Eosinophilic granuloma in the temporal bone.

Eosinophilic granuloma is an uncommon granulomatous disease which can affect the temporal bone. Although initially silent, the disease may erode the mastoid cortex, destroy the tegmen and extend into the cranial vault, as well as erode the semicircular canals or cochlea. These lesions almost always become infected and can be confused with chronic otomastoiditis. Equally important, temporal bone involvement may represent only one manifestation of a multifocal disease. Between 1940 and 1978, 19 cases of eosinophilic granuloma involving the temporal bone have been recorded in the Armed Forces Institute of Pathology Registry. Most recently, a 24-year-old white boatswain's mate was sent to the National Naval Medical Center for treatment of unifocal disease which originated in his right mastoid bone. He subsequently underwent modified radical mastoidectomy and received 2500 R cobalt therapy to the temporal bone following surgery. His case history is detailed and the problem of eosinophilic granuloma in the temporal bone is reviewed in depth.