Apparatus and method for 4d x-ray imaging

Patent metadata

Field	Value
Publication number	US-2018070902-A1
Application number	US-201715611900-A
Country	US
Kind code	A1
Filing date	Jun 2, 2017
Priority date	Sep 14, 2016
Publication date	Mar 15, 2018
Grant date	—

Abstract

A system for reconstructing a 4D image has a surface acquisition system for generating a 3D surface model of an object and an X-ray imaging system for acquiring at least one 2D X-ray projection image of the object. A controller controls the surface acquisition system and the X-ray imaging system. A processor applies a 4D reconstruction algorithm/method to the 3D surface model and the at least one 2D X-ray projection to reconstruct a 4D X-ray volume of the imaged body part in motion.

First claim

What is claimed is:

1 . A system for reconstructing a 4D image, comprising:
a surface acquisition system for generating a 3D surface model of an object; an X-ray imaging system for acquiring at least one 2D X-ray projection image of the object; a controller to control the surface acquisition system and the X-ray imaging system; and a processor to apply a 4D reconstruction algorithm/method to the 3D surface model and the at least one 2D X-ray projection to reconstruct a 4D X-ray volume of the imaged body part in motion.

2 . The system of claim 1 , wherein the surface acquisition system comprises:
one or more light sources adapted to project a known pattern of light grid onto the object; one or more optical sensors adapted to capture a plurality of 2D digital images of the object; and a surface reconstruction algorithm for reconstructing the 3D surface model of the object using the at least one 2D projection image.

3 . The system of claim 2 , wherein the light sources and the optical sensors are adapted to be either:
(i) mounted to a rotational gantry of the X-ray imaging system, (ii) affixed to the bore of the X-ray imaging system, or (iii) placed outside of (separate from) the X-ray imaging system.

4 . The system of claim 1 , wherein the X-ray imaging system comprises:
one or more X-ray sources adapted to controllably emit X-rays; and one or more X-ray detectors including a plurality of X-ray sensors adapted to detect X-rays that are emitted from the X-ray sources and have traversed the object.

5 . The system of claim 4 , wherein the X-ray sources and X-ray detectors move in a trajectory, wherein the trajectory includes, but is not limited to, a helix, full circle, incomplete circle, line, sinusoid, and stationary.

6 . The system of claim 1 , wherein the controller synchronizes the surface imaging system and the X-ray imaging system.

7 . The system of claim 1 , wherein the 4D reconstruction algorithm/method comprises:
an X-ray projection correction process to generate a corrected 2D X-ray projection; a 3D surface deformation process to deform each 3D surface model to the next time-adjacent 3D surface model and generate at least one transformation parameter; a 3D volume deformation process to deform the volume under reconstruction according to the at least one transformation parameter; a 3D volume deformation process to deform the volume under reconstruction according to the 2D X-ray projection using an anatomical structure or implant; and an analytical form reconstruction process or an iterative form reconstruction process.

8 . The system of 7 , wherein the X-ray projection correction process includes a scatter correction, a beam hardening correction, or a metal artifact reduction correction.

9 . The system of claim 7 , further comprising a 3D surface registration algorithm comprising a rigid-object registration algorithm or a deformable registration algorithm.

10 . The system of claim 7 , wherein the analytical form reconstruction process includes an FDK (Feldkamp-Davis-Kress) algorithm.

11 . The system of claim 7 , wherein the iterative form reconstruction process includes a SART algorithm, a statistical reconstruction algorithm, a total variation reconstruction algorithm, or an iterative FDK algorithm.

12 . The system of claim 7 , wherein the 4D reconstruction method is applied until a predetermined threshold criterion is met.

13 . A method comprising:
a) acquiring one or more radiographic images of patient anatomy at a first position; b) acquiring a first surface contour image of the patient anatomy at the first position; c) acquiring a second surface contour image of the patient anatomy after patient movement to a second position; d) continuously acquiring additional radiographic images of the patient anatomy after patient movement from the first to the second position; e) generating one or more transformed volume images of the patient anatomy according to the additionally acquired surface contour and radiographic images; and f) displaying, storing, or transmitting one or more portions of the one or more transformed volume images.

14 . The method of claim 13 wherein generating the one or more transformed volume images comprises comparing a computed forward projection image with an acquired radiographic image.

15 . The method of claim 13 wherein acquiring the radiographic images comprises acquiring the images using a cone-beam computed tomography system.

16 . The method of claim 13 wherein acquiring the first surface contour image comprises acquiring at least one structured light image.

17 . The method of claim 17 wherein displaying at least the transformed volume comprises displaying a motion picture image series showing portions of the generated transformed volume images.

18 . The method of claim 13 wherein generating the transformed volume image comprises using at least one of rigid transformation, non-rigid transformation, 3D-to-3D transformation, surface-based transformation, 3D-to-2D registration, feature-based registration, projection-based registration, and appearance-based transformation.

19 . The method of claim 13 wherein generating the one or more transformed volume images comprises using a reconstruction algorithm taken from the list consisting of a simultaneous algebraic reconstruction technique algorithm, a statistical reconstruction algorithm, a total variation reconstruction algorithm, and an iterative FDK algorithm.

20 . A method comprising:
a) acquiring one or more radiographic images of patient anatomy at a first position; b) acquiring a first surface contour image of the patient anatomy at the first position; c) acquiring a second surface contour image of the patient anatomy during patient movement to a second position; d) continuously acquiring additional radiographic images of the patient anatomy during patient movement from the first to the second position; e) generating a volume image of the patient and one or more transformed volume images of the patient anatomy according to the acquired surface contour and radiographic images; and f) displaying, storing, or transmitting portions of the one or more transformed volume images.

21 . The method of claim 20 further comprising acquiring a volume image of patient anatomy at a first position in the movement sequence.

22 . The method of claim 20 further comprising
(i) calculating a forward projection image of the transformed volume image at the second position;
(ii) comparing the calculated forward projection image with the acquired 2D radiographic projection at the second position; and
(iii) reconstructing the transformed volume image corresponding to the second position to form an updated volume image according to the comparison from step (ii).

23 . The method of claim 22 wherein reconstructing uses an algorithm taken from the list comprising a simultaneous algebraic reconstruction technique algorithm, a statistical reconstruction algorithm, a total variation reconstruction algorithm, and an iterative FDK algorithm.

Assignees

• Carestream Health Inc

Inventors

• Lin Yuan
• Sehnert William J

Classifications

• G06T12/20

  Inverse problem, i.e. transformations from projection space into object space · CPC title

• A61B5/1077

  Measuring of profiles · CPC title

• A61B6/5205

  involving processing of raw data to produce diagnostic data · CPC title

• A61B6/03

  Computed tomography [CT] · CPC title

• A61B5/0077

  Devices for viewing the surface of the body, e.g. camera, magnifying lens · CPC title