CASE REPORT Lateralization of the Epithelium Due to False Epithelial Migration Within Open Mastoidectomy Cavities*

286 Two patients who had been previously treated with radical mastoidectomy procedure were found to have an abnormal small cavity due to a soft, tumor like tissue obstructing the entrance of mastoidectomy cavity on follow-up examination. These tissues were easily perforated by simple instrumentation and observed to be an epithelium with varying thickness. Histologic examination revealed granulation tissue composed of cholesterol clefts, multinucleated giant cells and lymphocytes beneath keratinized squamous epithelium. Open mastoid cavity remains a problem for some patients due to recurrence of inflammatory processes, persistent ear discharge, wax accumulation, fungal infection and granulation tissue formation, requirement of regular medication. In this report, we describe another open cavity problem, lateralization of epithelium due to false migration which may occur after canal wall down mastoidectomy. It may decrease hearing and misleadingly seem like a tumor or a naturally narrowed cavity. Furthermore, it may hide some pathologies like cholesteatoma recurrence. We think that this problem is the result of false epithelial migration probably over a blood clot which was not cleansed due to poor postoperative care.