[Microcirculatory bed of the human trigeminal nerve]

Studies of film preparations from the sheaths of the human trigeminal nerve impregnated with silver nitrate demonstrated all the parts of the microcirculatory bed to be situated in the soft sheath of the root, in the capsule and stroma of the trigeminal ganglion, in epineurium and in the outer layers of perineurium of the nerve branches. In the internal layers of perineurium, pericapillaries, capillaries and postcapillaries are present; in the sheaths surrounding the root fibers and in endoneurium, there are only capillaries. Ontogenic peculiarities in the microcirculatory pathways of the trigeminal nerve are noted; varieties in arterio-venular anastomoses are described. The data obtained and those available in literature make it possible to conclude that the circulatory bed of epineurium and the external layers of perineurium possess the greatest compensatory-adaptive resources. The microcirculatory bed of the internal layers of perineurium and, especially, those of endoneurium possess the least compensatory resources.