Computed tomography of the brain following prophylactic treatment with irradiation therapy and intraspinal methotrexate in children with acute lymphoblastic leukemia.

In 28 children with acute lymphoblastic leukemia (ALL) computed tomography (CT) was performed in order to demonstrate possible cerebral changes following treatment with prophylactic irradiation and intraspinal methotrexate (MTX). The time of CT-scan examination varied from 1 year and 1 month to 10 years and 1 month after diagnosis of ALL. The age of the children ranged from 3 years and 11 months to 14 years and 5 months. Six children had normal CT scans, 12 children had slight atrophy-like changes, and nine had severe cerebral atrophy. Two patients in the latter group presented an enlarged ventricular system as well. In one patient intracerebral calcification was the only pathologic finding. The severe changes were seen in children of all age groups, but predominantly in children with a short duration of their disease, severe symptoms, and frequent marrow relapse. Changes induced by steroid therapy may be reversible. No satisfactory explanation of the demonstrated cerebral pathologic findings can be given, except that they are the consequences of the combination of total therapy and severity of disease in the individual patient. Measurement of attenuation coefficients in grey and white matter shows increasing values with age during childhood. A combination of decreasing attenuation coefficients, especially in the white matter, and the finding of severe atrophy seems to be a bad prognostic sign.