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
Common name Spanish and French companions. The Academy of the Hebrew Language publish from time to time short dictionaries of common name in Hebrew for species that occur in Israel or surrounding countries e.g. for Reptilia in 1938, Osteichthyes in 2012, Odonata in 2015 etc... Common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, trivial name, trivial epithet, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; this kind of name is often contrasted with the scientific name