Lumirem

MR Imaging was performed with a 1.5T scanner (Magnetom Symphony, Siemens Medical System, Erlangen, Germany) equipped with a phased-array body coil. Patients were placed in a supine, headfirst position. Mild rectal lumen distension was achieved with 60-90 ml of ultrasound gel or superparamagnetic contrast medium (Lumirem; Guerbet, Roissy CdG Cedex, France) introduced per rectum. Pre-contrast sagittal and axial T2 weight (W) 2D turbo spin-echo (TSE) images of the pelvis were obtained. Axial, dynamic, contrast enhanced T1W, FLASH 3D gradient-echo (GRE) images were acquired for the qualitative (q) MRI analysis (inspective analysis of TIC). We obtained one sequence before and ten sequences, without any delay, after IV injection of 2 ml/kg of a positive, gadolinium based paramagnetic contrast medium (Gd- DOTA, Dotarem, Guerbet, Roissy CdG Cedex, France). The contrast medium was injected using Spectris Solaris® EP MR (MEDRAD Inc., Indianola, PA), with a flow rate of 2 ml/s, followed by a 10-mL saline flush at the same rate. Total acquisition time for pre-contrast and ten post-contrast sequences was 6.4 minutes. Sagittal, axial and coronal post contrast T1W 2D TSE, with and without fat saturation were obtained. The details of pulse Sequence Parameters are reported in Table 5.

MR examinations were performed on a 1.5 T system (Magnetom Avanto, Siemens, Erlangen, Germany) using dedicated multichannel surface coils covering the abdomen. Prior to image acquisition, patients received 200 mL of a negative oral contrast agent (Lumirem®; Guerbet, Sulzbach, Germany) for suppression of gastroenteric fluid signal, as well as 20 mg butylscopolamine (Buscopan®; Boehringer Ingelheim, Ingelheim, Germany; administered as a bolus over approximately 20 s) i.v. for spasmolysis. All patients underwent a clinical routine imaging protocol of the liver, including a respiratory-triggered 3D MR cholangiography in the coronal (dataset A) as well as in the axial (dataset B) plane. MRCP-sequences were acquired prior to intravenous contrast injection. The specific MRCP sequences had sequential k-space filling with partial Fourier filling allowed, resulting in acquisition of central k-space lines approximately 3 minutes after the start of the sequence. MRCP sequence parameters are provided in detail in Table 1.