Petrositis is an inflammation of the temporal bone, the bone covering the ear adjoining the skull. This inflammation reaches deep in the inner ear. It is often linked with otitis media (middle ear infection).

Petrositis Anatomy

The petrous temporal bone is connected with the mastoid and its airways. It has several air chambers within it, and this coupled with its highly vascular marrow that goes to say it is at high risk to infection proceeding toward mastoid from the middle ear.

The petrous temporal bone is associated with important neurological and vascular tissues in the middle cranial fossa, so infection may be damaging at times.

Causes of Petrositis

  • Infection occurs due to S. aureus, S. pneumoniae, H. influenzae, or Pseudomonas spp.; and leads to obstruction of the air tissue system due to inflammation, or other traumas of the mastoid.
  • At times, tuberculosis may be the cause of the infection particularly if the patient is under 20 years of age.

Symptoms of Petrositis

The disease may present a severe or chronic course. In the acute type there is a rapid onset of symptoms preceded by obstruction and pressure in the air ways of the petrous temporal bone.
The symptoms of petrositis, also termed as Gradenigo's syndrome may encompasses:

  • Otorrhoea
  • Fever
  • Acute retro-orbital pain, headache or facial pain
  • Otalgia
  • Confusion, troubled consciousness or coma
  • Other cranial never palsies, specifically trigeminal, facial and vestibulocochlear
  • Seldom there may be signs of dysfunction due to palsies of the Xth cranial nerve or IXth cranial nerve

Nevertheless, it is now rare (due to the advent of antibiotics) for the infection to reach the dura and result in abducens nerve paralysis.

Differential Diagnosis

  • Petrous apex outburst without infection
  • Cholesterol tumor in the petrous temporal bone
  • Sac in petrous temporal bone
  • Langerhans' cell histiocytosis
  • Chondroma and cancer of petrous temporal bone (exceedingly rare)
  • Tumor on petrous temporal bone
  • Extension of Schwannoma
  • Metastatic carcinoma influencing the petrous temporal bone
  • Arachnoid cysts of petrous apex
  • Chordoma of the petrous temporal bone

Exams and Tests for Petrositis

  • Fluid from otorrhoea is recommended for culture and sensitivity testing
  • Fluid from the middle ear can also be taken by myringotomy, for culture and sensitivity testing
  • FBC - may manifest leucocytosis
  • ESR or CRP - may be increased
  • U&E and blood glucose may offer signs as to underlying reasons of enhances risk to infection viz., diabetes, renal failure or other metabolic disorder
  • CT/MRI and Single-Photon Emission Computed Tomography (SPECT) may be facilitated to offer detailed images of the petrous temporal bone and reach to conclusions pertaining to the nature of any pathology in that portion, with minute diagnosis by an experienced radiologist.
  • Radioisotope bone scan
  • A biopsy of the petrous apex may be recommended but rarely
  • Audiometry is often utilized to quantify and check any hearing loss

Medications for Petrositis

Now traditional therapy is administered generally in the shape of intravenous antibiotics based on culture and sensitivity testing.


Surgical approach may be imperative for patients whose symptoms and not responding to antibiotics, or who are developing complications from the infection like cranial nerve problems, venous sinus thrombosis or abscess production.

  • A number of surgical approaches can be considered. In most patients a transmastoid surgery will enable the petrous to be flushed out through the temporal bone. This engages a complete mastoidectomy.
  • Some surgeons also put a drain from the infected area into the mastoid or hypotympanum, to remain the drainage pathway unobstructed and ward off recurrence of the infection.
  • Sometimes more complicated surgical application may be recommended where the response to therapy is insufficient or there is reason to suspect some other cause of a petrous apex trauma.


  • Cranial nerve palsies along with sensorineural conductive deafness
  • Dural venous sinus thrombosis
  • Bony destruction and wearing down
  • Carotid vein spasm and rupture or septic emboli to the brain
  • Meningitis or several intracranial abscesses
  • Brain damage and sometimes even death

 Prognosis of Petrositis

Initially the prognosis was very dissatisfying with death a common occurrence. It is tough to be confident of modern results due to the rarity of the illness:

  • Outlook has definitely improved in the antibiotic years, and most case reports explain successful therapy using with antibiotics and myringotomy/further surgery.
  • Albeit, unsuccessful results or undetected cases are unlikely to be reported, and there is possibly still a prominent morbidity with right low-level mortality due to the condition.
  • Cranial nerve paralysis is supposed to resolve over a few weeks after antibiotic therapy.
  • Hearing loss is sometimes a sequela, but series manifesting outcomes after treatment for several petrous apex traumas display that most retain good hearing.


Using right antibiotics for recommended time period in cases of severe otitis media, where they are felt to be uses, may assist to ward off chronic manifestations because of  partially treated mastoiditis.