Radiation Treatment Planning and Delivery for Moving Targets in the Heart

Abstract

Method and systems are disclosed for radiating a moving target inside a heart. The method includes acquiring sequential volumetric representations of an area of the heart and defining a target tissue region and/or a radiation sensitive structure region in 3D for a first of the representations. The target tissue region and/or radiation sensitive structure region are identified for another of the representations by an analysis of the area of the heart from the first representation and the other representation. Radiation beams to the target tissue region are fired in response to the identified target tissue region and/or radiation sensitive structure region from the other representation.

1 . A method of radiating a moving target, the target comprising a target tissue having blood flowing therethrough, the target tissue having a tissue surface including an inner surface bordering the blood and an outer surface, the method comprising:
 acquiring a series of computed tomography (CT) volumes encompassing the target tissue;   identifying the target in three dimensions in the acquired CT volume;   computing a treatment plan according to the identified radiation target region;   computing a dose distribution according to the computed treatment plan;   displaying a visualization of the dose distribution using a surface rendering of the tissue surface of the target tissue in three dimensions (3D); and   delivering the dose distribution to the radiation target region to treat the target.   
     
     
         2 . The method of  claim 1 , wherein the step of displaying the visualization of the dose distribution comprises at least one of: 1) volume rendering, 2) maximum intensity projection, 3) minimum intensity projection, 4) X-ray projection, 5) haptic feedback, 6) virtual fly-through, 7) stereoscopic 3D rendering, 8) virtual reality, and 9) multi-planar, oblique and curved reconstructions. 
     
     
         3 . The method of  claim 1 , wherein the treatment plan comprises a plurality of radiation beam trajectories which intersect within the radiation target region. 
     
     
         4 . The method of  claim 1 , wherein the target comprises a tumor. 
     
     
         5 . The method of  claim 1 , wherein the target comprises heart muscle and wherein the identified radiation target region is transmural. 
     
     
         6 . The method of  claim 1 , further comprising defining a radiation sensitive structure relative to the acquired CT volumes. 
     
     
         7 . The method of  claim 7 , further comprising adjusting the computed treatment plan based on the defined radiation sensitive structure. 
     
     
         8 . The method of  claim 1 , further comprising registering an electrogram with the acquired CT volumes. 
     
     
         9 . The method of  claim 1 , further comprising acquiring a pair of images of the target during treatment and registering the CT data with the pair of images to check the position of the target during treatment. 
     
     
         10 . The method of  claim 1 , wherein the identified radiation target region is non-isocentric. 
     
     
         11 . The method of  claim 1 , further comprising expanding the identified radiation target region with a margin that is based on motion estimates. 
     
     
         12 . The method of  claim 11 , wherein the margin includes the identified radiation target region during at least 80% of a target motion time. 
     
     
         13 . A non-transitory computer-readable storage medium comprising a set of computer executable instructions for treating a moving target, the target comprising a target tissue having blood flowing therethrough, the target tissue having a tissue surface including an inner surface bordering the blood and an outer surface, wherein execution of the instructions by a computer processor causes the processor to carry out the steps of:
 receiving a series of computed tomography (CT) volumes of the target tissue;   receiving user input defining the target in three dimensions relative to the acquired CT volumes;   computing a treatment plan according to the identified radiation target region;   computing a dose distribution according to the computed treatment plan;   displaying on a display device a dose distribution using a surface rendering of the tissue surface of the target tissue in three dimensions (3D); and   delivering the dose distribution to the radiation target region to treat the target.   
     
     
         14 . The non-transitory computer-readable storage medium of  claim 13 , wherein the processor carries out the step of displaying the dose distribution by utilizing at least one of: 1) volume rendering, 2) maximum intensity projection, 3) minimum intensity projection, 4) X-ray projection, 5) haptic feedback, 6) virtual fly-through, 7) stereoscopic 3D rendering, 8) virtual reality, and 9) multi-planar, oblique and curved reconstructions. 
     
     
         15 . The non-transitory computer-readable storage medium of  claim 13 , wherein the treatment plan comprises a plurality of radiation beam trajectories which intersect within the radiation target region. 
     
     
         16 . The non-transitory computer-readable storage medium of  claim 13 , wherein the processor further carries out a step of receiving user input defining a radiation sensitive structure relative to the acquired CT volumes. 
     
     
         17 . The non-transitory computer-readable storage medium of  claim 16 , wherein the processor further carries out a step of adjusting the computed treatment plan based on the user defined radiation sensitive structure. 
     
     
         18 . The non-transitory computer-readable storage medium of  claim 13 , wherein the processor further carries out a step of registering an electrogram with the acquired CT volumes. 
     
     
         19 . The non-transitory computer-readable storage medium of  claim 13 , wherein the processor further carries out a step of receiving a pair of images of the target during treatment and a step of registering the CT data with the pair of images to check the position of the target during treatment. 
     
     
         20 . The non-transitory computer-readable storage medium of  claim 13 , wherein the processor further carries out a step of expanding the identified radiation target region with a margin that is based on motion estimates. 
     
     
         21 . A system for radiating a moving target inside a tissue or on a blood vessel, the system comprising:
 an image receiving apparatus for receiving CT volumes of the target vicinity;   a user input device for receiving user input defining a radiation target region relative to received CT volumes;   a processor coupled with the image receiving apparatus and the user input device, the processor configured to:
 i) compute a treatment plan according to received user input defining the radiation target region, 
 ii) compute a dose distribution according to the computed treatment plan; 
   a display coupled with the processor for displaying the dose distribution using a surface rendering in three dimensions (3D); and   a radiation delivery device coupled with the processor, the radiation delivery device configured to deliver radiation to the target region according to the computed dose distribution.   
     
     
         22 . The system of  claim 21 , wherein the user input device is further configured to receive user input defining a radiation sensitive structure relative to the acquired CT volumes of the target vicinity. 
     
     
         23 . The system of  claim 22 , wherein the processor is further configured to adjust the computed treatment plan based on the user defined radiation sensitive structure. 
     
     
         24 . The system of  claim 21 , wherein the processor is further configured to register an electrogram with the acquired CT volumes. 
     
     
         25 . The system of  claim 21 , further comprising an image guidance system, the image guidance system configured to acquire a pair of images of the target during treatment and to register the CT data with the pair of images to check the position of the target during treatment.