REVIEW OF 140 PATIENTS WITH BRAIN-ABSCESS

There were 140 cases of brain abscess treated between 1980 (when CT sc anning became available) and June 1991. These arose by spread of a con tiguous area of infection in 37%, and from another identified cause in 22%; the origin was undetermined in 41%. There were multiple abscesse s in 11%. The abscess was <2 cm in diameter in 21%. In two-thirds of t he patients, the intracranial pressure was raised, there were localizi ng neurologic signs in 33%, and in 28% there were epileptic seizures. The computed tomographic (CT) feature of an abscess in the capsular st age was a thin, regular, and uniform, ring-like enhancement. In the ce rebritis stage, nine out of 17 patients showed a uniform enhancement t hroughout the lesion. Since 1989, 14 cases have been investigated with magnetic resonance imaging (MRI). In 11, the abscess was in the capsu lar stage. In both T1- and T2-weighted images, the abscess and the sur rounding inflammatory area were well demonstrated, and with T2-weighti ng, the capsule showed a low-intensity signal clearly. In the three ab scesses in the cerebritis stage, there was a uniform abnormality with indistinct margins between the abscess, inflammatory edema, and surrou nding grey and white matter. All cases received a combination of wide- spectrum antibiotics before the organism was identified; and later the medication was administered according to bacteriologic indication of the organism of 112 cases, organisms were identified in 71%, with anae robic organisms occurring in 30% of these. In 127 cases, surgical trea tment was used: either repeated aspiration, excision or both. We treat ed 13 cases that had small, early, or multiple abscesses with antibiot ics only. The mortality with surgical treatment was 7.9%, and no case treated conservatively died.