FIG 3. Axial dynamic CT myelogram at the level of the C7–T1 interspace in the left lateral decubitus (A), right lateral decubitus (B), supine (C), and prone (D) positions demonstrates accumulation of extra-arachnoid contrast material along the left C8 root sleeve (open arrow). The final prone images, which were obtained 30 minutes after injection of contrast material, demonstrate dilution of contrast material in the previously unopacified epidural fluid collection (black arrow). Additional leaks were located at the level of the right T6 root sleeve and along the ventral aspect of the junction of the right T9 root sleeve and thecal sac (not pictured).