Direct Injection of Meningeal Diverticula for Localization of CSF-Venous Fistulas: Technique and Clinical Applications

The recognition of CSF-venous fistulas as a cause of spontaneous intracranial hypotension has increased dramatically in recent years, in large part due to the more pervasive use of lateral decubitus myelography. Lateral decubitus positioning is critical for identification of CSF-venous fistulas, since most of these fistulas arise from meningeal diverticula along the nerve root sleeves. These diverticula must be filled with dense contrast to allow for confident visualization of contrast in veins draining CSF-venous fistulas. Even with excellent technique, decubitus CT or fluoroscopic myelography can fail to detect some CSF-venous fistulas. In this technical report, we describe the use of direct contrast injection into meningeal diverticula for the identification or further characterization of CSF-venous fistulas. This is a potentially useful problem-solving technique that can increase diagnostic confidence for this sometimes-elusive pathology. We have found it useful both to detect CSF-venous fistulas and exquisitely determine their site of origin within meningeal diverticula.