ESTRO 2020 Abstract book

S1075 ESTRO 2020

dyspnea 1(1), 1(1) and 2(1), respectively (p=0.923). During all sessions, SpO2 did not changed. Conclusion No difference in subjects’ well-being was observed during BHPV sessions between the use of music or VR as distraction techniques. Given these results, the implementation of such distraction devices during BHPV may have only little interest and being time-consuming for the medical staff. However, it seems important to note that the level of stress experienced by healthy volunteers may not reflect the level of stress of patients treated for cancer. Therefore, further analyses should be performed on patient in order to counterweight our current results, given the financial cost their implementation may require. PO‐1834 Initial evaluation of a new immobilization system for lung SBRT F.J. Conejo Monasterio 1 , A. Montejo Arteche 1 , M. Fernandez Montes 1 , N. Sánchez Hernández 1 , N. Pereda Barroeta 1 , J.A. Válgoma Solanas 1 , M. Castanedo Álvarez 1 1 hospital Universitario Basurto, Radiotherapy, Bilbao, Spain Purpose or Objective The treatments in which high doses are administered in a few sessions (SBRT and SRS) require great precision. The movement due to breathing causes an inconvenience when reproducing that required precision. Different techniques such as gating, tracking or dampening are often used to reduce the effect of respiratory movement. In our service we have chosen to use the latter for SBRT treatments. We have a system designed to reduce the movement of both the lesions and the adjacent organs in thoracic- abdominal regions. In this work we intend to evaluate the accuracy of our immobilization system in the initial positioning of the patient and during the treatment by the use of CBCT images before, during and after the treatment. Material and Methods From our database, a total of 40 sessions have been analyzed, corresponding to 12 patients treated with lung SBRT. In order to increase the precision and minimize movement, at the time of performing the simulation CT and in each treatment session, the eXacradle compressor (AnatGe) has been used. It consists of three differentiated modules: support, abdominal compression and diaphragmatic compression. It is compressed in a region close to the tumour in order to reduce respiratory movement as much as possible, trying the arc compressor not to interfere with the treatment fields.In each treatment session, the patient is compressed in the same way as in the CT simulation. A minimum of four CBCTs are performed: two before treatment, one intra-fraction and the last at the end of treatment. We compare the CBCTs with our simulation CT allowing displacements (made by our robotic table) at the most 3 mm for translation movements and 3 degrees for rotational movements.

PO‐1833 What is the best modality to distract patients during prolonged breath‐holds? N. Audag 1,2,3 , G. Van Ooteghem 4,5 , M. Pirenne 6 , G. Liistro 1 , G. Reychler 1,2,3 , X. Geets 4,5 1 Cliniques universitaires Saint Luc, Service de Pneumologie, Brussels, Belgium ; 2 Cliniques universitaires Saint Luc, Unité de kinésithérapie, Brussels, Belgium ; 3 Université catholique de Louvain, Pôle de Pneumologie- ORL & Dermatologie PNEU- Institut de Recherche Expérimentale et Clinique- Groupe de Recherche en Kinésithérapie, Brussels, Belgium ; 4 Cliniques universitaires Saint Luc, Department of Radiation Oncology, Brussels, Belgium ; 5 Université catholique de Louvain, Molecular Imaging- Radiotherapy and Oncology MIRO- Institut de Recherche Expérimentale et Clinique, Brussels, Belgium ; 6 Université catholique de Louvain, Faculté des sciences de la motricité, Louvain la neuve, Belgium Purpose or Objective Long lasting breath-holds (> 10 min) can be obtained using intrapulmonary percussive ventilation (IPV), reducing or nearly suppressing the thoracic movements. These prolonged breath-holds, combined to IPV (BHPV), could therefore be used for radiotherapy purposes. The aim of this study was to evaluate if, during BHPV sessions, the adjunction of music or virtual reality (VR) could increase the subjects’ well-being. Material and Methods We recruited healthy volunteers. They first followed a training of 2 sessions of 5 minutes to adjust IPV settings and let them get familiar with BHPV. This latter was performed with a non-invasive IPV device (Pegaso A-Cough Perc®, Dima Italia, Italy) with a buccal mask at ambient air. Then, they realized 3 repeated sessions of 10 minutes of BHPV : one control session, and two other sessions with different sources of distraction (music and VR with 3D movie), all randomly assigned to each volunteer, and done with at least one day in between. At the end of each session, subjects’ comfort (1= horrible; 10= perfect), relaxation (1= horrible; 10= perfect) and dyspnea (1= no dyspnea; 10= major dyspnea) were assessed with a Likert scale. Pulsed oxygen saturation (SpO2) was monitored before and after each session using a finger oximeter (Onyx, Nonin, USA).

Results Twelve subjects (7F, 24 ± 3y) were recruited. The results concerning comfort showed no significant difference in the Likert rating scores between music, VR and control sessions with a median score of 8(2), 7(4) and 8(2), respectively (p=0.663). For the relaxation level, the scores were 8(1), 9(3) and 7(4), respectively (p=0.300), and for

Results