Calibration of a rigid ENT tool

Patent metadata

Field	Value
Publication number	US-11065064-B2
Application number	US-201715812059-A
Country	US
Kind code	B2
Filing date	Nov 14, 2017
Priority date	Nov 14, 2017
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

An apparatus, including a magnetic field generator, a first magnetic field sensor configured for attachment to a proximal end of a surgical tool configured for insertion into a body, and a calibration device that includes a second magnetic field sensor and a proximity sensor, wherein the field sensors generate respective location signals responsive to a magnetic field emanating from the generator and traversing the field sensors. The apparatus includes a control unit, which receives the signals from all the sensors, extracts respective location and orientation coordinates of the field sensors based on the signals, computes a conversion relation between the coordinates of the first sensor and a distal end of the tool that is brought into contact with the calibration device, and subsequently applies the conversion relation, together with the coordinates of the first sensor, in providing a visual indication of a location of the distal end inside the body.

First claim

The invention claimed is:

1. An apparatus, comprising:
a magnetic field generator;
a first magnetic field sensor configured for attachment to a proximal end of a rigid surgical tool configured to be inserted into a living body, wherein the rigid surgical tool comprises a handle and an insertion tube, and wherein the first magnetic field sensor is configured to be coupled to the handle and the insertion tube and to be disposed coaxially with and between both the handle and the insertion tube when attached to the proximal end of the rigid surgical tool;
a calibration device, including a second magnetic field sensor and a proximity sensor, wherein the first and the second field sensors generate respective location signals responsive to a magnetic field emanating from the magnetic field generator and traversing the sensors, and wherein the proximity sensor generates a proximity signal indicating a contact with the calibration device; and
a control unit, which receives the signals from all the sensors, extracts respective location and orientation coordinates of the magnetic field sensors based on the signals, computes a conversion relation between the coordinates of the first magnetic field sensor and a distal end of the tool that is brought into contact with the calibration device, and subsequently applies the conversion relation, together with the coordinates of the first magnetic field sensor, in providing a visual indication of a location of the distal end of the tool inside the body.

2. The apparatus according to claim 1 , wherein the rigid surgical tool comprises a rigid endoscope.

3. The apparatus according to claim 1 , wherein the proximity sensor comprises a contact indicator.

4. The apparatus according to claim 3 , wherein the proximity sensor is selected from a group consisting of a force sensor, an optical sensor and an electrical sensor.

5. The apparatus according to claim 1 , wherein the first magnetic field sensor is configured to be removably attached to the proximal end of the rigid surgical tool.

6. The apparatus according to claim 1 , and comprising a display configured to present the visual indication of the location of the distal end of the tool inside the body.

7. The apparatus according to claim 1 , and comprising a memory, wherein the control unit is configured to store the computed conversion relation to the memory, and to retrieve the conversion relation from the memory.

8. The apparatus according to claim 1 , wherein the conversion relation comprises an orientation and a distance between the location of the first magnetic field sensor and a location of the distal end.

9. The apparatus according to claim 1 , wherein the magnetic field sensor is contained within a removable fixture having a proximal end connected to a distal end of the handle and a distal end connected to a proximal end of the insertion tube.

10. A method, comprising:
receiving, from a first magnetic field sensor attached to a proximal end of, and longitudinally interposed between a distal end of a handle and a proximal end of an insertion tube of, a rigid surgical tool, first location signals responsive to a magnetic field emanating from a magnetic field generator and traversing the first magnetic field sensor;
placing a calibration device comprising a second magnetic field sensor on a reference object in the magnetic field emanating from the magnetic field generator, wherein the magnetic field generator is disposed below the reference object;
receiving, from the second magnetic field sensor in the calibration device, second location signals responsive to the magnetic field emanating from the magnetic field generator and traversing the second magnetic field sensor;
receiving, from a proximity sensor in the calibration device, a proximity signal indicating a contact with the calibration device;
extracting, by a processor, respective location and orientation coordinates of the magnetic field sensors based on the signals;
computing a conversion relation between the coordinates of the first magnetic field sensor and a distal end of the tool that is brought into contact with the calibration device; and
subsequently applying the conversion relation, together with the coordinates of the first magnetic field sensor, in providing a visual indication of a location of the distal end of the tool inserted into a living body.

11. The method according to claim 10 , wherein the rigid surgical tool comprises a rigid endoscope.

12. The method according to claim 10 , wherein the proximity sensor comprises a contact indicator.

13. The method according to claim 12 , wherein the proximity sensor is selected from a group consisting of a force sensor, an optical sensor and an electrical sensor.

14. The method according to claim 10 , wherein the first magnetic field sensor is removably attached to the proximal end of the rigid surgical tool.

15. The method according to claim 10 , wherein the reference object comprises a surface of the living body.

16. The method according to claim 10 , wherein presenting the visual indication, comprises presenting, on a display, the location of the distal end of the tool inside the body.

17. The method according to claim 10 , and comprising storing the computed conversion relation to a memory, and subsequently retrieving the conversion relation from the memory.

18. The method according to claim 10 , wherein the conversion relation comprises an orientation and a distance between the location of the first magnetic field sensor and a location of the distal end.

19. The method according to claim 10 , wherein the magnetic field generator is disposed below an operating table.

20. An apparatus, comprising:
a magnetic field generator;
a first magnetic field sensor attached a proximal end of a rigid surgical tool configured to be inserted into a living body, wherein the rigid surgical tool comprises a handle and an insertion tube;
a calibration device, including a second magnetic field sensor and a proximity sensor, wherein the first and the second field sensors generate respective location signals responsive to a magnetic field emanating from the magnetic field generator and traversing the sensors, and wherein the proximity sensor generates a proximity signal indicating a contact with the calibration device; and
a control unit, which receives the signals from all the sensors, extracts respective location and orientation coordinates of the magnetic field sensors based on the signals, computes a conversion relation between the coordinates of the first magnetic field sensor and a distal end of the tool that is brought into contact with the calibration device, and subsequently applies the conversion relation, together with the coordinates of the first magnetic field sensor, in providing a visual indication of a location of the distal end of the tool inside the body;
wherein the insertion tube has a proximal end positioned at a distal end of the first magnetic field sensor and the handle has a distal end positioned at a proximal end of the first magnetic field sensor.

Assignees

• Biosense Webster Israel Ltd

Inventors

• Pinsky Yoav
• Zoabi Akram
• Bustan Itamar
• Alroy Levy Michal

Classifications

• A61B1/00057 Primary

  provided with means for testing or calibration · CPC title

• A61B2560/0223

  of calibration, e.g. protocols for calibrating sensors · CPC title

• A61B2090/0811

  for the position of a particular part of an instrument with respect to the rest of the instrument, e.g. position of the anvil of a stapling instrument · CPC title

• A61B2090/065

  for measuring contact or contact pressure · CPC title

• A61B2034/2055

  Optical tracking systems · CPC title