Emissary veins passing through the foramen ovale, jugular foramen, foramen lacerum, and hypoglossal canal. Because the emissary veins are valveless, they are an important part in selective brain cooling through bidirectional flow of cooler blood from the evaporating surface of the head. In general, blood flow is from external to internal but the flow can be altered by increased intracranial pressure. A type of emissary vein goes through the sphenoidal emissary foramen inferior to the zygomatic arch with the cavernous sinus on the inside of the skull. This is an important route for spread of infection because cranial nerve VI and the
Drug delivery to the brain permeability was known and labeled them either CNS+ or CNS- for compounds that easily transverse the barrier and those that did not. They then set out to analyze the above factors to determine what is necessary to transverse the blood–brain barrier. What they found was a little surprising; lipophilicity is not the leading characteristic for a drug to pass through the barrier. This is surprising because one would think that the most effective way to make a drug move through a lipophilic barrier is to increase its lipophilicity, it turns out that it is a complex function of all of