The diagnosis of the intracerebral malignant lymphomas by diffusion-weighted MR Imaging

The purpose of this study was to evaluate the clinical usefulness of diffusion-weighted magnetic resonance (MR) imaging (DWI) in the examination of intracerebral Malignant Lymphomas. This study included 15 patients with a malignant lymphoma. The findings0on DWI0in malignant lymphomas were compared with those in020 glioblastomas and in030 brain metastases during recent 4 years. DWI was acquired by using the diffusion-weighted, single-shot, multislice, echo planar SE sequence. In all patients with malignant lymphomas, areas of tumor that were significantly enhanced on T1-weighted MR images after contrast material were markedly hyperintense on DWI. Tumor sites of both glioblastomas and brain metastases were also hyperintense on DWI. However, the findings of apparent diffusion coefficients (ADC) in malignant lymphomas were lower than those in glioblastomas and those in brain metastases. This results were greatly helpful in order to descriminate from malignant lymphomas to glioblastomas and brain metastases preoperatively. DWI, especially ADC images, are clinically a useful technique for examining malignant lymphomas. It may enable us to differentiate various components of the tumor (e.g., enhancing, nonenhancing, cystic, necrotic, or recurrence). DWI is a new powerful tool in the characterization of malignant brain tumors.