[Non-leukemic disease of the central nervous system in children with acute lymphoblastic leukemia. I. Somnolence syndrome (author's transl)].

Prophylactic irradiation of the skull and intrathecal application of methotrexate has proven to be highly effective in preventing central nervous system disease in acute lymphoblastic leukemia or non-Hodgkin-lymphoma. Prophylactic treatment may be complicated by a somnolence syndrome occuring 4--8 weaks after the end of irradiation. The main features of this clinical entity are somnolence, lethargy, dullness, anorexia, headache, and vomiting. EEG frequently displays a distinct slowing of activity. All symptoms are reversible after 3--49 days. The syndrome clearly is consequence of skull irradiation. Its metabolic basis probably is transient disturbance of myelinization.