Imaging of brain tumors after therapy.

Imaging is used routinely for the diagnosis and follow-up of patients with brain tumors. Although the latest MR imaging techniques are able to provide an excellent depiction of abnormalities in soft tissue morphology, they are frequently unable to distinguish edema and treatment-induced necrosis from recurrent or residual tumor. For assessment of response to therapy, it is therefore important to use functional imaging modalities such as PET and MR spectroscopy.