[Characteristics of brain scintigraphy in pediatric age group and its diagnostic value in brain tumors (author's transl)].

The diagnostic value of brain scintigraphy in intracranial diseases has been well recognized. Numerous reports have appeared in the literature concerning its use in adult cases. The reports dealing with pediatrics cases, however, are quite limited in number. The major factors limiting such studies in children may be considered as follows; (1) infratentorial tumors are common in this age group, in which its diagnostic accuracy has been believed to be quite low, (2) problems of exlosing children to radiation and (3) difficulty in keeping children in one position for a considerable length of time. These difficulties were almost overcome by the use of 99m Tc with a very short half life and a gamma camera, resulting in increased application of this procedure to children. The purpose of this report is to analyse and discuss the scintigraphical characteristics in children and evaluate the diagnostic value in brain tumors. The subjects consist of 199 non-tumoral cases and 53 cases of verified brain tumors. Following conclusions were obtained: (1) Aging changes are noted in normal brain scintigrams of children. One of them is related to the mode of visualization of the basal structures in lateral views. The cranial base appears to be flat before the age of 4 years. A triangular process then appears at the cranial base, approaching that of adult over the age of 10 years. Another change is related to appearance of the temporal and occipital muscles over the cranial vault and the posterior fossa. This becomes apparent about the age of 7 years and produces such masking effects as to interfere with diagnosis in this region over the age of 10 years. (2) The choroid plexus are visualized in about 10% of cases. (3) In brain tumor cases, the detecting rate is 93% in gliomas, and 73% in non-gliomatous tumors. It is particularly low in congenital tumors.