Abstract: The CT findings in 100 cases of brain metastases were analysed,and they were classified into four types:nodular,ring-shaped,irregular and mixed basing on contrast enhancement CT scaning. The CT features are as follows:1.Hypodensity in most cases,hyperdensity and equal-density in a small number of cases;2.More nodular and mixed types than others types no obvious;differance in CT findings between brain metastases and various types of lung carcinoma and other primary carcinomas;3.There was relatively extensive edema not in proportion to the size of the lesions;4.The rather large single metastasis was usually not easily differentiated from glioma; 5.Most lesions located near cerebral cortex but lesions from breast carcinoma usually in cerebellar hemisphere.
The contrast enhancement CT scan may,therefore,be considered to be very important for the judgement of brain metastasis.Differential diagnosis of brain metastasis is finally disscussed.