Respiratory Motion Correction Strategies in Thoracic PET-CT Imaging

PET-CT scanners allow robust and synergistic fusion of anatomic and functional information, which has improved sensitivity, specificity, and enhancement in the value of PET and CT when assessing tumor response to therapy. Breathing motion and the difference in time resolutions commonly cause motion artifacts and spatial mismatch between the corresponding image sets. Correction for the breathing-induced artifacts represents a particular challenge. This article summarizes the materials, methods, and results involved in multiple investigations of the correction for respiratory motion in PET-CT imaging of the thorax. Some methods use respiratory-phase data selection, whereas others have adopted sophisticated software techniques.