Liquid xenon can be used as a scintillator for time-of-flight positron emission tomography (TOF-PFT) owing to its fast responses and high scintillation yield. For confirmation, a prototype model was constructed and tested. The results were better than those obtained with commercially available crystal PET scanners, except energy resolution Was Slightly worse than with a GSO crystal PET. Using the results and simulations, a full-size liquid xenon scintillation TOF-PET scanner was designed and its possible realization discussed. (c) 2006 Elsevier B.V. All rights reserved.