Cerebrospinal fluid rhinorrhea
CSF fistulae provide a route of intracranial access for a variety of microorganisms and are an important risk factor for ascending infection, with complication by bacterial meningitis accounting for the majority of morbidity in patients with active CSF rhinorrhea at an estimated annual risk of approximately 10%. Less frequently, larger skull base defects can lead to meningoencephalocele and/or pneumocephalus and secondary brain compression.
G96.0 – Cerebrospinal fluid leak
85638002 – Cerebrospinal fluid rhinorrhea
- Common rhinopathies (eg, seasonal allergic rhinitis, vasomotor rhinitis) – Present with associated signs and symptoms of mucosal congestion; rhinorrhea is usually bilateral.
- CSF otorhinorrhea – There will be ipsilateral middle ear effusion.
- Retained sinonasal irrigation fluid
- Because many CSF leaks are intermittent, failure to reproduce CSF rhinorrhea in the office does not rule out the diagnosis, particularly when the history is otherwise strongly suggestive.
- A CSF fistula may mask underlying intracranial hypertension by virtue of acting as a release value that decompresses the subarachnoid space. As such, normal opening pressure by lumbar puncture in a patient with active CSF rhinorrhea cannot reliably exclude elevated ICP as an etiological factor.