Patient positioning assembly for therapeutic radiation system

Abstract

An apparatus and method for moving a support device with respect to a radiation source in at least three degrees of freedom to align a treatment target with respect to the radiation source.

1 . A method, comprising: 
 providing a support device;    providing a radiation source; and    moving the support device with respect to the radiation source in at least three degrees of freedom to align a treatment target with respect to the radiation source.    
     
     
         2 . The method of  claim 1 , wherein moving the support device comprises: 
 determining a near real-time position of the treatment target with respect to a treatment coordinate system; and    determining one or more corrective motions of the support device to move the support device from the near real-time position with respect to the radiation source to align the treatment target with respect to the radiation source.    
     
     
         3 . The method of  claim 2 , wherein moving the support device comprises determining a position of the treatment target with respect to a pre-treatment coordinate system, the treatment coordinate system having a predetermined relationship to the pre-treatment coordinate system, wherein determining the one or more corrective motions comprises moving the support device with respect to the radiation source to substantially match the position of the treatment target with respect to the pre-treatment coordinate system with the determined near real-time position with respect to the treatment coordinate system.  
     
     
         4 . The method of  claim 3 , wherein moving the support device comprises: 
 determining an orientation of the treatment target with respect to the pre-treatment coordinate system; and    determining an orientation of the treatment target with respect to the treatment coordinate system, and wherein determining the one or more corrective motions comprises moving the support device with respect to the radiation source to substantially match the position and orientation of the treatment target with respect to the pre-treatment coordinate system with the determined near real-time position and orientation of the treatment target with respect to the treatment coordinate system.    
     
     
         5 . The method of  claim 1 , wherein moving the support device comprises: 
 determining an orientation of the treatment target with respect to a treatment coordinate system; and    determining one or more corrective motions of the support device to move the support device with respect to the radiation source using the orientation of the treatment target to align the treatment target with respect to the radiation source.    
     
     
         6 . The method of  claim 5 , wherein moving the support device comprises determining an orientation of the treatment target with respect to a pre-treatment coordinate system, the treatment coordinate system having a predetermined relationship to the pre-treatment coordinate system, wherein determining the one or more corrective motions comprises moving the support device with respect to the radiation source to substantially match the orientation of the treatment target with respect to the pre-treatment coordinate system with the determined orientation with respect to the treatment coordinate system.  
     
     
         7 . The method of  claim 3 , further comprising: 
 receiving pre-treatment scan data representative of one or more pre-treatment scans of the treatment target within a patient on the support device, the one or more pre-treatment scans showing the position of the treatment target with respect to the pre-treatment coordinate system;    receiving near real-time image data representative of one or more near real-time images including the position of the treatment target with respect to the treatment coordinate system; and    generating at least one motion command signal for implementing the one or more corrective motions of the support device to move the support device to substantially match the position of the treatment target as shown in the pre-treatment scan data of the treatment target with the position of the treatment target of the near real-time image data.    
     
     
         8 . The method of  claim 7 , wherein generating the at least one motion command signal comprises comparing the position of the treatment target, as shown in the near real-time image data, with the position of the treatment target as shown in the pre-treatment scan data.  
     
     
         9 . The method of  claim 7 , wherein the one or more pre-treatment scans shows the position and an orientation of the treatment target with respect to the pre-treatment coordinate system, wherein the one or more near real-time images show the position and an orientation of the treatment target with respect to the treatment coordinate system, and wherein generating the at least one motion command signal comprises moving the support device to substantially match the position and orientation of the treatment target as shown in the pre-treatment scan data with the position and orientation of the treatment target of the near real-time image data.  
     
     
         10 . The method of  claim 9 , wherein generating the at least one motion command signal comprises comparing the position and orientation of the treatment target, as shown in the near real-time image data, with the position and orientation of the treatment target as shown in the pre-treatment scan data.  
     
     
         11 . The method of  claim 1 , wherein moving the support device comprises positioning the support device to a treatment position.  
     
     
         12 . The method of  claim 11 , wherein the treatment position is where the treatment target is within an imaging field of view of an imaging system.  
     
     
         13 . The method of  claim 11 , further comprising manually adjusting the support device so that the treatment target is within an imaging field of view of an imaging system.  
     
     
         14 . The method of  claim 13 , wherein manually adjusting the support device comprises using a handheld remote control unit.  
     
     
         15 . The method of  claim 1 , wherein moving the support device comprises: 
 making an initial correction of the support device to align the treatment target with respect to the radiation source;    taking one or more additional images of the treatment target; and    performing one or more additional corrections from the one or more additional images to align the treatment target with respect to the radiation source.    
     
     
         16 . The method of  claim 15 , wherein taking one or more additional images and performing one or more additional corrections are repeated until at least one of the following conditions is met: 
 a specific amount of images have been taken; or    residual corrections to align the treatment target with respect to the radiation source fall below a specified limit.    
     
     
         17 . The method of  claim 15 , further comprising positioning the support device so that the treatment target is within an imaging field of view of an imaging system before imaging the treatment target at the initial treatment position.  
     
     
         18 . The method of  claim 7 , wherein generating the at least one motion command signal further comprises: 
 calculating an amount of translations and rotations required in order for the position of the treatment target, as shown in the near real-time images, to substantially match the position of the treatment target, as shown in the pre-treatment scan data; and    converting the amount of translations and rotations into one or more units of motion of the support device.    
     
     
         19 . The method of  claim 7 , wherein moving the support device comprises moving the support device with respect to the radiation source using at least one actuator.  
     
     
         20 . The method of  claim 7 , wherein moving the support device comprises moving the support device with respect to the radiation source using an external device, wherein the external device is a robot, and wherein the robot includes an articulated arm assembly.  
     
     
         21 . The method of  claim 7 , further comprising providing a user interface coupled to the support device, the user interface including one or more user-selectable functions.  
     
     
         22 . The method of  claim 21 , wherein the one or more user-selectable functions comprise at least one of: 
 activating an imaging system so as to initiate the acquisition of the one or more near real-time images of the treatment target;    adjusting one ore more imaging parameters of the imaging system;    moving the support device to at least one of: 
 a first pre-programmed position corresponding to a loading position for mounting the patient onto the support device; and  
 a second pre-programmed position corresponding to a treatment position in which the patient was treated at a time period prior to a current treatment;  
   displaying to the user a sequence of translations and rotations corresponding to the one or more corrective motions of the support device for moving the support device with respect to the radiation source;    modifying the sequence of translations and rotations;    comparing the translations and rotations with respective pre-specified limits for each translation and rotation;    modifying one or more of the pre-specified limits; or    activating a treatment beam generator of a treatment apparatus, having the radiation source, to initiate treatment delivery, upon verification that the translations and rotations identified by the motion command signal fall below the pre-specified limits.    
     
     
         23 . The method of  claim 22 , wherein the imaging parameters comprise at least one of: 
 an intensity of x-rays in one or more imaging beams generated by the imaging system;    a spectral distribution of the x-rays in the imaging beams;    energy of x-rays in imaging beam;    selection and de-selection of fiducials;    one or more rigid body parameters; or    a number of near real-time images to be acquired.    
     
     
         24 . The method of  claim 21 , wherein the user interface interactively controls the position of the support device for substantially aligning the position and orientation of the treatment target as shown in the pre-treatment scan data of the treatment target.  
     
     
         25 . An apparatus, comprising: 
 a support device; and    means for moving the support device with respect to a radiation source in at least three degrees of freedom to align a treatment target with respect to the radiation source.    
     
     
         26 . The apparatus of  claim 25 , further comprising means for generating one or more corrective motions of the support device to move the support device to substantially match a position and orientation of the treatment target as shown in a pre-treatment scan of the treatment target with a position and orientation of the treatment target in a near real-time image data.