Atypical keratosis obturans.

Keratosis obturans is a rare condition characterized by the accumulation of desquamated keratin material in the bony portion of the external auditory canal. Classically, it is reported to present with severe otalgia, conductive deafness and global widening of the canal. A case of keratosis obturans is described in which the principal symptom was a metallic taste and the main finding was extensive erosion of the hypotympanum with exposure of the facial nerve and the annulus of the tympanic membrane. This presenting symptom and resorption pattern are atypical of keratosis obturans and have not been documented previously.