A number of lesions and disease processes have been described within the petrous apex, including cholesterol granulomas, petrous apicitis
, cerebrospinal fluid cysts, encephaloceles, epidermoids, effusions, mucoceles, carotid aneurysms, asymmetric pneumatization, chordomas, chondrosarcomas, metastases, paragangliomas (glomus tumors), meningiomas, and schwannomas, (1-8) Characteristic presenting symptoms, as well as findings on magnetic resonance imaging (MRI) and computed tomography (CT) scans, are essential for differentiation of the lesion.
Other extracranial complications include Bezold's abscess, labyrinthine fistulae, facial nerve paralysis and petrous apicitis
A later coronal-projection CT showed definite bone destruction in the anterior petrous apex, confirming suspicions that a petrous apicitis was responsible for the facial paralysis and abscess.
Petrous apicitis, once a relatively common complication of otomastoiditis, is much less prevalent today, as are other complications of infectious ear disease.
1,2] The occurrence of facial paralysis as a sequela of petrous apicitis has been reported.
In retrospect, the nasopharyngeal abscess had undoubtedly been the egress point for a "silent" petrous apicitis.
It was not until 3 weeks into our patient's second hospitalization that we obtained the coronal CT view of the skull and for the first time had radiologic proof of an apicitis.
Simple fluid effusions can become infected and lead to bacterial petrous apicitis
, osteomyelitis, or chronic obstruction, which in turn can lead to the formation of petrous apex mucoceles.