ULTRASOUND-IMAGE-GUIDE SYSTEM AND VOLUME-MOTION-BASE CALIBRATION METHOD

• US 20140100452A1
• Filed: 06/21/2012
• Published: 04/10/2014
• Est. Priority Date: 06/27/2011
• Status: Abandoned Application

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Hall, Christopher Stephen, Jain, Armeet Kumar, Stanton, Douglas Allen
• Application Number:
  US14/123,786
• Publication Number:
  US 20140100452A1
• Time in Patent Office: Days
• US Class Current: 600/424
• CPC Class Codes: A61B 8/0841 for locating instruments
• CPC Class Codes: A61B 8/0883 for diagnosis of the heart
• CPC Class Codes: A61B 8/4254 using sensors mounted on the probe
• CPC Class Codes: A61B 8/4455 Features of the external shape of the probe, e.g. ergonomic aspects
• CPC Class Codes: A61B 8/4477 using several separate ultrasound transducers or probes
• CPC Class Codes: A61B 8/486 involving arbitrary m-mode
• CPC Class Codes: A61B 8/5207 involving processing of raw data to produce diagnostic data, e.g. for generating an image reconstruction G06T11/00
• CPC Class Codes: A61B 8/5215 involving processing of medical diagnostic data
• CPC Class Codes: A61B 8/585 Automatic set-up of the device
• CPC Class Codes: G06T 2207/10136 3D ultrasound image
• CPC Class Codes: G06T 7/80 Analysis of captured images to determine intrinsic or extrinsic camera parameters, i.e. camera calibration
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems

Abstract

The present invention relates to an ultrasound-image-guided system and to a volume-motion-based calibration method for operating such system. The system comprises one or more ultrasound probes (20) operable to generate image volumes (13i, 13j) of an anatomical object (10). The system further comprises an adapter device (50) comprising at least one position sensor (30), the adapter device (50) being, for one use event, attachable to one of the ultrasound probes (20). The at least one position sensor (30) is at a variable position with respect to the one or more ultrasound probes (20) from one use event to another use event. The system further comprises a tracking device (51) operable to generate tracking data (32) representative of a tracking of the at least one position sensor (30) within a coordinate system (11), and ultrasound imaging device (21) operable to generate imaging data (22) of the anatomical object (10) based on the image volumes (13i, 13j). The system further comprises a computation device (40) operable to automatically self-calibrate, for each use event, the imaging data (22) with respect to the coordinate system (11) of the at least one position sensor (30) by calculating a calibration matrix (51) using an image based volume motion (VM IB) and a tracking based volume motion (VM TB). The image based volume motion (VM IB) representing an image motion of at least two image volumes (13i, 13j) derived from the imaging data (22). The tracking based volume motion (VM TB) representing a tracking motion of the image volumes (13i, 13j) derived from the tracking data (32).

Claims

1. An ultrasound-image-guided system, the system comprising:

one or more ultrasound probes (20) operable to generate image volumes (13i, 13j) of an anatomical object (10);

an adapter device (50) comprising at least one position sensor (30), the adapter device (50) being, for one use event, attachable to one of the ultrasound probes (20), wherein the at least one position sensor (30) is at a variable position with respect to the one or more ultrasound probes (20) from one use event to another use event;

a tracking device (51) operable to generate tracking data (32) representative of a tracking of the at least one position sensor (30) within a coordinate system (11);

an ultrasound imaging device (21) operable to generate imaging data (22) of the anatomical object (10) based on the image volumes (13i, 13j); and

a computation device (40) operable to automatically self-calibrate, for each use event, the imaging data (22) with respect to the coordinate system (11) of the at least one position sensor (30) by calculating a calibration matrix (51) using an image based volume motion (VM_IB) and a tracking based volume motion (VM_TB),

the image based volume motion (VM_IB) representing an image motion of at least two image volumes (13i, 13j) derived from the imaging data (22),

the tracking based volume motion (VM_TB) representing a tracking motion of the image volumes (13i, 13j) derived from the tracking data (32).

2. The system of claim 1, wherein the system is uncalibrated before the computation device (40) automatically self-calibrates the imaging data (22) with respect to the coordinate system (11) of the at least one position sensor (30).

3. The system of claim 1, wherein the adapter device (50) is reusable for a plurality of use events.

4. The system of claim 1, wherein the adapter device (50) is a hard shell having the least one position sensor (30) integrated therein or attached thereto.

5. The system of claim 4, wherein the hard shell is separated into at least two parts adapted to be clamped against each other.

6. The system of claim 1, wherein the adapter device (50) is an elastic tube.

7. The system of claim 6, wherein the elastic tube is heat shrunk over the ultrasound probe.

8. The system of claim 1, wherein the adapter device (50) is an inelastic pre-form tube.

9. The system of claim 8, wherein the pre-form tube has an internal adhesive layer.

10. The system of claim 1, wherein the image based volume motion (VM_IB) is computed as a function of an image location (VL_ii) of a first image volume (13i) within the coordinate system (11) relative to an image location (VL_ji) of a second image volume (13j) within the coordinate system (11) and/or wherein the tracking based volume motion (VM_TB) is computed as a function of a tracked location (VL_it) of a first image volume (13i) within the coordinate system (11) as represented by the tracking data (32) and a tracked location (VL_jt) of a second image volume (13j) within the coordinate system (11) as represented by the tracking data (32).

11. The system of claim 1, wherein the computation device (40) is operable to calculate the calibration matrix by solving a linear equation using the tracking based volume motion and the image based volume motion.

12. The system of claim 1, wherein the at least one position sensor (30) is an electromagnetic sensor and the tracking device (51) is an electromagnetic tracking device.

13. The system of claim 1, the computation device (40) further operable to execute a validation testing of the calibration matrix (51) derived from the automatic self-calibration, including a testing of an absolute differential between the image based volume motion (VM_IB) and the tracking based volume motion (VM_TB).

14. A volume-motion-based calibration method for operating an ultrasound-image-guided system, the system comprising one or more ultrasound probes (20) operable to generate image volumes (13i, 13j) of an anatomical object (10), and an adapter device (50) comprising at least one position sensor (30), the adapter device (50) being, for one use event, attachable to one of the ultrasound probes (20), wherein the at least one position sensor (30) is at a variable position with respect to the one or more ultrasound probes (20) from one use event to another use event, the method comprising the steps of:

a) generating tracking data (32) representative of a tracking of the at least one position sensor (30) within a coordinate system (11);

b) generating imaging data (22) of the anatomical object (10) based on the image volumes (13i, 13j); and

c) automatically self-calibrating, for each use event, the imaging data (22) with respect to the coordinate system (11) of the at least one position sensor (30) by calculating a calibration matrix (51) using an image based volume motion (VM_IB) and a tracking based volume motion (VM_TB),

the image based volume motion (VM_IB) representing an image motion of at least two image volumes (13i, 13j) within the coordinate system (11) derived from the imaging data (22),

the tracking based volume motion (VM_TB) representing a tracking motion of the image volumes (13i, 13j) within the coordinate system (11) derived from the tracking data (32).

15. Computer program comprising program code means for causing a computer to carry out the steps of the method as claimed in claim 14 when said computer program is carried out on the computer.