Verifying Lesion Characteristics Using Beam Shapes

Abstract

A patient's lesion is localized for the purpose of administering radiation treatment by obtaining a beam shape representation along one or more beam directions of a radiation treatment device. An image corresponding to the lesion is obtained from each beam direction, and the beam shape and image are fixed to a common coordinate system to facilitate alignment.

1 . A method for improved spatial localization of a patient's lesion for the purpose of administering radiation treatment, the method comprising the steps of:
 (a) obtaining a first beam shape representation along a direction of a first beam of a treatment device;   (b) obtaining an image corresponding to the lesion from the direction of the beam of the treatment device; and   (c) fixing the first beam shape and the image to a common coordinate system in order to facilitate alignment.   
     
     
         2 . The method of  claim 1  wherein the treatment device includes one or more beam-shielding devices that affect the beam shape. 
     
     
         3 . The method of  claim 2  wherein the beam-shielding device is a MLC. 
     
     
         4 . The method of  claim 3  wherein the first beam shape is based, at least in part, on the physical arrangement of leaves in the MLC. 
     
     
         5 . The method of  claim 4  wherein the first beam shape is adjusted by adjusting the positions of the leaves within the MLC. 
     
     
         6 . The method of  claim 5  further comprising adjusting leaves within the MLC in order to conform the beam shape about the lesion. 
     
     
         7 . The method of  claim 6  wherein the leaves are adjusted manually. 
     
     
         8 . The method of  claim 6  wherein the leaves are adjusted programmatically. 
     
     
         9 . The method of  claim 6  wherein the adjustment is made during a treatment planning session. 
     
     
         10 . The method of  claim 1  wherein the image is one or more images selected from the group of a three-dimensional ultrasound image, a CT image, an MRI image, and a PET image acquired after planning for purposes of treatment. 
     
     
         11 . The method of  claim 1  wherein the image corresponding to the lesion is a three-dimensional image. 
     
     
         12 . The method of  claim 11  further comprising rendering the three-dimensional image of the lesion as a set of surface elements. 
     
     
         13 . The method of  claim 1  further comprising adjusting the position of the patient so that the beam shape representation substantially encompasses the lesion. 
     
     
         14 . The method of  claim 1  further comprising aligning the image with the first beam shape representation so that the lesion is substantially encompassed within the shape. 
     
     
         15 . The method of  claim 14  further comprising adjusting the position of the patient in accordance with the alignment so that the beam shape representation substantially encompasses the lesion. 
     
     
         16 . The method of  claim 1  further comprising altering the beam shape in preparing for treatment delivery such that beam shape substantially encompasses the lesion. 
     
     
         17 . The method of  claim 1  where the image is three-dimensional, further comprising:
 (d) obtaining one or more additional beam shape representations, each from a separate direction; and   (e) fixing each of the additional beam shape representations and the three-dimensional image to the common coordinate system.   
     
     
         18 . The method of  claim 17  wherein the beam shape representations comprise a beam shape intersection volume. 
     
     
         19 . The method of  claim 18  further comprising aligning the beam shape intersection volume and the image so that the lesion is substantially encompassed within the intersection volume. 
     
     
         20 . The method of  claim 19  further comprising adjusting the position of the patient in accordance with the alignment so that the beam intersection volume substantially encompasses the lesion. 
     
     
         21 . The method of  claim 1  wherein the beam shape is generated during a treatment planning session. 
     
     
         22 . The method of  claim 1  wherein the coordinate system is established using a laser system arranged within a treatment delivery room. 
     
     
         23 . The method of  claim 1  wherein the image is fixed to the coordinate system during a treatment delivery session. 
     
     
         24 . A method for positioning a patient for the administration of radiation treatment of a lesion, the method comprising the steps of:
 (a) providing a treatment device emitting at least one beam, each beam having a beam shape;   (b) generating a three-dimensional ultrasound image of the lesion;   (c) fixing the beam shapes to a treatment coordinate system;   (d) fixing the ultra-sound image to the treatment coordinate system;   (e) superimposing the beam shapes and the ultrasound image based, at least in part, on the treatment coordinate system; and   (f) adjusting the position of the patient such that the ultrasound image is substantially encompassed by the beam shapes.   
     
     
         25 . The method of  claim 24  wherein the treatment device includes, for each beam, at least one beam-shielding device that affects the shape of the beam shape. 
     
     
         26 . The method of  claim 25  wherein the beam-shielding device is a MLC. 
     
     
         27 . The method of  claim 26  wherein each beam shape is based, at least in part, on the physical arrangement of leaves in the MLC as determined during a treatment planning session. 
     
     
         28 . The method of  claim 27  further comprising for each beam, adjusting leaves within the MLC in order to conform the beam shape about the lesion. 
     
     
         29 . The method of  claim 28  wherein the leaves are adjusted manually. 
     
     
         30 . The method of  claim 28  wherein the leaves are adjusted programmatically. 
     
     
         31 . The method of  claim 24  further comprising rendering the three-dimensional ultrasound image of the lesion as a set of surface elements. 
     
     
         32 . A system for positioning a patient for the administration of radiation treatment of a lesion, the system comprising:
 (a) a register for establishing one or more beam shape representations taken from one or more perspectives of a treatment device;   (b) a processor for determining an alignment of the one or more beam shape representations and an image corresponding to the lesion using a common coordinate reference system such that the image corresponding to the lesion is substantially encompassed by the one or more beam shape images; and   (c) a controller for controlling a patient support device in accordance with the alignment.   
     
     
         33 . The system of  claim 32  wherein the treatment device includes one or more beam-shielding devices that affect the beam shape. 
     
     
         34 . The system of  claim 33  wherein the beam-shielding device is a MLC. 
     
     
         35 . The system of  claim 34  wherein the one or more beam shape representations are based, at least in part, on the physical arrangement of leaves in the MLC as determined during a treatment planning session. 
     
     
         36 . The system of  claim 35  wherein the one or more beam shape representations are adjusted by adjusting the positions of the leaves within the MLC. 
     
     
         37 . The system of  claim 36  wherein the leaves are adjusted manually. 
     
     
         38 . The system of  claim 36  wherein the leaves are adjusted programmatically. 
     
     
         39 . The system of  claim 36  wherein the adjustments are made during a treatment planning session. 
     
     
         40 . The system of  claim 32  wherein the image is one or more images selected from the group of a three-dimensional ultrasound image, a CT image, an MRI image, and a PET image acquired after planning for purposes of treatment. 
     
     
         41 . The system of  claim 32  wherein the image corresponding to the lesion is a three-dimensional image and the processor segments the image into a set of surface elements. 
     
     
         42 . The system of  claim 32  wherein the controller adjusts the position of the patient support device so that the beam shape representation substantially encompasses the lesion. 
     
     
         43 . The system of  claim 32  further comprising a laser system arranged within a treatment delivery room for establishing the common coordinate reference system. 
     
     
         44 . The system of  claim 32  wherein the one or more beam shape representations comprise an intersection MLC volume. 
     
     
         45 . A system for improved spatial validation of the position of a patient's lesion for the purpose of administering radiation treatment, comprising:
 (a) means for obtaining a one or more beam shape representations along a direction of a first beam of a treatment device;   (b) means for obtaining an image corresponding to a patient's lesion from the direction of the beam of the treatment device; and   (c) means for fixing the first beam shape representations and image to a common coordinate system.   
     
     
         46 . The system of  claim 45  further comprising means for adjusting beam one or more shielding devices within the treatment device in order to conform the beam shape representations about the lesion. 
     
     
         47 . The system of  claim 46  wherein the beams are adjusted manually. 
     
     
         48 . The system of  claim 46  wherein the beams are adjusted programmatically. 
     
     
         49 . The system of  claim 45  further comprising means for segmenting the image corresponding to a patient's lesion into a set of surface elements. 
     
     
         50 . The system of  claim 45  wherein the one or more beam shape representations comprise an intersection volume. 
     
     
         51 . The system of  claim 45  further comprising means for adjusting the position of the patient so that the one or more beam shape representations substantially encompasses the lesion. 
     
     
         52 . The system of  claim 45  further comprising means for aligning the image with the one or more beam shape representations so that the image corresponding to the lesion is substantially encompassed within the beam shape representation. 
     
     
         53 . The system of  claim 52  further comprising means for adjusting the position of the patient in accordance with the alignment so that the beam shape representations substantially encompasses the lesion.