The Potential Roles of¹⁸F-FDG-PET in Management of Acute Stroke Patients

Extensive efforts have recently been devoted to developing noninvasive imaging tools capable of delineating brain tissue viability (penumbra) during acute ischemic stroke. These efforts could have profound clinical implications for identifying patients who may benefit from tPA beyond the currently approved therapeutic time window and/or patients undergoing neuroendovascular treatments. To date, the DWI/PWI MRI and perfusion CT have received the most attention for identifying ischemic penumbra. However, their routine use in clinical settings remains limited. Preclinical and clinical PET studies with [ 18 F]-fluoro-2-deoxy-D-glucose ( 18 F-FDG) have consistently revealed a decreased 18 F-FDG uptake in regions of presumed ischemic core. More importantly, an elevated 18 F-FDG uptake in the peri-ischemic regions has been reported, potentially reflecting viable tissues. To this end, this paper provides a comprehensive review of the literature on the utilization of 14 C-2-DG and 18 F-FDG-PET in experimental as well as human stroke studies. Possible cellular mechanisms and physiological underpinnings attributed to the reported temporal and spatial uptake patterns of 18 F-FDG are addressed. Given the wide availability of 18 F-FDG in routine clinical settings, 18 F-FDG PET may serve as an alternative, non-invasive tool to MRI and CT for the management of acute stroke patients.