Here is a very useful schematic illustration of the intracranial fluid compartments, which may help visualize some concepts in CNS drug delivery.
- Arrows = direction of CSF flow
- Broken arrows = where diffusion may occur between brain, blood vessels, CSF, tissue
- (a) across BBB
- (b) across choroid plexus
- (c) across ependyma
- (d) across pia-glial membranes (brain or spinal cord surface)
- (e and f) across cell membranes of neurons and glial cells
Nau, R., F. Sorgel, and H. Eiffert. “Penetration Of Drugs Through The Blood-Cerebrospinal Fluid/Blood-Brain Barrier For Treatment Of Central Nervous System Infections”. Clinical Microbiology Reviews 23.4 (2010): 858-883.