C W Starr | PubMed Health

PubMed1992

Functional imaging of epileptic foci with PET and SPECT.

Functional imaging with PET and SPECT provides valuable information, helping lateralize and localize the site of an epileptogenic focus. SPECT imaging has been somewhat hampered by lower resolution than PET, and the lack of true "metabolic" radiopharmaceuticals, however SPECT perfusion studies may also help localize the seizure focus. At present, PET metabolic imaging with FDG is the most sensitive functional imaging modality for identifying epileptogenic foci. However with the current availability, lower cost and improved visualization, the diagnostic and prognostic efficacy of SPECT should increase.

Brain↗

PubMed1991

Dynamic stereotactic radiosurgery using a linear accelerator.

We describe a system for stereotactic radiosurgery with a linear accelerator. This technique allows treatment of small (less than 40 mm diameter) intracranial lesions, including vascular malformations, and primary and metastatic tumors that are deep within the brain or in areas not amenable to open surgery. A beam of ionizing radiation (1800 to 2500 cGy) is focused on the center of the lesion, which is determined by stereotactic localization. "Dynamic rotation" of the linac gantry and table continuously about this predetermined point ensures that only the lesion receives the full radiation dose, while the normal structures in the head receive minimal amounts of radiation. The system combines, for the first time in one place, elements of radiosurgical technique developed at various centers. Testing for accuracy compares favorably with results at other centers using linac-based systems as well as comparing favorably with the gamma knife.

Brain Neoplasms↗