Delivery modification system for radiation therapy

A method of operating a radiation therapy machine providing a radiation beam of individually energy and/or fluence modulated radiation rays directed generally along a beam axis and spaced apart perpendicular to the beam axis, the radiation beam axis positionable at a range of angles about a patient, the method comprising the steps of:

• (a) accepting a treatment sinogram of rows and columns providing energy and/or fluence of different rays for a given angle of the radiation beam axis, in rows, and energy and/or fluence of a given ray for different angles of the beam axis, in columns, for a patient at a first position;
• (b) during radiation treatment using the treatment sinogram;
• (i) detecting patient movement data indicating patient motion from the first position to a second position;
• (ii) directly modifying the treatment sinogram according to the detected patient motion;
• (c) continuing the radiation treatment using the treatment sinogram as modified by step (b)(ii);
• whereby rapid adjustments to the treatment plan may be effected.

A method of operating a radiation therapy machine providing a radiation beam of individually energy modulated radiation rays directed generally along a beam axis and spaced apart perpendicular to the beam axis, the radiation beam axis positionable at a range of angles about a patient, the method comprising the steps of:

• (a) preparing a library of partial sinograms of rows and columns, providing energy and/or fluence of different rays for a given angle of the radiation beam axis, in rows, and energy and/or fluence of a given ray for different angles of the beam axis, in columns, each partial sinogram corresponding to one of a variety of patient elements in first modes;
• (b) arranging combinations of a set of representations of the patient elements to second modes so as to model a given patient requiring radiation treatment;
• (c) determining for each of the patient elements of the set alteration data indicating changes in the patient elements between the first and second modes;
• (d) modifying the partial sinograms of each of the patient elements of the set according to the alteration data;
• and
• (e) combining the modified partial sinograms to provide a treatment sinogram of the patient.