Drain ‘pipes’ behind the nose clear cerebrospinal fluid from the brain

This study reveals a distinctive network of lymphatic vessels at the back of the nose that serves as a major hub for the outflow of cerebrospinal fluid (CSF) to deep cervical lymph nodes in the neck. These deep cervical lymphatics remain intact with ageing, and their pharmacological activation enhanced CSF drainage in mice.

Source:  Nature

An excerpt from the original paper:

"Among the known routes for CSF drainage from the subarachnoid space are lymphatics in the cribriform plate, where olfactory nerves pass through the ethmoid bone, and in the perineurium of cranial nerves.   Lymphatics in the dura mater also function as a CSF drainage route.However, despite solid documentation of the contribution of lymphatics to CSF clearance, the connections between the subarachnoid space and extracranial lymphatics involved in CSF clearance have been challenging to elucidate.

The importance of evidence for the nasopharyngeal lymphatic plexus functioning as a CSF outflow hub is highlighted by its regression during ageing. Yet, the ageing-resistant pharmacological activation of deep cervical lymphatic transport towards lymph nodes can still increase CSF outflow, offering an approach for augmenting CSF clearance in age-related neurological conditions in which greater efflux would be beneficial."

Source: Nature