CT studies before and after CNS treatment for acute lymphoblastic leukemia and malignant non-hodgkin's lymphoma in childhood.

CT was performed on 72 children with acute lymphoblastic leukemia or non-Hodgkin's lymphoma. Thirty-two of these patients were investigated prior to CNS radiation and intrathecal methotrexate therapy. Ten of these patients (31%) were known to have hydrocephalic dilatation of the CSF spaces. Clinical data and subsequent observations with analysis of the CT findings show that no difference in the attenuation values of brain tissue occurs in the absence of a CNS relapse. The percentage of abnormal findings before and after therapy remains constant. The adverse late effect described in the CT literature seem principally to be damage diagnosed too late. It is questionable if the CT demonstration of dilated CSF spaces before treatment has a prognostic significance.