Salivary Gland Choristoma of the Middle Ear and Review of the Literature

Conductive hearing loss due to middle ear masses is uncommon and usually diagnosed after biopsy. We present a case of a permanent facial palsy occurred following an uneventful biopsy during an exploratory tympanotomy in a salivary gland choristoma of the middle ear. Most salivary gland choristomas have been found in the head and neck. Its location in the ear is extremely rare, and thus we present the 38th case in English and non-English literature from the first publication by Taylor in 1961. Complete surgical removal of salivary gland choristomas of the middle ear is indicated when may not result in permanent damage to the facial nerve. Only biopsy and observation are recommended when the mass is intimately associated with the facial nerve or there are unsafe facial nerve abnormalities. Although the facial nerve is involved in 40% of cases, transient or even permanent facial palsies are exceptional. The reactivation of latent herpes virus in the facial canal may be involved in facial palsy’ etiology following minimal and uneventful middle ear surgery like a biopsy rather than nerve injury related to facial canal malformations.