Apparatus and method for generating a magnetic field

• US 20060114088A1
• Filed: 01/13/2006
• Published: 06/01/2006
• Est. Priority Date: 07/16/2002
• Status: Abandoned Application

• Current Assignee: Neuro-Kinesis Corporation
• Original Assignee: Neuro-Kinesis Corporation
• Inventors: Shachar, Yehoshua
• Application Number:
  US11/331,944
• Publication Number:
  US 20060114088A1
• Time in Patent Office: Days
• US Class Current: 335/219
• CPC Class Codes: A61B 17/22 Implements for squeezing-off ulcers or the like on the inside of inner organs of the body; Implements for scraping-out cavities of body organs, e.g. bones; Calculus removers; Calculus smashing apparatus; Apparatus for removing obstructions in blood vessels, not otherwise provided for dilators A61M29/00
• CPC Class Codes: A61B 2017/00084 Temperature
• CPC Class Codes: A61B 2017/003 Steerable
• CPC Class Codes: A61B 2017/00703 correcting for movement of heart, e.g. ECG-triggered
• CPC Class Codes: A61B 2034/102 Modelling of surgical devices, implants or prosthesis
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• 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 2034/732 arranged around the patient, e.g. in a gantry
• CPC Class Codes: A61B 2034/742 Joysticks
• CPC Class Codes: A61B 2090/365 augmented reality, i.e. correlating a live optical image with another image
• CPC Class Codes: A61B 2090/376 using X-rays, e.g. fluoroscopy
• CPC Class Codes: A61B 2090/3954 magnetic, e.g. NMR or MRI
• 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 34/70 Manipulators specially adapted for use in surgery
• CPC Class Codes: A61B 34/73 Manipulators for magnetic surgery
• CPC Class Codes: A61B 34/76 Manipulators having means for providing feel, e.g. force or tactile feedback
• CPC Class Codes: A61B 5/06 Devices, other than using radiation, for detecting or locating foreign bodies for removing same A61B17/50 ; determining position of probes within or on the body of the patient
• CPC Class Codes: A61B 5/062 using magnetic field
• CPC Class Codes: A61B 5/7455 characterised by tactile indication, e.g. vibration or electrical stimulation
• CPC Class Codes: A61M 25/0158 with magnetic or electrical means, e.g. by using piezo materials, electroactive polymers, magnetic materials or by heating of shape memory materials

Abstract

A system whereby a magnetic tip attached to a surgical tool is detected, displayed and influenced positionally so as to allow diagnostic and therapeutic procedures to be performed rapidly, accurately, simply, and intuitively is described. The tools that can be so equipped include catheters, guidewires, and secondary tools such as lasers and balloons, in addition biopsy needles, endoscopy probes, and similar devices. The magnetic tip allows the position and orientation of the tip to be determined without the use of x-rays by analyzing a magnetic field. The magnetic tip further allows the tool tip to be pulled, pushed, turned, and forcefully held in the desired position by applying an appropriate magnetic field external to the patient'"'"'s body. A Virtual Tip serves as an operator control. Movement of the operator control produces corresponding movement of the magnetic tip inside the patient'"'"'s body. Additionally, the control provides tactile feedback to the operator'"'"'s hand in the appropriate axis or axes if the magnetic tip encounters an obstacle. The output of the control combined with the magnetic tip position and orientation feedback allows a servo system to control the external magnetic field by pulse width modulating the positioning electromagnet. Data concerning the dynamic position of a moving body part such as a beating heart offsets the servo systems response in such a way that the magnetic tip, and hence the secondary tool is caused to move in unison with the moving body part. The tip position and orientation information and the dynamic body part position information are also utilized to provide a display that allows three dimensional viewing of the magnetic tip position and orientation relative to the body part.

Claims

1. An apparatus for generating a magnetic field, comprising;

a first cluster of first electromagnet poles provided to a mass of magnetic material;

a first plurality of electromagnet coils provided to said first electromagnet poles, said first plurality of electromagnet coils controllable on a substantially separate basis;

a second cluster of second electromagnet poles provided to said mass of magnetic material such that said second cluster of second electromagnet poles substantially opposes said first cluster of first electromagnet poles, said magnetic mass completing a magnetic circuit from said first cluster said second cluster; and

a second plurality of electromagnet coils provided to said second electromagnet poles, said second plurality of electromagnet coils controllable on a substantially separate basis such that an orientation of a magnetic field in a region between said first cluster and said second cluster is controllable in multiple dimensions.

2. The apparatus of claim 1, wherein said first cluster of first electromagnet poles comprises three electromagnet poles.

3. The apparatus of claim 1, wherein pole faces of said first electromagnet poles lie substantially on a sphere.

4. The apparatus of claim 1, wherein pole faces of said first electromagnet poles lie substantially on a sphere and where pole faces of said second electromagnet poles lie substantially on said sphere.

5. The apparatus of claim 1, further comprising a system controller to control electric currents in said first plurality of coils and said second plurality of coils to control said orientation of said magnetic field.

6. The apparatus of claim 1, further comprising:

a tool having a distal end responsive to said orientation of said magnetic field; and

one or more magnetic sensors to sense a magnetic field produced by said distal end.

7. The apparatus of claim 6, said distal end comprising one or more magnetic field sensors and one or more temperature sensors.

8. The apparatus of claim 6, further comprising a Virtual Tip control device to allow user control inputs.

9. The apparatus of claim 6, further comprising a Virtual Tip that provides tactile feedback to an operator.

10. The apparatus of claim 9, wherein said Virtual Tip provides tactile feedback to an operator according to a position error between an actual position of said distal end and a desired position of said distal end.

11. The apparatus of claim 6, further comprising a system controller to control electric currents in said first plurality of coils and said second plurality of coils to control said orientation of said magnetic field to apply magnetic force to said distal end.