M Meyer

Publications of M Meyer

• [A training program for dementia trainers : Does this program have practical relevance?]

  Authors: H Schulz, S Auer, E Span, C Adler, Y Donabauer, S Weber, J Wimmer-Elias, M Meyer

  Zeitschrift fur Gerontologie und Geriatrie. 04/2012;

  BACKGROUND: Specific curricula for professionals working in various settings with persons with dementia have been developed and implemented into practice. In this study, the practical relevance of aBACKGROUND: Specific curricula for professionals working in various settings with persons with dementia have been developed and implemented into practice. In this study, the practical relevance of a teaching program for the M.A.S (Morbus Alzheimer syndrome) dementia trainer was evaluated. The curriculum was developed in 2002 within a scientific project. The goal was that care professionals and noncare professionals learn how to support and train persons with dementia and their caregivers. The task of the trainer is to support the functional and emotional resources of the person with dementia employing stage-specific training according to principles of the theory of retrogenesis. Trainers are also able to support family caregivers in their difficult day-to-day care for the person with dementia. With this training and support program, persons with dementia can train their residual capacities and develop a life perspective which enables them to cope with the long duration of Alzheimer's disease. MATERIALS AND METHODS: The curriculum for the training methodology is based in the theory of retrogenesis. The 1-year training course is held in the form of modules and includes the following topics: (1) stages of dementia and medical aspects, (2) communication with persons with dementia, (3) stage-specific retrogenic training, (4) physical training for the elderly and persons with dementia, (5) coaching family caregivers through the long disease duration, and (6) care issues for persons without education in care. M.A.S trainers were questioned after they had concluded the teaching program successfully and had the chance to apply the content of the teaching program in their practical work. A short questionnaire was sent via e-mail or a telephone interview was performed. RESULTS: A total of 279 trainers graduated and were certified. Of these, 140 persons (53.6% of the population) could be questioned after an average of 2.69 years after completion of the course: 93.6% of trainees were still using the principles of the teaching course successfully; of these, 56% were working in the function of a trainer full time and 44% used the principles within their work environment (mainly in the nursing home environment). CONCLUSION: The study found that the majority of questioned trainers are still using the principles taught in the course successfully with persons with dementia living at home and the content was found to be relevant for practice. The content of the teaching course, applying principles of retrogenesis, which was originally designed for persons with dementia living at home, can also be successfully applied in the nursing home environment. Increasing interest has been shown by institutions employing professionals whose task it is to keep persons with dementia active and interested as well as physically functioning at their best possible level. As a consequence, persons with dementia perceive higher quality of life and exhibit fewer behavior problems which complicate care. More research is needed to accumulate evidence and to support these findings.

• Pulmonary embolism: ct signs and cardiac biomarkers for predicting right ventricular dysfunction.

  Authors: T Henzler, S Roeger, M Meyer, U J Schoepf, J W Nance, D Haghi, W E Kaminski, M Neumaier, S O Schoenberg, C Fink

  The European respiratory journal : official journal of the European Society for Clinical Respiratory Physiology. 09/2011;

  To prospectively evaluate the accuracy of quantitative cardiac CT parameters and two cardiac biomarkers (NT-pro-Brain Natriuretic Peptide (NT-pro-BNP); troponin I), alone and in combination, forTo prospectively evaluate the accuracy of quantitative cardiac CT parameters and two cardiac biomarkers (NT-pro-Brain Natriuretic Peptide (NT-pro-BNP); troponin I), alone and in combination, for predicting right ventricular dysfunction (RVD) in patients with acute pulmonary embolism (PE).557 consecutive patients with suspected PE underwent pulmonary CTA. Patients with PE also underwent echocardiography and NT-pro-BNP/troponin I serum level measurements. 3 different CT measurements were obtained (RV/LVaxial, RV/LV4-CH), and RV/LVvolume). CT measurements and NT-pro-BNP/troponin I serum levels were correlated with RVD at echocardiography.Patients with RVD (n=77) showed significantly higher RV/LV ratios and NT-pro-BNP/troponin I levels compared to those without RVD (RV/LVaxial 1.68±0.84 vs. 1.00±0.21; RV/LV4ch 1.52±0.45 vs. 1.01±0.21; RV/LVvolume 1.97±0.53 vs. 1.07±0.52; serum NT-pro-BNP 6372±2319 vs. 1032±1559 ng·L(-1); troponin I 0.18±0.41 vs. 0.06±0.18). The area under the curve for the detection of RVD of RV/LVaxial, RV/LV4Ch, RV/LVvolume, NT-pro-BNP and troponin I were 0.84, 0.87, 0.93, 0.83 and 0.70 respectively. The combination of biomarkers and RV/LVvolume increased the AUC to 0.95 (RV/LVvolume with NT-pro-BNP) and 0.93 (RV/LVvolume with troponin I).RV/LVvolume is the most accurate CT parameter for identifying patients with RVD. A combination of RV/LVvolume with NT-pro-BNP or troponin I measurements improves the diagnostic accuracy of either test alone.

• Correlation of CT angiographic pulmonary artery obstruction scores with right ventricular dysfunction and clinical outcome in patients with acute pulmonary embolism.

  Authors: P Apfaltrer, T Henzler, M Meyer, S Roeger, D Haghi, J Gruettner, T Süselbeck, R B Wilson, U J Schoepf, S O Schoenberg, C Fink

  European journal of radiology. 09/2011;

  OBJECTIVE: To correlate CTA pulmonary artery obstruction scores (OS) with right ventricular dysfunction (RVD) and clinical outcome in patients with acute pulmonary embolism (PE). MATERIALS ANDOBJECTIVE: To correlate CTA pulmonary artery obstruction scores (OS) with right ventricular dysfunction (RVD) and clinical outcome in patients with acute pulmonary embolism (PE). MATERIALS AND METHODS: In a prospective study of 50 patients (66±12.9 years) with PE pulmonary artery OS (Qanadli, Mastora, and Mastora central) were assessed by two radiologists. To assess RVD all patients underwent echocardiography within 24h. Furthermore, RVD on CT was assessed by calculating the right ventricular/left ventricular (RV/LV) diameter ratios on transverse (RV/LVtrans) and four-chamber views (RV/LV4ch) as well as the RV/LV volume ratio (RV/LVvol). OS were correlated with RVD and the occurrence of adverse clinical outcomes (defined as death, need for intensive care treatment, or cardiac insufficiency ≥NYHA III). RESULTS: Mean Mastora, Qanadli, and Mastora central OS were 26.4±17.7, 12.6±9.9 and 7.5±9, respectively. Echocardiography demonstrated moderate and severe RVD in 10 and 5 patients, respectively. Patients with moderate and severe RVD showed significantly higher Mastora central scores than patients without RVD (14±10.8 vs. 5.9±7.8 [p=0.05]; 17.6±13.2 vs. 5.9±7.8 [p=0.038]). A relevant correlation (i.e. r≥0.6) between OS and CT parameters for RVD were only found for the Mastora score and the Mastora central score (RV/LV4ch: r=0.61 and 0.68, RV/LVvol: r=0.61 and 0.6). 18 patients experienced an adverse clinical outcome. None of the OS differed significantly between patients with and without adverse clinical outcome. CONCLUSION: Pulmonary artery obstruction scores can differentiate between patients with and without RVD. However, in this study, obstruction scores were not correlated to adverse clinical outcome.

• Functional imaging of lung cancer using dual energy CT: how does iodine related attenuation correlate with standardized uptake value of 18FDG-PET-CT?

  Authors: G Schmid-Bindert, Thomas Henzler, T Q Chu, M Meyer, J W Nance, U J Schoepf, D J Dinter, P Apfaltrer, R Krissak, C Manegold, S O Schoenberg, C Fink

  European radiology. 08/2011; 22(1):93-103.

  To investigate the correlation between maximum standardized uptake value (SUV(max)) of (18)FDG PET-CT and iodine-related attenuation (IRA) of dual energy CT (DECT) of primary tumours and (18)FDGTo investigate the correlation between maximum standardized uptake value (SUV(max)) of (18)FDG PET-CT and iodine-related attenuation (IRA) of dual energy CT (DECT) of primary tumours and (18)FDG PET-CT positive thoracic lymph nodes (LN) in patients with lung cancer. 37 patients with lung cancer (27 NSCLC, 10 SCLC, 86 (18)FDG PET-CT positive thoracic LN) who underwent both (18)FDG PET-CT and DECT were analyzed. The mean study interval between (18)FDG PET-CT and DECT was ≤21 days in 17 patients. The mean and maximum IRA of DECT as well as of virtual unenhanced and virtual 120 kV images of DECT was analyzed and correlated to the SUV(max) of (18)FDG PET-CT in all tumours and (18)FDG PET-CT positive thoracic lymph nodes. Further subgroup analysis was performed for histological subtypes in all groups. A moderate correlation was found between SUV(max) and maximum IRA in all tumours (n = 37;r = 0.507;p = 0.025) whereas only weak or no correlation were found between SUV(max) and all other DECT measurements. A strong correlation was found in patients with study intervals ≤21 days (n = 17; r = 0.768;p = 0.017). Analysis of histological subtypes of lung cancer showed a strong correlation between SUV(max) and maximum IRA in the analysis of all patients with NSCLC (r = 0.785;p = 0.001) and in patients with NSCLC and study intervals ≤21 days (r = 0.876;p = 0.024). Thoracic LN showed moderate correlation between SUV(max) and maximum IRA in patients with study intervals ≤21 days (r = 0.654; p = 0.010) whereas a weak correlation was found between SUV(max) and maximum IRA in patients with study intervals >21 days (r = 0.299; p = 0.035). DECT could serve as a valuable functional imaging test for patients with NSCLC as the IRA of DECT correlates with SUV(max) of (18)FDG PET-CT.

• Correlation of CT angiographic pulmonary artery obstruction scores with right ventricular dysfunction and clinical outcome in patients with acute pulmonary embolism

  Authors: P. Apfaltrer, T. Henzler, M. Meyer, S. Roeger, D. Haghi, J. Gruettner, T. Suselbeck, R. B. Wilson, U. J. Schoepf, S. O. Schoenberg, C. Fink

  Eur J Radiol.

  OBJECTIVE: To correlate CTA pulmonary artery obstruction scores (OS) with right ventricular dysfunction (RVD) and clinical outcome in patients with acute pulmonary embolism (PE). MATERIALS ANDOBJECTIVE: To correlate CTA pulmonary artery obstruction scores (OS) with right ventricular dysfunction (RVD) and clinical outcome in patients with acute pulmonary embolism (PE). MATERIALS AND METHODS: In a prospective study of 50 patients (66+/-12.9 years) with PE pulmonary artery OS (Qanadli, Mastora, and Mastora central) were assessed by two radiologists. To assess RVD all patients underwent echocardiography within 24h. Furthermore, RVD on CT was assessed by calculating the right ventricular/left ventricular (RV/LV) diameter ratios on transverse (RV/LVtrans) and four-chamber views (RV/LV4ch) as well as the RV/LV volume ratio (RV/LVvol). OS were correlated with RVD and the occurrence of adverse clinical outcomes (defined as death, need for intensive care treatment, or cardiac insufficiency >/=NYHA III). RESULTS: Mean Mastora, Qanadli, and Mastora central OS were 26.4+/-17.7, 12.6+/-9.9 and 7.5+/-9, respectively. Echocardiography demonstrated moderate and severe RVD in 10 and 5 patients, respectively. Patients with moderate and severe RVD showed significantly higher Mastora central scores than patients without RVD (14+/-10.8 vs. 5.9+/-7.8 [p=0.05]; 17.6+/-13.2 vs. 5.9+/-7.8 [p=0.038]). A relevant correlation (i.e. r>/=0.6) between OS and CT parameters for RVD were only found for the Mastora score and the Mastora central score (RV/LV4ch: r=0.61 and 0.68, RV/LVvol: r=0.61 and 0.6). 18 patients experienced an adverse clinical outcome. None of the OS differed significantly between patients with and without adverse clinical outcome. CONCLUSION: Pulmonary artery obstruction scores can differentiate between patients with and without RVD. However, in this study, obstruction scores were not correlated to adverse clinical outcome.

• Contrast-enhanced dual-energy CT of gastrointestinal stromal tumors: is iodine-related attenuation a potential indicator of tumor response?

  Authors: P. Apfaltrer, M. Meyer, C. Meier, T. Henzler, J. M. Barraza, D. J. Dinter, P. Hohenberger, U. J. Schoepf, S. O. Schoenberg, C. Fink

  Invest Radiol. 47(1):65-70.

  OBJECTIVES: To assess the correlation of true nonenhanced (TNE) and virtually nonenhanced (VNE) images of abdominal dual-energy computed tomography (DECT) in patients with metastatic gastrointestinalOBJECTIVES: To assess the correlation of true nonenhanced (TNE) and virtually nonenhanced (VNE) images of abdominal dual-energy computed tomography (DECT) in patients with metastatic gastrointestinal stromal tumors (GIST), and further to investigate the correlation of iodine-related attenuation (IRA) of DECT with the Choi criteria. MATERIAL AND METHODS: Twenty-four consecutive patients (5 women aged 61 +/- 10 years) with metastatic GIST underwent DECT of the abdomen (80 kV, 140 kV) using first-generation dual-source computed tomography (CT). All patients had at least one or more liver lesions (median, 4; maximum, 9). Image data were processed with a dedicated DECT software algorithm designed for evaluation of iodine distribution in soft tissue lesions, and VNE CT images were generated. The tumor density (according to Choi criteria) and the maximum transverse diameter of the lesions (according to Response Evaluation Criteria in Solid Tumors [RECIST]) were determined. TNE and VNE lesion attenuation and Choi criteria and IRA were correlated with each other. RESULTS: A total of 291 liver lesions were evaluated, of which 220 were cystic and 71 were solid. The mean lesion size was 4.5 +/- 3.2 cm (1.1-18.7 cm). The mean attenuation of all lesions was significantly higher in the TNE images than in the VNE images (P=0.0001). Pearson statistics revealed an excellent correlation of r=0.843 (P=0.0001) between IRA and Choi criteria for all lesions. DECT showed significantly higher IRA in progressive (23.3 +/- 9.5 HU) lesions compared with stable or regressive (17.8 +/- 9.1 HU) lesions (P=0.0185). Similarly, the Choi criteria differed significantly between progressive (39.9 +/- 12.8 HU) and stable/regressive (31.1 +/- 10.3 HU) lesions (P=0.0003). CONCLUSIONS: DECT is a promising imaging method for the assessment of treatment response in GIST, as IRA might be a more robust response parameter than the Choi criteria. VNE CT data calculated from DECT may eliminate the need for acquisition of a separate unenhanced data set.

• Image findings of patients with H1N1 virus pneumonia and acute respiratory failure

  Authors: T. Henzler, M. Meyer, A. Kalenka, M. Alb, G. Schmid-Bindert, S. Bartling, J. U. Schoepf, S. O. Schoenberg, C. Fink

  Acad Radiol. 17(6):681-5.

  RATIONALE AND OBJECTIVES: The aim of this study was to assess the findings of chest radiography and high-resolution computed tomography in patients requiring intensive care unit treatment for severeRATIONALE AND OBJECTIVES: The aim of this study was to assess the findings of chest radiography and high-resolution computed tomography in patients requiring intensive care unit treatment for severe H1N1 virus pneumonia. MATERIALS AND METHODS: In 2009, 10 patients required treatment in an intensive care unit for confirmed H1N1 pneumonia. All patients underwent chest radiography and high-resolution computed tomography. All 10 patients required mechanical ventilation because of respiratory failure. Nine patients presented with severe acute respiratory distress syndrome, and one patient died. Four patients underwent extracorporeal membrane oxygenation (ECMO) therapy. The results of chest radiography and high-resolution computed tomographic scans of these patients were systematically analyzed. RESULTS: The mean age of all patients was 44.1 +/- 12.3 years. All 10 patients showed abnormal results on chest radiography. The radiographic abnormalities were bilateral and multifocal in 10 patients. The predominant radiographic findings were consolidations (n = 9), ground-glass opacities (n = 8), and reticular opacities (n = 2). The most frequent computed tomographic findings at presentation consisted of bilateral ground-glass opacities (n = 9), pleural effusion (n = 9), areas of consolidation (n = 8), interstitial marking (n = 8), and crazy paving (n = 4). All patients undergoing ECMO therapy showed extensive bilateral ground-glass opacities, multifocal areas of consolidation, and crazy paving. Pleural effusion was present in three of four patients undergoing ECMO therapy. CONCLUSION: Patients requiring treatment in an intensive care unit for severe H1N1 pneumonia are at high risk for developing acute respiratory distress syndrome and frequently require ECMO therapy.

• Attenuation-based characterization of coronary atherosclerotic plaque: comparison of dual source and dual energy CT with single-source CT and histopathology

  Authors: T. Henzler, S. Porubsky, H. Kayed, N. Harder, U. R. Krissak, M. Meyer, T. Sueselbeck, A. Marx, H. Michaely, U. J. Schoepf, S. O. Schoenberg, C. Fink

  Eur J Radiol. 80(1):54-9.

  OBJECTIVE: To compare different CT acquisition techniques regarding for attenuation-based characterization of coronary atherosclerotic plaques using histopathology as the standard of reference.OBJECTIVE: To compare different CT acquisition techniques regarding for attenuation-based characterization of coronary atherosclerotic plaques using histopathology as the standard of reference. MATERIALS AND METHODS: In a post mortem study 17 human hearts were studied with dual-source CT (DSCT) and dual energy CT (DECT) mode on a DSCT as well as with 16-slice single-source CT (SSCT). At autopsy, atherosclerotic lesions were cut at 5 mum sections. Histopathologic classification of the plaques according to the American Heart Association (AHA) criteria was performed by two pathologists. Attenuation values of all plaques were measured in DSCT, DECT and SSCT studies, respectively and classified based on attenuation according to modified AHA criteria. RESULTS: 58 coronary plaques were identified at autopsy. Regardless of the CT technique only 52/58 plaques were found at CT (sensitivity=89.6%). There was no significant difference between the mean attenuation values of different plaque types between DSCT, DECT, and SSCT: type IV: 11HU/8HU/19HU; type Va: 44HU/45HU/52HU; type Vb: 1088HU/966HU/1079HU). The sensitivity for correct classification varied depending on the plaque type (type II=0%, type III=0%, type IV=43%, type Va=58%, Vb=97%). CONCLUSION: Independent of the used acquisition technique, SSCT, DSCT and DECT show similar results for attenuation-based characterization of atherosclerotic coronary plaques.

• Pulmonary embolism: CT signs and cardiac biomarkers for predicting right ventricular dysfunction

  Authors: T. Henzler, S. Roeger, M. Meyer, U. J. Schoepf, J. W. Nance, D. Haghi, W. E. Kaminski, M. Neumaier, S. O. Schoenberg, C. Fink

  Eur Respir J. 39(4):919-26.

  The aim of this study was to prospectively evaluate the accuracy of quantitative cardiac computed tomography (CT) parameters and two cardiac biomarkers (N-terminal-pro-brain natriuretic peptideThe aim of this study was to prospectively evaluate the accuracy of quantitative cardiac computed tomography (CT) parameters and two cardiac biomarkers (N-terminal-pro-brain natriuretic peptide (NT-pro-BNP) and troponin I), alone and in combination, for predicting right ventricular dysfunction (RVD) in patients with acute pulmonary embolism. 557 consecutive patients with suspected pulmonary embolism underwent pulmonary CT angiography. Patients with pulmonary embolism also underwent echocardiography and NT-pro-BNP/troponin I serum level measurements. Three different CT measurements were obtained (right ventricular (RV)/left ventricular (LV)(axial), RV/LV(4-CH) and RV/LV(volume)). CT measurements and NT-pro-BNP/troponin I serum levels were correlated with RVD at echocardiography. 77 patients with RVD showed significantly higher RV/LV ratios and NT-pro-BNP/troponin I levels compared to those without RVD (RV/LV(axial) 1.68+/-0.84 versus 1.00+/-0.21; RV/LV(4-CH) 1.52+/-0.45 versus 1.01+/-0.21; RV/LV(volume) 1.97+/-0.53 versus 1.07+/-0.52; serum NT-pro-BNP 6,372+/-2,319 versus 1,032+/-1,559 ng.L(-1); troponin I 0.18+/-0.41 versus 0.06+/-0.18 g.L(-1)). The area under the curve for the detection of RVD of RV/LV(axial), RV/LV(4-CH), RV/LV(volume), NT-pro-BNP and troponin I were 0.84, 0.87, 0.93, 0.83 and 0.70 respectively. The combination of biomarkers and RV/LV(volume) increased the AUC to 0.95 (RV/LV(volume) with NT-pro-BNP) and 0.93 (RV/LV(volume) with troponin I). RV/LV(volume) is the most accurate CT parameter for identifying patients with RVD. A combination of RV/LV(volume) with NT-pro-BNP or troponin I measurements improves the diagnostic accuracy of either test alone.

• Quantification of left and right ventricular function and myocardial mass: Comparison of low-radiation dose 2nd generation dual-source CT and cardiac MRI

  Authors: R. A. Takx, A. Moscariello, U. J. Schoepf, J. M. Barraza, J. W. Nance, G. Bastarrika, M. Das, M. Meyer, J. E. Wildberger, S. O. Schoenberg, C. Fink, T. Henzler

  Eur J Radiol. 81(4):e598-604.

  OBJECTIVE: To prospectively evaluate the accuracy of left and right ventricular function and myocardial mass measurements based on a dual-step, low radiation dose protocol with prospectivelyOBJECTIVE: To prospectively evaluate the accuracy of left and right ventricular function and myocardial mass measurements based on a dual-step, low radiation dose protocol with prospectively ECG-triggered 2nd generation dual-source CT (DSCT), using cardiac MRI (cMRI) as the reference standard. MATERIALS AND METHODS: Twenty patients underwent 1.5T cMRI and prospectively ECG-triggered dual-step pulsing cardiac DSCT. This image acquisition mode performs low-radiation (20% tube current) imaging over the majority of the cardiac cycle and applies full radiation only during a single adjustable phase. Full-radiation-phase images were used to assess cardiac morphology, while low-radiation-phase images were used to measure left and right ventricular function and mass. Quantitative CT measurements based on contiguous multiphase short-axis reconstructions from the axial CT data were compared with short-axis SSFP cardiac cine MRI. Contours were manually traced around the ventricular borders for calculation of left and right ventricular end-diastolic volume, end-systolic volume, stroke volume, ejection fraction and myocardial mass for both modalities. Statistical methods included independent t-tests, the Mann-Whitney U test, Pearson correlation statistics, and Bland-Altman analysis. RESULTS: All CT measurements of left and right ventricular function and mass correlated well with those from cMRI: for left/right end-diastolic volume r=0.885/0.801, left/right end-systolic volume r=0.947/0.879, left/right stroke volume r=0.620/0.697, left/right ejection fraction r=0.869/0.751, and left/right myocardial mass r=0.959/0.702. Mean radiation dose was 6.2+/-1.8mSv. CONCLUSIONS: Prospectively ECG-triggered, dual-step pulsing cardiac DSCT accurately quantifies left and right ventricular function and myocardial mass in comparison with cMRI with substantially lower radiation exposure than reported for traditional retrospective ECG-gating.

• Attenuation-based characterization of coronary atherosclerotic plaque: comparison of dual source and dual energy CT with single-source CT and histopathology

  Authors: T. Henzler, S. Porubsky, H. Kayed, N. Harder, U. R. Krissak, M. Meyer, T. Sueselbeck, A. Marx, H. Michaely, U. J. Schoepf, S. O. Schoenberg, C. Fink

  Eur J Radiol. 80(1):54-9.

  OBJECTIVE: To compare different CT acquisition techniques regarding for attenuation-based characterization of coronary atherosclerotic plaques using histopathology as the standard of reference.OBJECTIVE: To compare different CT acquisition techniques regarding for attenuation-based characterization of coronary atherosclerotic plaques using histopathology as the standard of reference. MATERIALS AND METHODS: In a post mortem study 17 human hearts were studied with dual-source CT (DSCT) and dual energy CT (DECT) mode on a DSCT as well as with 16-slice single-source CT (SSCT). At autopsy, atherosclerotic lesions were cut at 5 mum sections. Histopathologic classification of the plaques according to the American Heart Association (AHA) criteria was performed by two pathologists. Attenuation values of all plaques were measured in DSCT, DECT and SSCT studies, respectively and classified based on attenuation according to modified AHA criteria. RESULTS: 58 coronary plaques were identified at autopsy. Regardless of the CT technique only 52/58 plaques were found at CT (sensitivity=89.6%). There was no significant difference between the mean attenuation values of different plaque types between DSCT, DECT, and SSCT: type IV: 11HU/8HU/19HU; type Va: 44HU/45HU/52HU; type Vb: 1088HU/966HU/1079HU). The sensitivity for correct classification varied depending on the plaque type (type II=0%, type III=0%, type IV=43%, type Va=58%, Vb=97%). CONCLUSION: Independent of the used acquisition technique, SSCT, DSCT and DECT show similar results for attenuation-based characterization of atherosclerotic coronary plaques.

• Quantification of left and right ventricular function and myocardial mass: Comparison of low-radiation dose 2nd generation dual-source CT and cardiac MRI

  Authors: R. A. Takx, A. Moscariello, U. J. Schoepf, J. M. Barraza, J. W. Nance, G. Bastarrika, M. Das, M. Meyer, J. E. Wildberger, S. O. Schoenberg, C. Fink, T. Henzler

  Eur J Radiol. 81(4):e598-604.

  OBJECTIVE: To prospectively evaluate the accuracy of left and right ventricular function and myocardial mass measurements based on a dual-step, low radiation dose protocol with prospectivelyOBJECTIVE: To prospectively evaluate the accuracy of left and right ventricular function and myocardial mass measurements based on a dual-step, low radiation dose protocol with prospectively ECG-triggered 2nd generation dual-source CT (DSCT), using cardiac MRI (cMRI) as the reference standard. MATERIALS AND METHODS: Twenty patients underwent 1.5T cMRI and prospectively ECG-triggered dual-step pulsing cardiac DSCT. This image acquisition mode performs low-radiation (20% tube current) imaging over the majority of the cardiac cycle and applies full radiation only during a single adjustable phase. Full-radiation-phase images were used to assess cardiac morphology, while low-radiation-phase images were used to measure left and right ventricular function and mass. Quantitative CT measurements based on contiguous multiphase short-axis reconstructions from the axial CT data were compared with short-axis SSFP cardiac cine MRI. Contours were manually traced around the ventricular borders for calculation of left and right ventricular end-diastolic volume, end-systolic volume, stroke volume, ejection fraction and myocardial mass for both modalities. Statistical methods included independent t-tests, the Mann-Whitney U test, Pearson correlation statistics, and Bland-Altman analysis. RESULTS: All CT measurements of left and right ventricular function and mass correlated well with those from cMRI: for left/right end-diastolic volume r=0.885/0.801, left/right end-systolic volume r=0.947/0.879, left/right stroke volume r=0.620/0.697, left/right ejection fraction r=0.869/0.751, and left/right myocardial mass r=0.959/0.702. Mean radiation dose was 6.2+/-1.8mSv. CONCLUSIONS: Prospectively ECG-triggered, dual-step pulsing cardiac DSCT accurately quantifies left and right ventricular function and myocardial mass in comparison with cMRI with substantially lower radiation exposure than reported for traditional retrospective ECG-gating.

• Contrast-enhanced dual-energy CT of gastrointestinal stromal tumors: is iodine-related attenuation a potential indicator of tumor response?

  Authors: P. Apfaltrer, M. Meyer, C. Meier, T. Henzler, J. M. Barraza, D. J. Dinter, P. Hohenberger, U. J. Schoepf, S. O. Schoenberg, C. Fink

  Invest Radiol. 47(1):65-70.

  OBJECTIVES: To assess the correlation of true nonenhanced (TNE) and virtually nonenhanced (VNE) images of abdominal dual-energy computed tomography (DECT) in patients with metastatic gastrointestinalOBJECTIVES: To assess the correlation of true nonenhanced (TNE) and virtually nonenhanced (VNE) images of abdominal dual-energy computed tomography (DECT) in patients with metastatic gastrointestinal stromal tumors (GIST), and further to investigate the correlation of iodine-related attenuation (IRA) of DECT with the Choi criteria. MATERIAL AND METHODS: Twenty-four consecutive patients (5 women aged 61 +/- 10 years) with metastatic GIST underwent DECT of the abdomen (80 kV, 140 kV) using first-generation dual-source computed tomography (CT). All patients had at least one or more liver lesions (median, 4; maximum, 9). Image data were processed with a dedicated DECT software algorithm designed for evaluation of iodine distribution in soft tissue lesions, and VNE CT images were generated. The tumor density (according to Choi criteria) and the maximum transverse diameter of the lesions (according to Response Evaluation Criteria in Solid Tumors [RECIST]) were determined. TNE and VNE lesion attenuation and Choi criteria and IRA were correlated with each other. RESULTS: A total of 291 liver lesions were evaluated, of which 220 were cystic and 71 were solid. The mean lesion size was 4.5 +/- 3.2 cm (1.1-18.7 cm). The mean attenuation of all lesions was significantly higher in the TNE images than in the VNE images (P=0.0001). Pearson statistics revealed an excellent correlation of r=0.843 (P=0.0001) between IRA and Choi criteria for all lesions. DECT showed significantly higher IRA in progressive (23.3 +/- 9.5 HU) lesions compared with stable or regressive (17.8 +/- 9.1 HU) lesions (P=0.0185). Similarly, the Choi criteria differed significantly between progressive (39.9 +/- 12.8 HU) and stable/regressive (31.1 +/- 10.3 HU) lesions (P=0.0003). CONCLUSIONS: DECT is a promising imaging method for the assessment of treatment response in GIST, as IRA might be a more robust response parameter than the Choi criteria. VNE CT data calculated from DECT may eliminate the need for acquisition of a separate unenhanced data set.

• Correlation of CT angiographic pulmonary artery obstruction scores with right ventricular dysfunction and clinical outcome in patients with acute pulmonary embolism

  Authors: P. Apfaltrer, T. Henzler, M. Meyer, S. Roeger, D. Haghi, J. Gruettner, T. Suselbeck, R. B. Wilson, U. J. Schoepf, S. O. Schoenberg, C. Fink

  Eur J Radiol.

  OBJECTIVE: To correlate CTA pulmonary artery obstruction scores (OS) with right ventricular dysfunction (RVD) and clinical outcome in patients with acute pulmonary embolism (PE). MATERIALS ANDOBJECTIVE: To correlate CTA pulmonary artery obstruction scores (OS) with right ventricular dysfunction (RVD) and clinical outcome in patients with acute pulmonary embolism (PE). MATERIALS AND METHODS: In a prospective study of 50 patients (66+/-12.9 years) with PE pulmonary artery OS (Qanadli, Mastora, and Mastora central) were assessed by two radiologists. To assess RVD all patients underwent echocardiography within 24h. Furthermore, RVD on CT was assessed by calculating the right ventricular/left ventricular (RV/LV) diameter ratios on transverse (RV/LVtrans) and four-chamber views (RV/LV4ch) as well as the RV/LV volume ratio (RV/LVvol). OS were correlated with RVD and the occurrence of adverse clinical outcomes (defined as death, need for intensive care treatment, or cardiac insufficiency >/=NYHA III). RESULTS: Mean Mastora, Qanadli, and Mastora central OS were 26.4+/-17.7, 12.6+/-9.9 and 7.5+/-9, respectively. Echocardiography demonstrated moderate and severe RVD in 10 and 5 patients, respectively. Patients with moderate and severe RVD showed significantly higher Mastora central scores than patients without RVD (14+/-10.8 vs. 5.9+/-7.8 [p=0.05]; 17.6+/-13.2 vs. 5.9+/-7.8 [p=0.038]). A relevant correlation (i.e. r>/=0.6) between OS and CT parameters for RVD were only found for the Mastora score and the Mastora central score (RV/LV4ch: r=0.61 and 0.68, RV/LVvol: r=0.61 and 0.6). 18 patients experienced an adverse clinical outcome. None of the OS differed significantly between patients with and without adverse clinical outcome. CONCLUSION: Pulmonary artery obstruction scores can differentiate between patients with and without RVD. However, in this study, obstruction scores were not correlated to adverse clinical outcome.

• Pulmonary embolism: CT signs and cardiac biomarkers for predicting right ventricular dysfunction

  Authors: T. Henzler, S. Roeger, M. Meyer, U. J. Schoepf, J. W. Nance, D. Haghi, W. E. Kaminski, M. Neumaier, S. O. Schoenberg, C. Fink

  Eur Respir J. 39(4):919-26.

  The aim of this study was to prospectively evaluate the accuracy of quantitative cardiac computed tomography (CT) parameters and two cardiac biomarkers (N-terminal-pro-brain natriuretic peptideThe aim of this study was to prospectively evaluate the accuracy of quantitative cardiac computed tomography (CT) parameters and two cardiac biomarkers (N-terminal-pro-brain natriuretic peptide (NT-pro-BNP) and troponin I), alone and in combination, for predicting right ventricular dysfunction (RVD) in patients with acute pulmonary embolism. 557 consecutive patients with suspected pulmonary embolism underwent pulmonary CT angiography. Patients with pulmonary embolism also underwent echocardiography and NT-pro-BNP/troponin I serum level measurements. Three different CT measurements were obtained (right ventricular (RV)/left ventricular (LV)(axial), RV/LV(4-CH) and RV/LV(volume)). CT measurements and NT-pro-BNP/troponin I serum levels were correlated with RVD at echocardiography. 77 patients with RVD showed significantly higher RV/LV ratios and NT-pro-BNP/troponin I levels compared to those without RVD (RV/LV(axial) 1.68+/-0.84 versus 1.00+/-0.21; RV/LV(4-CH) 1.52+/-0.45 versus 1.01+/-0.21; RV/LV(volume) 1.97+/-0.53 versus 1.07+/-0.52; serum NT-pro-BNP 6,372+/-2,319 versus 1,032+/-1,559 ng.L(-1); troponin I 0.18+/-0.41 versus 0.06+/-0.18 g.L(-1)). The area under the curve for the detection of RVD of RV/LV(axial), RV/LV(4-CH), RV/LV(volume), NT-pro-BNP and troponin I were 0.84, 0.87, 0.93, 0.83 and 0.70 respectively. The combination of biomarkers and RV/LV(volume) increased the AUC to 0.95 (RV/LV(volume) with NT-pro-BNP) and 0.93 (RV/LV(volume) with troponin I). RV/LV(volume) is the most accurate CT parameter for identifying patients with RVD. A combination of RV/LV(volume) with NT-pro-BNP or troponin I measurements improves the diagnostic accuracy of either test alone.

• Image findings of patients with H1N1 virus pneumonia and acute respiratory failure

  Authors: T. Henzler, M. Meyer, A. Kalenka, M. Alb, G. Schmid-Bindert, S. Bartling, J. U. Schoepf, S. O. Schoenberg, C. Fink

  Acad Radiol. 17(6):681-5.

  RATIONALE AND OBJECTIVES: The aim of this study was to assess the findings of chest radiography and high-resolution computed tomography in patients requiring intensive care unit treatment for severeRATIONALE AND OBJECTIVES: The aim of this study was to assess the findings of chest radiography and high-resolution computed tomography in patients requiring intensive care unit treatment for severe H1N1 virus pneumonia. MATERIALS AND METHODS: In 2009, 10 patients required treatment in an intensive care unit for confirmed H1N1 pneumonia. All patients underwent chest radiography and high-resolution computed tomography. All 10 patients required mechanical ventilation because of respiratory failure. Nine patients presented with severe acute respiratory distress syndrome, and one patient died. Four patients underwent extracorporeal membrane oxygenation (ECMO) therapy. The results of chest radiography and high-resolution computed tomographic scans of these patients were systematically analyzed. RESULTS: The mean age of all patients was 44.1 +/- 12.3 years. All 10 patients showed abnormal results on chest radiography. The radiographic abnormalities were bilateral and multifocal in 10 patients. The predominant radiographic findings were consolidations (n = 9), ground-glass opacities (n = 8), and reticular opacities (n = 2). The most frequent computed tomographic findings at presentation consisted of bilateral ground-glass opacities (n = 9), pleural effusion (n = 9), areas of consolidation (n = 8), interstitial marking (n = 8), and crazy paving (n = 4). All patients undergoing ECMO therapy showed extensive bilateral ground-glass opacities, multifocal areas of consolidation, and crazy paving. Pleural effusion was present in three of four patients undergoing ECMO therapy. CONCLUSION: Patients requiring treatment in an intensive care unit for severe H1N1 pneumonia are at high risk for developing acute respiratory distress syndrome and frequently require ECMO therapy.