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URL of this page: //medlineplus.gov/ency/imagepages/2298.htm
Mastoiditis - side view of head
Overview
Mastoiditis is an infection of the bony air cells in the mastoid bone, located just behind the ear. It is rarely seen today because of the use of antibiotics to treat ear infections. This child has drainage from the ear and redness (erythema) behind the ear over the mastoid bone.
Review Date 4/29/2026
Updated by: Ashutosh Kacker, MD, FACS, Professor of Clinical Otolaryngology, Weill Cornell Medical College, and Attending Otolaryngologist, New York-Presbyterian Hospital, New York, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.