[Unusual intensive care course in a patient with head injuries]. / Ungewöhnlicher intensivmedizinischer Verlauf bei einem Patienten nach Schädel-Hirn-Trauma.

This article reports the case of a patient who developed a sudden impairment of gas exchange, renal function and a distended abdomen 13 days after admission to the intensive care unit. The combination of a sudden platelet drop, the timing of heparin administration and evidence of thromboembolic events by computed tomography (CT) led to the suspected diagnosis of heparin-induced thrombocytopenia (HIT) type II which was confirmed by laboratory testing. HIT is a life-threatening complication of heparin anticoagulation and CT is an important diagnostic instrument for detecting the location and extent of thromboembolic manifestations, thereby enabling the initiation of therapy to prevent further complications.

[An unusual breast tumor]. / Ein ungewöhnlicher Mammatumor.

The presented case shows how difficult it can be to diagnose rare diseases if they present with masses in atypical locations. In an extensive further diagnostic workup other characteristic findings then point to the correct diagnosis.

Predictive value of PET-CT imaging versus AGO-scoring in patients planned for cytoreductive surgery in recurrent ovarian cancer.

OBJECTIVE: To assess the predictive value of positron emission tomography computed tomography (PET-CT) imaging in comparison to AGO-scoring in patients planned for cytoreductive surgery in recurrent ovarian cancer. MATERIALS AND METHODS: 33 patients who had received a PET-CT for suspicion of recurrent ovarian cancer between 12/2003 and 08/2007 were included in the retrospective analysis. Indication for PET-CT was based on blood tumor markers Ca 125 or Ca 72-4 and clinical symptoms. Scanning was performed on a Philips Gemini System covering the body from the neck to the thighs one hour after administration of 200MBq fluorodesoxyglucose. PET-CT, surgery and the patient records were reviewed to analyze the predictive value of PET-CT in comparison to an AGO-scoring system based on clinical parameters with regard to the prediction of full resectability of abdominal tumor spread. RESULTS: The statistical analysis of this data showed a sensitivity of 73% (95% C.I., 39-94%) and specificity of 80% (95% C.I., 29-97%) for AGO-scoring with a positive predictive value of 89% and a negative predictive value of 57%. PET-CT achieved a sensitivity of 100% (95% C.I., 72-100%) and specificity of 60% (95% C.I. 15-94%), with a positive predictive value of 85% and negative predictive value of 100%. Further analysis of the data of operated patients with concordant PET-CT and AGO-score (12/16) showed a very good prediction of full resectability with a sensitivity of 100% (95% C.I., 63-100%), specificity of 75% (95% C.I., 20-96%), positive predictive value of 89% and negative predictive value of 100%. CONCLUSION: PET-CT and the AGO-score offer good tools to determine patients for full resectability in recurrent ovarian cancer. PET-CT has a higher negative and the AGO score a higher positive predictive value, and the combination of both improves the diagnostic accuracy.

Automated quantification of pulmonary perfused blood volume by dual-energy CTPA in chronic thromboembolic pulmonary hypertension.

OBJECTIVES: The aim of the study was to determine whether automated quantification of pulmonary perfused blood volume (PBV) in dual-energy computed tomography pulmonary angiography (DE-CTPA) can be used to assess the severity of chronic thromboembolic pulmonary hypertension (CTEPH). METHODS: Automated quantification of PBV was performed in 25 consecutive CTEPH patients undergoing DE-CTPA. PBV values were correlated with cardiac index and pulmonary vascular resistance quantified by right heart catheterization and walking distance in the 6-minute walk test using Pearson's correlation coefficient and multivariate linear regression analysis to control for age and gender. RESULTS: DE-CTPA derived PBV values inversely correlated with systolic (r = -0.64, p = 0.001) and mean (r = -0.57, p = 0.004) pulmonary arterial pressure. There was a trend for PBV values to inversely correlate with pulmonary vascular resistance (r = -0.20, p = 0.35). No significant correlation was found between PBV values and cardiac index or 6-minute walking distance. These correlations were confirmed to be independent of age and gender on multivariate linear regression analysis. CONCLUSION: DE-CTPA can be used for an automated quantification of pulmonary PBV in chronic thromboembolic pulmonary hypertension. PBV values correlate inversely with systolic and mean pulmonary arterial pressure and can thus be used to estimate the severity of pulmonary hypertension in these patients. Citation Format: • Meinel FG, Graef A, Thierfelder KM et al. Automated Quantification of Pulmonary Perfused Blood Volume by Dual-Energy CTPA in Chronic Thromboembolic Pulmonary Hypertension. Fortschr Röntgenstr 2014; 186: 151 - 156.

Dual-energy CT pulmonary angiography in patients with suspected pulmonary embolism: value for the detection and quantification of pulmonary venous congestion.

OBJECTIVE: To evaluate if vascular and pulmonary parenchymal enhancement values in dual-energy (DE) CT pulmonary angiography (CTPA) can suggest the diagnosis of pulmonary congestion. METHODS: DE-CTPA images of 90 out of 1321 patients negative for pulmonary embolism showed signs of congestive heart failure. We measured DE-derived pulmonary parenchymal [perfused blood volume (PBV)], pulmonary artery (PA) and left atrium (LA) enhancement values in these patients and in 142 control patients. Enhancement values were compared between the populations and correlated with serum values of B-type natriuretic peptide (BNP) and proBNP, where available. RESULTS: No significant difference of PBV but significant differences of mean PA and LA enhancement and individual enhancement differences (PA - LA) were found between the populations. PA - LA was higher in patients with elevated BNP and proBNP and was positively correlated with these values. Receiver operating characteristic analysis revealed a moderate discriminatory power of the PA - LA difference for the presence of cardiac biomarker elevations. CONCLUSION: PBV in DE-CTPA is not altered in patients with signs of congestive heart failure. However, differences in enhancement values in the pre- and post-pulmonary vessels were found in comparison with the control population. ADVANCES IN KNOWLEDGE: Altered pulmonary vascular haemodynamics in pulmonary venous congestion are not reflected in dual-energy-derived PBV maps. In the diagnosis of left heart failure in patients with chest pain and dyspnoea, density measurements in the pulmonary artery and in the left atrium in CTPA images may be a helpful diagnostic tool.

[Imaging for diagnostics of urolithiasis including dual-energy CT]. / Bildgebung zur Diagnostik der Urolithiasis einschließlich Dual-Energy-CT.

Patients with stone disease usually present to the urologist with acute colic pain. For the right choice of therapy the diagnosis needs to be confirmed using one of many imaging methods, including ultrasonography, abdominal radiography, intravenous urography, non-contrast-enhanced computed tomography (CT), CT and magnetic resonance imaging (MRI) urography and dual-energy CT. The techniques differ in the availability, diagnostic sensitivity and specificity and level of radiation exposure. Compared to the others dual-energy CT allows distinction between different stone compositions with high accuracy and can affect the choice of therapy. This article on imaging and diagnosis of urolithiasis discusses the different imaging methods and highlights dual-energy CT and its distinctive features.

Dual Energy CT lung perfusion imaging--correlation with SPECT/CT.

OBJECTIVE: Aims were (1) to determine the diagnostic accuracy of Dual Energy CT (DECT) in the detection of perfusion defects and (2) to evaluate the potential of DECT to improve the sensitivity for PE. METHODS: 15 patients underwent Dual Energy pulmonary CT angiography (DE CTPA) and a combination of lung perfusion SPECT/CT and ventilation scintigraphy. CTPA and DE iodine distribution maps as well as perfusion SPECT/CT and inhalation scintigrams were reviewed for pulmonary embolism (PE) diagnosis. DECT and SPECT perfusion images were assessed regarding localization and extent of perfusion defects. Diagnostic accuracy of DE iodine (perfusion) maps was determined with reference to SPECT/CT. Diagnostic accuracies for PE detection of DECT and of SPECT/CT with ventilation scintigraphy were calculated with reference to the consensus reading of all modalities. RESULTS: DE CTPA had a sensitivity/specificity of 100%/100% for acute PE, while the combination of SPECT/CT and ventilation scintigraphy had a sensitivity/specificity of 85.7%/87.5%. For perfusion defects, DECT iodine maps had a sensitivity/specificity of 76.7% and 98.2%. CONCLUSION: DECT is able to identify pulmonary perfusion defects with good accuracy. This technique may potentially enhance the diagnostic accuracy in the assessment of PE.

Quantitative assessment of left ventricular function with dual-source CT in comparison to cardiac magnetic resonance imaging: initial findings.

Cardiac magnetic resonance imaging and echocardiography are currently regarded as standard modalities for the quantification of left ventricular volumes and ejection fraction. With the recent introduction of dual-source computedtomography (DSCT), the increased temporal resolution of 83 ms should also improve the assessment of cardiac function in CT. The aim of this study was to evaluate the accuracy of DSCT in the assessment of left ventricular functional parameters with cardiac magnetic resonance imaging (MRI) as standard of reference. Fifteen patients (two female, 13 male; mean age 50.8 +/- 19.2 years) underwent CT and MRI examinations on a DSCT (Somatom Definition; Siemens Medical Solutions, Forchheim, Germany) and a 3.0-Tesla MR scanner (Magnetom Trio; Siemens Medical Solutions), respectively. Multiphase axial CT images were analysed with a semiautomatic region growing algorithms (Syngo Circulation; Siemens Medical Solutions) by two independent blinded observers. In MRI, dynamic cine loops of short axis slices were evaluated with semiautomatic contour detection software (ARGUS; Siemens Medical Solutions) independently by two readers. End-systolic volume (ESV), end-diastolic volume (EDV), ejection fraction (EF) and stroke volume (SV) were determined for both modalities, and correlation coefficient, systematic error, limits of agreement and inter-observer variability were assessed. In DSCT, EDV and ESV were 135.8 +/- 41.9 ml and 54.9 +/- 29.6 ml, respectively, compared with 132.1 +/- 40.8 ml EDV and 57.6 +/- 27.3 ml ESV in MRI. Thus, EDV was overestimated by 3.7 ml (limits of agreement -46.1/+53.6), while ESV was underestimated by 2.6 ml (-36.6/+31.4). Mean EF was 61.6 +/- 12.4% in DSCT and 57.9 +/- 9.0% in MRI, resulting in an overestimation of EF by 3.8% with limits of agreement at -14.7 and +22.2%. Rank correlation rho values were 0.81 for EDV (P = 0.0024), 0.79 for ESV (P = 0.0031) and 0.64 for EF (P = 0.0168). The kappa value of inter-observer variability were amounted to 0.85 for EDV, ESV and EF. DSCT offers the possibility to quantify left ventricular function from coronary CT angiography datasets with sufficient diagnostic accuracy, adding to the value of the modality in a comprehensive cardiac assessment. The observed differences in the measured values may be due to different post-processing methods and physiological reactions to contrast material injection without beta-blocker medication.