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Saam T, Hetterich H, Hoffmann V, Yuan C, Treitl M, Dichgans M, Poppert H, Reiser MF, Bamberg F. Meta-Analyse und systematischer Überblick des prädiktiven Wertes von MRT-basierten Intraplaque Einblutungen für das Auftreten von zerebrovaskulären Ereignissen. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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152
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Thierfelder KM, Baumgarten LV, Klotz E, Baumann AB, Nikolaou K, Reiser MF, Sommer WH. Reabilität und Reproduzierbarkeit einer volumetrischen Auswertung von Perfusionsdefiziten in der CT-Ganzhirnperfusion bei Patienten mit akutem ischämischem Schlaganfall. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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153
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Saam T, Buchholz M, Notohamiprodjo M, Rominger A, Yuan C, Reiser MF, Nikolaou K, Dichgans M, Bayer-Karpinska A, Helck A. Einfluss des positiven Remodelings auf Plaquezusammensetzung und Plaquevulnerabilität: Eine in vivo MRT-Studie der Karotiden. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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154
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Strobl FF, Rist C, Bamberg F, Rominger A, Hacker M, Übleis C, Thierfelder KM, Nikolaou K, Reiser MF, Saam T. Der Einfluss von kardiovaskulären Risikofaktoren auf Inflammation der Gefäßwand und Gefäßverkalkung variiert zwischen unterschiedlichen anatomischen Regionen - eine PET-CT Studie. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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155
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Pomschar A, Gent H, Ertl-Wagner B, Peller M, Baur-Melnyk A, Reiser MF, Notohamiprodjo M. Ösophagusbreischluck mit einem modernen Flachdetektor System und Dosis sparender Technik - Dosisreduktion bei guter Bildqualität. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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156
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Mueller-Lisse UG, Schmitz M, Strube HA, Fischer R, Huber RM, Weber K, Paolini M, Allert S, Mindiuk I, Pichler J, Reiser MF. Mukoviszidose (CF) bei Erwachsenen: Korrelation von MDCT-Lungenmorphologie und Lungenfunktionstests an einem Zentrum. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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157
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Schmid-Tannwald C, Schmid-Tannwald CM, Schramm N, Nikolaou K, Reiser MF, Rist C. Vergleich zwischen der abdominellen MRT inklusive diffusionsgewichteten Sequenzen und der 68Ga-DOTATATE PET/CT in der Detektion von neuroendokrinen Tumoren des Pankreas. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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158
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Grimm JM, Geyer LL, Mück F, Deak Z, Scherr MK, Hetterich H, Kammer N, Notohamiprodjo S, Reiser MF, Wirth S. Bildqualität in Abhängigkeit von der Röhrenspannung bei der Darstellung von Koronaren Stents im CT Unter Verwendung Verschiedener Iterativer Bildrekonstruktionsalgorithmen: Eine Phantomstudie. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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159
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Mueller-Lisse UG, Schmitz M, Guendogar U, Panteleon A, Fischer R, Huber RM, Strube HA, Ashoori N, Reiser MF, Coppenrath EM. Mukoviszidose (CF) bei F508-positiven Erwachsenen: Änderung der Lungenmorphologie in der MDCT über drei Jahre an einem Zentrum. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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160
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Bamberg F, Parhofer KG, Lochner E, Theisen D, Schönberg SO, Reiser MF, Weckbach S. Prädiktiver Wert der Ganzkörper Magnetresonanztomografie für das Auftreten von Kardio-Cerebrovaskulären Ereignissen bei Patienten mit Diabetes Mellitus. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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161
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Thierfelder KM, Baumgarten LV, Meinel FG, Baumann AB, Nikolaou K, Reiser MF, Sommer WH. Prognose des Symptombeginns bei akutem ischämischem Schlaganfall mittels dreidimensionalem Fluss-Volumen-Mismatch in der CT-Ganzhirnperfusion. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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162
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Kramer H, Arnoldi E, Francois CJ, Wentland AL, Nikolaou K, Wintersperger BJ, Reiser MF, Grist TM. MR Angiografie (MRA) der supraaortalen Gefäße bei 3,0 T: intraindividueller Vergleich Gd-basierter Kontrastmittel. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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163
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Marcus RP, Bamberg F, Neumaier K, Reiser MF, Johnson TR. Anpassung und Messung der Dosis bei CT-Untersuchungen von morbid-adipösen Patienten. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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164
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Kazmierczak PM, Cyran CC, Hirner H, Havla L, Schneider M, Dietrich O, Schwarz B, Bruns CJ, Reiser MF, Nikolaou K. DCE-CT Imaging Biomarker zum Monitoring einer Regorafenib-Monotherapie im experimentellen Colonkarzinom-Modell der Ratte mit immunhistochemischer Validierung. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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165
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Notohamiprodjo M, Winter KS, Helck AD, Ingrisch M, Staehler MF, Reiser MF, Nikolaou K. Dynamische kontrastverstärkte MRT der Niere und Nierentumoren: Vergleich der Untersuchung einer Einzelschicht vs. des gesamten Organs/Tumor. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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166
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D'Anastasi M, Otto S, Probst F, Baur-Melnyk A, Reiser MF, Notohamiprodjo M. Evaluation einer T1-w 3D-SPACE Sequenz in der 3T Bildgebung der Kiefernekrosen und der diffusen sklerosierenden Osteomyelitis des Kiefers. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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167
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D'Anastasi M, Notohamiprodjo M, Dürr HR, Reiser MF, Baur-Melnyk A. Tumorlast bei Patienten mit Multiplem Myelom: Serum Beta-2-Mikroglobulin versus Ganzkörper-MRT. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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168
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Treitl M, Eberhardt KM, Maxien D, Reiser MF. Endoleaks nach endovaskulärer Versorgung von Aortenaneurysmen. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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169
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Graser A, Melzer A, Lindner E, Nagel D, Herrmann K, Stieber P, Schirra J, Mansmann U, Reiser MF, Göke B, Kolligs FT. Magnetic resonance colonography for the detection of colorectal neoplasia in asymptomatic adults. Gastroenterology 2013; 144:743-750.e2. [PMID: 23415805 DOI: 10.1053/j.gastro.2012.12.041] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Revised: 12/08/2012] [Accepted: 12/12/2012] [Indexed: 12/19/2022]
Abstract
BACKGROUND & AIMS Colonoscopy is the preferred screening test for colorectal neoplasia; the fecal occult blood test (FOBT) detects neoplasias with low levels of sensitivity. Computed tomographic colonography detects neoplasias with high levels of sensitivity but involves exposure to radiation. We investigated whether magnetic resonance colonography (MRC) can be used to screen for colorectal adenomas and cancers. METHODS We analyzed data from 286 asymptomatic adults (40-82 years old) who underwent 3 Tesla MRC and colonoscopic examinations on the same day. FOBT was performed before bowel preparation. Colonoscopists were initially blinded to the findings on MRC and unblinded after withdrawal from the respective segments. Sensitivities for adenoma and per-patient sensitivities and specificities were calculated based on the unblinded results of colonoscopy. RESULTS We detected 133 adenomas and 2 cancers in 86 patients; 37 adenomas were ≥6 mm, and 20 adenomas were advanced. Sensitivities of MRC and colonoscopy for adenomas ≥6 mm were 78.4% (95% confidence interval [CI], 61.8-90.2) and 97.3% (95% CI, 85.8-99.9); for advanced adenomas these values were 75% (95% CI, 50.9-91.3) and 100% (95% CI, 83.2-100.0), respectively. MRC identified 87.1% (95% CI, 70.2-96.4), colonoscopy 96.8% (95% CI, 83.3-99.9), and FOBT 10.0% (95% CI, 2.1-26.5) of individuals with adenomas ≥6 mm and 83.8% (95% CI, 58.6-96.4), 100% (95% CI, 81.5-100.0), and 17.6% (95% CI, 3.8-43.4) of individuals with advanced neoplasia. Specificities of MRC, colonoscopy, and FOBT for individuals with adenomas ≥6 mm were 95.3% (95% CI, 91.9-97.5), 96.9% (95% CI, 93.9-98.6), and 91.8% (95% CI, 87.6-94.9), respectively. CONCLUSIONS 3 Tesla MRC detects colorectal adenomas ≥6 mm and advanced neoplasia with high levels of sensitivity and specificity. Although MRC detects colorectal neoplasia with lower levels of sensitivity than colonoscopy, it strongly outperforms one-time FOBT.
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Affiliation(s)
- Anno Graser
- Department of Clinical Radiology, University of Munich, Munich, Germany.
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170
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Geyer LL, Körner M, Hempel R, Deak Z, Mueck FG, Linsenmaier U, Reiser MF, Wirth S. Evaluation of a dedicated MDCT protocol using iterative image reconstruction after cervical spine trauma. Clin Radiol 2013; 68:e391-6. [PMID: 23537577 DOI: 10.1016/j.crad.2012.11.025] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 11/26/2012] [Accepted: 11/09/2012] [Indexed: 12/20/2022]
Abstract
AIM To evaluate radiation exposure for 64-row computed tomography (CT) of the cervical spine comparing two optimized protocols using filtered back projection (FBP) and adaptive statistical iterative reconstruction (ASIR), respectively. MATERIALS AND METHODS Sixty-seven studies using FBP (scanner 1) were retrospectively compared with 80 studies using ASIR (scanner 2). The key scanning parameters were identical (120 kV dose modulation, 64 × 0.625 mm collimation, pitch 0.531:1). In protocol 2, the noise index (NI) was increased from 5 to 25, and ASIR and the high-definition (HD) mode were used. The scan length, CT dose index (CTDI), and dose-length product (DLP) were recorded. The image quality was analysed subjectively by using a three-point scale (0; 1; 2), and objectively by using a region of interest (ROI) analysis. Mann-Whitney U and Wilcoxon's test were used. RESULTS In the FBP group, the mean CTDI was 21.43 mGy, mean scan length 186.3 mm, and mean DLP 441.15 mGy cm. In the ASIR group, the mean CTDI was 9.57 mGy, mean scan length 195.21 mm, and mean DLP 204.23 mGy cm. The differences were significant for CTDI and DLP (p < 0.001) and scan length (p = 0.01). There was no significant difference in the subjective image quality (p > 0.05). The estimated mean effective dose decreased from 2.38 mSv (FBP) to 1.10 mSv (ASIR). CONCLUSION The radiation dose of 64-row MDCT can be reduced to a level comparable to plain radiography without loss of subjective image quality by implementation of ASIR in a dedicated cervical spine trauma protocol. These results might contribute to an improved relative risk-to-benefit ratio and support the justification of CT as a first-line imaging tool to evaluate cervical spine trauma.
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Affiliation(s)
- L L Geyer
- Department for Clinical Radiology, University Hospital LMU Munich, Munich, Germany.
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171
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Meinel FG, Schwab F, Schleede S, Bech M, Herzen J, Achterhold K, Auweter S, Bamberg F, Yildirim AÖ, Bohla A, Eickelberg O, Loewen R, Gifford M, Ruth R, Reiser MF, Pfeiffer F, Nikolaou K. Diagnosing and mapping pulmonary emphysema on X-ray projection images: incremental value of grating-based X-ray dark-field imaging. PLoS One 2013; 8:e59526. [PMID: 23555692 PMCID: PMC3608711 DOI: 10.1371/journal.pone.0059526] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Accepted: 02/15/2013] [Indexed: 02/01/2023] Open
Abstract
PURPOSE To assess whether grating-based X-ray dark-field imaging can increase the sensitivity of X-ray projection images in the diagnosis of pulmonary emphysema and allow for a more accurate assessment of emphysema distribution. MATERIALS AND METHODS Lungs from three mice with pulmonary emphysema and three healthy mice were imaged ex vivo using a laser-driven compact synchrotron X-ray source. Median signal intensities of transmission (T), dark-field (V) and a combined parameter (normalized scatter) were compared between emphysema and control group. To determine the diagnostic value of each parameter in differentiating between healthy and emphysematous lung tissue, a receiver-operating-characteristic (ROC) curve analysis was performed both on a per-pixel and a per-individual basis. Parametric maps of emphysema distribution were generated using transmission, dark-field and normalized scatter signal and correlated with histopathology. RESULTS Transmission values relative to water were higher for emphysematous lungs than for control lungs (1.11 vs. 1.06, p<0.001). There was no difference in median dark-field signal intensities between both groups (0.66 vs. 0.66). Median normalized scatter was significantly lower in the emphysematous lungs compared to controls (4.9 vs. 10.8, p<0.001), and was the best parameter for differentiation of healthy vs. emphysematous lung tissue. In a per-pixel analysis, the area under the ROC curve (AUC) for the normalized scatter value was significantly higher than for transmission (0.86 vs. 0.78, p<0.001) and dark-field value (0.86 vs. 0.52, p<0.001) alone. Normalized scatter showed very high sensitivity for a wide range of specificity values (94% sensitivity at 75% specificity). Using the normalized scatter signal to display the regional distribution of emphysema provides color-coded parametric maps, which show the best correlation with histopathology. CONCLUSION In a murine model, the complementary information provided by X-ray transmission and dark-field images adds incremental diagnostic value in detecting pulmonary emphysema and visualizing its regional distribution as compared to conventional X-ray projections.
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Affiliation(s)
- Felix G Meinel
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany.
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172
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Schramm N, Englhart E, Schlemmer M, Hittinger M, Übleis C, Becker CR, Reiser MF, Berger F. Tumor response and clinical outcome in metastatic gastrointestinal stromal tumors under sunitinib therapy: comparison of RECIST, Choi and volumetric criteria. Eur J Radiol 2013; 82:951-8. [PMID: 23518148 DOI: 10.1016/j.ejrad.2013.02.034] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2012] [Revised: 01/21/2013] [Accepted: 02/16/2013] [Indexed: 11/30/2022]
Abstract
PURPOSE Purpose of the study was to compare radiological treatment response according to RECIST, Choi and volumetry in GIST-patients under 2nd-line-sunitinib-therapy and to correlate the results of treatment response assessment with disease-specific survival (DSS). PATIENTS AND METHODS 20 patients (mean: 60.7 years; 12 male/8 female) with histologically proven GIST underwent baseline-CT of the abdomen under imatinib and follow-up-CTs 3 months and 1 year after change to sunitinib. 68 target lesions (50 hepatic, 18 extrahepatic) were investigated. Therapy response (partial response (PR), stable disease (SD), progressive disease (PD)) was evaluated according to RECIST, Choi and volumetric criteria. Response according to the different assessment systems was compared and correlated to the DSS of the patients utilizing Kaplan-Meier statistics. RESULTS The mean DSS (in months) of the response groups 3 months after therapy change was: RECIST: PR (0/20); SD (17/20): 30.4 (months); PD (3/20) 11.6. Choi: PR (10/20) 28.6; SD (8/20) 28.1; PD (2/20) 13.5. Volumetry: PR (4/20) 29.6; SD (11/20) 29.7; PD (5/20) 17.2. Response groups after 1 year of sunitinib showed the following mean DSS: RECIST: PR (3/20) 33.6; SD (9/20) 29.7; PD (8/20) 20.3. Choi: PR (10/20) 21.5; SD (4/20) 42.9; PD (6/20) 23.9. Volumetry: PR (6/20) 27.3; SD (5/20) 38.5; PD (9/20) 19.3. CONCLUSION One year after modification of therapy, only partial response according to RECIST indicated favorable survival in patients with GIST. The value of alternate response assessment strategies like Choi criteria for prediction of survival in molecular therapy still has to be demonstrated.
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Affiliation(s)
- N Schramm
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Marchioninistrasse 15, 81377 Munich, Germany.
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173
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Meinel FG, Graef A, Thieme SF, Bamberg F, Schwarz F, Sommer WH, Helck AD, Neurohr C, Reiser MF, Johnson TR. Assessing Pulmonary Perfusion in Emphysema. Invest Radiol 2013; 48:79-85. [DOI: 10.1097/rli.0b013e3182778f07] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract
Dilated cardiomyopathy (DCM) is the most common type of cardiomyopathy with a prevalence of 1 out of 2,500 in adults. Due to mild clinical symptoms in the early phase of the disease, the true prevalence is probably even much higher. Patients present with variable clinical symptoms ranging from mild systolic impairment of left ventricular function to congestive heart failure. Even sudden cardiac death may be the first clinical symptom of DCM. The severity of the disease is defined by the degree of impairment of global left ventricular function. Arrhythmias, such as ventricular or supraventricular tachycardia, atrioventricular (AV) block, ventricular extrasystole and atrial fibrillation are common cardiac manifestations of DCM. Magnetic resonance imaging (MRI) plays an important role in the exact quantification of functional impairment of both ventricles and in the evaluation of regional wall motion abnormalities. With its excellent ability for the assessment of myocardial structure, it is becoming increasingly more important for risk stratification and therapy guidance.
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Affiliation(s)
- M D'Anastasi
- Institut für Klinische Radiologie, Klinikum der Ludwig-Maximilians-Universität München, Campus Grosshadern, Deutschland.
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175
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Theisen D, Reiser MF. [Cardiomyopathies and myocarditis]. Radiologe 2012; 53:7. [PMID: 23262455 DOI: 10.1007/s00117-012-2379-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- D Theisen
- Institut für Klinische Radiologie, Klinikum der Ludwig-Maximilians-Universität München, Campus Grosshadern, Deutschland
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Raya JG, Melkus G, Adam-Neumair S, Dietrich O, Mützel E, Reiser MF, Putz R, Kirsch T, Jakob PM, Glaser C. Diffusion-tensor imaging of human articular cartilage specimens with early signs of cartilage damage. Radiology 2012; 266:831-41. [PMID: 23238155 DOI: 10.1148/radiol.12120954] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To assess the use of diffusion-tensor (DT) imaging of articular cartilage to detect and grade early cartilage damage in human specimens with early signs of cartilage damage. MATERIALS AND METHODS This study was approved by the institutional review board. Forty-three cartilage-on-bone samples drilled from 21 human patellae were examined with 17.6-T magnetic resonance (MR) imaging and a diffusion-weighted spin-echo sequence (spatial resolution, 50 × 100 × 800 μm). Subsequently, samples underwent histologic analysis with safranin O staining. Cartilage damage on safranin O histologic slides was quantified with Osteoarthritis Research Society International (OARSI) grades; grades ranged from 0 (healthy) to 6 (bone remodeling). Maps of longitudinal diffusivity (λ(l)), transverse diffusivity (λ(t)), mean diffusivity (MD), and fractional anisotropy (FA) were calculated. Cartilage was segmented, and region of interest (ROI) analysis was performed and compared with histologic findings. Significant differences in MR parameters between the OARSI groups were assessed with the Tukey test. The value of DT imaging in the diagnosis and grading of cartilage damage was assessed with logistic regression analysis. RESULTS Samples had OARSI grades of 0 (n = 14), 1 (n = 11), 2 (n = 12), 3 (n = 4), and 4 (n = 2). Samples with an OARSI grade greater than 0 had significantly increased λ(l), λ(t), and MD (7%-25% increase) in the superficial cartilage growing deeper into cartilage with increasing OARSI grade. Samples with an OARSI grade greater than 0 showed significantly decreased FA in the deep cartilage (-25% to -35% decrease), suggesting that changes in the collagen architecture may occur early in cartilage degradation. DTI showed excellent performance in the detection of cartilage damage (accuracy, 0.95; 41 of 43 samples) and good performance in the grading of cartilage damage (accuracy, 0.74; 32 of 43 samples). CONCLUSION DT imaging of articular cartilage can enable physicians to detect and grade early cartilage damage.
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Affiliation(s)
- José G Raya
- Department of Radiology, New York University Langone Medical Center, 660 First Ave, 4th Floor, New York, NY 10016, USA.
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Weber K, Berger F, Mustafa M, Reiser MF, Bartenstein P, Haug A. [SPECT/CT for staging and treatment monitoring in oncology. Applications in differentiated thyroid cancer and liver tumors]. Radiologe 2012; 52:646-52. [PMID: 22710988 DOI: 10.1007/s00117-011-2267-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
CLINICAL/METHODICAL ISSUE Hybrid imaging of function and morphology has gained significant importance for lesion detection and treatment monitoring in oncology. In patients with differentiated thyroid carcinoma (DTC) a planar whole body scan is carried out after radioiodine therapy (RIT) for staging. However, due to limited spatial resolution the diagnostic accuracy of this scintigraphy method is impaired. Radioembolization utilizing (90)Yttrium loaded micro-spheres by selective internal radiotherapy (SIRT) allows a minor invasive therapy of primary and secondary liver tumors. In order to avoid side effects of the micro-spheres caused by an outflow into intestines, stomach or lungs, imaging the arteries supplying the liver has to be performed by means of technetium-99m macroaggregated albumin ((99m)Tc-MAA) and scintigraphy. The limited morphological information supplied by scintigraphy is again a challenge in treatment monitoring. STANDARD RADIOLOGICAL/NUCLEAR MEDICAL METHODS: (131)Iodine whole body scanning is used for staging in patients with DTC 3-4 days after ablation. Monitoring of the tumor marker thyroglobulin and selective radioiodine whole body scans are available for patients with a high risk profile in the further follow-up with imaging of the arteries supplying the liver by means of (99m)Tc-MAA scintigraphy in preparation of SIRT. METHODICAL INNOVATIONS Single photon emission computed tomography/computed tomography (SPECT/CT) of the neck and thorax with a therapeutic activity of radioiodine for staging after ablation. Techniques include imaging of arteries supplying the liver by means of (99m)Tc-MAA SPECT/CT before SIRT and evaluation and quantification of the uptake of liver tumors, especially in comparison to the uptake of liver parenchyma by means of SPECT/CT. PERFORMANCE Due to the integration of combined functional and morphological information SPECT/CT can be used to characterize the morphology and iodine uptake of lesions more accurately, resulting in optimized staging in patients with DTC in comparison to whole body iodine scans and SPECT/CT provides more accurate imaging of the arterial supply of the liver and of potential outflows of micro-spheres into other organs. SPECT/CT allows evaluation and quantification of the uptake of liver tumors. ACHIEVEMENTS Improved postablative staging in patients with differentiated thyroid cancer by SPECT/CT in comparison to radioiodine whole body scans can be achieved. Improved planning and monitoring of SIRT therapies utilizing SPECT/CT leads to optimized therapeutic doses within liver lesions. PRACTICAL RECOMMENDATIONS Integration of SPECT/CT into the clinical standard for postablative staging in patients with DTC is recommended as well as utilization of SPECT/CT during the planning process, for dose calculation and treatment monitoring of SIRT therapies.
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Affiliation(s)
- K Weber
- Institut für Klinische Radiologie, Klinikum der Ludwig-Maximilians-Universität München, Campus Innenstadt, München, Deutschland
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178
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Schwab F, Schleede S, Hahn D, Bech M, Herzen J, Auweter S, Bamberg F, Achterhold K, Yildirim AÖ, Bohla A, Eickelberg O, Loewen R, Gifford M, Ruth R, Reiser MF, Nikolaou K, Pfeiffer F, Meinel FG. Comparison of contrast-to-noise ratios of transmission and dark-field signal in grating-based X-ray imaging for healthy murine lung tissue. Z Med Phys 2012; 23:236-42. [PMID: 23219282 DOI: 10.1016/j.zemedi.2012.11.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 10/25/2012] [Accepted: 11/08/2012] [Indexed: 02/01/2023]
Abstract
PURPOSE An experimental comparison of the contrast-to-noise ratio (CNR) between transmission and dark-field signals in grating-based X-ray imaging for ex-vivo murine lung tissue. MATERIALS AND METHODS Lungs from three healthy mice were imaged ex vivo using a laser-driven compact synchrotron X-ray source. Background noise of transmission and dark-field signal was quantified by measuring the standard deviation in a region of interest (ROI) placed in a homogeneous area outside the specimen. Image contrast was quantified by measuring the signal range in rectangular ROIs placed in central and peripheral lung parenchyma. The relative contrast gain (RCG) of dark-field over transmission images was calculated as CNRDF / CNRT. RESULTS In all images, there was a trend for contrast-to-noise ratios of dark-field images (CNRDF) to be higher than for transmission images (CNRT) for all ROIs (median 61 vs. 38, p=0.10), but the difference was statistically significant only for peripheral ROIs (61 vs. 32, p=0.03). Median RCG was >1 for all ROIs (1.84). RCG values were significantly smaller for central ROIs than for peripheral ROIs (1.34 vs. 2.43, p=0.03). CONCLUSION The contrast-to-noise ratio of dark-field images compares more favorably to the contrast-to-noise ratio of transmission images for peripheral lung regions as compared to central regions. For any specific specimen, a calculation of the RCG allows comparing which X-ray modality (dark-field or transmission imaging) produces better contrast-to-noise characteristics in a well-defined ROI.
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Affiliation(s)
- Felix Schwab
- Institute for Clinical Radiology, Ludwig Maximilians-University Hospital Munich, Marchioninistr. 15, 81377 München, Germany.
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179
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Mueller S, Keeser D, Reiser MF, Teipel S, Meindl T. Functional and structural MR imaging in neuropsychiatric disorders, part 2: application in schizophrenia and autism. AJNR Am J Neuroradiol 2012; 33:2033-7. [PMID: 22173749 DOI: 10.3174/ajnr.a2800] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
SUMMARY During the past decade, the application of advanced MR imaging techniques in neuropsychiatric disorders has seen a rapid increase. Disease-specific alterations in brain function can be assessed by fMRI. Structural GM and WM properties are increasingly investigated by DTI and voxel-based approaches like VBM. These methods provide neurobiologic correlates for brain architecture and function, evaluation tools for therapeutic approaches, and potential early markers for diagnosis. Having provided insight into principles of functional and structural imaging and delineated common findings in mild cognitive impairment and Alzheimer disease in Part 1 of this review, we will now focus on autism and schizophrenia as common psychiatric disorders covering different stages of the life span. This review concludes by summarizing current applications, limitations, and future prospects in the field of MR imaging-based neuroimaging.
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Affiliation(s)
- S Mueller
- Institute of Clinical Radiology, University Hospitals Munich, Marchioninistr 15, 81377 Munich.
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180
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Geyer LL, Scherr M, Körner M, Wirth S, Deak P, Reiser MF, Linsenmaier U. Imaging of acute pulmonary embolism using a dual energy CT system with rapid kVp switching: Initial results. Eur J Radiol 2012; 81:3711-8. [DOI: 10.1016/j.ejrad.2011.02.043] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Accepted: 02/22/2011] [Indexed: 11/15/2022]
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181
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Grimm JM, Nikolaou K, Schindler A, Hettich R, Heigl F, Cyran CC, Schwarz F, Klingel R, Karpinska A, Yuan C, Dichgans M, Reiser MF, Saam T. Characteristics of carotid atherosclerotic plaques of chronic lipid apheresis patients as assessed by in vivo high-resolution CMR--a comparative analysis. J Cardiovasc Magn Reson 2012; 14:80. [PMID: 23194143 PMCID: PMC3524023 DOI: 10.1186/1532-429x-14-80] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Accepted: 11/16/2012] [Indexed: 11/30/2022] Open
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 <0.05 was considered statistically significant. RESULTS Patients in the LA-group were younger (63.5 vs. 73.9. years, p<0.05), had a higher prevalence of hypercholesterolemia and of established coronary heart disease in patients and in first-degree relatives (p<0.05, respectively). LA-patients had smaller maximum wall areas (49.7 vs. 59.6mm2, p<0.05), showed lower prevalence of lipid cores (28.1% vs. 56.3%, p<0.05) and the lipid content was smaller than in the control group (5.0 vs. 11.6%, p<0.05). Minimum lumen areas and maximum total vessel areas did not differ significantly between both groups. 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.
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Affiliation(s)
- Jochen M Grimm
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Pettenkoferstr. 8a, 80336, Munich, Germany
| | - Konstantin Nikolaou
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Pettenkoferstr. 8a, 80336, Munich, Germany
| | - Andreas Schindler
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Pettenkoferstr. 8a, 80336, Munich, Germany
| | - Reinhard Hettich
- Medizinisches Versorgungszentrum Kempten-Allgäu, Kempten-Allgäu, Germany
| | - Franz Heigl
- Medizinisches Versorgungszentrum Kempten-Allgäu, Kempten-Allgäu, Germany
| | - Clemens C Cyran
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Pettenkoferstr. 8a, 80336, Munich, Germany
| | - Florian Schwarz
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Pettenkoferstr. 8a, 80336, Munich, Germany
| | | | - Anna Karpinska
- Institute for Stroke and Dementia Research, Ludwig-Maximilians-University Hospital Munich, Munich, Germany
| | - Chun Yuan
- Department of Radiology, University of Washington School of Medicine, Seattle, USA
| | - Martin Dichgans
- Institute for Stroke and Dementia Research, Ludwig-Maximilians-University Hospital Munich, Munich, Germany
| | - Maximilian F Reiser
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Pettenkoferstr. 8a, 80336, Munich, Germany
| | - Tobias Saam
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Pettenkoferstr. 8a, 80336, Munich, Germany
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182
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Braunagel M, Schwarz F, Knösel T, Reiser MF, Graser A. [Unclear abdominal tumor in pulmonary lymphangioleiomyomatosis]. Radiologe 2012. [PMID: 23178789 DOI: 10.1007/s00117-012-2414-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- M Braunagel
- Institut für Klinische Radiologie, Klinikum der Ludwig-Maximilians-Universität München, Campus Grosshadern, Deutschland.
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183
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Deák Z, Grimm JM, Treitl M, Geyer LL, Linsenmaier U, Körner M, Reiser MF, Wirth S. Filtered back projection, adaptive statistical iterative reconstruction, and a model-based iterative reconstruction in abdominal CT: an experimental clinical study. Radiology 2012; 266:197-206. [PMID: 23169793 DOI: 10.1148/radiol.12112707] [Citation(s) in RCA: 197] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
PURPOSE To compare objective and subjective image quality parameters of three image reconstruction algorithms of different generations at routine multidetector computed tomographic (CT) examinations of the abdomen. MATERIALS AND METHODS This institutional review board-approved study included 22 consecutive patients (mean age, 56.1 years ± 15.8 [standard deviation]; mean weight, 79.1 kg ± 14.8) who underwent routine CT examinations of the abdomen. A low-contrast phantom was used for objective quality control. Raw data sets were reconstructed by using filtered back projection (FPB), adaptive statistical iterative reconstruction (ASIR), and a model-based iterative reconstruction (MBIR). Radiologists used a semiquantitative scale (-3 to +3) to rate subjective image quality and artifacts, comparing both FBP and MBIR images with ASIR images. The Wilcoxon test and the intraclass correlation coefficient were used to evaluate the data. Measurements of objective noise and CT numbers of soft tissue structures were compared with analysis of variance. RESULTS The phantom study revealed an improved detectability of low-contrast targets for MBIR compared with ASIR or FBP. Subjective ratings showed higher image quality for MBIR, with better resolution (median value, 2; range, 1 to 3), lower noise (2; range, 1 to 3), and finer contours (2; range, 1 to 2) compared with ASIR (all P < .001). FBP performed inferiorly (0, range, -2 to 0]; -1 [range, -3 to 0]; 0 [range, -1 to 0], respectively; all, P < .001). Mean interobserver correlation was 0.9 for image perception and 0.7 for artifacts. Objective noise for FBP was 14%-68% higher and for MBIR was 18%-47% lower than that for ASIR (P < .001). CONCLUSION The MBIR algorithm considerably improved objective and subjective image quality parameters of routine abdominal multidetector CT images compared with those of ASIR and FBP.
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Affiliation(s)
- Zsuzsanna Deák
- Department for Clinical Radiology, Ludwig-Maximilians-University, Campus Innenstadt, Nussbaumstrasse 20, 80336 Munich, Germany.
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184
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Péporté ARJ, Sommer WH, Nikolaou K, Reiser MF, Zech CJ. Imaging features of intrahepatic cholangiocarcinoma in Gd-EOB-DTPA-enhanced MRI. Eur J Radiol 2012; 82:e101-6. [PMID: 23159401 DOI: 10.1016/j.ejrad.2012.10.010] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Revised: 10/22/2012] [Accepted: 10/24/2012] [Indexed: 02/06/2023]
Abstract
OBJECTIVE The aim of this study is to describe the imaging features of intrahepatic cholangiocarcinoma in Gd-EOB-DTPA-enhanced MRI and to determine whether it results in improved tumour conspicuity of cholangiocarcinoma. MATERIALS AND METHODS Fifty-four patients with histologically proven intrahepatic cholangiocarcinoma underwent MRI of the liver using a 1.5T MR-scanner with Gadoxetic acid disodium (Gd-EOB-DTPA; Eovist/Primovist, Bayer Healthcare, Berlin, Germany). The standard imaging protocol included a T2w multi-shot TSE sequence with fat saturation (fs), a T2w single shot sequence without fs and a T1w 3D GRE sequences with fs (unenhanced and arterial, portovenous, late venous and hepatobiliary phase). Two board certified radiologists experienced in liver MRI (5 and 10 years experience) evaluated retrospectively all MRI scans qualitatively and quantitatively. Signal was measured with region-of-interests (ROI) and signal-to-noise (SNR) as well as contrast-to-noise (CNR) was calculated. Statistical significance was tested with an ANOVA and a pairwise Wilcoxon rank test. RESULTS All intrahepatic cholangiocarcinomas presented as hypointense lesions in the late venous and hepatobiliary phase. Images in the hepatobiliary phase showed the highest lesion conspicuity, i.e. n=9 blurred (16.6%), n=31 moderate (57.4%) and n=14 sharp (26%). This was significantly higher than the lesion conspicuity of all other sequences or phases. Furthermore, the CNR was the highest in this sequence with 76.8±51.3, with significantly higher values than the CNR of the unenhanced T1w sequence (CNR: 35.6±21.0; p<0.0001) and the arterial phase images (CNR: 53.6±36.8; p<0.001). The hepatobiliary phase images showed a SNR of 97.3±59.7 (p<0.001) and thus was significantly different from the unenhanced T1w sequence (SNR: 60.4±35.3; p<0.001), whereas the increase in SNR from the late venous to hepatobiliary phase was neglectable, indicating that no liver-specific contrast uptake is present in cholangiocarcinoma. CONCLUSION Intrahepatic cholangiocarcinoma presents as a hypointense lesion in Gd-EOB-DTPA-enhanced MRI in late venous phase images. The lesion conspicuity as well as CNR was highest in the hepatobiliary phase. Consequently, hepatobiliary phase images in Gd-EOB-DTPA-enhanced MRI images might be helpful for therapy planning due to the exact depiction of the tumour borders.
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Affiliation(s)
- Anne R J Péporté
- Department of Clinical Radiology, University Hospital Munich-Grosshadern, Ludwig-Maximilians University, Munich, Germany
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185
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Meinel FG, Schramm N, Haug AR, Graser A, Reiser MF, Rist C. [Importance of PET/CT for imaging of colorectal cancer]. Radiologe 2012; 52:529-36. [PMID: 22618625 DOI: 10.1007/s00117-011-2284-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
CLINICAL/METHODICAL ISSUE Fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) has emerged as a very useful imaging modality in the management of colorectal carcinoma. Data from the literature regarding the role of PET/CT in the initial diagnosis, staging, radiotherapy planning, response monitoring and surveillance of colorectal carcinoma is presented. Future directions and economic aspects are discussed. STANDARD RADIOLOGICAL METHODS Computed tomography (CT), magnetic resonance imaging (MRI) and FDG-PET for colorectal cancer and endorectal ultrasound for rectal cancer. METHODICAL INNOVATIONS Combined FDG-PET/CT. PERFORMANCE While other imaging modalities allow superior visualization of the extent and invasion depth of the primary tumor, PET/CT is most sensitive for the detection of distant metastases of colorectal cancer. ACHIEVEMENTS We recommend a targeted use of PET/CT in cases of unclear M staging, prior to metastasectomy and in suspected cases of residual or recurrent colorectal carcinoma with equivocal conventional imaging. The role of PET/CT in radiotherapy planning and response monitoring needs to be determined. Currently there is no evidence to support the routine use of PET/CT for colorectal screening, staging or surveillance. PRACTICAL RECOMMENDATIONS To optimally exploit the synergy between morphologic and functional information, FDG-PET should generally be performed as an integrated FDG-PET/CT with a contrast-enhanced CT component in colorectal carcinoma.
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Affiliation(s)
- F G Meinel
- Institut für Klinische Radiologie, Klinikum der Ludwig-Maximilians-Universität München, Campus Großhadern, Marchioninistr. 15, 81377, München, Deutschland.
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186
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Meinel FG, Nikolaou K, Weidenhagen R, Hellbach K, Helck A, Bamberg F, Reiser MF, Sommer WH. Time-resolved CT angiography in aortic dissection. Eur J Radiol 2012; 81:3254-61. [DOI: 10.1016/j.ejrad.2012.03.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Revised: 02/26/2012] [Accepted: 03/05/2012] [Indexed: 11/24/2022]
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187
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Notohamiprodjo M, Horng A, Kuschel B, Paul D, Li G, Raya JG, Reiser MF, Glaser C. 3D-imaging of the knee with an optimized 3D-FSE-sequence and a 15-channel knee-coil. Eur J Radiol 2012; 81:3441-9. [DOI: 10.1016/j.ejrad.2012.04.020] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2012] [Revised: 04/20/2012] [Accepted: 04/21/2012] [Indexed: 11/15/2022]
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188
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Mueller S, Keeser D, Reiser MF, Teipel S, Meindl T. Functional and structural MR imaging in neuropsychiatric disorders, Part 1: imaging techniques and their application in mild cognitive impairment and Alzheimer disease. AJNR Am J Neuroradiol 2012; 33:1845-50. [PMID: 22173754 DOI: 10.3174/ajnr.a2799] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
During the past decade, the application of advanced MR imaging techniques in neuropsychiatric disorders has seen a rapid increase. Disease-specific alterations in brain function can be assessed by fMRI. Structural GM and WM properties are increasingly investigated by DTI and voxel-based approaches like VBM. These methods provide neurobiologic correlates for brain architecture and function, evaluation tools for therapeutic approaches, and potential early markers for diagnosis. The aim of this review was to provide insight into the principles of functional and structural imaging and to delineate major findings in MCI, AD (Part 1), autism, and schizophrenia (Part 2), which are common psychiatric disorders covering different stages of the life span. Part 2 will conclude by summarizing current applications, limitations, and future prospects in the field of MR imaging-based neuroimaging.
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Affiliation(s)
- S Mueller
- Institute of Clinical Radiology, University Hospitals Munich, 81377 Munich.
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189
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Trumm CG, Pahl A, Helmberger TK, Jakobs TF, Zech CJ, Stahl R, Paprottka PM, Sandner TA, Reiser MF, Hoffmann RT. CT fluoroscopy-guided percutaneous vertebroplasty in spinal malignancy: technical results, PMMA leakages, and complications in 202 patients. Skeletal Radiol 2012; 41:1391-400. [PMID: 22286549 DOI: 10.1007/s00256-012-1365-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2011] [Revised: 10/17/2011] [Accepted: 01/09/2012] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To retrospectively evaluate the incidence and clinical impact of local polymethylmethacrylate (PMMA) leaks and pulmonary cement embolisms occurring under CT fluoroscopy-guided vertebroplasty of symptomatic malignant vertebral osteolyses. MATERIALS AND METHODS From December 2001 to June 2009, 202 cancer patients (116 women, 86 men; age 63.2±8.6 years) with painful malignant vertebral osteolyses underwent vertebroplasty, with or without vertebral compression fracture. A total of 331 vertebrae were treated in 231 sessions under CT fluoroscopy guidance (120 kV; 10–25 mA; single slice, 4-, 16-, and 128-row CT). In the pre-vertebroplasty CT, the following items were assessed: osteolytic destruction (0, ≤25, ≤50, ≤75, or ≤100%) of vertebral cross-sectional area, posterior wall, and circumference; presence of perivertebral and degree of epidural (no, mild, moderate) soft tissue involvement. Local PMMA leaks were analyzed using the post-vertebroplasty CT. Pulmonary cement embolisms were evaluated in all patients having undergone radiography (CR; n053) or CT (n088) of the chest after vertebroplasty due to their underlying disease. Patient charts were reviewed regarding adverse events. RESULTS Of 331 treated vertebrae, 32, 20.2, and 15.7% showed more than 50% osteolytic involvement of the vertebral cross-sectional area, posterior wall, and circumference, respectively. Mild or moderate epidural involvement was seen in 13.0 and 8.4%. Local PMMA leakage rate was 58.6% (194 of 331 vertebrae). Pulmonary cement embolisms (segmental, n010; central, n01) were seen after 7.8% of the procedures with follow-up imaging of the chest. No major complications occurred within a 30-day period after vertebroplasty. CONCLUSION Vertebroplasty of spinal malignancy can be safely performed under CT fluoroscopy guidance even in patients with substantial osteolytic involvement. In our patient collective, PMMA leaks and pulmonary cement embolisms visualized in post-procedural radiography and CT images had no clinical impact.
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Affiliation(s)
- Christoph G Trumm
- Department of Clinical Radiology, Klinikum der Ludwig-Maximilians-Universität München-Großhadern, Marchioninistrasse 15, 81377 Munich, Germany.
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190
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Johnson TRC, Himsl I, Hellerhoff K, Mayr D, Rjosk-Dendorfer D, Ditsch N, Krauss B, Friese K, Reiser MF, Lenhard MS. Dual-energy CT for the evaluation of silicone breast implants. Eur Radiol 2012; 23:991-6. [PMID: 23064715 DOI: 10.1007/s00330-012-2667-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 08/28/2012] [Accepted: 09/08/2012] [Indexed: 01/01/2023]
Abstract
OBJECTIVE The evaluation of breast implants for rupture is currently the domain of ultrasound and MRI, while mammography is of very limited diagnostic value. Recently, specific visualisation of silicone has become feasible using dual-energy CT. Our objective was to evaluate whether it is feasible to identify silicone in breast implants by dual-energy CT and to reliably diagnose or rule out ruptures. METHODS Seven silicone breast implant specimens were examined on dual-source CT at 100- and 140-kV tube potential with a 0.8-mm tin filter (collimation 128 × 0.6 mm, current-time products 165 and 140 mAsref with modulation, rotation time 0.28 s, pitch 0.55). Two patients scheduled for implant removal or replacement were examined with identical parameters. RESULTS The silicone of the implant specimens showed a strong dual-energy signal. In one patient, both implants were intact, while a rupture was identified in the other patient. Ultrasound, MRI, surgical findings and histology confirmed the dual-energy CT diagnosis. CONCLUSION Dual-energy CT may serve as an alternative technique for speedy evaluation of silicone breast implants. Specific clinical studies are required to determine the diagnostic accuracy and define indications for this technique.
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Affiliation(s)
- Thorsten R C Johnson
- Department of Clinical Radiology, University of Munich-Grosshadern Campus, Marchioninistr. 15, 81377 Munich, Germany.
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191
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Ziegeler E, Grimm JM, Wirth S, Uhl M, Reiser MF, Scherr MK. Computed tomography scout views vs. conventional radiography in body-packers - delineation of body-packs and radiation dose in a porcine model. Eur J Radiol 2012; 81:3883-9. [PMID: 23017196 DOI: 10.1016/j.ejrad.2012.06.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Accepted: 06/22/2012] [Indexed: 01/08/2023]
Abstract
OBJECTIVE To compare abdominal computed tomography (CT) scout views with conventional radiography regarding radiation dose and delineation of drug packages in a porcine body-packer model. MATERIALS AND METHODS Nine samples of illicit drugs packed in ovoid plastic containers were consecutively placed in the rectum of a 121.5 kg pig cadaver. Antero-posterior and lateral scout views were obtained at 120 kVp and 80 mA, 150 mA and 200 mA, respectively, using a 64-row MDCT. Scout views were compared with conventional abdominal antero-posterior radiographs (77 kV and 106 ± 13 mAs). Visibility of three body pack characteristics (wrapping, content, shape) was rated independently by two radiologists and summarized to a delineation score ranging from 0 to 9 with a score ≥ 6 representing sufficient delineation. Mean delineation scores were calculated for each conventional radiography and single plane scout view separately and for a combined rating of antero-posterior and lateral scout views. RESULTS Even the lowest single plane scout view delineation score (5.3 ± 2.0 for 80 mA lateral; 0.4 mSv; sensitivity=44%) was significantly higher than for conventional radiographs (3.1 ± 2.5, p<0.001; 2.4 ± 0.3 mSv; sensitivity=11%). Combined reading of antero-posterior and lateral scout views 80 mA yielded sufficient delineation (6.2 ± 1.4; 0.8 mSv; sensitivity=56%). CONCLUSIONS All CT scout views showed significantly better delineation ratings and sensitivity than conventional radiographs. Scout views in two planes at 80 mA provided a sufficient level of delineation and a sensitivity five times higher than conventional radiography at less than one third of the radiation dose. In case of diagnostic insecurity, CT can be performed without additional logistical effort.
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Affiliation(s)
- Edvard Ziegeler
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Nussbaumstraße 20, 80336 Munich, Germany.
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192
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Bauner KU, Biffar A, Theisen D, Greiser A, Zech CJ, Nguyen ET, Reiser MF, Wintersperger BJ. Extracellular volume fractions in chronic myocardial infarction. Invest Radiol 2012; 47:538-45. [PMID: 22836311 DOI: 10.1097/rli.0b013e3182631c37] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVES The aim of this study was to assess and delineate chronic myocardial infarction (CMI) using precontrast and postcontrast T1 mapping techniques including quantification of extracellular volume fractions (ECVs). MATERIALS AND METHODS A total of 26 patients with CMI were examined at 1.5 T applying a modified Look-Locker Inversion Recovery sequence before and 10 minutes after contrast at 3 short-axis slice positions. An inversion recovery gradient recalled echo sequence (standard of reference) was used for imaging late gadolinium enhancement. Precontrast and postcontrast T1 maps were calculated, and CMI was defined as areas with T1 values more than 3 SDs different compared with normal myocardium (MYO). T1 values of CMI, MYO, and blood pool were measured, and ECVs of CMI and MYO were calculated. Two-tailed Student t test was used for statistical analysis of T1 values and ECVs. Sensitivities and specificities for detection of CMI on precontrast and postcontrast T1 maps were calculated. Receiver operating characteristic (ROC) analysis was performed for postcontrast T1 values and ECV for discrimination of CMI. RESULTS The comparison of T1 values of CMI and MYO revealed significant differences in precontrast and postcontrast scans (1159 ± 64 vs 1001 ± 47 milliseconds, P < 0.001, and 238 ± 74 vs 379 ± 59 milliseconds, P < 0.001). Sensitivities and specificities for detection of CMI on T1 mapping were 41.7% and 100% in precontrast Look-Locker Inversion Recovery scans and 95.8% and 99.3% in postcontrast images, respectively. Average ECV for MYO and CMI were 28% ± 5% and 53% ± 10% (P < 0.001). ROC analysis revealed nonsignificantly different areas under the curve of 0.937 and 0.997 for T1 values and ECV, respectively (P = 0.137). Sensitivities and specificities were 92.3% and 92.3% for detecting CMI by postcontrast T1 values and 95.5% and 100% for ECV, with cutoff values being 305 milliseconds or less and greater than 42%. Combined criteria did not result in any further improvement of sensitivity for CMI detection. CONCLUSIONS Postcontrast T1 values and ECV of chronically infarcted MYO are significantly different compared with respective values of normal MYO. Both parameters allow for accurate detection of CMI with ECV showing marginally higher sensitivity and specificity. Precontrast T1 values lack accuracy in delineation of CMI.
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Affiliation(s)
- Kerstin Ulrike Bauner
- Department for Clinical Radiology, Grosshadern, University Hospitals, Ludwig-Maximilian-University, Munich, Germany.
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193
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Sourbron S, Sommer WH, Reiser MF, Zech CJ. Combined quantification of liver perfusion and function with dynamic gadoxetic acid-enhanced MR imaging. Radiology 2012; 263:874-83. [PMID: 22623698 DOI: 10.1148/radiol.12110337] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
PURPOSE To evaluate the feasibility of quantifying hepatic perfusion and function by using dynamic contrast material-enhanced (DCE) magnetic resonance (MR) imaging with the hepatobiliary contrast agent gadoxetic acid and a dual-inlet two-compartment uptake model. MATERIALS AND METHODS The study was approved by the local institutional review board, and written informed consent was obtained from all patients. Data were acquired between October 2008 and November 2009 in 24 patients with hepatic metastases from neuroendocrine tumors (13 men, 11 women; mean age, 59.8 years). DCE MR imaging was performed at 3.0 T with a standard dose of gadoxetic acid and a three-dimensional sequence, with 48 sections of data acquired every 2.2 seconds for 5 minutes. For each patient, a plasma flow map was calculated by means of deconvolution and the model was fitted to six region-of-interest curves. Results were evaluated with goodness-of-fit analysis and, in normal-appearing liver tissue, by comparing perfusion parameters with those reported in the literature. Interobserver effects in the selection of arterial and venous input functions were assessed. RESULTS With an arterial delay parameter, the model provided a good fit to all data. Values for arterial and venous plasma flow and extracellular volume in normal-appearing liver tissue were comparable to those in the literature. The mean intracellular uptake rate is 3.4/100/min with a standard deviation of 1.9/100/min The model also provided a good fit in all tumor data, producing high arterial flow fraction (87%) and lower uptake (1.7/100/min) . Bias due to observer-dependent differences in the selection of the input functions was negligible. CONCLUSION The analysis of dynamic gadoxetic acid-enhanced MR images with the dual-inlet two-compartment uptake model presents a new and practical approach for measuring arterial and venous perfusion and hepatic function in a single acquisition.
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Affiliation(s)
- Steven Sourbron
- Division of Medical Physics, University of Leeds, Worsley Building, Clarendon Way, Leeds LS2 9JT, England.
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194
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Abstract
CLINICAL/METHODICAL ISSUE Modern radiotherapy benefits from precise and targeted diagnostic and pretherapeutic imaging. STANDARD RADIOLOGICAL METHODS Standard imaging modalities, such as computed tomography (CT) offer high morphological detail but only limited functional information on tumors. METHODICAL INNOVATIONS Novel functional and molecular imaging modalities provide biological information about tumors in addition to detailed morphological information. PERFORMANCE Perfusion magnetic resonance imaging (MRI) CT or ultrasound-based perfusion imaging as well as hybrid modalities, such as positron emission tomography (PET) CT or MRI-PET have the potential to identify and precisely delineate viable and/or perfused tumor areas, enabling optimization of targeted radiotherapy. Functional information on tissue microcirculation and/or glucose metabolism allow a more precise definition and treatment of tumors while reducing the radiation dose and sparing the surrounding healthy tissue. ACHIEVEMENTS In the development of new imaging methods for planning individualized radiotherapy, preclinical imaging and research plays a pivotal role, as the value of multimodality imaging can only be assessed, tested and adequately developed in a preclinical setting, i.e. in animal tumor models. PRACTICAL RECOMMENDATIONS New functional imaging modalities will play an increasing role for the surveillance of early treatment response during radiation therapy and in the assessment of the potential value of new combination therapies (e.g. combining anti-angiogenic drugs with radiotherapy).
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Affiliation(s)
- K Nikolaou
- Institut für Klinische Radiologie, Klinikum der Ludwig-Maximilians-Universität, Campus Grosshadern, Marchioninistr. 15, 81377 München.
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195
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Maxien D, Ingrisch M, Meinel F, Thieme S, Reiser MF, Dietrich O, Nikolaou K. Comparison of breath-hold and free-breathing quantitative pulmonary perfusion MRI. Pneumologie 2012. [DOI: 10.1055/s-0032-1315555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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196
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Sommer WH, Becker CR, Haack M, Rubin GD, Weidenhagen R, Schwarz F, Nikolaou K, Reiser MF, Johnson TR, Clevert DA. Time-resolved CT Angiography for the Detection and Classification of Endoleaks. Radiology 2012; 263:917-26. [DOI: 10.1148/radiol.12111217] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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197
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Ashoori N, Paprottka P, Trumm C, Bamberg F, Kolligs FT, Rentsch M, Reiser MF, Jakobs TF. Multimodality treatment with conventional transcatheter arterial chemoembolization and radiofrequency ablation for unresectable hepatocellular carcinoma. Digestion 2012; 85:18-26. [PMID: 22156507 DOI: 10.1159/000334714] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 10/21/2011] [Indexed: 02/04/2023]
Abstract
BACKGROUND/AIMS To evaluate the efficacy of multimodality treatment consisting of conventional transcatheter arterial chemoembolization (TACE) and radiofrequency ablation (RFA) in patients with non-resectable and non-ablatable hepatocellular carcinoma (HCC). METHODS In this retrospective study, 85 consecutive patients with HCC (59 solitary, 29 multifocal HCC) received TACE followed by RFA between 2001 and 2010. The mean number of tumors per patient was 1.6 ± 0.7 with a mean size of 3.0 ± 0.9 cm. Both local efficacy and patient survival were evaluated. RESULTS Of 120 treated HCCs, 99 (82.5%) showed a complete response (CR), while in 21 HCCs (17.5%) a partial response was depicted. Patients with solitary HCC revealed CR in 91% (51/56); in patients with multifocal HCC (n = 29) CR was achieved in 75% (48 of 64 HCCs). The median survival for all patients was 25.5 months. The 1-, 2-, 3- and 5-year survival rates were 84.6, 58.7, 37.6 and 14.6%, respectively. Statistical analysis revealed a significant difference in survival between Barcelona Clinic Liver Cancer (BCLC) A (73.4 months) and B (50.3 months) patients, while analyses failed to show a difference for Child-Pugh score, Cancer of Liver Italian Program (CLIP) score and tumor distribution pattern. CONCLUSION TACE combined with RFA provides an effective treatment approach with high local tumor control rates and promising survival data, especially for BCLC A patients. Randomized trials are needed to compare this multimodality approach with a single modality approach for early-stage HCC.
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Affiliation(s)
- N Ashoori
- Department of Radiology, Ludwig Maximilians University of Munich, Campus Grosshadern, Munich, Germany.
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198
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Clevert DA, Helck A, Paprottka PM, Zengel P, Trumm C, Reiser MF. [Ultrasound-guided image fusion with computed tomography and magnetic resonance imaging. Clinical utility for imaging and interventional diagnostics of hepatic lesions]. Radiologe 2012; 52:63-9. [PMID: 22249703 DOI: 10.1007/s00117-011-2252-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Abdominal ultrasound is often the first-line imaging modality for assessing focal liver lesions. Due to various new ultrasound techniques, such as image fusion, global positioning system (GPS) tracking and needle tracking guided biopsy, abdominal ultrasound now has great potential regarding detection, characterization and treatment of focal liver lesions. Furthermore, these new techniques will help to improve the clinical management of patients before and during interventional procedures. This article presents the principle and clinical impact of recently developed techniques in the field of ultrasound, e.g. image fusion, GPS tracking and needle tracking guided biopsy and discusses the results based on a feasibility study on 20 patients with focal hepatic lesions.
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Affiliation(s)
- D-A Clevert
- Institut für Klinische Radiologie, Klinikum der Ludwig-Maximilians-Universität, Campus Grosshadern, Marchioninistr. 15, 81377, München, Deutschland.
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199
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Thieme SF, Möller W, Becker S, Schuschnig U, Eickelberg O, Helck AD, Reiser MF, Johnson TRC. Ventilation imaging of the paranasal sinuses using xenon-enhanced dynamic single-energy CT and dual-energy CT: a feasibility study in a nasal cast. Eur Radiol 2012; 22:2110-6. [PMID: 22610534 DOI: 10.1007/s00330-012-2483-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2012] [Revised: 03/21/2012] [Accepted: 03/27/2012] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To show the feasibility of dual-energy CT (DECT) and dynamic CT for ventilation imaging of the paranasal sinuses in a nasal cast. METHODS In a first trial, xenon gas was administered to a nasal cast with a laminar flow of 7 L/min. Dynamic CT acquisitions of the nasal cavity and the sinuses were performed. This procedure was repeated with pulsating xenon flow. Local xenon concentrations in the different compartments of the model were determined on the basis of the enhancement levels. In a second trial, DECT measurements were performed both during laminar and pulsating xenon administration and the xenon concentrations were quantified directly. RESULTS Neither with dynamic CT nor DECT could xenon-related enhancement be detected in the sinuses during laminar airflow. Using pulsating flow, dynamic imaging showed a xenon wash-in and wash-out in the sinuses that followed a mono-exponential function with time constants of a few seconds. Accordingly, DECT revealed xenon enhancement in the sinuses only after pulsating xenon administration. CONCLUSION The feasibility of xenon-enhanced DECT for ventilation imaging was proven in a nasal cast. The superiority of pulsating gas flow for the administration of gas or aerosolised drugs to the paranasal sinuses was demonstrated. KEY POINTS • Ventilation of the paranasal sinuses is poorly understood. • Dual-energy CT ventilation imaging has been explored using phantom simulation. • Xenon can be seen in the paranasal sinuses using pulsating xenon flow. • Dual-energy CT uses a lower radiation dose compared with dynamic ventilation CT.
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Affiliation(s)
- Sven F Thieme
- Institute for Clinical Radiology, Ludwig Maximilians University Hospital Munich, Klinikum Großhadern, Marchioninistr. 15, 81377, Munich, Germany.
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200
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D'Anastasi M, Schneevoigt BS, Trottmann M, Crispin A, Stief C, Reiser MF, Clevert DA. Acoustic radiation force impulse imaging of the testes: a preliminary experience. Clin Hemorheol Microcirc 2012; 49:105-14. [PMID: 22214682 DOI: 10.3233/ch-2011-1461] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE Acoustic radiation force impulse imaging (ARFI) is a newly developed technique for the sonographic quantification of tissue elasticity. It has been used in the assessment of various abdominal organs. The testes are extraabdominal organs with limited overlying tissue, making them ideally suited to ARFI assessment. To our knowledge no published data exist on ARFI elastography of the testes. METHOD 23 male volunteers (mean age 45.13 ± 17.3, range 23-75) with no known testicular pathology underwent normal B-mode sonography with ARFI elastometry of both testes using a Siemens Acuson S2000™ (Siemens Healthcare, Germany) system. 15 measurements were performed on each testis; 5 each in the upper pole, middle portion and lower pole. Results were statistically evaluated. RESULTS 95% of the SWV values were found to lie within the reference interval ranging from 0.62 to 1.01 m/s. There was a significant association between measured SWV and age (P = 0.0056) and testicular volume (P = 0.0003). CONCLUSION ARFI elastometry proved to be feasible in the assessment of testicular stiffness. Older age and lower testicular volumes were associated with increased parenchymal stiffness. Further studies with more subjects may be required to define the normal range of values for each age group.
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Affiliation(s)
- M D'Anastasi
- Institute of Clinical Radiology, University of Munich-Grosshadern Campus, Munich, Germany.
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