ESTRO 2024 - Abstract Book

S17 ESTRO 2024 Novel breathing control strategies for radiation delivery are being explored. These include non-invasive mechanical Invited Speaker

ventilation to take over the breathing of conscious and unsedated patients. This has shown to be safe in patients with

breast cancer 7,8 .

Regularized breathing with non-invasive mechanical ventilation at frequencies of 20 to 25 breaths per minute (brpm)

resulted in significantly smaller diaphragm motion amplitudes compared to free breathing 9,10 . Recently, we found an

even greater reduction of the right hemidiaphragm motion using non-invasive mechanical ventilation at 60 brpm

combined with positive end expiratory pressure 11,12 . Preliminary results of motion analysis of the left hemidiaphragm

on MRI showed a decrease of almost 50% compared to free breathing. Moreover, the combination with positive end

expiratory pressure demonstrated beneficial changes in organ shape and position resulting in larger lung volumes,

an elongated heart shape, and a greater distance between the heart and the stomach wall (see figure below).

Volunteers considered this form of breathing regularization comfortable.

Non-invasive mechanical ventilation induced regularized breathing at a frequency of 60 brpm with positive end

expiratory pressure has the potential to elevate the accuracy and efficacy of cardiac radioablation to a higher level.

We are therefore exploring the feasibility of this breathing control strategy in cardiac radioablation.

References

1. Zeppenfield et al., 2022; doi: 10.1093/eurheartj/ehac262. 2. Balgobind et al., 2023; doi: 10.1016/j.radonc.2023.109949. 3. van der Ree et al., doi: 10.1016/j.hrthm.2020.03.013. 4. Stevens et al., 2023; doi: 10.1016/j.radonc.2023.109844. 5. Lydiard et al., 2021; doi: 10.1002/mp.14661. 6. Shah et al., 2023; doi: 10.1007/s10554-022-02734-5. 7. Parkes et al., 2016; doi: 10.1259/bjr.20160194 8. vander Veken et al., 2023; doi: 10.1016/j.radonc.2023.109598. 9. West et al., 2019; doi: 10.1016/j.ijrobp.2018.11.040. 10. van Kesteren et al., 2022; doi: 10.1186/s13014-022-02068-5.