ESTRO 2024 - Abstract Book

S5607

RTT - Patient care, preparation, immobilisation and IGRT verification protocols

ESTRO 2024

Keywords: Open-face masks, stability, accuracy

2747

Digital Poster

Visual coach to improve treatment of deep inspiration breath hold for left breast patients

Aurora Zucca 1 , Nicola Lambri 1,2 , Carmela Galdieri 1 , Damiano Dei 1,2 , Davide Franceschini 1 , Ruggero Spoto 1 , Mariya Ilieva 1,2 , Anna Bertolini 1,2 , Luca Dominici 1 , Ciro Franzese 1,2 , Pietro Mancosu 1 , Marta Scorsetti 1,2 1 IRCCS Humanitas Research Hospital, Radiotherapy and Radiosurgery Department, Milan, Italy. 2 Humanitas University, Department of Biomedical Sciences, Milan, Italy

Purpose/Objective:

Deep inspiration breath hold (DIBH) is a technique used to deliver RT only while the patient holds their breath at the maximum inspiration. DIBH for RT of the left breast has been demonstrated to reduce the mean dose to the heart, and many centres currently use it [1,2]. However, there is still limited evidence on intra-breath hold stability. In this study, we systematically evaluated the stability of breathing during DIBH and the impact of introducing a visual coach for the patient during delivery.

Material/Methods:

Since 2018, 1499 left breast patients were treated at our center in 15 fractions of 3.2-2.7 Gy/fr using volumetric modulated arc therapy (VMAT). The breathing cycle was monitored using a real-time position management (RPM) respiratory gating (Varian). Patients were instructed to breath hold via a human voice. A visual coach was introduced in January 2020 to give the patients a real-time feedback of their breathing during delivery. In this study, 57 DIBH breast patients treated with two arcs were retrospectively selected, of which 32 underwent RT with the aid of visual coach. A total of 855 data records were extracted by an RTT to quantify the impact of the visual coach utilization. Specifically, the RPM breath traces were analysed to measure the DIBH threshold and to categorize the intra-breath hold stability of each session as “stable” or “unstable”. Furthermore, for each arc, the delivery time and number of interruptions (i.e., number of breaths) were considered. The extracted data were evaluated before and after the introduction of the visual coach. The Mann-Whitney and t-test were used for statistical comparisons (p<0.05 significant).

Results:

The percentage of patients treated with DIBH increased from 25% in 2018 – before the introduction of the visual coach - to 43% in 2022/23 - after its consolidated implementation in clinical practice. Thanks to the introduction of the visual coach, the percentage of “stable” intra-breath hold sessions increased from 47% to 54% (see Figure 1), and the average (standard deviation) DIBH threshold was reduced from 7 ± 2 mm to 6 ± 1 mm (t-test p<0.05).