Contribution of 3D Modeling in Surgical Management of Pediatric Retroperitoneal and Pelvic Tumors

The investigator will inform the child and his parents during the pre-surgical consultation, and will collect their non-opposition to be included in the study at the latest on the day of the MRI examination or CT scan. Patients requiring emergency imaging will not be included. Pelvic tumors will benefit from MRI imaging and renal tumors from MRI and/or CT scan. A CT scan will be carried out for retroperitoneal tumors other than renal tumors (mainly neuroblastomas). All of the above examinations are carried out as part of the usual treatment, in the month preceding the surgery. Pre-operatively After the imaging has been carried out, the 2D images will be presented to the patient and his family before surgery as it is done routinely. The 3D image will be showed afterwards. The family will have the opportunity to ask questions which the surgeon will answer as usually done. The specific questionnaire will be completed by the patient and his family at the end of the consultation and given to the research team. Once the patient is included and the examinations have been carried out, the operating surgeons and their assistants (help No. 1 and 2) will look at the 2D images, followed by the 3D images secondly a few days before surgery. They will complete the specific questionnaire and give it to the research team. Once the patient is included and the imaging examinations have been carried out, surgeons external to the service will be contacted by the research team to organize a remote review session. The 2D images will be presented to them first, followed by the 3D images on the visualization software, via a remote communication system with screen sharing. They will complete the specific questionnaire independently and a copy of the questionnaires will then be sent to the research team by email and the originals sent by post. Intraoperatively: The 3D model of the patient will be displayed in the operating room, and/or integrated into the robot's display console (for robot-assisted surgeries) during the surgical procedure. At the end of the surgery, the operating surgeon and his assistants will complete (independently) a questionnaire on the consistency of the 2D and 3D images with the anatomy identified during the procedure and on the help or not provided by the 3D model.