Otogenic Intracranial Abscesses, Our Experience Over the Last Four Decades

Abstract

OBJECTIVE:To evaluate the predisposing factors for otogenic intracranial abscesses, assess their changes over time, and analyze how they differ from those due to other causes. MATERIALS and METHODS:The medical records of all patients treated for otogenic intracranial abscesses, between 1970 and 2012 at a tertiary referral center, were retrospectively analyzed. The analysis included patient demographics, clinical characteristics, causative pathogens, treatments, outcomes, and comparisons of otogenic and non-otogenic intracranial abscesses. RESULTS:Of all intracranial abscesses, 11% (n=18) were otogenic. In the 1970s, otogenic infections were a common predisposing factor for intracranial abscess; but within our study period, the incidence of otogenic intracranial abscesses decreased. Most (94%) otogenic cases were due to chronic suppurative otitis media and 78% were associated with cholesteatoma. Most patients (94%) had ear symptoms. The most common presenting symptoms were discharge from the infected ear (50%), headache (39%), neurological symptoms (28%), and fever (17%). The most common pathogens belonged to Streptococcus spp. (33%), Gram-negative enteric bacteria (22%), and Bacteroides spp. (11%). Neurosurgery was performed on all patients, 69% of which were prior to a later ear surgery. Surgery of the affected ear was performed on 14 patients (78%). A favorable recovery was typical (78%); however, one patient died. CONCLUSION:Otogenic intracranial abscesses were most commonly due to a chronic ear infection with cholesteatoma. Ear symptoms and Gram-negative enteric bacteria were more common among patients with otogenic than non-otogenic intracranial abscesses.

Cotton bud in external ear canal causing necrotising otitis externa and subdural abscess

“…A far more common mechanism for infection to spread from the ear to the central nervous system to cause intracranial abscess is via a breach in the tegmen tympani due to suppurative otitis media, causing 94% of otogenic intracranial abscess and complicating approximately 0.26% of cases of suppurative otitis media 6 7. Temporal lobe abscess has also been described in a patient with ectodermal dysplasia 8.…”

Recurrent Otogenic Intracranial Sepsis: A Key Radiological Finding, Not to Be Missed

“…There are various theories postulating why these defects occur, with suggestions that this could be due to constant cerebrospinal fluid (CSF) pressure, CSF from aberrant arachnoid granulation tissue causing pressure on the bone, idiopathic intracranial hypertension, and morbid obesity [4]. This was likely the cause for the recurrent episodes of severe intracranial sepsis that our patient suffered as it is a well-known risk factor for intracranial infections [3].…”

“…Infection may also spread to the temporal bone causing mastoiditis. Unresolved otitis media can lead to intracranial extension of infection, leading to intracranial sepsis, manifesting itself as meningitis, brain abscess, or lateral sinus thrombosis [2, 3].…”

Otogenic abscess: rarity and reality

“…Middle ear with mastoid erosion leads to collection of pus between the dura and cranium. It gets collected around the lateral sigmoid sinus and due to low host immunity leads to sigmoid sinus thrombosis which may extend down to involve internal jugular vein; it may further lead to complication of pulmonary embolism, ultimately leading to pulmonary infarct which due to early treatment is rare nowadays [5,8,9,10].…”