Avanto 1.5 tesla mri scanner

Retrospective clinical data from seven patients with rTOF were used to study the blood flow in models of the pulmonary bifurcation. Demographic information about each patient is reported in Table 1, with an average age of the population being 26.3 ± 15.7 and the grade of regurgitation fraction varying from moderate to severe. Images of the pulmonary trunk of these patients, used for model reconstruction (Figures 1A,B), were acquired between 2012 and 2017 with a Siemens Avanto 1.5-Tesla MRI scanner (Siemens Healthcare, Erlangen, Germany), using the protocol “3D and Phase contrast” (TE = 2.08 or 2.18 ms, TR = 8.01–32.04 ms, FOV = 240–450 × 250–450 mm, Pixel resolution 192–256 × 192–256, Pixel spacing [1.2500;1.2500] – [1.5625;1.5625]). The scans were acquired with both ECG and respiratory gating. The clinical data include part of the clinical assessment of patients in the Great Ormond Street Hospital for Children, London, UK.

fMRI image acquisition has been described in detail previously [1 (link)]. Briefly, gradient-echo T2*-weighted images were acquired using a Siemens Avanto 1.5 Tesla MRI scanner employing a 32-channel head coil (this head coil improves signal-to-noise ratio up to 3.5 times compared to standard 8- or 12-channel coils [26 (link)]). We collected 36 slices per volume, slice gap 1 mm (2 mm slices; 50% distance factor) (see Table 1). The echo planar imaging (EPI) sequence was highly optimised to minimise ventral prefrontal cortex dropout (for extensive sequence details, see previous work [1 (link),25 (link),27 (link)]): echo time = 50 ms, repetition time/slice = 87 ms, slice thickness = 2 mm, in-plane resolution = 2 × 2 mm. One fieldmap per participant per day was acquired using identical parameters to the EPI scans; for each participant, we also acquired one magnetization-prepared rapid gradient-echo T1-weighted 1 mm isotropic anatomical scan.
We used Statistical Parametric Mapping (SPM12; Wellcome Trust Centre for Neuroimaging, London, UK, www.fil.ion.uck.ac.uk/spm) in Matlab R2015a (for the initial region-of-interest (ROI)-based analyses) and Matlab R2018a (for the PPI analyses). All data were slice-time corrected to account for the long repetition time (TR) (3.132 seconds). Preprocessing was identical to that described previously [1 (link)].

Neuroimaging data were acquired using a Siemens Avanto 1.5 Tesla MRI scanner (Siemens, Erlangen, Germany) with 32 channel headcoil and upgraded gradients. Functional imaging involved the acquisition of echo-planar datasets sensitive to BOLD (Blood Oxygen Level Dependent) contrast from axial slices (anterioposterior phase encode direction) tilted 30° from intercommissural plane to minimize T2^* signal dropout from orbitofrontal and anterior temporal regions. Thirty-five 3 mm slices with a 0.75 mm interslice gap provided full brain coverage with an in-plane resolution of 3 × 3 mm (TE 42 ms, volume TR 2.620 ms). Following acquisition of the functional dataset, full brain T1-weighted structural scans were acquired from each participant (MPRAGE, 0.9 mm3 voxels, 192 slices, 1160/4.24 ms TR/TE, 300 ms inversion time, 230 × 230 mm2 FOV).

CEUS and MRI imaging will take place at baseline, one week and four weeks after IRE ablation in order to assess lesion size and enhancement. Furthermore, this will reveal possible complications and any unexpected abnormalities as a result of the IRE procedure that may affect the final surgery (radical nephrectomy).
Contrast enhanced ultrasound (CEUS) utilizes a contrast agent to increase echogenicity of blood for better visualisation tissue vascularisation. Ultrasound contrast contains 3–5 μm microbubbles surrounded by a phospholipid shell. Early studies have shown promising results for the use of CEUS in the follow-up after cryoablation [26 (link)]. This study uses a Philips iU22 (Philips Healthcare, Bothell, USA) ultrasound device which is optimised for contrast studies, in combination with SonoVue (Bracco, Milan, Italy) a third generation ultrasound contrast agent with a elimination half-life of 6 min [27 ].
MRI will be performed using a Siemens Avanto 1.5 Tesla MRI scanner (Siemens Healthcare, Erlangen, Germany) with a 16-channel body array coil. The MRI protocol will include at least the following sequences: T2-trufi with fat suppression, T1-fl2d contrast enhanced in and out of phase, T2-haste, T1 vibe unenhanced and dynamic series at 30 seconds, 60 seconds, and 15 minutes. As MRI contrast agent Gadovist 1.0 (Bayer Pharma, Leverkusen, Germany) will be used.

Cardiac MRI scans were obtained at 2–7 days as well as 12 weeks post‐myocardial infarction with a Siemens Avanto 1.5 Tesla MRI scanner, using a phased array body coil combined with a spine coil. Intravenous gadobutrol contrast (Gadovist, Bayer Schering Pharma AG, Berlin, Germany) was administered at a dose of 0.1 mmol/kg and, after 10 minutes, short axis end‐diastolic late gadolinium enhancement images were obtained. All analysis was performed using validated cardiac MRI analysis software (cvi42, Circle Cardiovascular Imaging Inc., Calgary, Canada) as previously described.16