Evaluation of brain and epidural abscesses by computed tomography.

Most brain abscesses have a characteristic but nonspecific appearance on computed tomography (CT), consisting of a ring configuration of the abscess capsule which shows marked enhancement after injection of contrast material. CT scanning is invaluable in both the initial investigation of a brain abscess and assessment of its response to therapy. The CT scan showed a peripheral low-density crescent in one case of epidural abscess.