DC magnetic-based position and orientation monitoring system for tracking medical instruments

• US 20110082366A1
• Filed: 09/29/2010
• Published: 04/07/2011
• Est. Priority Date: 10/04/2005
• Status: Active Grant

• Current Assignee: Northern Digital Inc. (Roper Technologies, Inc.)
• Original Assignee: Ascension Technology Corporation (Roper Technologies, Inc.)
• Inventors: Scully, Jack T., Schneider, Mark R.
• Granted Patent: US 8,942,780 B2
• Time in Patent Office: Days
• US Class Current: 600/424
• 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

Abstract

Miniaturized, five and six degrees-of-freedom magnetic sensors, responsive to pulsed DC magnetic fields waveforms generated by multiple transmitter options, provide an improved and cost-effective means of guiding medical instruments to targets inside the human body. The end result is achieved by integrating DC tracking, 3D reconstructions of pre-acquired patient scans and imaging software into a system enabling a physician to internally guide an instrument with real-time 3D vision for diagnostic and interventional purposes. The integration allows physicians to navigate within the human body by following 3D sensor tip locations superimposed on anatomical images reconstructed into 3D volumetric computer models. Sensor data can also be integrated with real-time imaging modalities, such as endoscopes, for intrabody navigation of instruments with instantaneous feedback through critical anatomy to locate and remove tissue. To meet stringent medical requirements, the system generates and senses pulsed DC magnetic fields embodied in an assemblage of miniaturized, disposable and reposable sensors functional with both dipole and co-planar transmitters.

Claims

1. Apparatus for determining the position and orientation of one or more points on a medical instrument relative to a reference frame in at least five degrees of freedom, comprising:

a) a pulsed DC magnetic field transmitter, including at least one DC magnetic field generating element;

b) a signal generation module, connected to said at least one generating element, said signal generation module comprising a digital to analog converter and a signal processor connected thereto, said digital to analog converter converting a digital signal to an analog signal and providing said analog signal to said at least one generating element of said pulsed DC magnetic field transmitter;

c) a medical instrument including at least one pulsed DC magnetic field sensor, the sensor configured to be attached to said medical instrument by mounting the sensor on or in said medical instrument, said medical instrument configured to be located within a patient and said sensor not visible outside said patient;

d) a 3D guidance electronics unit connected to said sensor;

e) wherein said signal generation module is configured to produce one or more pulsed DC transmit signals whose pulse time is adjusted for optimal performance and is configured to provide said one or more transmit signals to said at least one generating element of said pulsed DC magnetic field transmitter, said 3D guidance electronics unit is configured to receive one or more detected signals from said sensor, wherein at least a portion of said one or more detected signals;

(1) corresponds to said one or more pulsed DC transmitted signals, (2) is used to determine position and orientation of said sensor in at least five degrees of freedom from strength of said one or more pulsed DC transmitted signals and at least a portion of said one or more detected signals, and (3) indicates the position and orientation of one or more points on said medical instrument;

f) an imaging modality, connected to an imaging computer, said imaging modality capturing a plurality of 2D or 3D images of an anatomical region of interest of the patient; and

said at least one pulsed DC magnetic field sensor connected to said imaging computer;

g) wherein said imaging computer in communication with said 3D guidance electronics unit is configured to perform an operation to register the plurality of 2D or 3D images of the patient'"'"'s anatomical region of interest with the said instrument within a patient;

said imaging computer is configured to perform further operation to superimpose a cursor or icon representing said instrument onto the plurality of 2D or 3D images of the patient'"'"'s anatomical region of interest;

said cursor or icon is configured to move on the plurality of 2D or 3D images of the patient'"'"'s anatomical region of interest as a function of movement of said instrument being within the patient; and

h) an imaging computer display configured to display the plurality of 2D or 3D images of the patient'"'"'s anatomical region of interest with the superimposed cursor or icon of the medical instrument in a way such that a physician can intuitively orient said instrument within the patient to the image seen on any number of computer displays.

2. A medical device comprising:

a) pulsed DC magnetic field sensor for detecting a plurality of pulsed DC magnetic fields, said pulsed DC magnetic field sensor is configured to be located within a patient and not visible outside said patient;

b) a medical instrument to which said pulsed DC magnetic field sensor is attached;

c) a 3D guidance electronics unit connected to said pulsed DC magnetic field sensor, and a pulsed DC magnetic field transmitter connected to said 3D guidance electronics unit, whereby said electronics unit provides signals to said pulsed DC magnetic field transmitter and wherein said transmitter transmits said signals to said pulsed DC magnetic field sensor;

d) an imaging computer with appropriate imaging software and memory and a display device, said imaging computer receiving signals resulting from pulsing of said magnetic fields;

e) wherein said 3D guidance electronics unit is configured to receive pulsed DC magnetic field sensing information from said pulsed DC magnetic field sensor;

f) wherein said 3D guidance electronics unit is configured to operate signal processing circuitry and software in association with said pulsed DC magnetic field sensing information to continuously track position and orientation of said pulsed DC magnetic field sensor within said patient in at least five degrees of freedom at one or more points on or within said medical instrument whose position and orientation is thus continuously tracked within said patient;

(g) an imaging modality, connected to the imaging computer, said imaging modality capturing a plurality of 2D or 3D images of an anatomical region of interest of the patient; and

said at least one pulsed DC magnetic field sensor connected to the imaging computer;

h) wherein said imaging computer in communication with said 3D guidance electronics unit is configured to perform an operation to register the plurality of 2D or 3D images of the patient'"'"'s anatomical region of interest with the said instrument within a patient;

said imaging computer is configured to perform further operation to superimpose a cursor or icon representing said instrument onto the plurality of 2D or 3D images of the patient'"'"'s anatomical region of interest;

said cursor or icon is configured to move on said image data as a function of movement of said instrument being within the patient; and

i) the display device is configured to display the plurality of 2D or 3D images of the patient'"'"'s anatomical region of interest with the superimposed cursor or icon of the medical instrument in a way such that a physician can intuitively orient said instrument within the patient to the image seen on any number of computer displays.

3. Apparatus for determining the position and orientation of one or more points on a medical instrument relative to a reference frame in at least five degrees of freedom, comprising:

a) a pulsed DC magnetic field transmitter, including at least one DC magnetic field generating element;

b) a signal generation module, connected to said at least one generating element, said signal generation module comprising a digital to analog converter and a signal processor connected thereto, said digital to analog converter converting a digital signal to an analog signal and providing said analog signal to said at least one generating element of said pulsed DC magnetic field transmitter;

c) a medical instrument including at least one pulsed DC magnetic field sensor, the sensor configured to be attached to said medical instrument by mounting the sensor on or in said medical instrument, said medical instrument configured to be located within a patient and said sensor not visible outside said patient;

d) a 3D guidance electronics unit connected to said sensor;

e) wherein said signal generation module is configured to produce one or more pulsed DC transmit signals whose pulse time is adjusted for optimal performance and is configured to provide said one or more transmit signals to said at least one generating element of said pulsed DC magnetic field transmitter, said 3D guidance electronics unit is configured to receive one or more detected signals from said sensor, wherein at least a portion of said one or more detected signals;

(1) corresponds to said one or more pulsed DC transmitted signals, (2) is used to determine position and orientation of said sensor in at least five degrees of freedom from strength of said one or more pulsed DC transmitted signals and at least a portion of said one or more detected signals, and (3) indicates the position and orientation of one or more points on said medical instrument;

f) an ultrasound detector, connected to an imaging computer, said ultrasound detector capturing a plurality of 2D or 3D ultrasound frames of an anatomical region of interest of the patient; and

said at least one pulsed DC magnetic field sensor connected to said imaging computer;

g) a position and orientation sensor that detects pulsed DC magnetic fields, mounted in or on the ultrasound detector to determine its 3D location, said position and orientation sensor detecting position and orientation of each of said plurality of 2D or 3D ultrasound frames of the patient'"'"'s anatomical region of interest;

h) wherein said imaging computer in communication with said 3D guidance electronics unit is configured to perform an operation to register said plurality of 2D or 3D ultrasound frames of the patient'"'"'s anatomical region of interest with the said instrument within a patient;

said imaging computer is configured to perform further operation to superimpose a cursor or icon representing said instrument onto said plurality of 2D or 3D ultrasound frames of the patient'"'"'s anatomical region of interest;

said cursor or icon is configured to move on said plurality of 2D or 3D ultrasound frames of the patient'"'"'s anatomical region of interest as a function of movement of said instrument being within the patient; and

is configured to construct an image from said plurality of 2D or 3D ultrasound frames of the patient'"'"'s anatomical region of interest and the detected position and orientation of each of said frames with respect to the detected position and orientation of one or more points on said medical instrument; and

i) an imaging computer display configured to display the plurality of 2D or 3D ultrasound frames of the patient'"'"'s anatomical region of interest with the superimposed cursor or icon of the medical instrument in a way such that a physician can intuitively orient said instrument within the patient to the image seen on any number of computer displays.