4D PET/CT as a strategy to reduce respiratory motion artifacts in FDG-PET/CT

Abstract

The improved accuracy in tumor identification with FDG-PET has led to its increased utilization in target volume delineation for radiotherapy treatment planning in the treatment of lung cancer. However, PET/CT has constantly been influenced by respiratory motion related image degradation, which is especially prominent for small lung tumors in the peridiaphragmatic regions of the thorax. Here, we describe the current findings on respiratory motion related image degradation in PET/CT, which may bring uncertainties to target volume delineation for image guided radiotherapy for lung cancer. Furthermore, we describe the evidence suggesting 4D PET/CT to be one strategy to minimize the impact of respiratory motion related image degradation on tumor target delineation for thoracic IGRT. This, in our opinion, warrants further investigation in future IGRT-based lung cancer trials. © 2014 Chi and Nguyen.