The aim of this educational exhibit is to: 1. emphasize the usefulness of MRI in the etilogic diagnosis of brain abscess (BA) as an alternative and/or complementary method to the time consuming and often sterile routine culture procedures; 2. provide a comparative evaluation of the most frequent etiological types of BA – pyogenic (aerobic and anaerobic), tubercular, fungal and parasitic BA - with MRI, ponting out their different behaviors in term of morphological aspects – environment/home invasion and structure – and non morphological aspects -...

Cerebral abscess is a localized infection of the central nervous system (CNS). BA represents a significant medical problem, accounting for 8% of brain occupying space lesions, with recent rise incident due to the exponentially increasing number of immunocompromised patients. The main etiological pathogens of BA are pyogenic bacteria – aerobic and anaerobic; Tuberculosis Mycobacteria; fungi (Aspergillus and Criptococcus); parasites (Toxoplasma and Cistycercus). The most common sources of BA are direct or indirect cranial infection arising from the paranasal sinuses, middle ear, and teeth. Other routes...

Etiologic imaging of BA with MRI 1. MORPHOLOGICAL ASPECTS Environment/Home invasion - Bacteria BA is caused by cerebral dissemination of bacteria coming from neighbouring infections (i.e. in temporal lobe or cerebellum for BA secondary to middle hear otitis) or by hematogenous spread, located at the gray-white matter junction in the distribution of the anterior or middle cerebral arteries. - Tuberculous BA, suspected in immunocompromised patients or in patient with a pulmonary TBC, is spread in cerebral and cerebellar hemisphere, often associated with tubercular meningitis that...

The combined use of morphologic and non-morphologic MR techniques is effective in diagnosing BAs and in etiologic diagnosis. Between the non-morphologic sequences, MR spectroscopy provides a metabolite patterns that may be particularly useful for etiologic categorization.

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