Prohance

Muscles in the upper arms and/or thighs were evaluated by MRI using a 1.5T unit (MAGNETOM Symphony or Avanto; Siemens Healthineer, Erlangen, Germany) or 3.0T unit (MAGNETOM Skyra or Vida; Siemens Healthineer, Erlangen, Germany) following a standardised protocol.12 (link) The left and right thighs were imaged simultaneously, whereas the left and right upper arms were imaged separately. Short-tau inversion recovery (STIR) imaging and fat-saturated (FS) Gd-T1-weighted imaging (T1WI) were performed in the axial and coronal planes. The contrast agents used in this study, namely, gadopentetate dimeglumine (Magnevist; Bayer Yakuhin, Osaka, Japan), gadodiamide (Omniscan; Daiichi Sankyo, Tokyo, Japan) and gadoteridol (ProHance; Eisai, Tokyo, Japan) were administered at a dose of 0.2 mmol/kg body weight.

All imaging was performed on a 3T MR scanner (MAGNETOM Skyra, Siemens Healthcare, Erlangen, Germany) with a 32 channel-phased array head coil. MR examinations were performed before and 4 hours after IV-SD-GBCA (0.1 mmol/kg body weight) to evaluate the degree of EH. For the GBCA, a macrocyclic agent, gadoteridol (Gd-HP-DO3A; ProHance, Eisai, Tokyo, Japan), was administered. The patients underwent an MRC and an hT₂W-3D-FLAIR sequence, according to a previously reported protocol used for the evaluation of EH.^{12 –15 (link)} For the MRC, a heavily T₂W 3D-turbo spin echo sequence (TR = 4400 ms, TE = 544 ms) with a variable refocusing flip angle was used. The hT₂W-3D-FLAIR was a similar sequence type to the MRC; however, a non-selective inversion recovery pulse and extended TR were applied in this sequence (TR = 9000 ms, TE = 544 ms, TI = 2250 ms). The resolution parameters and the range of imaging axial slabs were aligned in both sequences. The voxel size was 0.5 × 0.5 × 1.0 mm³. The slab thickness was 104 mm. The oblique degree of imaging slab was parallel to the anterior commissure (AC)–posterior commissure (PC) line and bilateral internal auditory canal in the axial section, and the center was set at the level of internal auditory canal. The details of the imaging parameters are indicated in Table 1.

Magnetic resonance data were acquired by either a 1.5-T or a 3-T MR imaging unit, manufactured by GE Medical Systems (Milwaukee, Wis), Siemens Healthcare (Erlangen, Germany), Philips Medical Systems (Best, the Netherlands), Hitachi Medical Corporation (Tokyo, Japan), or Toshiba Medical Systems (Otawara, Japan) at 22 participating sites. Conventional MRI data were obtained with the T1WI sequences, 2-dimensional T1-weighted spin-echo sequence or 3-dimensional T1-weighted gradient-echo sequence, the T2-weighted spin-echo imaging (T2WI) sequence, and the fluid-attenuated inversion-recovery (FLAIR) sequence. In addition, acquired CE-T1WIs shortly after intravenous injection of a standard dose (0.1 mmol/kg body weight) of a gadolinium-based contrast agent, including gadobutrol (Gadovist; Bayer Yakuhin), gadopentetate dimeglumine (Magnevist; Bayer Yakuhin), gadoteridol (ProHance; Eisai, Tokyo, Japan), gadodiamide (Omniscan; GE Healthcare Pharma, Tokyo, Japan), or gadoterate meglumine (Magnescope; Guerbet Japan, Tokyo, Japan), were matched to precontrast T1WIs obtained with similar sequence parameters.
Diffusion-weighted imaging was performed using a single-shot spin-echo echo-planar sequence. Diffusion-sensitizing gradients were sequentially applied in the x, y, and z directions with b factors of 0 and 800 to 2000 s/mm².