Systems and methods for using x-ray field emission to determine instrument position and orientation

Abstract

A device is provided that comprises: a flexible body; a position sensor located at the flexible body; and a field emission x-ray device located at the flexible body.

What is claimed is: 
     
         1 . A device comprising:
 a flexible body;   a position sensor located at the flexible body; and   a field emission x-ray device located at the flexible body.   
     
     
         2 . The device of  claim 1 , wherein the flexible body includes a distal end portion and a proximal end portion, and further including:
 multiple field emission x-ray devices located at the distal end portion.   
     
     
         3 . The device of  claim 1 , wherein the flexible body includes a distal end portion and a proximal end portion, and further including:
 multiple field emission x-ray devices located at the distal end portion,   wherein the distal end portion includes a circumference, and   wherein the multiple field emission x-ray devices are disposed angularly displaced about the circumference of the distal end portion.   
     
     
         4 . The device of  claim 1 , wherein the flexible body includes a distal end portion and a proximal end portion, and further including:
 multiple field emission x-ray devices located at the distal end portion,   wherein the multiple field emission x-ray devices are configured to emit x-rays on adjacent paths.   
     
     
         5 . The device of  claim 1 , wherein the flexible body includes a distal end portion and a proximal end portion, and further including:
 multiple field emission x-ray devices located at the distal end portion,   wherein the multiple field emission x-ray devices are configured to emit x-rays on parallel paths.   
     
     
         6 . The device of  claim 1 , wherein the flexible body includes a distal end portion and a proximal end portion, and further including:
 multiple field emission x-ray devices located at the distal end portion; and   an effector located at the distal end portion,   wherein the multiple field emission x-ray devices are configured to emit x-rays on paths incident upon a working volume located within a human body.   
     
     
         7 . The device of  claim 1 , wherein the flexible body includes a distal end portion and a proximal end portion, and further including:
 multiple field emission x-ray devices located at the distal end portion; and   an effector located at the distal end portion,   wherein the multiple field emission x-ray devices are configured to emit x-rays on paths that are incident upon a volume that is displaced from a working volume located within a human body.   
     
     
         8 . The device of  claim 1 , wherein the flexible body includes a distal end portion and a proximal end portion, wherein the distal end portion is sized and shaped to be inserted within a human body, and wherein the field emission x-ray device is located at the distal end portion; and further including:
 a communications interface located at the proximal end portion.   
     
     
         9 . The device of  claim 1 , wherein the field emission x-ray device includes a carbon nanotube. 
     
     
         10 . The device of  claim 1 , wherein the position sensor includes an electromagnetic (EM) sensor. 
     
     
         11 . The device of  claim 1 , wherein the position sensor includes a shape sensor. 
     
     
         12 . The device of  claim 1 , wherein the position sensor includes an image capture element. 
     
     
         13 . The device of  claim 1 , wherein the flexible body includes a distal end portion and a proximal end portion, and wherein the field emission x-ray device is located at the distal end portion, and further including:
 a communications interface located at the proximal end portion; and   steering controls that are housed within the flexible body and that extend between the communications interface and the distal end portion.   
     
     
         14 . The device of  claim 1 , further including steering controls that include cables. 
     
     
         15 . The device of  claim 1 , wherein the flexible body includes a plurality of segments. 
     
     
         16 . The device of  claim 1 , wherein the flexible body defines at least one internal lumen. 
     
     
         17 . A system comprising:
 a flexible body sized and shaped to be inserted within a human body;   a detector configured to capture one or more x-ray images produced using a field emission x-ray device; and   one or more processors configured to determine similarity between the captured one or more x-ray images and a reference image.   
     
     
         18 . The system of  claim 17 , further comprising:
 a position sensor located at the flexible body; and   wherein the one or more processors are configured to:
 use the position sensor to sense a pose of the flexible body; 
 determine an estimated detected pose of the flexible body as a function of a determined similarity between the captured one or more x-ray images and a reference image; 
 determine an estimated offset between the sensed pose and the estimated detected pose; and 
 change a pose of a distal end portion of the flexible body as a function of the determined estimated offset. 
   
     
     
         19 . The system of  claim 18 , wherein sensing a pose of the distal end portion of the flexible body includes shape sensing. 
     
     
         20 . The system of  claim 18 , wherein sensing a pose of the distal end portion of the flexible body includes electromagnetic sensing. 
     
     
         21 . The system of  claim 17 , wherein the one or more processors are configured to convert the one or more captured x-ray images to at least one tomosynthesis image and wherein determining similarity includes searching for similarity between the at least one tomosynthesis image and a reference image. 
     
     
         22 . A method comprising:
 locating a field emission x-ray device at a distal end portion of a flexible body;   inserting the flexible body and the field emission x-ray device into an anatomical cavity within a patient's anatomy;   emitting x-ray radiation from the x-ray device; and   detecting the x-ray radiation emitted at a location outside the anatomical cavity.   
     
     
         23 . The method of  claim 22 , wherein inserting includes inserting into a body organ. 
     
     
         24 . The method of  claim 22 , wherein the anatomical cavity includes a natural lung passage. 
     
     
         25 . The method of  claim 22 , wherein the anatomical cavity includes a natural heart passage. 
     
     
         26 . The method of  claim 22 , wherein the anatomical cavity includes a natural digestive system passage. 
     
     
         27 . The method of  claim 22 , wherein detecting the emitted x-ray radiation includes capturing an x-ray image that includes an x-ray attenuation pattern indicative of anatomical structures traversed by the x-ray radiation, and further including:
 determining a similarity between the captured x-ray image and a reference image obtained from a three-dimensional (3-D) reference image of a portion of the patient's anatomy that includes the anatomical cavity.   
     
     
         28 . The method of  claim 27 , further including:
 sensing a pose of a distal end portion of the flexible body;   determining an estimated detected pose of the distal end portion as a function of the determined similarity of the reference image;   determining an estimated offset between the sensed pose and the estimated detected pose; and   changing the pose of the distal end portion as a function of the determined offset.   
     
     
         29 . The method of  claim 28 , wherein sensing the pose of the distal end portion of the flexible body includes shape sensing. 
     
     
         30 . The method of  claim 28 , wherein sensing the pose of the distal end portion of the flexible body includes electromagnetic sensing. 
     
     
         31 . The method of  claim 28 , wherein sensing includes sensing a pose of the distal end portion of the flexible body. 
     
     
         32 . The method of  claim 27 , wherein determining the similarity includes comparing captured x-ray image information with information for multiple different reference images obtained from the three-dimensional (3-D) reference image. 
     
     
         33 . The method of  claim 27 , wherein determining the similarity includes comparing a visual display representing captured x-ray images with visual displays for multiple different reference images obtained from the three-dimensional (3-D) reference image. 
     
     
         34 . The method of  claim 22 , further comprising:
 wherein detecting the emitted x-ray radiation includes capturing multiple x-ray images that include x-ray attenuation patterns indicative of anatomical structures traversed by the x-ray radiation;   converting the multiple x-ray images to at least one tomosynthesis image;   determining a similarity between the at least one tomosynthesis image and a reference image obtained from a three-dimensional (3-D) reference image of a portion of a patient's body that includes the anatomical cavity.   
     
     
         35 . The method of  claim 34  further including:
 sensing a pose of the distal end portion of the flexible body; 
 determining an estimated detected pose of the distal end portion as a function of the determined similarity of the reference image; 
 determining an estimated offset between the sensed pose and the detected pose; and 
 changing the pose of the distal end portion as a function of the determined offset. 
 
     
     
         36 . The method of  claim 35 , wherein sensing the pose of the distal end portion of the flexible body includes shape sensing. 
     
     
         37 . The method of  claim 35 , wherein sensing the pose of the distal end portion of the flexible body includes electromagnetic sensing. 
     
     
         38 . The method of  claim 35 , wherein sensing includes sensing a pose of the distal end portion of the flexible body. 
     
     
         39 . The method of  claim 35 , further including comparing tomosynthesis image information with information for multiple different reference images obtained from the three-dimensional (3-D) reference image to determine a match. 
     
     
         40 . The method of  claim 34 , further including comparing a visual display representing tomosynthesis image information with visual displays for multiple different reference images obtained from the three-dimensional (3-D) reference image to determine a match. 
     
     
         41 . A system comprising:
 a flexible body;   a field emission x-ray device located at the flexible body;   a detector configured to capture one or more x-ray images produced by the field emission x-ray device; and   one or more processors configured to:
 sense a pose of a distal end of the flexible body; 
 select a predicted reference image, as a function of the sensed pose, from a three-dimensional (3-D) reference image; and 
 search for similarity between the captured one or more x-ray images and a reference image obtained from a prescribed region of the three-dimensional (3-D) reference image about the predicted reference image. 
   
     
     
         42 . The system of  claim 41 , wherein the one or more processors are configured to convert the one or more captured x-ray images to at least one tomosynthesis image, and wherein searching for similarity includes searching for similarity between the at least one tomosynthesis image and a reference image. 
     
     
         43 . A system comprising:
 a flexible body;   a field emission x-ray device located at the flexible body;   a position sensor located at the flexible body;   a detector configured to detect one or more x-ray images produced using the field emission x-ray device; and   one or more processors configured to:
 use the position sensor to sense a pose of the flexible body; 
 select a predicted reference image, as a function of the sensed pose, from a three-dimensional (3-D) reference image; 
 search for a match between the detected one or more x-ray images and a reference image obtained from a prescribed region of the three-dimensional (3-D) reference image about the predicted reference image; 
 determine an estimated detected pose of the flexible body as a function of a determined match between the one or more detected x-ray images and a reference image; 
 determine an estimated offset between the sensed pose and the detected pose; and 
 change the pose of the flexible body as a function of the determined offset. 
   
     
     
         44 . A method comprising:
 providing a field emission x-ray device at a distal end portion of a flexible body;   inserting the flexible body and the field emission x-ray device into an anatomical cavity within a patient's body;   emitting x-ray radiation from the x-ray device;   capturing an x-ray image that includes an x-ray attenuation pattern indicative of anatomical structures traversed by the x-ray radiation;   sensing a pose of the distal end portion of the flexible body;   selecting a predicted reference image, as a function of the sensed pose, from a three-dimensional (3-D) reference image of a portion of a patient's anatomy that includes the anatomical cavity; and   searching for similarity between the captured x-ray image and a reference image obtained from a prescribed region of the three-dimensional (3-D) reference image about the predicted reference image.   
     
     
         45 . The method of  claim 44 , wherein capturing the x-ray image includes capturing multiple x-ray images; and
 wherein searching for similarity includes converting the multiple captured x-ray images to at least one tomosynthesis image and searching for similarity between the at least one tomosynthesis image and a reference image obtained from a prescribed region of the three-dimensional (3-D) reference image about the predicted reference image.   
     
     
         46 . A method comprising:
 inserting a flexible body that includes a position sensor and a field emission x-ray device into a human body cavity;   detecting one or more x-ray images emitted from the field emission x-ray device;   using the position sensor to sense a pose of the flexible body;   selecting a predicted reference image, as a function of the sensed pose, from a three-dimensional (3-D) reference image;   searching for a match between the one or more detected x-ray images and a reference image obtained from a prescribed region of the three-dimensional (3-D) reference image about the predicted reference image;   determining an estimated detected pose of the flexible body as a function of a determined match between the one or more detected x-ray images and a reference image;   determining an estimated offset between the sensed pose and the estimated detected pose; and   changing the pose of the flexible body as a function of the determined estimated offset.