Structure visibility and online adaptation suitability of a new high-performance ring-gantry cone-beam computed tomography imaging system in thoracic radiotherapy

Background and purpose: in thoracic radiotherapy by quantifying structure visibility and online adaptive radiotherapy (oART) suitability. Materials and methods: acquired on consecutive days, were included. Four observers independently scored all 240 CBCT datasets on structure visibility and oART suitability (1-5 scale). The effect of respiratory motion management on image quality enhancement was determined by comparing cohort-specific score differences. Results: -based scores increased significantly (p < 0.05) in both cohorts for structure visibility (lung: 2.8 to 3.1; breast: 3.1 to 3.8) and oART suitability (lung: 2.6 to 2.9; breast: 3.1 to 3.9). Structure visibility (oART suitability) score differences increased with deep-inspiration breath-hold (p < 0.001) compared with free-breathing, by on average 0.38 (0.39). Conclusion: .