Radiation treatment delivery system with outwardly movable radiation treatment head extending from ring gantry

Abstract

An image-guided radiation treatment (IGRT) system and method are described. An IGRT apparatus having a gantry frame including a ring member with the ring member being rotatable around a substantially horizontal, longitudinally extending central axis, and the ring member having first and second horizontally opposing ends. The IGRT apparatus further includes a radiation treatment head coupled to the ring member by an arm member with the arm member being connected to the ring member at an arm member base. The arm member extends outwardly from the first end of the ring member in a direction away from the second end and is supported only by the arm member base, and the radiation treatment head is dynamically movable in at least a longitudinal direction toward and away from the first end of the ring member.

What is claimed is: 
     
         1 . An image-guided radiation treatment (IGRT) apparatus, comprising:
 a gantry frame including a ring member, the ring member being rotatable around a substantially horizontal, longitudinally extending central axis, said ring member having first and second horizontally opposing ends; and   a radiation treatment head coupled to said ring member in an outwardly movable manner by an arm member extending outwardly from said first end of said ring member in a direction away from said second end, wherein said radiation treatment head is outwardly movable in at least a longitudinal direction toward and away from said first end of said ring member.   
     
     
         2 . The IGRT apparatus of  claim 1 , said IGRT apparatus accommodating a treatment center at any of a plurality of longitudinal locations along the central axis by virtue of said longitudinal movability of the radiation treatment head, wherein said radiation treatment head is dynamically tiltable relative to a transverse treatment center plane for any of said longitudinal treatment center locations, wherein said IGRT apparatus configured to provide noncoplanar radiation treatment for any of said longitudinal treatment center locations. 
     
     
         3 . The IGRT apparatus of  claim 2 , wherein said arm member comprises an articulated robot arm having a shoulder joint connected to said ring member, said radiation treatment head being coupled to said articulated robot arm at a distal end thereof opposite said shoulder joint. 
     
     
         4 . The IGRT apparatus of  claim 3 , wherein said articulated robot arm includes a first arm segment coupled between said shoulder joint and an elbow joint and a second arm segment coupled between said elbow joint and a three degree-of-freedom wrist member, said radiation treatment head being coupled to and supported by said wrist member. 
     
     
         5 . The IGRT apparatus of  claim 3 , wherein said articulated robot arm is configured such that said radiation treatment head is dynamically movable into an apex treatment position in which a radiation treatment beam emanates therefrom at or near the central axis and is substantially parallel to the central axis. 
     
     
         6 . The IGRT apparatus of  claim 2 , wherein said radiation treatment head is dynamically tiltable along at least two tilt axes for any of said longitudinal treatment center locations, whereby said IGRT apparatus is configured accommodate off-central-axis treatment centers for any of said longitudinal treatment center locations. 
     
     
         7 . The IGRT apparatus of  claim 1 , said arm member being a first arm member, the IGRT apparatus further comprising a portal imaging detector coupled to said ring member in an outwardly movable manner by a second arm member extending outwardly from said ring member on a same side of said gantry frame as said radiation treatment head, said portal imaging detector being disposed generally opposite said radiation treatment head relative to said central axis. 
     
     
         8 . The IGRT apparatus of  claim 1 , said arm member being a first arm member, the IGRT apparatus further comprising:
 a kV imaging source coupled to said gantry frame in an outwardly movable manner by a second arm member extending outwardly from said gantry frame on a same side thereof as said radiation treatment head; and   a kV imaging detector coupled to said gantry frame in an outwardly movable manner by a third arm member extending outwardly from said gantry frame on said same side as said radiation treatment head, said kV imaging detector being disposed generally opposite said kV imaging source relative to said central axis.   
     
     
         9 . The IGRT apparatus of  claim 8 , said second and third arm members comprising respective articulated robot arms having respective shoulder joints connected to said gantry frame, said kV imaging source and kV imaging detector being coupled to said second and third arm members, respectively, at respective distal ends thereof opposite said respective shoulder joints thereof. 
     
     
         10 . The IGRT apparatus of  claim 8 , wherein said second and third arm members are coupled to said ring member such that said kV imaging source and said kV imaging detector rotate in unison with said radiation treatment head around said central axis. 
     
     
         11 . The IGRT apparatus of  claim 8 , said ring member being a first ring member, the gantry frame further including a second ring member rotatable around said central axis independently of said first ring member, wherein said second and third arm members are coupled to said second ring member such that said kV imaging source and said kV imaging detector rotate independently of said radiation treatment head around said central axis. 
     
     
         12 . The IGRT apparatus of  claim 11 , wherein said radiation treatment head is a LINAC configured to couple to external electrical LINAC driving circuitry using non-slip-ring electrical cabling, and wherein said kV imaging source and said kV imaging detector are configured to couple to external kV imaging driving circuitry through slip-ring electrical contacts included in said second ring member. 
     
     
         13 . The IGRT apparatus of  claim 8 , said kV imaging source and said kV imaging detector forming a first kV imaging source-detector pair, said IGRT apparatus further comprising a second kV imaging source-detector pair coupled to said gantry frame in an outwardly movable manner by fourth and fifth arm members, respectively, said first and second kV imaging source-detector pairs being mutually positioned in a stereoscopic imaging configuration around said central axis. 
     
     
         14 . The IGRT apparatus of  claim 13 , said second, third, fourth, and fifth arm members comprising respective articulated robot arms having respective shoulder joints connected to said gantry frame, said first and second kV imaging sources and first and second kV imaging detectors being coupled to second, third, fourth, and fifth arm members, respectively, at respective distal ends thereof opposite said respective shoulder joints thereof. 
     
     
         15 . The IGRT apparatus of  claim 13 , wherein said second, third, fourth, and fifth arm members are coupled to said ring member such that said first and second kV imaging source-detector pairs rotate in unison with said radiation treatment head around said central axis. 
     
     
         16 . The IGRT apparatus of  claim 13 , said ring member being a first ring member, the gantry frame further including a second ring member rotatable around said central axis independently of said first ring member, wherein said second, third, fourth, and fifth arm members are coupled to said second ring member such that said first and second kV imaging source-detector pairs rotate independently of said radiation treatment head around said central axis. 
     
     
         17 . The IGRT apparatus of  claim 1 , further comprising a high resolution collimated CT imaging apparatus disposed adjacent to said gantry frame near said second end of said ring member, said CT imaging apparatus having a central axis of rotation coincident with said central axis of said ring member and forming a common central bore with said ring member. 
     
     
         18 . A method of image guided radiation treatment (IGRT) of a body part of a patient, comprising:
 positioning the patient into a treatment position relative to an IGRT apparatus, the IGRT apparatus comprising:
 a gantry frame including a ring member, the ring member being rotatable around a substantially horizontal, longitudinally extending central axis and having first and second horizontally opposing ends; and 
 a radiation treatment head coupled to said ring member in an outwardly movable manner by an arm member extending outwardly from said first end of said ring member in a direction away from said second end, wherein said radiation treatment head is outwardly movable in at least a longitudinal direction toward and away from said first end of said ring member; 
   operating the IGRT apparatus to apply non-coplanar radiation treatment to the body part during a treatment fraction, said operating comprising rotating the ring member to a plurality of different gantry angles to move the radiation treatment head to a corresponding plurality of different treatment angles, said operating further comprising moving the radiation treatment head to a plurality of different outward distances from said first end of the ring member.   
     
     
         19 . The method of  claim 18 , wherein said positioning the patient into the treatment position comprises positioning the patent along the central axis of the ring member at a longitudinal position in which the full body of the patient is outwardly disposed relative to the first end of the ring member. 
     
     
         20 . The method of  claim 18 , said arm member comprising an articulated robot arm having a shoulder joint connected to said ring member, said radiation treatment head being coupled to said articulated robot arm at a distal end thereof opposite the shoulder joint, wherein said moving the radiation treatment head to the plurality of different outward distances comprises operating the articulated robot arm. 
     
     
         21 . The method of  claim 20 , further comprising operating the articulated robot arm to dynamically tilt the radiation treatment head to a plurality of different tilt angles relative to a transverse treatment center plane. 
     
     
         22 . The method of  claim 21 , further comprising operating the articulated robot arm to dynamically direct treatment radiation in a plurality of off-central-axis directions for providing at least one of dynamic motion compensation and off-central-axis radiation treatment. 
     
     
         23 . The method of  claim 20 , the IGRT apparatus further comprising an onboard imaging system comprising a kV imaging source and a kV imaging detector coupled to said gantry frame in outwardly movable manners by respective second and third arms extending outwardly from said gantry frame, wherein said operating the IGRT apparatus further comprises:
 operating the imaging system to acquire a plurality of intrafraction images of the body part during the treatment fraction; and   adjusting said operation of the articulated robot arm during the treatment fraction based at least in part on information derived from the intrafraction images.   
     
     
         24 . The method of  claim 23 , said ring member being a first ring member, said kV imaging source and kV imaging detector being a first kV source-detector pair, said second and third arm members being coupled to a second ring member included in the gantry frame and rotatable around said central axis independently of said first ring member, wherein said operating the imaging system comprises:
 operating said first kV source-detector pair to acquire a first intrafraction image with said second ring member at a first ring angle;   rotating said second ring member to a second ring angle that differs from said first ring angle; and   operating said first kV source-detector pair to acquire a second intrafraction image with said second ring member at said second ring angle.   
     
     
         25 . The method of  claim 24 , wherein said first and second ring angles differ by a stereoscopic imaging arc, wherein stereoscopic intrafraction imaging is performed using only a single kV source-detector pair. 
     
     
         26 . The method of  claim 24 , said first kV source-detector pair being coupled to external kV imaging driving circuitry through slip-ring electrical contacts included in said second ring member, wherein said operating the imaging system comprises:
 rotating said second ring member through a plurality of complete rotations in a common rotational direction around said central axis; and   operating said first kV source-detector pair through at least a portion of each said rotation to achieve at least one of intrafraction tomosynthesis imaging and intrafraction cone beam CT (CBCT) imaging.   
     
     
         27 . The method of  claim 23 , said kV imaging source and kV imaging detector being a first kV source-detector pair, said onboard imaging system further comprising a second kV imaging source-detector pair coupled to said gantry frame in an outwardly movable manner by fourth and fifth arm members, respectively, said ring member being a first ring member, the gantry frame further including a second ring member rotatable around said central axis independently of said first ring member, said second, third, fourth, and fifth arm members being coupled to said second ring member such that said first and second kV imaging source-detector pairs rotate independently of said radiation treatment head around said central axis, wherein said operating the imaging system comprises:
 operating said first and second kV source-detector pairs to acquire first stereoscopic intrafraction images with said second ring member at a first ring angle;   rotating said second ring member to a second ring angle that differs from said first ring angle; and   operating said first and second kV source-detector pairs to acquire second intrafraction images with said second ring member at said second ring angle.   
     
     
         28 . The method of  claim 27 , said first and second kV source-detector pairs being coupled to external kV imaging driving circuitry through slip-ring electrical contacts included in said second ring member, wherein said operating the imaging system comprises:
 rotating said second ring member through a plurality of complete rotations in a common rotational direction around said central axis; and   operating said first and second kV source-detector pairs through at least a portion of each said rotation to achieve at least one of stereoscopic intrafraction tomosynthesis imaging and stereoscopic intrafraction cone beam CT (CBCT) imaging.   
     
     
         29 . The method of  claim 18 , said ring member defining a central bore in the gantry frame sufficiently large to allow a patient to be passed therethrough, the IGRT apparatus further comprising a high resolution collimated CT imaging apparatus disposed adjacent to said gantry frame near said second end of said ring member, said CT imaging apparatus having a central axis of rotation coincident with said central axis of said ring member and forming a common central bore with said ring member, the method further comprising:
 prior to said positioning the patient into a treatment position, translating the patient through said common central bore while operating the CT imaging apparatus to acquire at least one high resolution three-dimensional CT image of the body part; and   using information derived from said at least one high resolution three-dimensional CT image in at least one of said positioning the patient into the treatment position and said applying non-coplanar radiation treatment to the body part.