Virtually-oriented electromagnetic tracking coil for catheter based navigation

Patent metadata

Field	Value
Publication number	US-10966629-B2
Application number	US-201515529766-A
Country	US
Kind code	B2
Filing date	Nov 12, 2015
Priority date	Dec 1, 2014
Publication date	Apr 6, 2021
Grant date	Apr 6, 2021

Abstract

A system and medical device for the electromagnetic tracking of a medical instrument transported through the medical device. The medical device has a central axis and a channel that receives and transports a medical instrument through the medical device. The channel extends to a distal portion of the medical device and connects with an opening in the medical device that is not aligned with the central axis. The medical device includes a tracking component that is a plurality of coordinated electromagnetic sensors for generating a virtual axis of travel for the medical instrument, with the virtual axis passing through the opening of the device and being aligned with tool insertion axis.

First claim

The invention claimed is:

1. A medical device for tracking a medical instrument comprising:
a channel for receiving and transporting the medical instrument through the medical device, the channel extending to a distal portion of the medical device and connecting with an opening in the medical device that is not aligned with a central axis of the medical device and that is aligned with a tool insertion axis; and
a tracking component comprising a plurality of coordinated electromagnetic sensors, said plurality of coordinated electromagnetic sensors generating a virtual axis of travel for the medical instrument, wherein the virtual axis passes through the opening of the medical device and the virtual axis is aligned with the tool insertion axis, wherein the virtual axis corresponds to a vector-sum of individual sensitivities of the plurality of coordinated electromagnetic sensors,
wherein the plurality of coordinated electromagnetic sensors comprises a first coil and a second coil of an electromagnetic material, the first coil being in concentric arrangement with the central axis of the medical device, the second coil being in orthogonal arrangement to the first coil,
wherein the medical instrument is tracked by applying an alternating current to the first and second coils to generate a time-varying magnetic field extending along and aligned with the tool insertion axis, whereby an electromotive force is induced in a pickup coil arranged on the medical instrument by the time-varying magnetic field enabling the tracking of the medical instrument along the generated virtual axis.

2. The medical device of claim 1 , wherein at least one of the first coil and the second coil is cylindrically symmetrical.

3. The medical device of claim 1 , wherein the first coil and the second coil are cylindrically symmetrical.

4. The medical device of claim 1 , wherein the first coil and the second coil are comprised of loops of wire windings, the loops of at least one of the first coil and the second coil defining an area that is substantially perpendicular to a lengthwise axis that passes through the at least one of the first coil and the second coil.

5. The medical device of claim 1 , wherein the first coil and the second coil are comprised of loops of wire windings, the loops of the first coil and the loops of the second coil define respective areas that are substantially perpendicular to respective lengthwise axes that pass through the first coil and the second coil, respectively.

6. The medical device of claim 1 , wherein the first coil and the second coil are comprised of loops of wire windings of, respectively, N1 and N2 turns, where N is number of turns,
the first coil and the second coil having, respectively, A1 and A2 cross sectional areas, wherein the first coil has a coil sensitivity value of S1 being the multiplication product of N1 and A1, and the second coil has a coil sensitivity value of S2 being the multiplication product of N2 and A2, and wherein N1>N2.

7. The medical device of claim 1 , wherein the first coil is concentric to the channel and the second coil is positioned to a side of the channel.

8. The medical device of claim 1 , wherein the first coil and the second coil are electrically connected in series.

9. A method for tracking a medical instrument coupled to a medical device comprising:
inserting a medical device into a body of a patient, the medical device comprising a channel for receiving and transporting a medical instrument for conducting a medical procedure through the medical device, the channel extending to a distal portion of the medical device and connecting with an opening in the medical device that is not aligned with a central axis of the medical device and that is aligned with a tool insertion axis, the medical device further comprising a tracking component that includes a plurality of coordinated electromagnetic sensors generating a virtual axis of travel for a medical instrument, wherein the virtual axis passes through the channel and the opening of the medical device and the virtual axis is aligned with a tool insertion axis, wherein the plurality of coordinated electromagnetic sensors comprises a first coil and a second coil of an electromagnetic material, the first coil being in concentric arrangement with the central axis of the medical device, the second coil being in orthogonal arrangement to the first coil;
analyzing information obtained from the tracking component, whereby a virtual axis passing through the medical device opening is obtained, and placing the virtual axis into a position and alignment suited for conducting the medical procedure, wherein the medical instrument is tracked by applying an alternating current to the plurality of coordinated electromagnetic sensors to generate a time-varying magnetic field extending along and aligned with the tool insertion axis, whereby an electromotive force is induced in a pickup coil arranged on the medical instrument by the time-varying magnetic field enabling the tracking of the medical instrument along the generated virtual axis;
transporting the medical instrument for conducting the medical procedure through the channel of the medical device to the site of the medical procedure;
tracking the medical instrument and directing the medical instrument through the opening in the medical device that is along the virtual axis and conducting the medical procedure;
retrieving the medical instrument; and
removing the medical device from the patient's body.

10. The method of claim 9 , further comprising generating a current in at least one of the plurality of coordinated electromagnetic sensors and analyzing information through synchronous detection to resolve a measured signal against the generated current, whereby information concerning a geometrical relation between coordinated electromagnetic sensors is obtained.

11. The method of claim 9 , wherein the medical device is one of a bronchoscope, a catheter, a guidewire, a probe, an endoscope, a prostate intervention device, an endoscopic retrograde cholangiopancreatography device, and an electromagnetically-tracked robotic device.

12. The method of claim 9 , wherein the medical procedure is a biopsy.

13. The method of claim 12 , wherein the biopsy is conducted at a site that is outside of a body passageway.

Assignees

• Koninklijke Philips Nv

Inventors

• Mehendale Aditya
• Sahin Funda
• Cole Gregory
• Su Hao
• Parthasarathy Vijay

Classifications

• A61B34/20

  Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis · CPC title

• A61B2034/2061

  using shape-sensors, e.g. fiber shape sensors with Bragg gratings · CPC title

• A61B17/00234

  for minimally invasive surgery (A61B17/0218, A61B17/0469, A61B17/12013, A61B17/1285, A61B17/29, A61B17/320016 take precedence) · CPC title

• A61B2034/2051

  Electromagnetic tracking systems · CPC title

• A61M25/09

  Guide wires · CPC title