Fig. 2From: ITV versus mid-ventilation for treatment planning in lung SBRT: a comparison of target coverage and PTV adequacy by using in-treatment 4D cone beam CTa Relative PTVs normalized to PTVITV + 5mm for the different PTV margins. Relative PTVs are plotted in (b) as a function of target motion amplitude vector. PTV, as a function of respiratory amplitude, clearly shows a strong correlation with the MidV-based strategyBack to article page