Abstract
The authors investigated the temporal response to the enhancement by the contrast medium infusion in the computed tomography for the differential diagnosis of intracranial tumors. In ten cases of intracranial tumors (two cases of meningiomas, acoustic neurinomas, glioblastomas and metastatic cancers and one case of pituitary chromophobe adenoma and craniopharyngioma), the effect of the enhancement was examined at 15, 30, 60, 120 and 180 minutes after the infusion of the contrast medium. The results were analysed about both the enhanced figures of the lesion on the monitor TV and the estimation of the attenuation value of the lesions.
The results about the enhanced figures were as follows; 1) each part of the lesion did not always show the synchronous appearance or withdrawal, 2) there were time differences in the appearance or withdrawal of the enhanced effect according to the kinds of the intracranial tumors and 3) the precise size or form of the lesions could not be sufficiently demonstrated in the early scan within 30 minutes and the delayed scan was mandatory for the precise diagnosis.
According to the analysis of the attenuation response by the print-out data, glioblastomas and metastatic cancers with marked destruction of the blood-brain barrier showed late but prolonged response to the enhancement and meningiomas with rich vascular beds showed early appearance and rapid withdrawal of the response. The other tumors showed the intermediate pattern of the response.
In conclusion, the analysis of the delayed scan in computed tomography will add more precise information about the differential diagnosis of the intracranial tumors.
