Table 5 Overview of the 20-min MRI examination. The sequences are listed in the scan order and highlighted in bold text. The imaging markers stemming from the individual sequences are listed in the last row. The body-composition profiling sequences (BCP) differ depending on abdominal or thigh coverage; in the abdominal sequences visceral adipose tissue (VAT) and abdominal subcutaneous adipose tissue (BCP) volumes as well as spinal erectors fa-free muscle volume (FFMV) and muscle fat infiltration (MFI) are measured. In the thigh sequences thigh FFMV and MFI are measured. The liver proton density fat fraction (PDFF) is measured using the mDixon quant sequence. The T2* liver sequence can be used to measure liver iron content (LIC). The dynamic Dixon sequences taken at 0,45,70,180 after bolus injection of gadoterate meglumine (Dotarem®) can measure signal intensity (SI) contrast based hepatobiliary markers. Lastly the two MRE sequences can measure the liver stiffness (|G*|)
Sequence Name | BCP-Abdomen | BCP-Thigh | mDixon Quant | T2* Liver | mDixon Dynamic | MRESE | MREGRE |
|---|---|---|---|---|---|---|---|
Mode | T1-weighted | T1-weighted | Quantitative Imaging | T2-weighted | Dynamic Imaging (0/45/70/180 s) | MR Elastography | MR Elastography |
TR/TE (ms) | “shortest”/1 (3.4/0.98) | “shortest”/"shortest” (3.5/1.13) | “shortest”/"shortest” (6.9/0.96) | “shortest”/2.30 (8.2/2.3) | “shortest”/"shortest” (3.2/1.14) | 1000/53.84 | 50/"shortest” (50/20) |
Echo-train length | 2 | 2 | 6 | N/A | 2 | 1 | 1 |
Flip angle (°) | 10 | 10 | 3 | 10 | 10 | 90 | 30 |
no. slices | 37 | 71 | 77 | 37 | 131 | 4 | 4 |
FOV RL/AP/FH (mm) | 530/371/222 | 540/368/284 | 400/350/231 | 530/371/222 | 380/312.14/229.25 | 370/314.5/43 | 450/403.1/43 |
ACQ voxel size RL/AP/FH (mm) | 3.3 × 3.6 × 6 | 2 × 2.2 × 4 | 3 × 2.99 × 3 | 2.20 × 3.59 × 6 | 1.75 × 1.75 × 3.5 | 4.67 × 4.67 | 1.5 × 4.67 |
ACQ matrix size | 160 × 104 | 264 × 167 | 132 × 118 | 240 × 102 | 216 × 178 | 80 × 66 | 300 × 86 |
Reconstruction matrix | 160 | 288 | 192 | 240 | 448 | 320 | 384 |
NSA | 1 | 1 | 1 | 1 | 1 | 1 | |
Breath hold | “yes” | “no” | “yes” | “yes” | “yes” | “yes” | “yes” |
Compressed SENSE | “no” | “no” | “no” | “no” | “yes” (4) | “no” | “no” |
Imaging marker(s) | VAT, ASAT, liver volume, spleen volume, spinal erectors, FFMV and MFI | Thigh FFMV and MFI | PDFF | LIC | SI | (|G*|) | (|G*|) |