REGISTRATION BETWEEN COORDINATE SYSTEMS FOR VISUALIZING A TOOL

• US 20170172457A1
• Filed: 12/22/2015
• Published: 06/22/2017
• Est. Priority Date: 12/22/2015
• Status: Active Grant

• Current Assignee: Biosense Webster Israel Ltd. (Johnson & Johnson)
• Original Assignee: Biosense Webster Israel Ltd. (Johnson & Johnson)
• Inventors: Ephrath, Yaron, Govari, Assaf
• Granted Patent: US 10,524,695 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 2018/00351 Heart
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• CPC Class Codes: A61B 2576/00 Medical imaging apparatus involving image processing or analysis A61B1/00009, A61B6/52 and A61B8/52 take precedence; image processing per se G06T; details of algorithms for analysing medical images G06T7/0012
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: A61B 5/061 Determining position of a probe within the body employing means separate from the probe, e.g. sensing internal probe position employing impedance electrodes on the surface of the body A61B1/00158 takes precedence
• CPC Class Codes: A61B 5/066 Superposing sensor position on an image of the patient, e.g. obtained by ultrasound or x-ray imaging
• CPC Class Codes: A61B 5/6852 Catheters
• CPC Class Codes: A61B 5/7425 Displaying combinations of multiple images regardless of image source, e.g. displaying a reference anatomical image with a live image geometric transforms for image registration G06T3/14; enhancement using image fusion G06T5/50; algorithms for registration of images G06T7/30
• CPC Class Codes: A61M 25/0127 Magnetic means; Magnetic markers

Abstract

While a catheter that includes (i) a catheter body, and (ii) a catheter shaft, which includes a sensor and which is disposed inside a lumen of the catheter body, is inside a body of a subject, a coordinate system of the sensor is registered with a coordinate system of an imaging system, using (a) a calibration image, acquired by the imaging system, that shows an indication of a distal end of the catheter body, and (b) a signal from the sensor, but not using any indication of the sensor shown in the calibration image. Using the registering, a visual output is generated. Other embodiments are also described.

Claims

1. A method, comprising:

while a catheter that includes (i) a catheter body, and (ii) a catheter shaft, which includes a sensor and which is disposed inside a lumen of the catheter body, is inside a body of a subject, registering a coordinate system of the sensor with a coordinate system of an imaging system, using (a) a calibration image, acquired by the imaging system, that shows an indication of a distal end of the catheter body, and (b) a signal from the sensor, but not using any indication of the sensor shown in the calibration image; and

using the registering, generating a visual output.

2. The method according to claim 1, wherein generating the visual output comprises superimposing a visual representation of the distal end of the catheter body on an image of a portion of the body of the subject.

3. The method according to claim 2, wherein the distal end of the catheter body includes one or more electrodes, and wherein the visual representation of the distal end of the catheter body includes a visual representation of the one or more electrodes.

4. The method according to claim 2, wherein superimposing the visual representation of the distal end of the catheter body on the image of the portion of the body of the subject comprises superimposing the visual representation of the distal end of the catheter body on the image of the portion of the body of the subject during an ablation of the portion of the body of the subject.

5. The method according to claim 1, wherein generating the visual output comprises displaying a map of a portion of the body of the subject.

6. The method according to claim 5, wherein the map includes an electroanatomical map of at least a portion of a heart of the subject.

7. The method according to claim 1, wherein the sensor is an electromagnetic sensor.

8. The method according to claim 1, wherein the calibration image is a magnetic resonance imaging (MRI) image.

9. The method according to claim 8, wherein the indication of the distal end of the catheter body includes a void in the MRI image that corresponds to the distal end of the catheter body.

10. The method according to claim 1, wherein registering the coordinate system of the sensor with the coordinate system of the imaging system comprises:

ascertaining a position and an orientation of the distal end of the catheter body with respect to the coordinate system of the imaging system, by identifying the indication of the distal end of the catheter body in the calibration image,

based on the signal from the sensor, ascertaining a position and an orientation of the sensor with respect to the coordinate system of the sensor, and

using (i) the ascertained position and orientation of the distal end of the catheter body with respect to the coordinate system of the imaging system, (ii) the ascertained position and orientation of the sensor with respect to the coordinate system of the sensor, and (iii) a known position and orientation of the distal end of the catheter body with respect to the sensor, registering the coordinate system of the sensor with the coordinate system of the imaging system.

11. Apparatus, comprising:

an electrical interface; and

a processor, configured to;

while a catheter that includes (i) a catheter body, and (ii) a catheter shaft, which includes a sensor and which is disposed inside a lumen of the catheter body, is inside a body of a subject, register a coordinate system of the sensor with a coordinate system of an imaging system, using (a) a calibration image, acquired by the imaging system, that shows an indication of a distal end of the catheter body, and (b) a signal from the sensor received via the electrical interface, but not using any indication of the sensor shown in the calibration image, and

using the registering, drive a display to generate a visual output.

12. The apparatus according to claim 11, wherein the processor is configured to drive the display to generate the visual output by driving the display to superimpose a visual representation of the distal end of the catheter body on an image of a portion of the body of the subject.

13. The apparatus according to claim 12, wherein the distal end of the catheter body includes one or more electrodes, and wherein the visual representation of the distal end of the catheter body includes a visual representation of the one or more electrodes.

14. The apparatus according to claim 11, wherein the processor is configured to drive the display to generate the visual output by driving the display to display a map of a portion of the body of the subject.

15. The apparatus according to claim 14, wherein the map includes an electroanatomical map of at least a portion of a heart of the subject.

16. The apparatus according to claim 11, wherein the sensor is an electromagnetic sensor.

17. The apparatus according to claim 11, wherein the calibration image is a magnetic resonance imaging (MRI) image.

18. The apparatus according to claim 11, wherein the indication of the distal end of the catheter body includes a void in the MRI image that corresponds to the distal end of the catheter body.

19. The apparatus according to claim 11, wherein the processor is configured to register the coordinate system of the sensor with the coordinate system of the imaging system by:

ascertaining a position and an orientation of the distal end of the catheter body with respect to the coordinate system of the imaging system, by identifying the indication of the distal end of the catheter body in the calibration image,

based on the signal from the sensor, ascertaining a position and an orientation of the sensor with respect to the coordinate system of the sensor, and

using (i) the ascertained position and orientation of the distal end of the catheter body with respect to the coordinate system of the imaging system, (ii) the ascertained position and orientation of the sensor with respect to the coordinate system of the sensor, and (iii) a known position and orientation of the distal end of the catheter body with respect to the sensor, registering the coordinate system of the sensor with the coordinate system of the imaging system.

20. A computer software product comprising a tangible non-transitory computer-readable medium in which program instructions are stored, which instructions, when read by a processor, cause the processor to:

while a catheter that includes (i) a catheter body, and (ii) a catheter shaft, which includes a sensor and which is disposed inside a lumen of the catheter body, is inside a body of a subject, register a coordinate system of the sensor with a coordinate system of an imaging system, using (a) a calibration image, acquired by the imaging system, that shows an indication of a distal end of the catheter body, and (b) a signal from the sensor, but not using any indication of the sensor shown in the calibration image, and

using the registering, drive a display to generate a visual output.