Irradiation of moving target using particle therapy system

An irradiation method, comprising:

• providing an irradiation plan to a particle therapy system for irradiating a target volume exhibiting phases of motion caused by a patient's physiological movement, the particle therapy system comprising a beam delivery device operable to scan a pencil beam of particles over the target volume, the irradiation plan comprising:
• a first field for irradiating the target volume in a first phase of motion;
• and
• a second field for irradiating the target volume in a second phase of motion;
• monitoring a tracking device providing values in correspondence with current positions of the target volume and transmitting signals continuously indicating the values to the particle therapy system;
• applying the pencil beam of particles to the target volume according to the irradiation plan and the signals;
• and
• monitoring dosage delivered to the target volume.

A method of generating an irradiation plan for irradiating a moving target volume with a pencil beam of particles, comprising:

• determining phases of motion of a target volume that exhibits motion in a plane generally transverse to a direction of a pencil beam of particles, the phases of motion being caused by a patient's physiological movement;
• defining a first field for scanning the target volume with the pencil beam of particles when the target volume is in a first phase of motion;
• defining a second field for scanning the target volume with the pencil beam of particles when the target volume is in a second phase of motion;
• generating an irradiation plan for continuously irradiating the target volume moving from the first phase to the second phase, wherein while the target volume is in the first phase of motion the first field is used for the pencil beam to scan the target volume and wherein while the target volume is in the second phase of motion the second field is used for the pencil beam to scan the target volume.

A method of generating an irradiation plan for a moving target volume with pencil beams of particles, comprising:

• determining phases of motion of a target volume that exhibits motion in a dimension generally parallel to a direction of a pencil beam of particles, the phases of motion being caused by a patient's physiological movement, wherein the target volume comprises at least a first layer and a second layer along the direction of the pencil beam of particles;
• defining a first field for irradiating the target volume in a first phase of motion, wherein at least a first pencil beam having a first energy level scans the first layer of the target volume and a second pencil beam having a second energy level scans the second layer of the target volume;
• defining a second field for irradiating the target volume in a second phase of motion, wherein the first pencil beam having the first energy level scans the second layer of the target volume or the second pencil beam having the second energy level scans the first layer of the target volume;
• generating an irradiation plan for continuously irradiating the target volume when moving from the first phase to the second phase, wherein the first pencil beam having the first energy level continuously scans the target volume when moving from the first phase to the second phase, or the second pencil beam having the second energy level continuously scans the target volume when moving from the first phase to the second phase.