biostudies-literatureUnknown28Ehrbar SRadiotherapy in expiration breath-hold (EBH) has the potential to reduce treatment volumes of abdominal targets compared to an internal target volume concept in free-breathing. The reproducibility of EBH and required safety margins were investigated to quantify this volumetric benefit. Pre- and post-treatment diaphragm position difference and the positioning variability were determined on computed tomography. Systematic and random errors for EBH position reproducibility and positioning variability were calculated, resulting in margins of 7 to 12 mm depending on the prescription isodose and fractionation. A reduced volume was shown for EBH for lesions with superior-inferior breathing motion above 4 to 8 mm.Physics and imaging in radiation oncology100509https://www.ebi.ac.uk/biostudies/studies/S-EPMC10692905biostudies-literatureIntra- and inter-fraction breath-hold variations and margins for radiotherapy of abdominal targets.PMC10692905Perryck SMoreira AAndratschke NEhrbar SPavic MSchrader MGarcia Schuler HMarvaso GGuckenberger MVan Timmeren JETanadini-Lang SfalseIntra- and inter-fraction breath-hold variations and margins for radiotherapy of abdominal targets.Radiotherapy in expiration breath-hold (EBH) has the potential to reduce treatment volumes of abdominal targets compared to an internal target volume concept in free-breathing. The reproducibility of EBH and required safety margins were investigated to quantify this volumetric benefit. Pre- and post-treatment diaphragm position difference and the positioning variability were determined on computed tomography. Systematic and random errors for EBH position reproducibility and positioning variability were calculated, resulting in margins of 7 to 12 mm depending on the prescription isodose and fractionation. A reduced volume was shown for EBH for lesions with superior-inferior breathing motion above 4 to 8 mm.2023-01-01T00:00:00Z2023 Oct2025-04-05T11:45:45.427Z2025-04-05T11:45:45.427ZS-EPMC106929053804564010.1016/j.phro.2023.100509