Hearing anomalies following radiation therapy for head and neck cancers.

Ionizing radiation used for the treatment of head and neck tumors affected epithelial and connective tissue. Epithelial lining of the middle ear mucosa desquamated, when exposed to conventional dose of radiation. Mucosa becomes oedematous which subsequently lead to formation and collection of sterile fluid within middle ear cavity and thus producing radiation otitis media with conductive deafness. Radiation induced changes in the structure surrounding the end organs of hearing such as vascular and connective tissue alterations which later eventually could affect the end organ leading to perceptive type of hearing loss as a result of chronic anoxia to end organ.