Signa excite hdxt

MRI was performed at both the University of Fukui and Osaka University. At the University of Fukui, a 3-T MR scanner (Discovery MR 750; General Electric Medical Systems) was used for high-resolution T1-weighted anatomical MRI (repetition time = 6.38 ms, echo time = 1.99 ms, flip angle = 11°, field of view = 256 × 256 mm², 256 × 256 matrix size, 172 slices, voxel dimensions = 1.0 × 1.0 × 1.0 mm³). At Osaka University, two kinds of 3-T MR scanners (Discovery MR 750w and Signa Excite HDxt; General Electric Medical Systems) were used for high-resolution T1-weighted anatomical MRI (repetition time = 880 ms, echo time = 0.016 ms, flip angle = 5°, field of view = 256 × 256 mm², 256 × 256 matrix size, 480 slices, voxel dimensions = 0.94 × 0.94 × 0.94 mm³; and repetition time = 10.084 ms, echo time = 3.04 ms, flip angle = 18°, field of view = 512 × 512 mm², 512 × 512 matrix size, 248 slices, voxel dimensions = 0.43 × 0.43 × 0.43 mm³).

Seven out of 22 subjects, who executed the two experimental sessions of the Experiment 2, during the INSIDE session were also examined by means of an fMRI test. MRI examination was performed on a 1.5 T MR system (Signa Excite HDxt, General Electric Healthcare, Waukesha, WI, USA) and included the following series covering the whole brain: axial FLAIR sequence (slice thickness = 5 mm; TR = 9002 ms; TE = 97.5 ms; inversion time = 2250 ms; flip angle = 90°; FOV = 240 mm × 240 mm; matrix = 512 × 512) to exclude incidental findings in the enrolled subjects; axial T2-weighted sequence (slice thickness = 5 mm; TR = 6300 ms; TE = 123.7 ms; FOV = 260 mm × 260 mm; matrix = 256 × 256) used as structural reference for the fMRI acquisition; T2^∗-weighted single-shot EPI sequences (32 slices; slice thickness = 4 mm; gap = 0.5 mm; TR = 3000 ms; TE = 40 ms; FOV = 260 mm × 260 mm; matrix = 64 × 64) for fMRI. Particularly, each fMRI run included 63 brain volumes; the first 3 volumes were discarded because of non-steady magnetization. Within each run the subject performed the handwriting motor task (i.e., active task) alternatively with a rest condition (i.e., control), according to a block designed paradigm consisting of 30-sec active task periods alternating with 30-s control periods (10 brain volumes per block).

The pre-clinical MR imaging protocol was developed for an experimental mouse-dedicated volume coil with a diameter of 55 mm (linear birdcage transmit/receive coil, Flick Engineering Solutions BV-General Electric-Baio G.) applied to a clinical 3T MR system (Signa EXCITE®HDxT, GE, Milwaukee, USA). The MR protocol applied to these new cancer animal model experiments was as previously described [15 (link)].
As previously established [15 (link)], the manganese chloride solution (Sigma Chemical Co., St. Louis, MO, USA) was prepared (5 mM MnCl₂ solution in 0.9% NaCl) and 180 μl per mouse were manually injected in the tail vein (corresponding to a dose range between 7.4 mg/kg in a 24 g mouse and 8.5 mg/kg in a 21 g mouse; animal weights were within the mentioned range). MR imaging was performed before and immediately after manganese administration was completed at the following time points 10, 30, 60 and 90 minutes, for the orthotopic cancer animal models (breast or prostate) and at 10, 30, 60, 90 minutes until 3 hours, for the metastatic cancer animal models (breast or prostate), in order to study the dynamics of manganese uptake per each metastatic lesion.