Abstract
Material collected from the tympanic cavity before and from the mastoid antrum during operation on 58 discharging ears of patients with chronic otitis media was cultured, and the bacteria in these two cavities were compared. Staphylococcus aureus was the commonest organism in the tympanic cavity and Staphylococcus epidermidis in the mastoid antrum. Anaerobic bacteria were found only in the mastoid antrum of a patient with cholesteatoma. In 32 (55%) of 58 ears examined, bacteria were detected in both tympanic and mastoid cavities. In 17 ears (53%), the bacterial strains in the two cavities differed. The necessity of a bacteriological examination of the mastoid cavity during operation in order to select antibiotics for postoperative treatment is stressed.
