Brain Trauma
Shown here is the base of the brain and various arteries that supply different regions. The insult that occurred here is occlusion of the posterior communicating arteries (labeled PCoA), which connects two major vessels of the brain: the middle cerebral and the posterior cerebral artery. An important theme in medicine relates differences in the body’s response depending on the degree of insult. For example, when arteries are partially clogged, the body may respond by increasing production of angiogenic factors that may lead to sprouting of new collateral vessels to bypass the partial occlusion, and the tissue that the blood supplies may still be salvaged and retain function. However, in events where the entire vessel becomes occluded [due to clot formation for example], the body cannot respond in time and the tissue dies.
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