Breathing can cause motion of tumors that are located in or near the lungs. This tumor motion requires special technology to image and target them for treatment. Our center’s CT is capable of 4D imaging, meaning that tumors can be visualized at each point in the breathing cycle. The 4D image allows the physician to precisely pinpoint the tumor for treatment. If the tumor’s motion is large the physician may choose to implement radiation therapy that corrects for the motion. These therapies included deep inspiration breath hold, shallow breathing techniques, or respiratory gating. Our linear accelerator is equipped with respiratory gating, which applies radiation treatment to the tumor at certain parts of the breathing cycle. The machine tracks the breathing cycle and turns the radiation on and off as planned by the Radiation Therapy Treatment Team. The use of respiratory gating can reduce radiation dose to healthy organs and tissues.