Skull Base Osteomyelitis

Skull Base Osteomyelitis
Panel discussion
Dr Mohsen Rajati
Panelists: A. Asadollahi,S. Dabiri,F. Farahani, MA. Kazemi

Skull base osteomyelitis or Malignant otitis externa (MOE) is a progressive, life-threatening infection of the temporal bone that can spread to the neighboring areas of the skull base. The causative agents are Pseudomonas aeruginosa, methicillin-resistant Staph. Aureus (MRSA), and also fungal species. MOE commonly affects elderly, diabetic, and immunocompromised patients.

Common presenting symptoms of MOE include otalgia, otorrhea, aural fullness, and hearing loss, which are also seen in ordinary forms of otitis externa; and this can make diagnosis difficult and may lead to a delay in treatment. More advanced cases of Skull base osteomyelitis may present with cranial neuropathies including facial nerve palsy. Involvement of cranial nerves is an ominous sign that is associated with higher rates of mortality.

Laboratory tests such as cultures, and imaging investigations including CT scan, MRI and Radionuclide exam (technetium/ gallium scintigraphy) are important paraclinical tools to diagnose the disease and to determine the gravity of the condition.

Patients are mostly managed in the hospital with IV antibiotics and medical care of their underlying co-morbidities. On rare occasions upon failure of medical managements surgery is indicated to debride the resistant infective tissues. The panel is to address various existing controversies on the clinical and paraclinical issues related to skull base osteomyelitis.