Stony-Dympanic Gap [Fissura Petrotympanica, Pna, Jna; Fissura Petrotympanica (Glaseri), Bna; Syn. Glazerova Shchel]

Petrostympanic fissure: anatomy and functions

The petrotympanic fissure, also known as fissura petrotympanica or Glaser's fissure (after the German anatomist Carl Glaser), is a narrow space between the tympanic part of the temporal bone and the outwardly projecting edge of the roof of the tympanic cavity. This location is an important functional component of the ear because the chorda tympani passes through it, connecting the eardrum to the malleus bone.

Anatomy of the petrotympanic fissure

The petrotympanic fissure has several names, including fissura petrotympanica, pna, jna, fissura petrotympanica (glaseri), and bna. It is located on the posterior wall of the tympanic cavity and has the shape of a triangle with the base located on the tympanic part of the temporal bone and the apex directed to the pathological foramen.

The chorda tympani, passing through the petrostympanic fissure, connects the eardrum to the malleus, which is located inside the tympanic cavity. Together with the other bony elements of the ear, the malleus transmits sound waves from the eardrum to the stapes, which transmits them further into the cochlea.

Functions of the petrostympanic fissure

The petrotympanic fissure plays an important role in transmitting sound waves through the ear. When sound waves hit the eardrum, it begins to vibrate, transmitting vibrations to the hammer. The hammer, in turn, transmits vibrations through the tympanic string to the eardrum, which begins to vibrate even more, amplifying the sound waves.

The petrostympanic fissure is also important for drainage of the tympanic cavity. If inflammation or fluid builds up in this area, it can cause hearing problems. To treat such conditions, a myrionectomy procedure may be used, which involves removing part of the eardrum and creating an opening in the petrotympanic fissure for drainage.

In conclusion, the petrotympanic fissure is an important component of the ear anatomy, playing an important role in the transmission of sound waves and drainage of the tympanic cavity. Understanding its anatomy and functions can help in the diagnosis and treatment of various ear diseases.

In its structure, the petrotympanic fissure is a narrow and winding depression located between the tympanic part of the temporal bone, as well as the protruding outer part of the roof of the tympanic cavity. It is in this place that the exit point for the tympanic ligament is located. Along with the fact that the very concept of a stony gap can have different variants of names - stony or barmy gap, in scientific articles the following version of the definition is most often used - Stony-Tympanic Gap.