DRR generation and enhancement using a dedicated graphics device

Abstract

DRR generation and enhancement using a dedicated graphics device are described herein. In one embodiment, an example of a process for generating DRR (digitally reconstructed radiography) images includes, but is not limited to, loading a volume rendering program into a graphics device, the volume rendering program representing a predetermined algorithm according to a non-linear attenuation model. In response to 3D scan data, the graphics device is invoked to execute the volume rendering program to perform at least a portion of volume rendering operations on at least a portion of the 3D scan data, which may include modifying the 3D scan data according to the predetermined algorithm to compensate for a difference between a first attenuation of an object with respect to a second attenuation associating a known intensity of the object. Other methods and apparatuses are also described.

1 . A computer implemented method for generating DRR (digitally reconstructed radiography) images, the method comprising: 
 loading a volume rendering program into a graphics device, the volume rendering program representing a predetermined algorithm according to a non-linear attenuation model; and    in response to 3D scan data, invoking the graphics device to execute the volume rendering program to perform at least a portion of volume rendering operations on at least a portion of the 3D scan data, including modifying the 3D scan data according to the predetermined algorithm to compensate for a difference between a first attenuation of an object with respect to a second attenuation associating a known intensity of the object.    
     
     
         2 . The method of  claim 1 , wherein the volume rendering operations further comprise: 
 casting a plurality of hypothetical rays through the modified 3D scan data from at least one of the known intensity, a known orientation, and an angle;    integrating the 3D scan data along with each hypothetical ray; and    projecting integrated values of 3D scan data onto an image plane.    
     
     
         3 . The method of  claim 1 , wherein the 3D scan data comprises at least one of CT, MRI, PET, and ultrasound scan data.  
     
     
         4 . The method of  claim 1 , wherein the 3D scan data comprises a plurality of CT numbers representing an image intensity of corresponding 3D CT voxels, wherein each CT voxel represents a corresponding volume element of the object, and wherein each CT number represents an attenuated intensity of an X-ray CT beam that has been generated at a CT scan energy level and that has traversed the corresponding volume element of an anatomical region.  
     
     
         5 . The method of  claim 4 , wherein each CT voxel is disposed within one of a plurality of axial voxel slices, each axial voxel slice representing a corresponding axial slice of the object.  
     
     
         6 . The method of  claim 1 , wherein the predetermined algorithm is performed according to a following algorithm:  
           C ( x,y,z )= aC   0 ( x,y,z ) e   bC     0     (x,y,z)    wherein C(x,y,z) represents the modified CT number of a 3D CT voxel having a location (x,y,z), wherein a and b represent weighting coefficients, and wherein C 0 (x,y,z) represents the unmodified CT number based on a linear attenuation model of a 3D CT voxel having a location (x,y,z).    
     
     
         7 . A machine-readable medium having executable code to cause a machine to perform a method for generating DRR images, the method comprising: 
 loading a volume rendering program into a graphics device, the volume rendering program representing a predetermined algorithm according to a non-linear attenuation model; and    in response to 3D scan data, invoking the graphics device to execute the volume rendering program to perform at least a portion of volume rendering operations on at least a portion of the 3D scan data, including modifying the 3D scan data according to the predetermined algorithm to compensate for a difference between a first attenuation of an object with respect to a second attenuation associating a known intensity of the object.    
     
     
         8 . The machine-readable medium of  claim 7 , wherein the volume rendering operations further comprise: 
 casting a plurality of hypothetical rays through the modified 3D scan data from at least one of the known intensity, a known orientation, and an angle;    integrating the 3D scan data along with each hypothetical ray; and    projecting integrated values of 3D scan data onto an image plane.    
     
     
         9 . The machine-readable medium of  claim 7 , wherein the 3D scan data comprises at least one of CT, MRI, PET, and ultrasound scan data.  
     
     
         10 . The machine-readable medium of  claim 7 , wherein the 3D scan data comprises a plurality of CT numbers representing an image intensity of corresponding 3D CT voxels, wherein each CT voxel represents a corresponding volume element of the object, and wherein each CT number represents an attenuated intensity of an X-ray CT beam that has been generated at a CT scan energy level and that has traversed the corresponding volume element of an anatomical region.  
     
     
         11 . The machine-readable medium of  claim 10 , wherein each CT voxel is disposed within one of a plurality of axial voxel slices, each axial voxel slice representing a corresponding axial slice of the object.  
     
     
         12 . The machine-readable medium of  claim 7 , wherein the predetermined algorithm is performed according to a following algorithm:  
           C ( x,y,z )= aC   0 ( x,y,z ) e   bC0(x,y,z)    wherein C(x,y,z) represents the modified CT number of a 3D CT voxel having a location (x,y,z), wherein a and b represent weighting coefficients, and wherein C 0 (x,y,z) represents the un-modified CT number based on a linear attenuation model of a 3D CT voxel having a location (x,y,z).    
     
     
         13 . A data processing system, comprising: 
 a processor; 
 a memory coupled to the processor via a bus; and  
 a graphics device coupled to the bus, wherein the memory stores instructions when executed from the memory, cause the processor to load a volume rendering program into the graphics device, the volume rendering program representing a predetermined algorithm according to a non-linear attenuation model, and  
 in response to 3D scan data, invoke the graphics device to execute the volume rendering program to perform at least a portion of volume rendering operations on at least a portion of the 3D scan data, including modifying the 3D scan data according to the predetermined algorithm to compensate for a difference between a first attenuation of an object with respect to a second attenuation associating a known intensity of the object.  
   
     
     
         14 . An apparatus for generating DRR images, comprising: 
 means for loading a volume rendering program into a graphics device, the volume rendering program representing a predetermined algorithm according to a non-linear attenuation model; and    means for, in response to 3D scan data, invoking the graphics device to execute the volume rendering program to perform at least a portion of volume rendering operations on at least a portion of the 3D scan data, including modifying the 3D scan data according to the predetermined algorithm to compensate for a difference between a first attenuation of an object with respect to a second attenuation associating a known intensity of the object.