Computed Tomography of Japanese Encephalitis with Clinical Correlation

ABSTRACT

The computed tomographic (CT) and clinical findings in 9 patients with serologically confirmed Japanese encephalitis were reviewed. In 6 patients with prominent pyramidal and extrapyramidal symptoms and signs, the main CT finding was low density areas in the thalamus, internal capsule, basal ganglia, and midbrain. Low density areas were compatible with the anatomical distribution of pathologic lesions in Japanese encephalitis. Diffuse low density in the periventricular white matter was evident in 5 of 6 cases, with ventricular compression in 2 cases, between the 1st and 7th day of illness. There was enlargement of the third and lateral ventricles and cortical sulci dilatation in 3 cases on or after the 21st day of illness. In once CT scan obtained on the 10th day of illness, diffuse low density in the periventricular white matter was observed with enlargement of lateral ventricles and cortical sulci dilatation. Gyral enhancement was noted in 3 of 4 cases within 4 days after the onset of symptoms. There was a limited correlation between the clinical and CT findings.