Objective:

To discuss a case of severe intracranial hypotension secondary to CSF-venous fistula, with an emphasis on clinical and radiographic features, pathophysiology, and treatment.

Background:

Case: A 58-year-old woman with remote history of Chiari 1 malformation status post C3-T1 decompression and fusion presented with three weeks of positional headaches followed by acute onset lethargy and encephalopathy. Brain MRI showed crowding of the cerebellar tonsils which can be seen in Chiari 1 malformation, but the presence of acute subdural hematomas, diffuse pachymeningeal enhancement, and effacement of the suprasellar cistern with pituitary enlargement were together highly suggestive of intracranial hypotension from a cerebrospinal fluid (CSF) leak. Spinal MRI showed subdural hematomas at the T5-T9 levels without longitudinal extradural collections, concerning for CSF-venous fistula (CVF). CT myelogram confirmed right-sided CVF at the T1 level. She underwent transvenous embolization of the fistula with resolution of symptoms.

Design/Methods:

NA

Results:

NA

Conclusions:

Spinal CVFs, which are responsible for up to 20% of spinal CSF leaks, are aberrant connections between the spinal subarachnoid space and epidural venous plexus that cause loss of CSF into the venous system. Rarely, resultant intracranial hypotension leads to altered level of consciousness and impending tonsillar herniation, a neurologic emergency. Definitive treatment is endovascular or open repair, but Trendelenburg positioning and intrathecal saline injection via a lumbar drain may serve as temporizing measures. Literature on risk factors for CVFs remains sparse, and it is unclear if our patient’s history of spinal decompression and fusion were related to development of CVF, or whether occult CVF was previously misdiagnosed.