[Evaluation of a novel seldinger-needle for computed tomography guided interventions: initial experiences].

Purpose: To evaluate a new Seldinger puncture device for computed tomography-guided interventions under difficult conditions, to analyze applicability, and to investigate assets and drawbacks.

Materials And Methods: From November 2007 to March 2008, we performed CT-guided interventions in 16 patients (7 women, 9 men; mean age 62 years old) using a new 20G-Seldinger needle (Sika-Med, Wiehl, Germany). This novel needle serves as a guide for many different interventional devices due to a guide wire welded on the proximal needle end.

Contrast enhancement in chest multidetector computed tomography: intraindividual comparison of 300 mg/ml versus 400 mg/ml iodinated contrast medium.

Rationale And Objectives: We sought to intraindividually compare intravascular contrast enhancement in multidector computed tomography (MDCT) of the chest using contrast media (CM) containing 300 and 400 mg iodine/ml.

Materials And Methods: Seventy-one patients underwent repeated MDCT scanning of the chest at baseline and follow-up. CM with standard iodine (protocol A: 300 mg iodine/ml; Iopromide 300) and high iodine concentration (protocol B: 400 mg iodine/ml; Iomeprol 400) were used.

Automated measurement of lymph nodes: a phantom study.

The purpose of this study was to assess the accuracy of automated nodal quantification in a phantom. MDCT of a phantom with 17 synthetic lymph nodes of different sizes (diameter 6.0-30.

Semi-automated quantification of hepatic lesions in a phantom.

Purpose: Accurate measurement is crucial for the assessment of tumor dimensions to allow accurate evaluation of tumor response. Thus, the purpose of our study was to assess the accuracy of semi-automated RECIST and volumetric measurements of liver lesions in a liver phantom with different CT acquisition parameters.

Materials And Methods: A phantom of the upper abdomen with 14 hepatic lesions of different sizes (diameter: 12.

Image fusion in dual energy computed tomography: effect on contrast enhancement, signal-to-noise ratio and image quality in computed tomography angiography.

Objective: The aim of this study was to evaluate the influence of different weighting factors on contrast enhancement, signal-to-noise ratio (SNR), and image quality in image fusion in dual energy computed tomography (DECT) angiography.

Material And Methods: Fifteen patients underwent a CT angiography of the aorta with a SOMATOM Definition Dual Source CT (DSCT; Siemens, Forchheim, Germany) in dual energy mode (DECT) (tube voltage: 80 and 140 kVp; tube current: 297 eff. mA and 70 eff.

Correlation of C-reactive protein with survival and radiographic response to first-line platinum-based chemotherapy in advanced non-small cell lung cancer.

Objective: This study was conducted to assess the prognostic role of regular measurements of C-reactive protein (CRP) in patients with advanced-stage non-small cell lung cancer (NSCLC) during platinum-based first-line therapy.

Methods: A total of 210 patients were retrospectively analyzed regarding CRP values, infections, histological type, stage, performance status, gender, age, body mass index and survival. Additionally, in 88 of these patients, changes of CRP values were correlated with response to chemotherapy by radiographic imaging.

Electromagnetic tracking for CT-guided spine interventions: phantom, ex-vivo and in-vivo results.

An electromagnetic-based tracking and navigation system was evaluated for interventional radiology. The electromagnetic tracking system (CAPPA IRAD EMT, CASinnovations, Erlangen, Germany) was used for real-time monitoring of punctures of the lumbar facet joints and intervertebral disks in a spine phantom, three pig cadavers and three anaesthesized pigs. Therefore, pre-interventional computed tomography (CT) datasets were transferred to the navigation system and puncture trajectories were planned.

Performance evaluation of a computer-aided detection algorithm for solid pulmonary nodules in low-dose and standard-dose MDCT chest examinations and its influence on radiologists.

The aim of the study was to evaluate the performance of a computer-aided detection (CAD) algorithm in low-dose and full-dose multidetector-row CT (MDCT) of the thorax and its impact on radiologists' performance. Chest CT examinations of 77 patients were evaluated retrospectively for pulmonary nodules. All patients had undergone a 16-slice MDCT chest examination with a standard acquisition protocol.

Bipolar radiofrequency ablation: is the shape of the coagulation volume different in comparison to monopolar RF-ablation using variable active tip lengths?

We investigated the differences between bipolar and monopolar radiofrequency (RF)-ablation devices regarding the shape and volume of the induced coagulation zone. RF-ablations were performed in freshly excised porcine liver. For bipolar RF-ablation needle electrodes with 9, 20 and 30 mm active tip lengths were used.

Introduction of a dedicated circulation phantom for comprehensive in vitro analysis of intravascular contrast material application.

Objectives: To develop a circulation phantom with physiologic circulation parameters, including a pulmonary and a body circulation for the evaluation of intravascular contrast material (CM) application.

Materials And Methods: The circulation phantom consists of a low-pressure venous system into which CM is injected, a pulmonary circulation, and high-pressure body circulation with an anthropometric aorta and coronary arteries. The phantom is driven by a pulsatile Harvard heart pump.

Multidetector computed tomography (MDCT) evaluation of myocardial viability: intraindividual comparison of monomeric vs. dimeric contrast media in a rabbit model.

To evaluate the influence of different types of iodinated contrast media on the assessment of myocardial viability, acute myocardial infarction (MI) was surgically induced in six rabbits. Over a period of 45 min, contrast-enhanced cardiac MDCT (64 x 0.6 mm, 80 kV, 680 mAs(eff.

Which Iodine concentration in chest CT?--a prospective study in 300 patients.

In computed tomography (CT) several contrast media with different iodine concentrations are available. The aim of this study is to prospectively compare contrast media with iodine concentrations of 300, 370 and 400 mg iodine/ml for chest- CT. 300 consecutive patients were prospectively enrolled, under a waiver of the local ethics committee.

Functional imaging in the assessment of myocardial infarction: MR imaging vs. MDCT vs. SPECT.

Purpose: To intraindividually compare magnetic resonance (MR) imaging, ECG-gated multi-detector spiral computed tomography (MDCT) and gated single photon emission computed tomography (SPECT) for the evaluation of global and regional myocardial function and the identification of myocardial perfusion abnormalities.

Materials And Methods: Nine patients (8 men; 55.1+/-8.

Imaging of the coronary venous system in patients with congestive heart failure: comparison of 16 slice MSCT and retrograde coronary sinus venography: comparative imaging of coronary venous system.

Background: Knowledge of the anatomy of the coronary venous system (CVS) is important for planning of cardiac interventions like cardiac resynchronization therapy or percutaneus mitral annuloplasty. Different methods have been used for preprocedural visualization of the CVS. However, limited data is available comparing invasive retrograde coronary sinus angiography (CSA) and non-invasive multi slice computed tomography (MSCT).

Magnetic thermal ablation using ferrofluids: influence of administration mode on biological effect in different porcine tissues.

The purpose of this study was to compare the effects of magnetic thermal ablation in different porcine tissues using either a singular injection or a continuous infusion of superparamagnetic iron oxide nanoparticles. In the first setting samples of three ferrofluids containing different amounts of iron (1:171, 2:192, and 3:214 mg/ml) were singularly interstitially injected into specimens of porcine liver, kidney, and muscle (n = 5). Then the specimens were exposed to an alternating magnetic field (2.

Carbon dioxide contrast agent for CT arteriography: results in a porcine model.

Purpose: To test the feasibility of carbon dioxide (CO(2))-enhanced computed tomographic (CT)-arteriography in an animal model.

Materials And Methods: Five domestic swine underwent digital subtraction angiography (DSA), conventional CT angiography with iodinated contrast material, and CO(2)-enhanced CT arteriography. For each CO(2)-enhanced DSA image series, 100 mL of pressurized CO(2) was injected at 1.

Intraindividual comparison of contrast media concentrations for combined abdominal and thoracic MDCT.

Objective: The purpose of this study was an intraindividual comparison of the degrees of MDCT contrast enhancement achieved with agents containing 300 and 370 mg I/mL.

Subjects And Methods: Seventy-five patients underwent baseline and follow-up MDCT of the chest and abdomen with contrast media containing a high concentration of iodine (iopromide 370 mg I/mL) and standard iodine concentration (iopromide 300 mg I/mL). The total iodine load (37 g) and the iodine delivery rate (1.

Semi-automated measurement of hyperdense, hypodense and heterogeneous hepatic metastasis on standard MDCT slices. Comparison of semi-automated and manual measurement of RECIST and WHO criteria.

As semi-automated measurement would be desirable for lesion quantification and therapy-response control, the purpose of this study was to compare semi-automated measurements with manual assessment of different types of hepatic metastases. Seventy-six patients with known liver metastases were analysed. All of them underwent contrast-enhanced 16-MDCT (16 x 0.

Impact of different vein catheter sizes for mechanical power injection in CT: in vitro evaluation with use of a circulation phantom.

The purpose of this study was to evaluate the influence of different peripheral vein catheter sizes on the injection pressure, flow rate, injection duration, and intravascular contrast enhancement. A flow phantom with a low-pressure venous compartment and a high-pressure arterial compartment simulating physiological circulation parameters was used. High-iodine-concentration contrast medium (370 mg iodine/ml; Ultravist 370) was administered in the venous compartment through peripheral vein catheters of different sizes (14, 16, 18, 20, 22, and 24 G) using a double-head power injector with a pressure limit of 325 psi.

[Computer-aided detection of small pulmonary nodules in multidetector spiral computed tomography (MSCT) in children].

Purpose: Retrospective evaluation of computer-aided detection software (CAD) for automated detection (LungCAD, Siemens Medical solutions, Forchheim, Germany) and volumetry (LungCARE) of pulmonary nodules in dose-reduced pediatric MDCT.

Materials And Methods: 30 scans of 24 children (10.4+/-5.

Perfusion weighted color maps for enhanced visualization of myocardial infarction by MSCT: preliminary experience.

Purpose: The reliable detection of myocardial perfusion defects and myocardial infarction (MI) is of great interest in the comprehensive workup of coronary artery disease. The aim of this study was to optimize the ability of contrast-enhanced cardiac multislice spiral computed tomography (MSCT) for detecting hypoperfused myocardium as surrogate marker of MI using a newly developed post-processing technique.

Methods: First a model-based software tool for semi-automated detection of the long axis of the left ventricle and assignment of left-ventricular segments was developed using a region growing algorithm and a point distribution model.

Imaging of the coronary venous system: validation of three-dimensional rotational venous angiography against dual-source computed tomography.

Information on the anatomy of the cardiac venous system (CVS) is increasingly important for cardiac resynchronization therapy or percutaneous transvenous mitral valve annuloplasty. Three-dimensional (3D) imaging can further improve the understanding of the relationship of cardiac structures. This study was performed to validate the accuracy of rotational coronary sinus angiography (CSA) displaying the 3D anatomy of the CVS compared to ECG-gated, contrast-enhanced, cardiac dual-source computed tomography (DSCT).

Assessment of global right ventricular function on 64-MDCT compared with MRI.

Objective: The aim of this study was to compare ECG-gated 64-MDCT with MRI for the assessment of global right ventricular (RV) function from coronary CT angiography data.

Subjects And Methods: Thirty-eight patients (25 men, 13 women; mean age +/- SD, 55.0 +/- 8.

Pediatric multidetector computed tomography using tube current modulation and a patient image gallery.

Background: Dose reduction is crucial in pediatric multidetector computed tomography (MDCT).

Purpose: To perform pediatric 16-slice MDCT using tube current modulations and to adjust prospectively the tube current using a patient image gallery (IG) providing simulated dose-reduced protocols; and to evaluate and compare the image quality of the IG and the clinical MDCT.

Material And Methods: 30 examinations (thorax, n = 15; abdomen, n = 8; pelvis, n = 7) in 20 patients (nine male, age 8.

MDCT angiography of the pulmonary arteries: intravascular contrast enhancement does not depend on iodine concentration when injecting equal amounts of iodine at standardized iodine delivery rates.

To compare the impact of iodine concentration using two different contrast materials (CM) at standardized iodine delivery rate (IDR) and overall iodine load in 16-multidetector-row-CT-angiography (MDCTA) of the pulmonary arteries of 192 patients with known or suspected pulmonary embolism. One hundred three patients (group A) received 148 ml of a CM containing 300 mg iodine/ml (Ultravist 300, BayerScheringPharma) at a flow rate of 4.9 ml/s.