., primary, Burian, Egon, additional, Eschbach, Ralf, additional, Hirner-Eppeneder, Heidrun, additional, Moser, Matthias, additional, Havla, Lukas, additional, Eisenblätter, Michel, additional, Reiser, Maximilian F., additional, Nikolaou, Konstantin, additional, and Cyran, Clemens C., additional

Published
2015
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128. The relevance of 18F-fluorodeoxyglucose positron emission tomography/computed tomography imaging in diagnosing prosthetic graft infections post cardiac and proximal thoracic aortic surgery

Author

Guenther, Sabina P.W., primary, Cyran, Clemens C., additional, Rominger, Axel, additional, Saam, Tobias, additional, Kazmierzcak, Philipp M., additional, Bagaev, Erik, additional, Pichlmaier, Maximilian, additional, Hagl, Christian, additional, and Khaladj, Nawid, additional

Published
2015
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129. Ex Vivo Perfusion-Simulation Measurements of Microbubbles as a Scattering Contrast Agent for Grating-Based X-Ray Dark-Field Imaging

Author

Velroyen, Astrid, primary, Bech, Martin, additional, Tapfer, Arne, additional, Yaroshenko, Andre, additional, Müller, Mark, additional, Paprottka, Philipp, additional, Ingrisch, Michael, additional, Cyran, Clemens C., additional, Auweter, Sigrid D., additional, Nikolaou, Konstantin, additional, Reiser, Maximilian F., additional, and Pfeiffer, Franz, additional

Published
2015
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131. Mesenchymal Stem Cell–Mediated, Tumor Stroma–Targeted Radioiodine Therapy of Metastatic Colon Cancer Using the Sodium Iodide Symporter as Theranostic Gene

Author

Knoop, Kerstin, primary, Schwenk, Nathalie, additional, Schmohl, Kathrin, additional, Müller, Andrea, additional, Zach, Christian, additional, Cyran, Clemens, additional, Carlsen, Janette, additional, Böning, Guido, additional, Bartenstein, Peter, additional, Göke, Burkhard, additional, Wagner, Ernst, additional, Nelson, Peter J., additional, and Spitzweg, Christine, additional

Published
2015
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132. DCE-MRI biomarkers for monitoring an anti-angiogenic triple combination therapy in experimental hypopharynx carcinoma xenografts with immunohistochemical validation

Author

Sterzik, Alexander, primary, Paprottka, Philipp M, additional, Zengel, Pamela, additional, Hirner, Heidrun, additional, Roßpunt, Svenja, additional, Eschbach, Ralf, additional, Moser, Matthias, additional, Havla, Lukas, additional, Ingrisch, Michael, additional, Mack, Brigitte, additional, Reiser, Maximilian F, additional, Nikolaou, Konstantin, additional, and Cyran, Clemens C, additional

Published
2015
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133. PET Response Criteria in Solid Tumors Predicts Progression-Free Survival and Time to Local or Distant Progression After Chemotherapy with Regional Hyperthermia for Soft-Tissue Sarcoma

Author

Fendler, Wolfgang P., primary, Lehmann, Mona, additional, Todica, Andrei, additional, Herrmann, Ken, additional, Knösel, Thomas, additional, Angele, Martin K., additional, Dürr, Hans Roland, additional, Rauch, Josefine, additional, Bartenstein, Peter, additional, Cyran, Clemens C., additional, Hacker, Marcus, additional, and Lindner, Lars H., additional

Published
2015
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134. Correlation of Perfusion MRI and 18F-FDG PET Imaging Biomarkers for Monitoring Regorafenib Therapy in Experimental Colon Carcinomas with Immunohistochemical Validation

Author

Eschbach, Ralf S., primary, Fendler, Wolfgang P., additional, Kazmierczak, Philipp M., additional, Hacker, Marcus, additional, Rominger, Axel, additional, Carlsen, Janette, additional, Hirner-Eppeneder, Heidrun, additional, Schuster, Jessica, additional, Moser, Matthias, additional, Havla, Lukas, additional, Schneider, Moritz J., additional, Ingrisch, Michael, additional, Spaeth, Lukas, additional, Reiser, Maximilian F., additional, Nikolaou, Konstantin, additional, and Cyran, Clemens C., additional

Published
2015
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136. Computed tomography angiography vs 3 T black-blood cardiovascular magnetic resonance for identification of symptomatic carotid plaques

Author

Grimm, Jochen M, primary, Schindler, Andreas, additional, Schwarz, Florian, additional, Cyran, Clemens C, additional, Bayer-Karpinska, Anna, additional, Freilinger, Tobias, additional, Yuan, Chun, additional, Linn, Jennifer, additional, Trelles, Miguel, additional, Reiser, Maximilian F, additional, Nikolaou, Konstantin, additional, and Saam, Tobias, additional

Published
2014
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137. High resolution carotid black-blood 3T MR with parallel imaging and dedicated 4-channel surface coils

Author

Saam, Tobias, Raya, Jose G, Cyran, Clemens C, Bochmann, Katja, Meimarakis, Georgios, Dietrich, Olaf, Clevert, Dirk A, Frey, Ute, Yuan, Chun, Hatsukami, Thomas S, Werf, Abe, Reiser, Maximilian F, and Nikolaou, Konstantin

Subjects
Medicine(all), Adult, Carotid Artery Diseases, Male, lcsh:Diseases of the circulatory (Cardiovascular) system, Ultrasonography, Doppler, Duplex, Carotid Artery, Common, Research, Reproducibility of Results, Equipment Design, Middle Aged, Severity of Illness Index, Young Adult, lcsh:RC666-701, Predictive Value of Tests, Case-Control Studies, Image Interpretation, Computer-Assisted, Humans, Female, Carotid Artery, Internal, Magnetic Resonance Angiography, Aged
Abstract

Background Most of the carotid plaque MR studies have been performed using black-blood protocols at 1.5 T without parallel imaging techniques. The purpose of this study was to evaluate a multi-sequence, black-blood MR protocol using parallel imaging and a dedicated 4-channel surface coil for vessel wall imaging of the carotid arteries at 3 T. Materials and methods 14 healthy volunteers and 14 patients with intimal thickening as proven by duplex ultrasound had their carotid arteries imaged at 3 T using a multi-sequence protocol (time-of-flight MR angiography, pre-contrast T1w-, PDw- and T2w sequences in the volunteers, additional post-contrast T1w- and dynamic contrast enhanced sequences in patients). To assess intrascan reproducibility, 10 volunteers were scanned twice within 2 weeks. Results Intrascan reproducibility for quantitative measurements of lumen, wall and outer wall areas was excellent with Intraclass Correlation Coefficients >0.98 and measurement errors of 1.5%, 4.5% and 1.9%, respectively. Patients had larger wall areas than volunteers in both common carotid and internal carotid arteries and smaller lumen areas in internal carotid arteries (p < 0.001). Positive correlations were found between wall area and cardiovascular risk factors such as age, hypertension, coronary heart disease and hypercholesterolemia (Spearman's r = 0.45-0.76, p < 0.05). No significant correlations were found between wall area and body mass index, gender, diabetes or a family history of cardiovascular disease. Conclusion The findings of this study indicate that high resolution carotid black-blood 3 T MR with parallel imaging is a fast, reproducible and robust method to assess carotid atherosclerotic plaque in vivo and this method is ready to be used in clinical practice.

Published
2009

138. Untersuchung myokardialer Kollateralgefäße mit Magnetresonanztomographie bei Patienten mit chronischem koronararteriellem Verschluss

Author

Cyran, Clemens

Subjects
FOS: Medical and Health Sciences, Cardiac MRI, myokardiale Kollateralisierung, Eingefäßerkrankung, Delay, Perfusion
Abstract

In dieser Arbeit wurde mit kardialer MRT Funktion, Perfusion und Vitalität bei 30 Patienten mit koronarer Herzkrankheit und chronischem Gefäßabbruch untersucht. Besonderes Augenmerk wurde auf die transmurale Infarktausdehnung (TID), die Ruheperfusion, die Perfusion unter Adenosin-induzierter Hyperämie sowie die systolische regionale Wandverdickung (RWT) in kollateralabhängigem und antegrad perfundiertem Myokard gelegt. Als neuer Parameter wurde die Verzögerung der Kontrastmittelankunft (Delay) in antegrad perfundiertem und kollateralisiertem Myokard untersucht. Zunächst wurden die Kollateralen koronarangiographisch nach ihrem Vorhandensein und ihrem Füllungsgrad eingeteilt. Hierzu wurde die etablierte koronarangiographische Klassifikation nach Rentrop verwendet. Es folgte die kardiale MRT, mit der myokardiale Funktion und Perfusion zunächst unter Adenosininduzierter Hyperämie und danach in Ruhe untersucht wurden. Zuletzt erfolgte die Untersuchung der Vitalität mittels der late enhancement Technik. Dabei wurde der Zusammenhang zwischen koronarangiographischem Kollateralisierungsgrad und kernspintomographisch bestimmter Perfusion und systolischer, regionaler Wandverdickung ebenso untersucht wie die myokardiale Funktion und Perfusion in Abhängigkeit von der transmuralen Infarktausdehnung (TID). Durch den Einsatz der first-pass Perfusion Technik und der Bestimmung der verzögerten Kontrastmittelanflutung (Delay) ist es möglich, kollateralisiertes Myokard zu identifizieren und von antegrad perfundiertem Myokard mit hoher Sensitivität und Spezifität abzugrenzen. Die Verzögerung der Kontrastmittelanflutung scheint dabei vom angiographisch erhobenen Füllungsgrad der Kollateralen beeinflusst zu sein, ist jedoch unabhängig vom Ausmaß der myokardialen Perfusion. Kollateralisiertes Myokard lässt sich folglich auch dann von antegrad perfundiertem Myokard unterscheiden, wenn die Perfusion sich in einem ähnlichen Bereich bewegt. Bei den Patienten mit einer transmuralen Infarktausdehnung 50% in kollateralisiertem Myokard blieben die Perfusionsparameter in Ruhe und unter Hyperämie sowie die regionale Wanddickenzunahme signifikant unter den Werten,die in antegrad perfundiertem Myokard gemessen wurden. Des Weiteren zeigte sich, dass Funktion und Perfusion in kollateralisiertem Myokard erhalten bleiben, wenn die transmurale Infarktausdehnung

Published
2007
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140. [F]FDG PET accurately differentiates infected and non-infected non-unions after fracture fixation.

Author

Wenter, Vera, Albert, Nathalie, Brendel, Matthias, Fendler, Wolfgang, Cyran, Clemens, Bartenstein, Peter, Friederichs, Jan, Müller, Jan-Philipp, Militz, Matthias, Hacker, Marcus, and Hungerer, Sven

Subjects
FRACTURE fixation, POSITRON emission tomography, COMPOUND fractures, HEALTH outcome assessment, FOLLOW-up studies (Medicine), INFECTION, THERAPEUTICS
Abstract

Purpose: Complete fracture healing is crucial for good patient outcomes. A major complication in the treatment of fractures is non-union. The pathogenesis of non-unions is not always clear, although implant-associated infections play a significant role, especially after surgical treatment of open fractures. We aimed to evaluate the value of [F]FDG PET in suspected infections of non-union fractures. Methods: We retrospectively evaluated 35 consecutive patients seen between 2000 and 2015 with suspected infection of non-union fractures, treated at a level I trauma center. The patients underwent either [F]FDG PET/CT ( N = 24), [F]FDG PET ( N = 11) plus additional CT ( N = 8), or conventional X-ray ( N = 3). Imaging findings were correlated with final diagnosis based on intraoperative culture or follow-up. Results: In 13 of 35 patients (37 %), infection was proven by either positive intraoperative tissue culture ( N = 12) or positive follow-up ( N = 1). [F]FDG PET revealed 11 true-positive, 19 true-negative, three false-positive, and two false-negative results, indicating sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of 85 %, 86 %, 79 %, 90 %, and 86 %, respectively. The SUV was 6.4 ± 2.7 in the clinically infected group and 3.0 ± 1.7 in the clinically non-infected group ( p <0.01). The SUV was 5.3 ± 3.3 in the clinically infected group and 2.6 ± 1.5 in the clinically non-infected group ( p <0.01). Conclusion: [F]FDG PET differentiates infected from non-infected non-unions with high accuracy in patients with suspected infections of non-union fractures, for whom other clinical findings were inconclusive for a local infection. [F]FDG PET should be considered for therapeutic management of non-unions. [ABSTRACT FROM AUTHOR]

Published
2017
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141. 68Ga-TRAP-(RGD)3 Hybrid Imaging for the In Vivo Monitoring of αvß3-Integrin Expression as Biomarker of Anti-Angiogenic Therapy Effects in Experimental Breast Cancer.

Author

Kazmierczak, Philipp M., Todica, Andrei, Gildehaus, Franz-Josef, Hirner-Eppeneder, Heidrun, Brendel, Matthias, Eschbach, Ralf S., Hellmann, Magdalena, Nikolaou, Konstantin, Reiser, Maximilian F., Wester, Hans-Jürgen, Kropf, Saskia, Rominger, Axel, and Cyran, Clemens C.

Subjects
BREAST cancer treatment, GENETICS of breast cancer, BIOMARKERS, GALLIUM, GENE expression, INTEGRINS
Abstract

Objectives: To investigate 68Ga-TRAP-(RGD)3 hybrid imaging for the in vivo monitoring of αvß3-integrin expression as biomarker of anti-angiogenic therapy effects in experimental breast cancer. Materials and Methods: Human breast cancer (MDA-MB-231) xenografts were implanted orthotopically into the mammary fat pads of n = 25 SCID mice. Transmission/emission scans (53 min to 90 min after i.v. injection of 20 MBq 68Ga-TRAP-(RGD)3) were performed on a dedicated small animal PET before (day 0, baseline) and after (day 7, follow-up) a 1-week therapy with the VEGF antibody bevacizumab or placebo (imaging cohort n = 13; therapy n = 7, control n = 6). The target-to-background ratio (TBR, VOImaxtumor/VOImeanmuscle) served as semiquantitative measure of tumor radiotracer uptake. Unenhanced CT data sets were subsequently acquired for anatomic coregistration and morphology-based tumor response assessments (CT volumetry). The imaging results were validated by multiparametric ex vivo immunohistochemistry (αvß3-integrin, microvascular density–CD31, proliferation–Ki-67, apoptosis–TUNEL) conducted in a dedicated immunohistochemistry cohort (n = 12). Results: 68Ga-TRAP-(RGD)3 binding was significantly reduced under VEGF inhibition and decreased in all bevacizumab-treated animals (ΔTBRfollow-up/baseline: therapy -1.07±0.83, control +0.32±1.01, p = 0.022). No intergroup difference in tumor volume development between day 0 and day 7 was observed (Δvolumetherapy 134±77 μL, Δvolumecontrol 132±56 μL, p = 1.000). Immunohistochemistry revealed a significant reduction of αvß3-integrin expression (308±135 vs. 635±325, p = 0.03), microvascular density (CD31, 168±108 vs. 432±70, p = 0.002), proliferation (Ki-67, 5,195±1,002 vs. 7,574±418, p = 0.004) and significantly higher apoptosis (TUNEL, 14,432±1,974 vs. 3,776±1,378, p = 0.002) in the therapy compared to the control group. Conclusions: 68Ga-TRAP-(RGD)3 hybrid imaging allows for the in vivo assessment of αvß3-integrin expression as biomarker of anti-angiogenic therapy effects in experimental breast cancer. [ABSTRACT FROM AUTHOR]

Published
2016
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145. Visualization, imaging and new preclinical diagnostics in radiation oncology

Author

Cyran, Clemens C, primary, Paprottka, Philipp M, additional, Eisenblätter, Michel, additional, Clevert, Dirk A, additional, Rist, Carsten, additional, Nikolaou, Konstantin, additional, Lauber, Kirsten, additional, Wenz, Frederik, additional, Hausmann, Daniel, additional, Reiser, Maximilian F, additional, Belka, Claus, additional, and Niyazi, Maximilian, additional

Published
2014
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148. Regorafenib Effects on Human Colon Carcinoma Xenografts Monitored by Dynamic Contrast-Enhanced Computed Tomography with Immunohistochemical Validation

Author

Cyran, Clemens C., primary, Kazmierczak, Philipp M., additional, Hirner, Heidrun, additional, Moser, Matthias, additional, Ingrisch, Michael, additional, Havla, Lukas, additional, Michels, Alexandra, additional, Eschbach, Ralf, additional, Schwarz, Bettina, additional, Reiser, Maximilian F., additional, Bruns, Christiane J., additional, and Nikolaou, Konstantin, additional

Published
2013
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149. Comparison of symptomatic and asymptomatic atherosclerotic carotid plaques using parallel imaging and 3 T black-blood in vivo CMR

Author

Grimm, Jochen M, primary, Schindler, Andreas, additional, Freilinger, Tobias, additional, Cyran, Clemens C, additional, Bamberg, Fabian, additional, Yuan, Chun, additional, Reiser, Maximilian F, additional, Dichgans, Martin, additional, Freilinger, Caroline, additional, Nikolaou, Konstantin, additional, and Saam, Tobias, additional

Published
2013
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150. In vivo monitoring of sorafenib therapy effects on experimental prostate carcinomas using dynamic contrast-enhanced MRI and macromolecular contrast media

Author

Cyran, Clemens C., primary, Schwarz, Bettina, additional, Paprottka, Philipp M., additional, Sourbron, Steven, additional, von Einem, Jobst C., additional, Dietrich, Olaf, additional, Hinkel, Rabea, additional, Clevert, Dirk A., additional, Bruns, Christiane J., additional, Reiser, Maximilian F., additional, Nikolaou, Konstantin, additional, and Wintersperger, Bernd J., additional

Published
2013
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