Fig 5. Light micrographs in the cauda equina at the site of constriction after 3 weeks (H&E stain).

A, A whole view of cauda equina showing as high intensity on gadolinium-enhanced MR imaging. B, Ventral roots. C, Dorsal roots. Light microscopy revealed congestion and dilation of the radicular veins (B and C, arrows) inside the cauda equina, inflammatory cell infiltration, and Wallerian degeneration (C, asterisks) observed in the entrapped region. This situation reflected breakdown of blood–nerve barrier on fluorescent microscopy and high intensity on gadolinium-enhanced MR imaging.