Topographic Localization of Cerebrospinal Fluid-Venous Fistulae

Area of Science:

• Neurosurgery
• Interventional Radiology
• Neuroradiology

Background:

• Spontaneous intracranial hypotension can be caused by cerebrospinal fluid-venous fistulae (CVFs).
• Transvenous embolization (TVE) is an effective treatment, but the precise fistula location is often unclear.
• Current TVE techniques involve extensive embolic casting to ensure fistula obliteration.

Purpose of the Study:

• To determine the imaging-based location of the fistulous point relative to the intervertebral foramen.
• To assess if foraminal topography differs based on CVF morphology (diverticular vs. non-diverticular).

Main Methods:

• Retrospective review of 29 patients with CVF-positive CT myelography.
• Classification of CVFs as diverticular or non-diverticular.
• Mapping of the fistulous point onto a standardized foraminal schematic in three planes.

Main Results:

• Meningeal diverticula were present in 82.8% of cases.
• Diverticula CVFs most often localized to the ventrolateral foramen (71.4%).
• Non-diverticular CVFs most often localized to the ventromedial foramen (60%).
• Most fistulous points (69.0%) were in the anterosuperior foraminal quadrant, irrespective of CVF type.
• Non-diverticular fistulous points were located along the nerve root sleeve (53.3%) or spinal dura (46.7%).

Conclusions:

• CVFs exhibit reproducible foraminal topography that varies by morphology.
• Diverticula CVFs favor ventrolateral locations; non-diverticular CVFs favor ventromedial locations.
• Anterosuperior foraminal quadrant is the most common location across all CVF types.
• These imaging landmarks can guide procedural targeting in TVE and fibrin glue injection.