MRI/myelographic localization of fistulous tract in spinal dural arteriovenous malformations prior to arteriography

Spinal Dural Arteriovenous Fistula: Imaging Features and Its Mimics

Spinal dural arteriovenous fistula (SDAVF) is the most common spinal vascular malformation, however it is still rare and underdiagnosed. Magnetic resonance imaging findings such as spinal cord edema and dilated and tortuous perimedullary veins play a pivotal role in the confirmation of the diagnosis. However, spinal angiography remains the gold standard in the diagnosis of SDAVF. Classic angiographic findings of SDAVF are early filling of radicular veins, delayed venous return, and an extensive network of dilated perimedullary venous plexus. A series of angiograms of SDAVF at different locations along the spinal column, and mimics of serpentine perimedullary venous plexus on MR images, are demonstrated. Thorough knowledge of SDAVF aids correct diagnosis and prevents irreversible complications.

Engorged and tortuous intradural filum terminale vein as a sign of a sacral dural arteriovenous malformation

Sacral spinal dural arteriovenous (AV) malformation is rare and its clinical features are not specific to differentiate sacral dural AV malformation from the superiorly located ones. A sacral dural AV malformation, therefore, is usually diagnosed after negative thoracic and lumbar arteriograms. In this report, we propose a myelographic or magnetic resonance (MR) sign of engorged and tortuous intradural filum terminale vein as an indication of a sacral dural AV malformation. When this sign is seen, pelvic arteriography should be performed first.