The pathogenesis of acquired attic cholesteatoma remains unclear. Of many theories that have been described so far the most important are the retraction theory, the proliferation theory, the migration theory, and the metaplasia theory. There are many articles in the international literature describing these theories and trying to substantiate them. In 2000, Sudhoff and Tos1 promoted a combination of retraction and proliferation theories in explaining the pathogenesis of attic cholesteatoma. They first described four types of attic retraction (▶ Fig. 12.1: type 0 representing no retraction): ● Type 1: slight retraction with air between Shrapnell’s membrane and the neck of the malleus ● Type 2: retraction down to the malleus neck with possibility of adhesion ● Type 3: retraction behind the scutum with some bone resorption ● Type 4: retraction behind the scutum with considerable bone resorption, making the malleus head and incus body visible.
|Titolo:||Exclusively Endoscopic Treatment of Severe Attic Retraction and Epitympanic Cholesteatoma|
|Data di pubblicazione:||2014|
|Appare nelle tipologie:||02.01 Contributo in volume (Capitolo o Saggio)|