The anterior epitympanic recess: CT anatomy and pathology

To describe the variation in size and shape of the anterior epitympanic recess and to discuss pathologic processes that affect this space.

Axial CT scans of the temporal bones of 31 adults and 19 children were reviewed retrospectively to ascertain the morphology and size of the anterior epitympanic recess. Selected confirmed disease processes involving this space were studied.

The anterior epitympanic recess, which is consistently identified on axial CT scans, is either single or multicelled. In our study, it was made up of a solitary cell in 61 of 100 ears. Side-to-side symmetry in shape was present in 78 of 100 cases. The size of a solitary air cell ranged from 1.0 to 7.0 mm.

The configuration of the anterior epitympanic recess is readily affected by a persistent stapedial artery, by facial nerve schwannomas, by hemangiomas of the facial nerve canal in the geniculate region, and by congenital and acquired cholesteatomas. Familiarity with the CT anatomy of this space facilitates recognition of these pathologic processes at an early stage.