Functional magnetic resonance imaging - basics and applications in oncology

Functional MR imaging (F-MRI) permits to visualize active processes evolving in the human brain. The shifts in blood oxygenation following local neuronal activation are used for generating an MR signal. Specific procedural problems have to be solved when using F-MRI in patients with brain neoplasms. The relationship between perirolandic tumors and the adjacent motor areas has been studied most intensively. When the resection of tumors in the motor area is considered, functional imaging can help the surgeon to avoid or at least to minimize postoperative functional deficits. Overall, F-MRI study results are useful in at least one crucial preoperative decision step for about 90% of brain tumor patients. Experience with functional imaging in radiotherapy of brain neoplasms is still limited. Presently, F-MRI cannot yet replace intraoperative brain mapping.