Imaging of brain tumors after administration of L-(N-13)glutamate: concise communication.

Cyclotron-produced L-(N-13)glutamate was used to visualize malignant intracranial tumors in 12 pediatric patients who had evidence of recurrent disease as documented by computed transaxial tomography (TCT). Imaging was performed using a rectilinear scanner, gamma camera, or a positron-emission tomograph (PET). The results indicate that N-13 is rapidly taken up by a majority of brain tumors following the administration of L-(N-13)glutamate, and that N-13 uptake is correlated with breakdown of the blood-brain barrier as demonstrated by contrast TCT or pertechnetate (Tc-99m) studies. The feasibility of using this agent in conjunction with PET is established.