Fig. 1.

Magnetic resonance diagnosed as normal. T1 in axial plane (a) and FSE T2 with fat saturation in the axial plane (b) and coronal plane (c) of thickness 5 mm. The piriform muscles (*) are symmetrical, without alterations to the T2 signal. The sciatic nerves (arrows) present preserved thickness and signal intensity, without obliteration of the perineural fat. The accessory muscle belly of the left piriformis muscle (arrowhead) is best seen on magnetic resonance neurography (d) of thickness 1 mm.