Dosimetric impact of 4-dimensional computed tomography ventilation imaging-based functional treatment planning for stereotactic body radiation therapy with 3-dimensional conformal radiation therapy

We compared anatomical and functional plans for SBRT with 3-dimensional conformal radiation therapy for the first time. Our results demonstrated that a functional plan for SBRT reduced the dose in the high-functional regions without a significant change in the total lung or planning target volume even if the radiation technique cannot modulate beam intensity. Thus, this technique can be safely used in functional planning for SBRT.