Method and apparatus for controlling a radiation treatment field

A system for marking a radiation treatment curve on a patient prior to radiation therapy, said system comprising:

• a simulation apparatus including an X-ray apparatus for generating an X-ray image of a region of a patient;
• a host computer;
• means for inputting a radiation treatment area curve determined from an X-ray image into the host computer;
• projection display means coupled to said host computer for generating a projection image having transmissive areas corresponding to said treatment curve in response to signals received from said host computer;
• and
• light projection means disposed in said simulation apparatus for projecting light through said projection display means onto the treatment area of the patient, wherein the treatment curve is projected onto the patient, namely on skin over the treatment area, and the patient skin is marked with the outline of said curve.

A system for performing radiation treatment on a patient, the system comprising:

• a simulation apparatus including an X-ray apparatus for generating an X-ray image of a region of a patient;
• a host computer;
• means for inputting a radiation treatment area curve determined from the X-ray image which defines a radiation treatment area into said host computer;
• projection display means coupled to said host computer for generating a projection image having transmissive areas corresponding to said treatment curve in response to signals received from said host computer;
• light projection means disposed in said simulation apparatus for projecting light through said projection display means onto the treatment area of the patient, whereby the treatment curve is projected onto the patient, and the patient skin is marked with the outline of said curve;
• radiation therapy apparatus including a multi-leaf collimator;
• means for transmitting signals defining said treatment curve from said host computer to the multi-leaf collimator, whereby the collimator opening will conform to the treatment area;
• means for projecting light through the multi-leaf collimator onto the marked area of said patient to verify that the multi-leaf collimator is producing the same shaped treatment area region as marked on the patient and also to verify that the patient is correctly positioned;
• and
• means for transmitting a radiation therapy beam through said multi-leaf collimator onto said patient, whereby the therapy beam conforms to the curve marked on said patient.

A method of marking a treatment curve on a patient prior to radiation therapy, said method comprising the steps of:

• generating a radiological image of a region of a patient in a simulator;
• producing a curve on the radiological image of a region of a patient in a simulator;
• producing a curve on the radiological image defining the location and shape of a desired radiation treatment area;
• reproducing said curve on a transmissive surface with a radio-opaque ink;
• projecting fight through the transmissive surface onto the treatment area of the patient;
• and
• marking the patient's skin to define the treatment area.

A method of marking a treatment curve on a patient prior to radiation therapy, said method comprising the steps of:

• generating a radiological image of a region of a patient in a simulator;
• producing a curve on the radiological image of a region of a patient in a simulator;
• producing a curve on the radiological image defining the location and shape of a desired radiation treatment area;
• reproducing said curve on a transmissive surface with an LCD plate;
• projecting light through the LCD plate onto the treatment area of the patient;
• and
• marking the patient's skin to define the treatment area.