Target Tracking for image-guided radiation treatment

A method for image guided radiation treatment of a body part, comprising:

• positioning the body part into a first treatment alignment relative to an image guided radiation treatment (IGRT) apparatus, said positioning including comparing (i) at least one two-dimensional stereotactic digitally reconstructed radiograph (DRR) image derived from a reference CT volume of the body part to (ii) at least one acquired two-dimensional stereotactic x-ray image of the body part obtained during said positioning;
• acquiring a first tomosynthesis image data set of said body part with said body part substantially in said first treatment alignment;
• acquiring at least one subsequent tomosynthesis data set of said body part subsequent to said acquiring said first tomosynthesis image data set;
• processing said at least one subsequent tomosynthesis image data set in conjunction with said first tomosynthesis data set to compute an in-treatment alignment variation of said body part;
• and
• delivering treatment radiation to the body part based at least in part on said computed in-treatment alignment variation.

A method for image guided radiation treatment of a body part by an image-guided radiation treatment (IGRT) apparatus, the IGRT apparatus including a treatment guidance imaging system having a known geometry relative to a first reference frame, the treatment guidance imaging system including a tomosynthesis imaging system having a known geometry relative to said first reference frame, the method comprising:

• receiving a pre-acquired planning image data set of the body part acquired in a second reference frame generally independent of said first reference frame;
• acquiring an initial diagnostic image data set of the body part in said first reference frame using said treatment guidance imaging system;
• computing a first registration between said initial diagnostic image data set and said planning image data set;
• acquiring an initial tomosynthesis image data set of said body part in said first reference frame using said tomosynthesis imaging system, said initial tomosynthesis image data set having an inherent registration with said initial diagnostic image data set;
• acquiring a subsequent tomosynthesis image data set in said first reference frame using said tomosynthesis imaging system at a time subsequent to said initial tomosynthesis image data set acquisition;
• computing a second registration between said subsequent tomosynthesis image data set and said initial tomosynthesis image data set;
• and
• delivering treatment radiation to the body part based at least in part on information derived from (i) said first registration, (ii) said inherent registration, and (iii) said second registration.

A method for image guided radiation treatment of a body part by an image-guided radiation treatment (IGRT) apparatus, the IGRT apparatus including a tomosynthesis imaging system having a known geometry relative to a reference frame of the IGRT apparatus, the method comprising:

• receiving a pre-acquired image data set of the body part acquired in a reference frame generally independent of the reference frame of the IGRT apparatus;
• acquiring an initial tomosynthesis image data set of the body part using said tomosynthesis imaging system while said body part is in an initial treatment position relative to the (IGRT) apparatus;
• computing a first registration between said initial tomosynthesis image data set and said pre-acquired image data set;
• acquiring a subsequent tomosynthesis image data set using said tomosynthesis imaging system at a time subsequent to said initial tomosynthesis image data set acquisition;
• computing a second registration between said subsequent tomosynthesis image data set and said initial tomosynthesis image data set;
• and
• delivering treatment radiation to the body part based at least in part on information derived from (i) said first registration between said initial tomosynthesis image data set and said pre-acquired image data set and (ii) said second registration between said subsequent tomosynthesis image data set and said initial tomosynthesis image data set.

An image-guided radiation treatment (IGRT) system, having a first reference frame, comprising:

• a tomosynthesis imaging system having a known geometry relative to the first reference frame, the tomosynthesis imaging system to:
• acquire an initial tomosynthesis image data set of a body part while said body part is in an initial treatment position relative to the IGRT system;
• and
• acquire a subsequent tomosynthesis image data set at a time subsequent to said initial tomosynthesis image data set acquisition;
• a system controller to:
• receive a pre-acquired image data set of the body part acquired in a second reference frame generally independent of the first reference frame;
• compute a first registration between said initial tomosynthesis image data set and said pre-acquired image data set;
• and
• compute a second registration between said subsequent tomosynthesis image data set and said initial tomosynthesis image data set;
• and
• a radiation treatment source to deliver treatment radiation to the body part based at least in part on information derived from (i) said first registration between said initial tomosynthesis image data set and said pre-acquired image data set and (ii) said second registration between said subsequent tomosynthesis image data set and said initial tomosynthesis image data set.

A system comprising:

• a diagnostic imaging system to acquire a diagnostic image of a patient in a first coordinate system, wherein said diagnostic image comprises at least a portion of a target;
• a tomosysnthesis imaging system to:
• acquire a first tomosynthesis image of the patient in the first coordinate system, wherein the first tomosynthesis image is inherently registered with the diagnostic image, and wherein the first tomosynthesis image comprises at least a portion of the target;
• and
• acquire a second tomosynthesis image of said patient, wherein said second tomosynthesis image comprises at least a portion of the target;
• and
• a system controller to:
• receive a planning image of the patient including the target, wherein the planning image has a second coordinate system;
• register the diagnostic image with the planning image to obtain an alignment transformation between the second coordinate system and the first coordinate system;
• and
• register said second tomosynthesis image with said first tomosynthesis image to compute an intrafraction transformation between the second coordinate system and the first coordinate system, wherein said intrafraction transformation determines an approximate intrafraction location of the target in the first coordinate system relative to the second coordinate system.