Impact of a Hypnotic Recording on Artifacts in 4D CT in the Context of Stereotactic Body Radiation Therapy for Lung Cancer

This is a single-center prospective cohort study evaluating the impact of a simple audio recording hypnosis system on the occurrence of artifacts on 4D CT scans in patients requiring SBRT radiotherapy for lung lesions (peripheral or central).

The primary objective of the study is to evaluate the use of a hypnotic recording on the reduction of artifacts in 4D CT scans for patients undergoing stereotactic body radiation therapy for lung cancer.

The secondary objectives are to evaluate:

* the impact of hypnotic recording on the reduction of artifacts on intrathoracic structures (trachea, main bronchi, diaphragm, lesions, heart, and lungs), * the regularity of respiratory amplitude, * the regularity of respiratory rate, * the volume of Internal Target Volume (ITV), * the reproducibility of ITV volume, * patient satisfaction.

1. Before this dosimetric scan, the patient will complete a self-administered questionnaire on anxiety: the HADS-A questionnaire (Hospital Anxiety and Depression Scale-only questions relating to anxiety).

During this examination, the MERM explains the dosimetric scan procedure to the patient. After the immobilization system has been set up in accordance with the department's standard protocol, a 4D CT scan will be performed while asking the patient to breathe regularly. In the event of an artifact at the level of the lesion, a second 4D CT scan will be performed under the same conditions. 2. The hypnotic audio recording will be played through the room's speakers. The hypnotic recording is structured in three stages, with a 5-minute induction phase, a 5-minute working phase, and finally a 5-minute return phase.

After 5 minutes of playback, the 4D CT scan for the study is performed using the same acquisition parameters as the free 4D CT scan. 3. Following the first radiotherapy session and for all patients included in the study, a 4D dosimetric scan will be performed using the hypnotic recording again, as described above, in order to assess the inter-fraction reproducibility of the ITV volume.

Following this second 4D CT scan under hypnosis, patient satisfaction will be assessed (using a Likert scale questionnaire).