OSTEOMA GROWING FROM THE MASTOID CORTEX

Osteoma in the region of the mastoid is believed to be a rarity. It can be classified as a true osteoma, or bony neoplasm, rather than as an exostosis or hyperostosis. The osteoma seen by the otolaryngologist is usually in the lumen of the frontal sinus or in the ethmoid capsule. A hurried and incomplete search of the literature and personal communications from a number of pathologists and otologists confirm the impression that few reports of similar growths in the region of the mastoid cells have been made. REPORT OF A CASE J. K., aged 39, an executive in an insurance company, in 1927 had his attention called by his barber to a painless swelling on the left side of the head, behind the ear and just within the hair line. He was unable to associate any trauma with this growth, there was no pain and the skin over the