Anything passing through the petrotympanic fissure
- The chorda tympani passes through it.
- Just before exiting the stylomastoid foramen, the facial nerve enters the tympanic cavity as the chorda tympani from the canaliculus for chorda tympani in the stylomastoid foramen (facial nerve canal) and exits the external surface of cranial base through this petrotympanic fissure. It then joins the lingual nerve. It contains taste nerve fibers and the secretory nerves (parasympathetic nerves) of the submandibular and sublingual glands.