The posterior perforated substance is a layer of gray matter that is located in the interpeduncular fossa. It is triangular. Its base corresponds to the corpus albicans, its apex to the pons, and its sides to the crus cerebri. It gives passage to the posteromedian ganglionic branches of the posterior cerebral and posterior communicating arteries. Its upper portion assists in forming the floor of the third ventricle. It contains the interpeduncular ganglion.

Substantia perforata posterior

Substance perforée postérieure