Evaluation of threshold and gradient based 18F-fluoro-deoxy-2-glucose hybrid positron emission tomographic image segmentation methods for liver tumor delineation

Three PET segmentation methods were identified above as potential tools to accelerate liver lesion delineation. The edge method appears to be the most practical for clinical implementation as it does not require calculation of SUV statistics. However, the performance of all segmentation methods showed large lesion-to-lesion fluctuations. Therefore, such methods may be suitable for generating initial estimates of FDG-PET avid volumes rather than being surrogates for manual volume delineation.