CT and MR imaging in Hodgkin's disease--present and future.

Initial staging of Hodgkin's disease is crucial to determine the location and extent of disease, and is the hallmark for the choice of treatment. At present, the established radiological technique for staging Hodgkin's disease is computed tomography (CT). Modern multidetector row CT scanners allow fast imaging from the scull base to the groins during a single breath hold with a spatial resolution of approximately 1 mm. Both, nodal and extranodal involvement of Hodgkin's disease can be diagnosed with CT. Magnetic resonance (MR) imaging is another useful cross-sectional imaging modality for staging Hodgkin's disease. The development of fast MR imaging techniques has considerably reduced imaging time without compromising the quality of MR images. As a consequence, MR imaging is now considered to be as diagnostic as CT for staging Hodgkin's disease. The excellent soft-tissue contrast and the lack of exposure to ionizing radiation are the main advantages of MR imaging. For the detection of extranodal Hodgkin's disease, MR imaging is superior to assess involvement of the brain, the spinal cord and bone marrow; while CT allows excellent evaluation of lung disease. Common major problems in staging Hodgkin's disease are still the detection of nodal involvement in normal sized lymph nodes and residual tumor masses after therapy. In the future, newly developed lymphotropic contrast agents for MR imaging might be helpful to answer these questions.