petrotympaniska

The petrotympanic fissure, also known as the petrotympanic lamina or Glaserian fissure, is a fissure in the temporal bone of the skull. It is located at the junction of the petrous and tympanic parts of the temporal bone, situated between the squamous and mastoid parts. This fissure serves as a passage for several important structures, contributing to the complex anatomy of the middle ear and its connections.

Within the petrotympanic fissure, the anterior process of the malleus and the chorda tympani nerve pass through. The anterior process of the malleus is a projection of the malleus, one of the ossicles in the middle ear responsible for transmitting sound vibrations. The chorda tympani is a branch of the facial nerve (cranial nerve VII) that carries taste sensation from the anterior two-thirds of the tongue and also carries parasympathetic fibers to the submandibular and sublingual salivary glands. The fissure also allows for communication between the tympanic cavity of the middle ear and the infratemporal fossa. Anatomical variations in the size and patency of the petrotympanic fissure can occur, potentially influencing the susceptibility to certain middle ear pathologies.