The application of stereotactic radiosurgery to disorders of the brain.

Stereotactic radiosurgery is the first widely used "biological surgery." The opportunity for surgeons working with radiation oncologists and medical physicists to affect cell structures with both direct and indirect vascular effects has transformed neurosurgery. As a minimal access surgical approach, it fits well into the patient goals of functional preservation, risk reduction, and cost-effectiveness. Longer-term results have been published for many indications. For many disorders, it may be better to "leave the tumor in rather than take it out." Radiosurgery has had an impact on the management of patients with vascular malformations, all forms of cerebral neoplasia, and selected functional disorders such as trigeminal neuralgia and tremor. It can be performed alone when lesion volume is not excessive or as part of a multimodality strategy with resection or endovascular surgery. Epilepsy, behavioral disorders, and other novel indications are the topics of current investigation. The combination of high-resolution imaging, high-speed computer workstations, robotics, patient fixation techniques, and radiobiological research has put radiosurgery into the practice of almost all neurosurgeons.