Computed tomography of intracranial lymphoma.

The appearances on computed tomography (CT) of 17 patients with histologically proven intracranial lymphoma have been analysed and abnormalities detected in 16. Four of the patients had systemic lymphoma. Multiple lesions were seen in eight patients (47%), in six of whom the multiple lesions in each patient were of similar appearance. There was good macroscopic correlation between the CT and post-mortem appearances in the eight patients who subsequently died, although in five, histological examination showed more extensive infiltration. Meningeal involvement was seen more commonly in the cases of systemic lymphoma than in the purely cerebral lymphomas, but parenchymal lesions were equally common in both. Grey matter lesions tended to be clearly demarcated, of increased density with little oedema or displacement; homogeneous density enhancement was produced by the intravenous injection of contrast medium. White matter lesions were usually poorly demarcated, of variable density with marked oedema and displacement, and with heterogeneous enhancement.