“…CSF outflow was shown to drain within sheaths of cranial nerves to reach extracranial lymphatics and collecting lymph nodes (LNs) in the neck (McComb, 1983;Bradbury and Cserr, 1985;Koh et al, 2005). In addition, elegant imaging approaches using near-infrared or dynamic contrast-enhanced magnetic resonance (Ma et al, 2017(Ma et al, , 2019) also showed CSF bulk outflow into extracranial lymphatic pathways that proceeds through the basal cisterns, which are the expansions of the subarachnoid space prolonging around cranial nerves and intracranial vessels (Altafulla et al, 2019). However, an additional contribution of dural lymphatics to CSF drainage was revealed by tracer injections into the CSF, which were taken up by MLVs (Antila et al, 2017;Louveau et al, 2018;Hsu et al, 2019;Ahn et al, 2019).…”