Computed tomography appearance of Herpes Simplex encephalitis.

The eight computed tomography (CT) scans in five patients with proven herpes simplex encephalitis (HSVE) showed a low density lesion in the deep temporal lobe. In one patient the deep frontal and occipital lobes were also involved. Contrast enhancement was present in all patients examined within 78 days of the onset of symptoms. CT is valuable in the investigation of patients suspected of having HSVE and for whom it is vital to exclude a temporal lobe tumour or abscess. A CT examination may indicate the site for a brain biopsy to confirm the diagnosis.