Cranial CSF fistula

Key concepts

● suspect in posttraumatic otorrhea/rhinorrhea or recurrent meningitis

● management strategy:

1) confirm the fluid is CSF

2) identify the site of origin of the leak

3) determine the etiology/mechanism

● most bedside tests are unreliable and include: “reservoir sign,” target/halo sign, qualitative glucose

● the most accurate confirmatory test is β2-transferrin

● CT cisternography is the test of choice for localizing site of the fistula

Non-traumatic CSF leak may be spontaneous in the absence of obvious cause, such as skull base abnormalities or bone erosion related to tumors or hydrocephalus 1) 2) 3).

1)
Ommaya AK. Cerebrospinal Fluid Rhinorrhea. Neurology. 1964;14:106–113.
2)
Clark D, Bullock P, Hui T, et al. Benign intracranial hypertension: a cause of CSF rhinorrhoea. J Neurol Neurosurg Psych. 1994;57:847–849.
3)
Yang Z, Wang B, Wang C, et al. Primary spontaneous cerebrospinal fluid rhinorrhea: a symptom of idiopathic intracranial hypertension? J Neurosurg. 2011;115:165–170.