LOCATING A MEMBER IN A STRUCTURE

• US 20090264750A1
• Filed: 04/15/2009
• Published: 10/22/2009
• Est. Priority Date: 04/18/2008
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc), Regents of The University of Minnesota (University of Minnesota)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Giese, Chad, Receveur, Rogier, Phillips, Lane A., Markowitz, H. Toby, Falkner, Phillip, Warman, Eduardo N., Karamanoglu, Mustafa, Waldhauser, Steven L., Zhang, Shangqian Peter, Larik, Vincent, Michels, Koen, Eick, Olaf, Craig, Brian Houston, Scanlon, David A., Interrante, Victoria, Kryger, Michael, Campbell-Massa, Sean, Smith, Marie P., Fleming, Ioana, Hurtig, Noelle Christine, Chelgren, Brent, Mehta, Pooja, Nowak, Karl Evan, Steeves, James
• Granted Patent: US 8,424,536 B2
• Time in Patent Office: Days
• US Class Current: 600/424
• CPC Class Codes: A61B 2017/00022 Sensing or detecting at the treatment site
• CPC Class Codes: A61B 2017/00026 Conductivity or impedance, e.g. of tissue
• CPC Class Codes: A61B 2017/00053 Mapping
• CPC Class Codes: A61B 2017/00084 Temperature
• CPC Class Codes: A61B 2017/00243 cardiac
• CPC Class Codes: A61B 2017/22051 with an inflatable part, e.g. balloon, for positioning, blocking, or immobilisation A61B2017/22048, A61B2017/3486 take precedence
• CPC Class Codes: A61B 2034/102 Modelling of surgical devices, implants or prosthesis
• CPC Class Codes: A61B 2034/105 Modelling of the patient, e.g. for ligaments or bones
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2034/2068 using pointers, e.g. pointers having reference marks for determining coordinates of body points
• CPC Class Codes: A61B 2034/2072 Reference field transducer attached to an instrument or patient
• CPC Class Codes: A61B 2090/061 for measuring dimensions, e.g. length
• CPC Class Codes: A61B 2090/063 for measuring volume
• CPC Class Codes: A61B 2090/371 with simultaneous use of two cameras
• CPC Class Codes: A61B 2090/376 using X-rays, e.g. fluoroscopy
• CPC Class Codes: A61B 2090/378 using ultrasound
• 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 34/25 User interfaces for surgical systems
• CPC Class Codes: A61B 5/05 Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves impedance plethysmography A61B5/0295; measuring movement of the entire body or parts thereof A61B5/11; detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof A61B5/24
• CPC Class Codes: A61B 5/053 Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61B 5/0538 : invasively, e.g. using a catheter
• CPC Class Codes: A61B 5/063 : using impedance measurements
• CPC Class Codes: A61B 5/066 : Superposing sensor position on an image of the patient, e.g. obtained by ultrasound or x-ray imaging
• CPC Class Codes: A61B 5/068 : using impedance sensors
• CPC Class Codes: A61B 5/287 : Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS]
• CPC Class Codes: A61B 8/06 : Measuring blood flow measuring volume flow in general G01F, e.g. G01F1/66, G01F1/72; measuring speed of fluids in general G01P5/00
• CPC Class Codes: G06T 19/003 : Navigation within 3D models or images

Abstract

A volume of a patient can be mapped with a system operable to identify a plurality of locations and save a plurality of locations of a mapping instrument. The mapping instrument can include one or more electrodes that can sense a voltage that can be correlated to a three dimensional location of the electrode at the time of the sensing or measurement. Therefore, a map of a volume can be determined based upon the sensing of the plurality of points without the use of other imaging devices. An implantable medical device can then be navigated relative to the mapping data.

Claims

1. A method of determining a location of an instrument in a volume, comprising:

evaluating the volume;

determining at least a first section of the volume and a second section of the volume based on the evaluation of the volume;

determining a first characteristic of the first section;

determining a second characteristic of the second section;

placing an instrument in one of the first section or the second section;

searching for the first characteristic or the second characteristic to determine whether at least one of the first characteristic and the second characteristic is present or absent;

determining whether the instrument is located in the first section or the second section based at least on the presence or the absence of the first characteristic or the second characteristic.

2. The method of claim 1, further comprising:

determining a position difference between the first section and the second section; and

determining a position of the instrument;

wherein the instrument is operable to be in a plurality of positions within the location.

3. The method of claim 2, further comprising:

moving the instrument into a heart.

4. The method of claim 3, wherein determining whether the instrument is in the first section or the second section includes predetermining a relative location of a first section and a second section.

5. The method of claim 4, wherein predetermining a relative position of the first section and the second section includes:

determining that a right atrium of the heart is accessible only from a superior venacava, inferior venacava, right ventricle, and coronary sinus ostium;

determining that the right ventricle is only accessible from a right atrium, a pulmonary artery, and a pulmonic valve;

determining that the coronary sinus is only accessible from a right atrium; and

determining that the pulmonary artery is only accessible from a right ventricle.

6. The method of claim 3, wherein determining a first characteristic of a first section includes:

measuring and storing a pulse pressure of the first section;

determining when an electrocardiogram deflection occurs coincident with an electrogram deflection; and

a relative position of the instrument within the volume.

7. The method of claim 6, wherein the first characteristic in the first section includes determining the first characteristic in at least one of a superior venacava, a right atrium, an inferior venacava, a coronary sinus ostium, a tricuspid valve, a right ventricle, a pulmonary artery, and a pulmonic valve in the heart.

8. The method of claim 3, wherein searching for the first characteristic or the second characteristic includes measuring with the instrument placed in the first section or second section of the heart at least one of a pulse pressure, an electrogram, and a position.

9. The method of claim 3, wherein determining whether the instrument is located in the first section or the second section includes:

determining a value of the searched for first characteristic or second characteristic in the respective first or second sections;

comparing the value of the searched for first characteristic or second characteristic with a stored predetermined first characteristic or predetermined second characteristic; and

determining that the value of the searched for first characteristic or second characteristic substantially matches the predetermined first characteristic or the predetermined second characteristic to identify a location of an instrument within the heart.

10. The method of claim 9, further comprising:

providing a processor to execute instructions to compare the searched for first characteristic or second characteristic with the stored predetermined first characteristic or second characteristic; and

outputting to a user the determined location of the instrument.

11. The method of claim 3, wherein in the heart the instrument is determined to have moved from the superior venacava to the right atrium when a measured pulse pressure is nonexistent and when an electrogram (EGM) measured with the instrument includes a deflection substantially coincident with a P-wave of an electrocardiogram (ECG);

wherein in the heart the instrument is determined to have moved from the right atrium to the superior venacava when a measured pulse pressure is nonexistent, an electrocardiogram (EGM) includes substantially no deflections, and a position of the instrument is superior near the heart;

wherein in the heart the instrument is determined to have moved from the right atrium to the inferior venacava when a measured pulse pressure is nonexistent, an electrocardiogram (EGM) includes substantially no deflections, and the position of the instrument is inferior relative to the heart;

wherein in the heart the instrument is determined to have moved from the right atrium to the tricuspid valve when a measured pulse pressure increases to a medium pressure pulse, when an electrocardiogram (EGM) includes a first deflection substantially coincident with a R-wave of the ECG and a second deflection substantially coincident with a P-wave of the ECG;

wherein in the heart the instrument is determined to have moved from the right atrium to the right ventricle when a measured pulse pressure increases significantly, when an electrocardiogram (EGM) includes a deflection substantially coincident with a R-wave of the ECG;

wherein in the heart the instrument is determined to have moved from the right ventricle to the pulmonic artery when a measured pulse pressure decreases to a medium pulse pressure, when an electrocardiogram (EGM) includes a deflection substantially coincident with a P-wave of the ECG;

wherein in the heart the instrument is determined to have moved from the right atrium to the coronary sinus ostium when a measured pulse pressure increases to a small pulse pressure, when an electrocardiogram (EGM) includes a deflection substantially coincident with a P-wave of the ECG, and when the instrument has moved to a lateral position in the heart.

12. A system to determine a location of an instrument in a volume, comprising:

a memory system operable to store information regarding a first characteristic of a first section of the volume and a second characteristic of a second section of the volume;

an instrument to measure the first characteristic and the second characteristic;

a processor to receive an output from the instrument including the measurement of the first characteristic and the second characteristic;

wherein the processor executes instructions to identify if the first characteristic or the second characteristic has been measured;

wherein the processor is operable to identify the location of the instrument as in the first section or the second section based at least on the determination of the presence of the first characteristic or the second characteristic.

13. The system of claim 12, wherein the memory system stores instructions to be executed by the processor to determine what selected electrogram (EGM) deflection is coincident with a selected electrocardiogram (ECG) deflection and when the selected EGM deflection is coincident with the selected ECG deflection to which of the first section or the second section the relationship is related, what pulse pressure value is related to the first section of the second section, and what relative position of the instrument is related to the first section or the second section.

14. The system of claim 12, wherein the instrument includes an electrode operable to measure electrical activity within a heart of a patient to generate an electrogram of the electrical activity;

an electrocardiogram operable to generate electrocardiogram of electrical activity of the heart within the patient;

wherein the processor is operable to compare the electrogram and the electrocardiogram to determine a location of the instrument within the heart of the patient.

15. The system of claim 14, further comprising:

a pulse pressure monitor;

wherein the instrument includes a pressure sensitive portion operable to be affected by a pulse pressure near the pressure sensitive portion of the instrument;

wherein the processor is operable to compare a measured pulse pressure with a stored pulse pressure to determine the location of the instrument.

16. The system of claim 15, further comprising:

a position sensing unit operable with the instrument to determine a position of the instrument;

wherein the processor is operable to compare the determined position of the instrument with a stored position of the instrument to determine the location within the heart of the patient.

17. The system of claim 16;

wherein the location of the instrument includes a specific anatomical location of the instruments and a position includes a relative position of the instrument relative to the patient.

18. The system of claim 17, wherein the position sensing unit includes:

a set of axis electrodes operable to inject a current into the volume;

a driver to inject the current into the volume between the set of axis electrodes;

wherein the instrument includes an electrode operable to sense a voltage due to the injected current into the volume;

wherein the processor is operable to determine an impedance based on the sensed voltage and the injected current to determine the position of the instrument within the volume.

19. A method of determining a location of an instrument in a volume, comprising:

analyzing a heart of a human to determine a first characteristic value in a first location and a second characteristic value in a second section;

storing the determined the first characteristic value in the first location and the second characteristic value in the second section;

placing an instrument in one of the first section or the second section;

determining a procedure value for the characteristic including whether the characteristic is present or absent;

determining whether the instrument is located in the first section or the second section based at least on the procedure value of the characteristic.

20. The method of claim 19, wherein the characteristic includes a pulse pressure, an electrogram of electrical activity in the heart, a position of the instrument relative to the heart, or combinations thereof.

21. The method of claim 20, wherein the determination of whether the instrument is in the first section or the second section includes determining whether the instrument is in a superior venacava, a right atrium, an inferior venacava, a tricuspid valve, a right ventricle, a pulmonic valve, or a pulmonary artery.