Lymphatics drain the human central nervous system. It is likely that this is a desirable feature of brain anatomy because of the vulnerability of the CNS caused by a need for vision, smell and hearing. The lymphatic system recruits help from the cellular immune system, which comprises B and T cells, by delivering infected lymph fluid into the blood. Brain sensation risks infection of the brain. The more we smell, see and hear, the greater our risk. High CNS pressure could encourage lymphatic flow by pushing liquid into the nose or periorbital tissue, or if higher, press on delicate lymphatic vessels and occlude them. This means that brain lymphatic flow and CNS pressure will have an unpredictable relationship. That high pressure occurs with occlusion of vessels does not mean that vessel occlusion causes raised pressure. I believe that lymphatic occlusion in the presence of high pressure can be compensated by the autonomic nervous system, so that volume regulation may briefly be more important than lymphatic flow. In the most fortunate cases, lymphatic flow alerts the immune system and autonomic brain regulation and the other body organs maintain CNS equilibrium. This happens with a bad attack of sinusitis. For others the body is overwhelmed, blood pressure cannot be maintained, the spleen is too old or too immature to respond and the brain swells briefly and then dies. This occurs with meningococcal pharyngitis. My assertion is that brain volume regulation is at least as important as the lymphatics, they depend upon each other, but that the lymphatics are in essence subservient.
Fluids and Barriers of the CNS
querry
31 May 2010
Lymphatics drain the human central nervous system. It is likely that this is a desirable feature of brain anatomy because of the vulnerability of the CNS caused by a need for vision, smell and hearing. The lymphatic system recruits help from the cellular immune system, which comprises B and T cells, by delivering infected lymph fluid into the blood. Brain sensation risks infection of the brain. The more we smell, see and hear, the greater our risk. High CNS pressure could encourage lymphatic flow by pushing liquid into the nose or periorbital tissue, or if higher, press on delicate lymphatic vessels and occlude them. This means that brain lymphatic flow and CNS pressure will have an unpredictable relationship. That high pressure occurs with occlusion of vessels does not mean that vessel occlusion causes raised pressure. I believe that lymphatic occlusion in the presence of high pressure can be compensated by the autonomic nervous system, so that volume regulation may briefly be more important than lymphatic flow. In the most fortunate cases, lymphatic flow alerts the immune system and autonomic brain regulation and the other body organs maintain CNS equilibrium. This happens with a bad attack of sinusitis. For others the body is overwhelmed, blood pressure cannot be maintained, the spleen is too old or too immature to respond and the brain swells briefly and then dies. This occurs with meningococcal pharyngitis. My assertion is that brain volume regulation is at least as important as the lymphatics, they depend upon each other, but that the lymphatics are in essence subservient.
Competing interests
none