History of CNS lymphoma s/p R-CHOP x 6, R-CEOP x 6, 2 cycles Ara-C and methotrexate, now 100 days post auto SCT. There is mild diffuse enhancement along the right trigeminal nerve. Otherwise, there is no evidence of intracranial hemorrhage, mass, or acute infarct. There is new extensive confluent cerebral white matter T2 hyperintensity. There is no abnormal brain parenchymal enhancement. There is a right transfrontal Ommaya catheter that terminates in the right lateral ventricle. The ventricles and basal cisterns are unchanged in size and configuration. There is no midline shift or herniation. There is a small left maxillary sinus retention cyst.
1. Mild diffuse enhancement along the right trigeminal nerve may represent lymphomatous involvement.2. New extensive cerebral white matter abnormality is likely treatment-related, such as methotrexate encephalopathy.