Application of 4DCT-Based Pulmonary Ventilation Imaging in Lung Cancer Radiotherapy

This retrospective single-center study investigates whether four-dimensional CT (4DCT)-based lung ventilation imaging can guide functional lung avoidance radiotherapy (FLAR) for patients with primary lung cancer. Ventilation maps generated from planning 4DCT are used to identify well-ventilated lung regions, enabling paired comparison between functional lung avoidance radiotherapy plans and conventional anatomic radiotherapy plans. The study aims to assess whether incorporating functional lung information into radiotherapy planning can reduce radiation exposure to well-ventilated lung while maintaining adequate tumor coverage, and to explore its relationship with radiation-induced lung injury. All analyses are based on existing clinical imaging, treatment planning data, and follow-up records. No additional interventions, imaging, or procedures are performed as part of this study.