Table 3.
Assessment of CT and MRI muscle fat infiltration.
| Modality | Muscle fat infiltration | All subjects (N = 50) | Male (N = 31) | Female (N = 19) | P-value | |
|---|---|---|---|---|---|---|
| CT | Mean radiodensity | Total (HU) | 30 ± 12 | 29 ± 15 | 32 ± 6 | 0.828 |
| Right (HU) | 29 ± 13 | 28 ± 16 | 30 ± 7 | |||
| Left (HU) | 31 ± 11 | 30 ± 14 | 33 ± 6 | |||
| P-value | 0.675 | 0.070 | ||||
| MRI | MRIPDFF | Total (%) | 20 ± 8 | 20 ± 9 | 20 ± 4 | 0.090 |
| Right (%) | 20 ± 8 | 20 ± 10 | 21 ± 5 | |||
| Left (%) | 20 ± 7 | 19 ± 9 | 20 ± 4 | |||
| P-value | 0.978 | 0.686 |
CT and MRI muscle fat infiltration were assessed by mean radiodensity in Hounsfield units (HU) and proton density fat fraction (MRIPDFF) in percent (%), respectively. Values are given for the entire (total) paraspinal skeletal muscle compartment as well as each right and left compartment, respectively, for male and female patients as well as the entire study population (N = 50). CT: computed tomography, MRI: magnetic resonance imaging.