An In-Bore Audio-Visual Respiratory Coaching Projector for Ring Gantry Systems.

We have proposed an in-bore audio-visual respiratory coaching projector for use with ring gantry linacs and four-dimensional computed tomography (4D CT) systems. A respiratory coaching application was installed on a commercially available mobile projector that includes a computer. The projector was placed on a patient couch, with the projected movie displayed on the inner wall of the bore. The workflow was tested using a ring gantry linac as well as a 4D CT unit, and the results demonstrated the feasibility and practicality of the proposed approach.