Welcome NotHealthyEnuf17!!! A cholesteatoma is a benign growth of skin in an abnormal location such as the middle ear. Normally, skin lines the entire ear canal and the outer surface of the eardrum. The outermost layer of skin is actually composed of dead cells which are constantly being sloughed off and expelled with earwax. A major component of these dead cells is a protein called keratin. A cholesteatoma can form in the middle ear in three ways. A perforation of the eardrum occuring because of a chronic infection or direct trauma can lead to a cholesteatoma. The skin over the outer surface of the eardrum can start to grow through the perforation and into the middle ear. Some patients are born with small remnants of skin which become entrapped within the middle ear (congenital cholesteatoma). The third mechanism which his most common involves an improperly functioning eustachian tube. The eustachian tube is a canal which connects the middle ear to the back of the nose. It is responsible for equilibrating middle ear pressure to the pressure in the external environment. This tube is normally collapsed in its resting state and when we swallow or yawn, the muscles around the tube contract and cause the tube to open allowing the influx of air into the middle ear space. When this tube does not work appropriately, a relative negative middle ear pressure is generated and maintained. Over time the intact eardrum begins to retract back toward the inner ear. Eventually a skin-lined sac forms which continues to grow and cause infection and bony destruction. The problem occurs when the dead cells accumulate in the middle ear and can not be expelled. Typically an infection occurs with intermittent drainage from the ear. As this ball of dead cells accumulates it produces enzymes which cause the destruction of bone. Go to this page to see a picture of the Progression of a Cholesteatoma. Post edited by: MotherofBoys, at: 10/08/2008 11:46 |
