Real-time monitoring and control on deep inspiration breath-hold for lung cancer radiotherapy--combination of ABC and external marker tracking.

Purpose: In this article, the breath-hold and gating concepts were combined for application of lung cancer radiation treatment. The tumor movement was immobilized based on deep inspiration breath hold (DIBH), in which the breath-hold consistency and stability were monitored by infrared (IR) tracking and controlled by gating with a predefined threshold. The authors' goal is to derive the benefits from both techniques, namely, the minimized treatment margin and the known advantages of deep inspiration.