Nuclear Medicine/CNS

Central Nervous System PET/CT For Tumor INDICATION For the evaluation or diagnosis of tumors of the central nervous system PROCEDURE Alternate techniques exist. We describe the more common methods. Dimension In 2D mode, septa are usually used to collimate using coincidental detection between 2 adjacent detector rings. In 3D mode, all the detector rings are used, which does not necessitate septum separation. Static Imaging The traditional method of acquisition Dynamic imaging A newer, and less used method for detection. Using this approach, there is the potential to measure the metabolic kinetics of a region of interest over time. A time-activity curve can be generated using definable ROIs, which has been used to pre-stage tumors with imaging alone. Limitations of this technique includes the (1) highly difficult and technical nature of the technique; (2) somewhat longer time in which the patient needs to keep their head motionless; (3) reliance on arterial input function for metabolic analysis which can be an invasive procedure; (4) lack of compensation for the increased expertise and time needed to acquire and interpret scans; (5) limited outcomes-based research to validate the technique for standard practice. PROCESSING INTERPRETATION For Cognitive INDICATION For the evaluation or diagnosis of tumors of the central nervous system PROCEDURE Static imaging Stuff PROCESSING INTERPRETATION Waxman -- "Society of Nuclear Medicine Procedure Guideline for PDG PET Brain Imaging" (Waxman A.D. Online PDF. Ver 1.0. Feb 9, 2009. Acronyms used ROI - Region of Interest