A protruding jugular bulb on CT is seen as a dehiscence of the bony floor of the hypotympanum with a soft tissue mass in the middle ear. A jugular diverticulum is an irregular outpouching of the jugular bulb that rises superiorly and medially in the petrous pyramid. With progression of disease the trabeculae are demineralized and then destroyed forming areas of coalescent suppuration. CT or MRI can be used if a resultant intracranial abscess is suspected. In chronic mastoiditis the trabeculae are thickened and there is nonhomogenous clouding of the air cells.
Some air cells become obliterated while others become filled with granulation tissue and fluid.
As in the mastoid, AOM is evident as air fluid levels and homogenous opacification of the middle ear and mastoid air cells by fluid density. In chronic suppurative otitis media there is clouding of the middle ear space and due to granulation tissue, polyps and pus. The long process of the incus may be eroded and there is some aeration of the middle ear since there is a TM perforation. Tympanosclerosis can show up as plaques. Typically the acquired cholesteatoma arises in Prussak's space and causes bone erosion and medial displacement of the ossicles.