Magnetic resonance imaging diagnosis of primary lymphoma in the brain

Objective To study retrospectively the MRI features and pathological findings of primary lymphomas in the brain for increasing diagnosis accuracy.Methods MRI and pathological findings of 17 cases of primary lymphoma in the brain were comparatively studied retrospectively.Results Seventeen patients presented a single lesion in 7 cases (41%) and multiple lesions in 10 cases (59%).The common sites were white matter of the frontal and parietal lobe,corpus collusum and the basal ganglia.The lesions showed hypointensity or mildly hypointensity on T1WI in 17 cases and iso-intensity or slightly hyperintensity on T2WI in 14 cases (82%).Necrosis and hemorrhage were rarely seen.Most lesions showed mild to moderate peritumoral edema and mass effect.On enhanced T1WI,majority displayed markedly homogeneous enhancement,sometimes lesions spread along CSF.Conclusion MRI findings of primary lymphomas in the brain have some characteristics.It is possible to make preoperative diagnosis in most cases of primary lymphomas,however differentiate diagnosis should be considered in atypical cases.