Dilated Epidural Venous Plexus

These images show multiple prominent serpiginous T1 and T2 hypointense structures in the ventral epidural space posterior to the L4 and L5 vertebral bodies resulting in mass effect on the thecal sac with crowding of the cauda equina.This is most compatible with dilation of the epidural venous plexus in this pregnant patient. Mass effect from the gravid uterus results in redirection of venous flow through collateral of the vertebral plexus. This is usually a reversible phenomenon and shouldn’t be confused for epidural hematoma or a vascular malformation.