Figure 3.

Ultrasound signal processing correspondence with CT scanning position and signals of the respiratory belt. (A) CT scanning position (blue and red lines) and the corresponding respiration wave numbers in 4DCT: coronal plane, (B) signals of the respiratory belt, (C) respiratory motion signals of the diaphragm phantom captured by ultrasound imaging at the same time as performing CT scans, and (D) average diaphragmatic motion signals. CT, computed tomography; 4DCT, four-dimensional computed tomography.