MRI
Axial T2
Coronal T1
Axial STIR
Axial T1
Coronal STIR
Axial Gradient Echo
Axial T1 fat sat
Axial T1 C+ fat sat
Coronal T1 C+ fat sat
Sagittal T1 C+ fat sat
Multiloculated fluid collection of the right iliacus muscle (volume ~ 90 mL). It displays an iso- to high signal to the normal muscles on T1, high signal on T2 and STIR with peripheral enhancement, fat stranding and thickening with enhancement of the adjacent peritoneal reflections. Oedematous infiltration of the right erector spinae and quadratus lumborum muscles as well as the internal oblique and transversus abdominis muscles (myositis).