Vasa nervorum

Vasa nervorum are small arteries that provide blood supply to peripheral nerves. These vessels supply blood to interior parts of nerves and their coverings.

Small vessels like vasa vasorum and vasa nervorum are particularly susceptible to external mechanical compression. A decrease in blood flow through the vasa nervorum has been implicated in the development of diabetic neuropathy. Arteritis of the vasa nervorum leads to mononeuritis multiplex or polyneuropathy. Occlusion of vasa nervosum at level of epineurial arterioles leads to ischemia of nerves leading to vasculitic neuropathy. and has been implicated as cause in few cases of facial nerve paralysis. During invasive diagnostic or therapeutic procedures, injecting a vasoconstrictor close to nerve can reduce perfusion to its supplying vessel, risking ischemic nerve injury.

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