Middle Ear

Case A: CT of the temporal bone demonstrates a soft tissue mass ( arrow ) just anterior to the cochlear promontory and contiguous with the tympanic membrane. The mass abuts the tip of the malleus manubrium. No evidence of communication with the carotid artery or jugular vein is found.

Case B: CT of the temporal bone demonstrates an irregular, infiltrative, soft tissue mass centered within the right jugular foramen ( J ), with superolateral extension ( arrow ) into the middle ear cavity and mastoid air cells. Evidence is found of permeative bony destruction of the lateral plate of the jugular fossa with extension into the middle ear. The auditory ossicles and scutum are intact.

Case C: CT of the temporal bone demonstrates an aberrant course of the ICA ( C, arrow ) in the middle ear. The distal C1 (cervical) segment is absent, with an anomalous connection passing laterally and anteriorly over the cochlear promontory to join the C2 (petrous) segment in the carotid canal. The carotid artery abuts the tip of the malleus manubrium at its lateral aspect.

Case D: CT of the temporal bone demonstrates a well-circumscribed, rounded, soft tissue opacity ( arrow ) within the middle ear. This opacity projects just posterior and inferior to the cochlear promontory and contacts the tympanic membrane. The auditory ossicles are laterally displaced but intact. The Prussak space and the remainder of the middle ear cavity are spared.