Patent ID: 8184772

Claim:
A method of treating tissue at a target zone deep to a surface of a patient's body by emitting, from an x-ray source having a system axis defined in a global coordinate system, a collimated x-ray beam having a beam axis defined in the global coordinate system, said method comprising: (a) determining a reference axis defined relative to the patient's body, the reference axis being in the global coordinate system; (b) determining a treatment axis that intersects the target zone, the treatment axis being in the global coordinate system; (c) positioning the x-ray source at a first position with respect to the system axis, such that the beam axis intersects the treatment axis at a first treatment site within the target zone and such that the beam axis intersects the surface of the patient's body at a first location; (d) emitting an x-ray beam toward the target zone along the beam axis, to irradiate the target zone with a first radiation dose; (e) rotating the x-ray source about the system axis to a second position with respect to the system axis, such that the beam axis intersects the treatment axis at a second treatment site within the target zone and such that the beam axis intersects the surface of the patient's body at a second location that is separated from the first location by a first distance; and (f) emitting an x-ray beam toward the target zone along the beam axis, to irradiate the target zone with a second radiation dose.