Fig. 1. Magnetic resonance imaging of the pelvis. (A) Swelling of the left sciatic nerve (white arrow) from the sciatic foramen to the proximal thigh compared with the right sciatic nerve on an maximum intensity projection image from a coronal reconstructed three-dimensional-short tau inversion recovery sampling perfection with application optimized contrasts with variable flip-angle image. (B) Increased signal intensity in the bilateral external/internal oblique abdominis (white arrow) and left psoas muscle (asterisk) on an axial T2-weighted image with TSE fat suppression. (C) Diffuse swelling of the left sciatic nerve (white arrowhead) surrounded by diffuse edema and high signal change in the left gluteal muscle (white arrow) compared with only a focal signal change near the ischial tuberosity of the right gluteal muscle (white arrow) on an axial T2-weighted slice with TSE fat suppression. (D) Increased signal intensity in the right pectineus (white arrow) and left quadratus femoris muscles (white arrow).

TSE = turbo spin echo.