Reducing the radiation dose for low-dose CT of the paranasal sinuses using iterative reconstruction: feasibility and image quality.

Purpose: To evaluate image quality of dose-reduced CT of the paranasal-sinus using an iterative reconstruction technique.

Methods: In this study 80 patients (mean age: 46.9±18 years) underwent CT of the paranasalsinus (Siemens Definition, Forchheim, Germany), with either standard settings (A: 120 kV, 60 mAs) reconstructed with conventional filtered back projection (FBP) or with tube current-time product lowering of 20%, 40% and 60% (B: 48 mAs, C: 36 mAs and D: 24 mAs) using iterative reconstruction (n=20 each).

Bilateral contrast-enhanced MR angiography of the hand: diagnostic image quality of accelerated MRI using echo sharing with interleaved stochastic trajectories (TWIST).

Objectives: To evaluate the image quality of time-resolved contrast-enhanced MRA (tr-MRA) employing echo-sharing with stochastic trajectories for the bilateral examination of the hands.

Methods: In this institutional review-board approved study, Tr-MRA was compared with multiphasic contrast-enhanced MRA (mp-MRA) featuring sub-systolic venous compression in 20 healthy volunteers at 3.0 T using the following settings: TR/TE: 2.

Thoracic aorta: prospective electrocardiographically triggered CT angiography with dual-source CT--feasibility, image quality, and dose reduction.

Purpose: To prospectively investigate the feasibility, image quality, and radiation dose for prospective electrocardiographically (ECG) triggered sequential dual-source computed tomographic (CT) angiography of the thoracic aorta in comparison to retrospective ECG-gated helical dual-source CT angiography.

Materials And Methods: This study was approved by the institutional review board; informed consent was obtained. One hundred thirty-nine patients referred for ECG-assisted dual-source CT angiography of the thoracic aorta were prospectively enrolled.

Image analysis in time-resolved large field of view 3D MR-angiography at 3T.

Purpose: To qualitatively and quantitatively evaluate the image quality in accelerated time-resolved 3D contrast-enhanced MR angiography (tr-CE-MRA) at 3T.

Materials And Methods: In all, 113 MRA were performed in 107 patients on a 3T MR system after written informed consent and approval by the ethics committee. Twenty consecutive thoracic (n=87) or craniocervical (n=26) 3D data volumes were acquired.

Bilateral ce-MR angiography of the hands at 3.0 T and 1.5 T: intraindividual comparison of quantitative and qualitative image parameters in healthy volunteers.

The purpose of this study was to determine the benefit of bilateral contrast-enhanced MR angiography (ce-MRA) of the hands at 3.0 Tesla (T) compared with an established 1.5-T technique in healthy volunteers.

Visualization of iliac and proximal femoral artery hemodynamics using time-resolved 3D phase contrast MRI at 3T.

Purpose: To demonstrate the feasibility of time-resolved 3D MR velocity mapping at 3 Tesla for the visualization of vascular hemodynamics in normal iliac and femoral arteries.

Materials And Methods: Electrocardiographically (ECG) synchronized three-dimensional (3D) CINE phase-contrast MRI with three-directional flow encoding was adapted to analyze flow in peripheral arteries at 3T. Visualization of peripheral arterial hemodynamics within the acquired data volume included 3D streamlines and time-resolved 3D particle traces within the major vessels and localized analysis of flow profiles using 2D-vector graphs.

Accelerated time-resolved 3D contrast-enhanced MR angiography at 3T: clinical experience in 31 patients.

Purpose: To evaluate whether time-resolved 3D MR-angiography at 3T with a net acceleration factor of eight is applicable in clinical routine and to evaluate whether good image quality and a low artifact level can be achieved with a temporal update rate that allows for additional information on pathologies.

Materials And Methods: Thirty-one consecutive patients underwent time-resolved 3D contrast-enhanced MR-angiography on a 3T system. Imaging consisted of accelerated 3D gradient echo sequences combining parallel imaging with an acceleration factor of four, partial Fourier acquisition along phase and slice encoding direction, and twofold temporal acceleration using view sharing.

Comparison of the detectability of high- and low-contrast details on a TFT screen and a CRT screen designed for radiologic diagnosis.

Rationale And Objectives: To evaluate the detection rate of fine details of a new thin-film transistor (TFT) grayscale monitor designed for radiologic diagnosis, compared with a type of cathode ray tube (CRT) screen used routinely for diagnostic radiology.

Methods: Fifteen radiographs of a statistical phantom presenting low- and high-contrast details were obtained and read out with an Agfa ADC compact storage phosphor system. Each radiograph presented 60 high-density (high-contrast) and 60 low-density (low-contrast) test bodies.

Pancreatico-mediastinal fistula with a mediastinal mass lesion demonstrated by MR imaging.

Internal pancreatic fistulas are uncommon but well-recognized complications of inflammatory pancreatic disease. A case of a pancreatico-mediastinal fistula with a mediastinal mass lesion in a patient with a documented history of chronic alcohol consumption and previous episodes of acute pancreatitis is described. Since the clinical symptomatology was dominated by pulmonary complaints, magnetic resonance (MR) imaging using a breathhold coronal T2-weighted sequence with spectral fat saturation was essential in clarifying this difficult and rare pathology.

Pulmonary sequestration: demonstration of blood supply with 2D and 3D MR angiography.

Pulmonary sequestration is a relatively rare but clinically significant congenital anomaly. This disease is a spectrum of disorders involving the pulmonary airways, the arterial supply to the lungs, the lung parenchyma and its venous drainage. Traditionally, the diagnosis of pulmonary sequestration has been made definitively with arterial angiography.

Contrast enhanced MR angiography in the assessment of relevant stenoses in occlusive disease of the pelvic and lower limb arteries: diagnostic value of a two-step examination protocol in comparison to conventional DSA.

Introduction/objectives: Contrast-enhanced MRA (ce-MRA) has been claimed by many authors as a replacement of conventional angiography evaluating peripheral arterial occlusive disease. However, reliable detection of relevant stenoses (>70%) has to be provided for planning vascular interventions. Only few data in the literature focuses on this crucial problem.