Tympanic membrane retraction caused by erosion of the ossicles (hearing bones). Discharge from the ear often indicates that the retraction pocket has developed into a cholesteatoma. Three factors must occur for the tympanic membrane to become retracted: When gas pressure within the middle ear is less than atmospheric pressure, the eardrum can become sucked into the middle ear space. This is caused by inadequate opening of the Eustachian tube and absorption of air from the middle ear space. People with a patulous Eustachian tube may also cause negative middle ear pressure by repeatedly sniffing to try to keep their Eustachian tube closed. The
Inferior tympanic artery can result in pulsatile tinnitus. The resulting Aberrant Carotid artery can mimic neoplasm on CT. Inferior tympanic artery The inferior tympanic artery is a small branch of the ascending pharyngeal artery. It is a small branch which passes through a minute foramen in the petrous portion of the temporal bone which is called tympanic canaliculus or inferior tympanic canaliculus, in company with the tympanic branch of the glossopharyngeal nerve, to supply the medial wall of the tympanic cavity and anastomose with the other tympanic arteries. In the case of a missing or underdeveloped cervical ICA, the Inferior tympanic artery can