Spatial-temporal perfusion patterns of the human liver assessed by pseudo-continuous arterial spin labeling MRI.

Purpose: To investigate the capabilities of a modern pseudo-continuous arterial spin labeling (PCASL) technique for non-invasive assessment of the temporal and spatial distribution of the liver perfusion in healthy volunteers on a clinical MR system at 3T.

Materials And Methods: A 2D-PCASL multi-slice echo planar imaging sequence was adapted to the specific conditions in liver: a) labeling by PCASL was optimized to the flow characteristics in the portal vein, b) background suppression was applied for reduction of motion related artifacts, c) post labeling delays (PLDs) were varied over a large range (0.7-3.

Fast non-enhanced abdominal examination protocols in PET/MRI for patients with neuroendocrine tumors (NET): comparison to multiphase contrast-enhanced PET/CT.

Purpose: To evaluate fast non-enhanced protocols for abdominal PET/MRI in comparison to contrast-enhanced PET/CT with somatostatin receptor (SSR)-specific radiotracers regarding effectiveness of lesion detection in NET patients.

Methods: This was a retrospective analysis of 29 patients (12 male, 57 ± 13 years) who underwent PET/CT and subsequently PET/MRI at the same day. Two readers evaluated independently four PET/MRI setups: (I) PET + T2 Half Fourier Acquisition Single Shot Turbo Spin Echo (T2 HASTE), (II) PET + T2 HASTE + T2-weighted spin-echo sequence (T2 TSE), III) PET + T2 HASTE + Diffusion Weighted Imaging (DWI) and (IV) PET + T2 HASTE + T2 TSE + DWI.

Simultaneous multislice diffusion-weighted imaging in whole-body positron emission tomography/magnetic resonance imaging for multiparametric examination in oncological patients.

Objectives: The aim of this study was to compare the diagnostic performance of simultaneous multislice diffusion-weighted imaging (DWI-SMS) with that of standard DWI (DWI-STD) in whole-body 3-T PET/MRI examination protocols in oncological patients.

Methods: In a phantom study, we evaluated the apparent diffusion coefficients (ADC) from the two techniques. In ten volunteers, we assessed ADC values in different organs.

Characterization of Severe Arterial Phase Respiratory Motion Artifact on Gadoxetate Disodium-Enhanced MRI - Assessment of Interrater Agreement and Reliability.

Purpose:  To assess the interrater agreement and reliability of experienced abdominal radiologists in the characterization and grading of arterial phase gadoxetate disodium-related respiratory motion artifact on liver MRI.

Materials And Methods:  This prospective multicenter study was initiated by the working group for abdominal imaging within the German Roentgen Society (DRG), and approved by the local IRB of each participating center. 11 board-certified radiologists independently reviewed 40 gadoxetate disodium-enhanced liver MRI datasets.

Scan time reduction in diffusion-weighted imaging of the pancreas using a simultaneous multislice technique with different acceleration factors: How fast can we go?

Objectives: To investigate the feasibility of simultaneous multislice-accelerated diffusion-weighted imaging (sms-DWI) of the pancreas with different acceleration factors and its influence on image quality, acquisition time and apparent diffusion coefficients (ADCs) in comparison to conventional sequences.

Methods: DWI of the pancreas was performed at 1.5T in ten healthy volunteers and 20 patients with sms-accelerated echo-planar DWI using two different sms-acceleration factors of 2 and 3 (sms2/3-DWI).