Reactive gliosis simulating butterfly glioma: a neuroradiological case study.

Reactive gliosis was found in a 40-year-old man who presented with intractable seizures thought to be due to a malignant neoplasm. Although two separate lesions located bilaterally in the frontal lobes were evident on the computed tomographic scan, a connection between these lesions along the fibers of the corpus callosum was clearly demonstrated on T2-weighted magnetic resonance images. The unusual radiological appearance of this gliosis, which simulated a malignant butterfly glioma on magnetic resonance imaging (MRI), is reported. Because MRI is still a new modality, its images should be interpreted with judicious caution.