Magnetic resonance imaging of abdominal masses in the pediatric patient.

Magnetic resonance (MR) plays a unique role in the diagnosis and management of pediatric abdominal masses. The "as low as reasonably achievable" (ALARA) radiation dose of CT is zero when substituted by MR. Whole body MR may also compete with PET imaging to stage abdominal tumors. Specific advantages of MR include determination of resectability of hepatic tumors using MRI and MRA; staging of neuroblastoma in the bone marrow, lymph nodes, liver, and spinal canal; response of bilateral Wilms tumor and nephroblastomatosis; detection of pelvic tumors with sagittal sectioning, and peritoneal tumors with contrast enhancement.