Petrotympanic fissure


The petrotympanic fissure (also known as the squamotympanic fissure) is a fissure in the temporal bone that runs from the temporomandibular joint to the tympanic cavity.
The mandibular fossa is bounded, in front, by the articular tubercle; behind, by the tympanic part of the bone, which separates it from the external acoustic meatus; it is divided into two parts by a narrow slit, the petrotympanic fissure.