Background: The differential diagnosis of radiculomeningeal arteriovenous malformation (AVM) includes spinal intramedullary tumor and spinal cord myelitis. In making the diagnosis of radiculomeningeal AVM, clinical features of the history and magnetic resonance (MR) imaging findings are important initially, followed by selective spinal arteriography with or without myelography to confirm the diagnosis. The differential diagnosis, however, is not always easy.
Methods: We encountered five radiculomeningeal AVM and 14 intramedullary thoracolumbar tumors that were accurately diagnosed preoperatively. We performed postmyelographic computerized tomography (CT) in all five patients with radiculomeningeal AVM and five patients with intramedullary thoracolumbar tumors that were not able to exclude radiculomeningeal AVM with only MR imaging.
Results: In all our patients with radiculomeningeal AVM, postmyelographic CT demonstrated the dilated coronal venous plexus on the dorsal aspect of the spinal cord in contrast with a single swelling of the spinal cord in the patients with intramedullary tumor.
Conclusions: We believe that this finding is useful when the serpentine dilated coronal venous plexus is not clearly identified on myelogram and selective spinal arteriography is not apparently indicated.