TRACKING SYSTEM AND METHOD

• US 20140330114A1
• Filed: 11/21/2012
• Published: 11/06/2014
• Est. Priority Date: 11/21/2011
• Status: Active Grant

• Current Assignee: Technische Universitat Munchen
• Original Assignee: Technische Universitat Munchen
• Inventors: Navab, Nassir
• Granted Patent: US 10,639,017 B2
• Time in Patent Office: Days
• US Class Current: 600/424
• CPC Class Codes: A61B 1/041 Capsule endoscopes for imaging
• CPC Class Codes: A61B 17/00234 for minimally invasive surgery A61B17/0218, A61B17/0469, A61B17/12013, A61B17/1285, A61B17/29, A61B17/320016 take precedence
• CPC Class Codes: A61B 2017/003 Steerable
• CPC Class Codes: A61B 2034/2057 Details of tracking cameras
• CPC Class Codes: A61B 2034/301 for introducing or steering flexible instruments inserted into the body, e.g. catheters or endoscopes
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 34/30 Surgical robots
• CPC Class Codes: A61B 5/0507 using microwaves or terahertz waves
• 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 5/062 using magnetic field
• CPC Class Codes: A61B 5/7405 using sound
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: A61B 5/7455 characterised by tactile indication, e.g. vibration or electrical stimulation
• CPC Class Codes: A61B 6/032 Transmission computed tomography [CT]
• CPC Class Codes: A61B 6/037 Emission tomography
• CPC Class Codes: A61B 8/0841 for locating instruments
• CPC Class Codes: G01B 11/002 for measuring two or more coordinates
• CPC Class Codes: G01B 15/00 Measuring arrangements characterised by the use of electromagnetic waves or particle radiation, e.g. by the use of microwaves, X-rays, gamma rays or electrons characterised by the use of optical techniques G01B9/00, G01B11/00
• CPC Class Codes: G01B 17/00 Measuring arrangements characterised by the use of infrasonic, sonic or ultrasonic vibrations
• CPC Class Codes: G01B 21/04 : by measuring coordinates of points
• CPC Class Codes: G01B 5/004 : for measuring coordinates of points
• CPC Class Codes: G01B 5/02 : for measuring length, width or thickness G01B5/004, G01B5/08 take precedence
• CPC Class Codes: G01B 5/18 : for measuring depth
• CPC Class Codes: G01B 7/003 : for measuring position, not involving coordinate determination coordinate measuring G01B7/004
• CPC Class Codes: G01D 5/125 : characterised by a first part whose movement represents the measuring value, and by a second part which is moved by an external force in order to follow the movement of the first part
• CPC Class Codes: G01S 5/18 : using ultrasonic, sonic, or infrasonic waves

Abstract

A system for tracking a tracking element inside a body is provided. It includes a first tracking system, which includes a first tracking sensor for detecting the current position of a tracking element inside a body relative to a nominal position with respect to the first tracking sensor, and a second tracking system, which includes a second tracking sensor for determining the position of the first tracking sensor of the first tracking system relative to the second tracking sensor, and a control unit. The first tracking sensor is movable, and the control unit is configured to deliver a correction signal indicating a deviation of the current position of the tracking element relative to a nominal position with reference to the first tracking sensor. Further, a respective tracking method is provided.

Claims

1. A system for tracking a tracking element inside a body, comprising:

a first tracking system, comprising;

a first tracking sensor for detecting the current position of a tracking element inside a body relative to a nominal position with respect to the first tracking sensor,

a second tracking system, comprising;

a second tracking sensor for determining the position of the first tracking sensor of the first tracking system relative to the second tracking sensor,

a control unit, wherein the first tracking sensor is movable, and wherein the control unit is configured to deliver a correction signal indicating a deviation of the current position of the tracking element relative to a nominal position with reference to the first tracking sensor.

2. The system of claim 1, further comprising:

a unit for the optic, acoustic, or haptic display of the correction signal to a user.

3. The system of claim 1, further comprising:

at least one actuator, which is controlled by the control unit to move the first tracking sensor in response to the correction signal, so that a relative position of the tracking element with respect to the tracking sensor is maintained within a predefined tolerance space.

4. The system according to claim 1, wherein the second tracking system comprises at least one of the following:

a mechanical arm, a robot arm, an optical tracking sensor, a radio frequency based tracking system, a robotic vehicle.

5. The system according to claim 1, wherein the first tracking sensor is at least one of a magnetic sensor, a detector for radioactive radiation, radio frequency, or for ultrasound, a PET detector, a SPECT detector, or a gamma camera.

6. The system according to claim 1, further comprising a patient bed with a laying surface for a patient, and wherein the first tracking sensor is located movable below the laying surface.

7. The system according to claim 6, wherein the first tracking sensor is movable by at least one belt.

8. A method for tracking the position of a tracking element inside a body, comprising:

positioning a tracking element inside a body;

positioning a first tracking sensor in the vicinity of the body, so that the sensor is able to detect the tracking element,

determining a first relative position of the tracking element with respect to the first tracking sensor, in a first coordinate system,

maintaining, within a predefined tolerance space, the first relative position between the tracking element and the first tracking sensor, when the tracking element changes its position relative to the body.

9. The method of claim 8, wherein maintaining the relative position comprises:

manually moving the first tracking sensor in response to a correction signal displayed to a user, or

moving the first tracking sensor via an actuator controlled by a control unit.

10. The method of claim 9, wherein the actuator moving the first tracking sensor comprises at least one of:

a robot arm, an automated vehicle, a belt, and a rail, both of the latter two below a laying surface of a patient bed, which actuator is controlled by a control unit.

11. The method of claim 8, wherein maintaining the relative position between the first tracking sensor and the tracking element comprises the case that a deviation of the current position from the first relative position is minimized, but not zero, if external factors prevent that the first relative position can be precisely maintained.

12. The method of claim 8, wherein a deviation signal carries information about a deviation in two spatial dimensions (x, y) or in three spatial dimensions (x, y, z), and information about a rate of change per time unit.

13. The method of claim 8, wherein the position of the body is determined in at least one of the first and second coordinate systems by tracking markers attached to the body.

14. The method of claim 13, wherein a position of the body is detected by an optical tracking system, which tracks markers on the body, in a third coordinate system.

15. The method of claim 14, further comprising:

correlating the body position with the position of the first tracking sensor,

calculating a position of the tracking element inside the body, and

displaying/visualizing the position of the tracking element in pre-operative or live images of the body acquired by X ray computed tomography.