Salivary gland choristoma of the middle ear.

Salivary gland choristoma (ectopic salivary gland tissue) is an unusual condition that occurs in various locations within the middle ear. It is a distinct histopathologic entity that should be differentiated from other epithelial lesions of the middle ear. Since the lesion commonly involves the facial nerve, its recognition is particularly critical to avoid unnecessary severing of the nerve.