[Sequential CT findings in low-density non-enhancing gliomas].

Gliomas are sometimes encountered which are not noticeably enhanced in initial computerized tomography (CT) scans. The sequential CT findings of such gliomas, including three malignant astrocytomas, three benign astrocytomas and one malignant oligodendroglioma, were evaluated. The initial symptoms in all subject cases were convulsive seizures. There was no correlation between the mass effect of the low density zone and the grade of histological malignancy. Rather, malignant gliomas disclosed less prominent mass effects, despite the later appearance of an enhanced high density zone. In one case each of malignant astrocytoma and of malignant oligodendroglioma, an enhanced high density zone first appeared 6 to 13 months later. Neither gave evidence of increasing mass effects, either during the follow-up or after appearance of the enhanced high density zone. Questionable low density zones in CT scans should be followed-up for at least 6 months or more in conjunction with other studies.