[go: up one dir, main page]

WO2000068637A1 - Dispositif pour catheter - Google Patents

Dispositif pour catheter Download PDF

Info

Publication number
WO2000068637A1
WO2000068637A1 PCT/GB2000/001429 GB0001429W WO0068637A1 WO 2000068637 A1 WO2000068637 A1 WO 2000068637A1 GB 0001429 W GB0001429 W GB 0001429W WO 0068637 A1 WO0068637 A1 WO 0068637A1
Authority
WO
WIPO (PCT)
Prior art keywords
catheter
magnetic
incorporating
coil
calibration
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/GB2000/001429
Other languages
English (en)
Inventor
Andrew Dames
Edward Grellier Colby
James Mark Carson England
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sentec Ltd
Original Assignee
Sentec Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from GBGB9909332.0A external-priority patent/GB9909332D0/en
Application filed by Sentec Ltd filed Critical Sentec Ltd
Priority to AU45796/00A priority Critical patent/AU4579600A/en
Publication of WO2000068637A1 publication Critical patent/WO2000068637A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
    • G01B7/004—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring coordinates of points
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/06—Devices, other than using radiation, for detecting or locating foreign bodies ; Determining position of diagnostic devices within or on the body of the patient
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/06—Devices, other than using radiation, for detecting or locating foreign bodies ; Determining position of diagnostic devices within or on the body of the patient
    • A61B5/061—Determining position of a probe within the body employing means separate from the probe, e.g. sensing internal probe position employing impedance electrodes on the surface of the body
    • A61B5/062—Determining position of a probe within the body employing means separate from the probe, e.g. sensing internal probe position employing impedance electrodes on the surface of the body using magnetic field
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
    • A61M25/00—Catheters; Hollow probes
    • A61M25/01—Introducing, guiding, advancing, emplacing or holding catheters
    • A61M25/0105—Steering means as part of the catheter or advancing means; Markers for positioning
    • A61M25/0127—Magnetic means; Magnetic markers
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
    • G01D5/14—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage
    • G01D5/20—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature
    • G01D5/204—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature by influencing the mutual induction between two or more coils
    • G01D5/2086—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature by influencing the mutual induction between two or more coils by movement of two or more coils with respect to two or more other coils
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B90/00—Instruments, implements or accessories specially adapted for surgery or diagnosis and not covered by any of the groups A61B1/00 - A61B50/00, e.g. for luxation treatment or for protecting wound edges
    • A61B90/39—Markers, e.g. radio-opaque or breast lesions markers
    • A61B2090/3954—Markers, e.g. radio-opaque or breast lesions markers magnetic, e.g. NMR or MRI
    • A61B2090/3958—Markers, e.g. radio-opaque or breast lesions markers magnetic, e.g. NMR or MRI emitting a signal

Definitions

  • This invention relates to the field of position measurement applied to location of a small object, specifically an object or objects mounted into a catheter tip.
  • the invention described is a catheter incorporating miniature magnetic field detection devices.
  • Inductive measurement systems are inherently not affected by human tissue as this is mostly composed of non-conductive, non-ferromagnetic material. Therefore placing the patient into the interrogation volume will not cause position measurement errors.
  • the invention requires a miniature '3 orthogonal axis' coil to be incorporated within the catheter tip.
  • the construction techniques describes allows a suitably compact air-cored or ferrite-cored coil configuration. Further the use of a miniature coil assembly generates extremely low level signals and these are transported to the processing electronics with mii ⁇ nal interference from the reference magnetic field. This is achieved by the construction of a specialised lead incorporated into the catheter.
  • an apparatus for detecting the position and pointing angle of a catheter tip wherein a miniature, 3-axis orthogonal coil set is incorporated into the catheter tip.
  • a specialised cable is incorporated to transport the voltage induced in the receiver coil set by the reference magnetic field with minimal susceptibility to inductive or capacitive interference.
  • Figure 1 illustrates the construction of the catheter
  • Figure 2 shows the coil assembly
  • Figure 3 illustrates the system for generating output signals from the catheter and converting these into position and orientation information.
  • the catheter tip, 1, has a small coil assembly, 2 placed within the inside of a 10 french catheter.
  • the coil assembly, 2, is wound onto a block of plastic, 3, with dimensions 4mm long and 2mm square section.
  • the coils are 40 turns of 50 ⁇ m enamelled copper wire tight wound as single layer coil and with the connections brought together.
  • the catheter, 7, has the coil assembly placed at the tip, 8.
  • the coil assembly is connected to the end of the catheter by fine 50um copper wire.
  • the cable consists of three twisted pairs, with each twisted pair constructed from two 50um wire with 25 twists per cm. The three twisted pairs are loosely twisted with 3 twists per cm.
  • the length of the twisted cable must be kept relatively short, to avoid unwanted coupling between the cable and the transmit coil assembly, 10, which could distort the signals intentionally coupled into the coil assembly at the catheter tip, 8. Two methods may be used to achieve this.
  • a step-up toroidal transformer mounted in a small, magnetically shielded enclosure, is used to increase the signal levels relative to the unintended coupling.
  • a suitable transformer is based on a Philips TN14/9/5-3E25 core, wound with 100 ⁇ m wire with a turns ratio of 15:60. For optimum performance, this is achieved using 15 turns of twisted 5-strand wire. Four strands are connected in series to form 60 turns of secondary, and the fifth strand forms the primary.
  • the second method is to use a low-noise in-line preamplifier, again mounted in a magnetically screened enclosure. This second method is particularly advantageous when long cable lengths are required between the catheter, 7, and the signal processing, 11.
  • the coil assembly within the catheter tip, 8, is placed within the vector fields, 9, generated by one or more transmit coil assemblies, 10.
  • Each transmitter coil assembly, 10, comprises three orthogonal coils of wire, and generates three dipole AC magnetic field patterns at different frequencies, for example 10, 11 and 12kHz.
  • the processing electronics, 11, generates the required drive signals for the transmitter antenna and provides the receive signal processing. .
  • the drive amplifiers for the coils are current-mode, and the coils are series-resonated for efficiency and harmonic purity.
  • the signal processing calculates the position and orientation (6 degrees of freedom) defining the catheter tip position relative to the transmitter antenna
  • Each transmitter coil generates a field pattern with a near-dipole distribution in the far field.
  • Each transmitter coil runs at a different frequency.
  • all the transmitters are derived from a common clock signal, such that for certain time period (e.g. 1 ms) , an integral number of cycles of each transmitter can be counted. This is advantageous for synchronous demodulation.
  • the three receiver coils, 2 together measure the field vector (i.e. amplitude and direction) at the catheter tip of each of the transmitted frequencies.
  • a phase-sensitive method of demodulation is used in the preferred embodiment, using the detection phase determined as part of the transmit-receive calibration process.
  • For each orthogonal transmitter set there are nine measured coupling co-efficients (a 3x3 coupling matrix) and these are processed using the known field patterns from a magnetic dipole, and measured field values where required, to calculate the best estimate of the catheter position and orientation.
  • Calibration coefficients are incorporated into the processing to correct for imperfections in the transmit and receive coils, and field distortions caused by either fixed position ferromagnetic or conductive materials placed widiin the operating volume.
  • the calibration of the catheter and the calibration of the transmitter coil and operating environment are carried out separately.
  • the catheter calibration records the sensitivity and orthogonality of the catheter coils at the operating frequencies. This is achieved independently of the transmitter using a calibrated uniform field generator.
  • the transmit field is mapped using a specialised test jig that allows translation of a calibrated receive coil assembly within the operating volume.
  • the jig records the known physical position of the receive coil assembly.
  • the magnetic fields are characterised over the interrogation volume at a number of different points, and these values are placed in a calibration database in the processing unit, 11.
  • the three coils, 4, 5, 6, in the catheter are substantially orthogonal.
  • the "orthogonality matrix" for the three axis receiver coil is a 3x3 matrix, R, whose columns represent the field coupling from three unit orthogonal dipoles.
  • a uniform field may be generated by a set of Helmholtz coils to determine the calibration matrix R, using the method described below.
  • the coil assembly, 2 is placed at the centre of a three-axis Helmholtz (or similar) coil set, driven at the standard transmit drive frequencies used for the transmitter coil set.
  • a jig is used to constrain the possible orientations of the coil assembly, 2, to be orthogonal to each other, and (nominally) aligned with the Helmholtz coil set axes.
  • a series of measurements are taken of the 3x3 coupling matrix between the transmit and receive coils in four different, orthogonal orientations - one nominally a capitad, and three in which a 90 ⁇ rotation has been applied. In each case, there will be three nominal terms in which the coupling is large, and six near- zero terms.
  • the ratio between the nominal coupling (+/-1) and the actual coupling is measured, together with the correct detection phase. This allows for the correction of different drive levels and drive phases between the three driven coils - i.e. it allows calibration of the Helmholtz coils themselves.
  • the coupling matrix corrected for different transmitter drive levels, should ideally be diagonal with all elements equal. In practice, it will be neither diagonal, nor will it have equal magnitude elements, and is referred to as the orthogonality matrix, R , of the receiver coil set.
  • the calibration data may be stored on a data device associated with the catheter. If this forms part of the catheter itself, it may be stored in an electronic memory chip incorporated into the catheter or its connector, and read by the processing box, 11.
  • the data may alternatively be part of the catheter packaging, in the form of a smart card, bar code, EPROM or floppy disc, which can again be read by the processing box, 11.
  • Non-orthogonality and receiver gain errors are corrected in the measurement system by multiplying the measured 3x3 transmit / receive coupling matrix by the inverse of the measured calibration orthogonality/gain matrix , R .
  • the first step is to measure the field vectors over an array of points within the measurement volume - i.e. a calibration. This is ideally achieved using a calibrated three-axis receiver coil of known orthogonality, whose position and orientation (in the frame of reference of the transmitter coil set) is measured using a suitable co-ordinate measurement apparatus. This measurement should include the phase of the AC field vector, as the phase of the fields may vary in the presence of eddy- currents in metal objects.
  • the raw measurement data consists of a 3x3 matrix of coupling coefficients, Y, between the receiver coils and the transmitter coils. This is corrected for receiver orthogonality and gain errors as described above using the equation
  • the rows of Y' are the couplings into the x, y and z receiver coils, whilst the columns represent the three transmit coil vectors in the receiver frame of reference. Therefore, the three transmit field amplitudes at the receiver (A-, A y and A may be obtained simply from magnitudes of the three column vectors of Y', and the three angles between the fields (#-, ⁇ y and #) can be obtained from the dot products of the columns.
  • These six values are the basic numbers which are used to resolve the position of the receiver coil. A seventh useful number is
  • Data from the coil calibration measurements may not line on a regular Cartesian grid.
  • a favourable method to store the data is as a cross-linked "tree" structure, in which each point stores references to the locations of a number of nearest neighbours (in physical space), which may or may not be uniformly spaced.
  • the data stored from the calibration at each point consists of the following ten data items, / .J :
  • the principle of the distortion correction process is to convert the ( Airri A y and A ⁇ ) and ( ⁇ a ⁇ y and 6 into an equivalent seat of measured items, M 0 .M 9 .
  • An error function is defined which is the sum of the squares of the differences between the seven measured terms and the seven stored calibration terms: where w- is a weighting factor (which may optionally depend on the position).
  • w- is a weighting factor (which may optionally depend on the position).
  • a search algorithm is used which determines the nearest calibration point to the unknown measurement.
  • a number of alternative methods may then be applied, depending on the degree of the field distortions, the number of calibration points and the accuracy required.
  • a multi-variate non-linear numerical rriinimisation algorithm (such as Powell's method) is used to determine the point (x,y,z) close to this nearest calibration point where the error in minimum.
  • This search can be constrained to the surface of a sphere by the seventh term, hi ).
  • Interpolation (such as quadratic interpolation) is used to determine values of the seven data items in between the measured data points, such that the error function may be calculated at arbitrary points in space. The outcome of this process is an estimated (x,y,z) position.
  • the orientation is calculated by back-substitution: the interpolated values of D ⁇ .J 6 are used to calculate the field vectors at the point of interest.
  • a numerical method is used to calculate the rotation matrix required to operate on this set of field vectors to give the closest match to the (corrected) measured matrix Y ⁇
  • Method 2 An alternative method involves storing the local transmitter non-orthogonality matrix, X , at discrete, known calibration points, using a previously calibrated receiver coil assembly (with orthogonality matrix R ).
  • the expected coupling matrix, Y e can be calculated from the known position and orientation of the receiver coil assembly with respect to the transmitter coil assembly.
  • the measured coupling, Y , and the expected coupling, Y e are related by the equation:
  • the coupling matrix, Y " corresponds to a near-ideal situation involving perfect dipoles.
  • a number of standard solution methods to the problem may then be used to deterrnine both the orientation and to calculate the position.
  • One solution is to use an iterative method to correct for the position.
  • the transmit orthogonality matrix, X from this point is then used to correct the measured data, and the resulting matrix is used to calculate the first estimate of position.
  • An iterative process can then be applied as follows: the position estimate is used to obtain an interpolated orthogonality matrix at this position. This is applied to the coupling matrix Y ', and this is used to re-calculate the position. This process is repeated until the solution converges to an acceptable accuracy.
  • This calibration data is related to the installed configuration and is an installation process.
  • the data is stored within the processing system, 11.
  • the receive coil assembly in the catheter tip measures all the field vectors and can again estimate the catheter position and orientation using an error minimisation algorithm.
  • An additional benefit of this configuration is that distortions to the magnetic field caused by moveable conducting or ferrous material can be better accommodated.
  • the increased number of measurands allow for the field effects of the unknown moveable object to be better approximated.
  • the receiver coil assembly is a single coil.
  • a miriimum of six transmit coils are required for this measurement, typically as two sets of three orthogonal coils in different locations. It is not possible to resolve orientations about the axis of the catheter using this configuration, but the coil can be made more compact.
  • Frequency multiplexing is again used to generate the magnetic dipole field patterns in the operating volume. Further combinations of transmit and receive coil configurations randomly spaced and orientated around the operating volume are possible, provided they provide sufficient measurands to provide a unique soluble position and orientation.
  • two or more receive coil assemblies spaced apart within the catheter. These allow for the path of the catheter to be measured. This can be extended to multiple instances of receive coil assemblies within the catheter that will allow the complete catheter 'path' to be measured, interpolating the path between points using a spline fit.
  • a further embodiment of the catheter device is where the coil assembly is fitted to a semirigid member that can move within the catheter tube.
  • the coil assembly may be moved along the inside of the catheter, and this allows the path of the catheter to be determined.
  • the receiver coil may be used as a transmitter and visa- versa.
  • Improved signal levels can be obtained by using f errite cores in any of the coils.

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Veterinary Medicine (AREA)
  • Animal Behavior & Ethology (AREA)
  • Public Health (AREA)
  • Biomedical Technology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Biophysics (AREA)
  • General Health & Medical Sciences (AREA)
  • Medical Informatics (AREA)
  • Surgery (AREA)
  • Molecular Biology (AREA)
  • Pathology (AREA)
  • Human Computer Interaction (AREA)
  • General Physics & Mathematics (AREA)
  • Pulmonology (AREA)
  • Anesthesiology (AREA)
  • Hematology (AREA)
  • Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
  • Media Introduction/Drainage Providing Device (AREA)
  • Endoscopes (AREA)

Abstract

L'invention concerne un cathéter, lequel comprend des moyens de détection de champ magnétique et est caractérisé en ce que, lors de son utilisation dans une chirurgie à caractère vulnérant minimal, il permet une détermination de sa position et de son orientation.
PCT/GB2000/001429 1999-04-23 2000-04-25 Dispositif pour catheter Ceased WO2000068637A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU45796/00A AU4579600A (en) 1999-04-23 2000-04-25 Catheter Device

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
GBGB9909332.0A GB9909332D0 (en) 1999-04-23 1999-04-23 Employment contract
GB9909332.0 1999-04-23
GB9919979.6 1999-08-24
GBGB9919978.8A GB9919978D0 (en) 1999-04-23 1999-08-24 Improved catheter device
GB9919978.8 1999-08-24
GBGB9919979.6A GB9919979D0 (en) 1999-04-23 1999-08-24 Orthogonality correction algorithm

Publications (1)

Publication Number Publication Date
WO2000068637A1 true WO2000068637A1 (fr) 2000-11-16

Family

ID=27269705

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB2000/001429 Ceased WO2000068637A1 (fr) 1999-04-23 2000-04-25 Dispositif pour catheter

Country Status (2)

Country Link
AU (1) AU4579600A (fr)
WO (1) WO2000068637A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6427079B1 (en) 1999-08-09 2002-07-30 Cormedica Corporation Position and orientation measuring with magnetic fields
EP1370826B1 (fr) * 2001-03-19 2013-04-24 ELEKTA AB (publ.) Determination de la position d'objets
US8886288B2 (en) 2009-06-16 2014-11-11 MRI Interventions, Inc. MRI-guided devices and MRI-guided interventional systems that can track and generate dynamic visualizations of the devices in near real time
US9259290B2 (en) 2009-06-08 2016-02-16 MRI Interventions, Inc. MRI-guided surgical systems with proximity alerts
EP3643234A1 (fr) * 2018-10-24 2020-04-29 Biosense Webster (Israel) Ltd. Étalonnage à la volée pour la localisation et l'orientation d'un cathéter

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3660648A (en) 1969-10-15 1972-05-02 Northrop Corp Angular rate coordinate transformer
US3868565A (en) 1973-07-30 1975-02-25 Jack Kuipers Object tracking and orientation determination means, system and process
US3983474A (en) 1975-02-21 1976-09-28 Polhemus Navigation Sciences, Inc. Tracking and determining orientation of object using coordinate transformation means, system and process
US4017858A (en) 1973-07-30 1977-04-12 Polhemus Navigation Sciences, Inc. Apparatus for generating a nutating electromagnetic field
US4054881A (en) 1976-04-26 1977-10-18 The Austin Company Remote object position locater
US4298874A (en) 1977-01-17 1981-11-03 The Austin Company Method and apparatus for tracking objects
WO1994004938A1 (fr) * 1992-08-14 1994-03-03 British Telecommunications Public Limited Company Dispositif de localisation d'une position
US5645065A (en) * 1991-09-04 1997-07-08 Navion Biomedical Corporation Catheter depth, position and orientation location system
US5729129A (en) * 1995-06-07 1998-03-17 Biosense, Inc. Magnetic location system with feedback adjustment of magnetic field generator
US5833608A (en) * 1993-10-06 1998-11-10 Biosense, Inc. Magnetic determination of position and orientation

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3660648A (en) 1969-10-15 1972-05-02 Northrop Corp Angular rate coordinate transformer
US3868565A (en) 1973-07-30 1975-02-25 Jack Kuipers Object tracking and orientation determination means, system and process
US4017858A (en) 1973-07-30 1977-04-12 Polhemus Navigation Sciences, Inc. Apparatus for generating a nutating electromagnetic field
US3983474A (en) 1975-02-21 1976-09-28 Polhemus Navigation Sciences, Inc. Tracking and determining orientation of object using coordinate transformation means, system and process
US4054881A (en) 1976-04-26 1977-10-18 The Austin Company Remote object position locater
US4298874A (en) 1977-01-17 1981-11-03 The Austin Company Method and apparatus for tracking objects
US5645065A (en) * 1991-09-04 1997-07-08 Navion Biomedical Corporation Catheter depth, position and orientation location system
WO1994004938A1 (fr) * 1992-08-14 1994-03-03 British Telecommunications Public Limited Company Dispositif de localisation d'une position
US5833608A (en) * 1993-10-06 1998-11-10 Biosense, Inc. Magnetic determination of position and orientation
US5729129A (en) * 1995-06-07 1998-03-17 Biosense, Inc. Magnetic location system with feedback adjustment of magnetic field generator

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6427079B1 (en) 1999-08-09 2002-07-30 Cormedica Corporation Position and orientation measuring with magnetic fields
EP1370826B1 (fr) * 2001-03-19 2013-04-24 ELEKTA AB (publ.) Determination de la position d'objets
US9259290B2 (en) 2009-06-08 2016-02-16 MRI Interventions, Inc. MRI-guided surgical systems with proximity alerts
US9439735B2 (en) 2009-06-08 2016-09-13 MRI Interventions, Inc. MRI-guided interventional systems that can track and generate dynamic visualizations of flexible intrabody devices in near real time
US8886288B2 (en) 2009-06-16 2014-11-11 MRI Interventions, Inc. MRI-guided devices and MRI-guided interventional systems that can track and generate dynamic visualizations of the devices in near real time
EP3643234A1 (fr) * 2018-10-24 2020-04-29 Biosense Webster (Israel) Ltd. Étalonnage à la volée pour la localisation et l'orientation d'un cathéter
JP2020065928A (ja) * 2018-10-24 2020-04-30 バイオセンス・ウエブスター・(イスラエル)・リミテッドBiosense Webster (Israel), Ltd. カテーテルの位置及び方位のオンザフライ較正
US10973588B2 (en) 2018-10-24 2021-04-13 Biosense Webster (Israel) Ltd. On-the-fly calibration for catheter location and orientation
JP7326110B2 (ja) 2018-10-24 2023-08-15 バイオセンス・ウエブスター・（イスラエル）・リミテッド カテーテルの位置及び方位のオンザフライ較正

Also Published As

Publication number Publication date
AU4579600A (en) 2000-11-21

Similar Documents

Publication Publication Date Title
EP1269111A1 (fr) Reperage d'objet au moyen d'un detecteur unique ou d'une paire de detecteurs
US5592939A (en) Method and system for navigating a catheter probe
US20020062203A1 (en) Object tracking using a single sensor or a pair of sensors
US8954293B2 (en) Method and arrangement for reconstructing the source of an electromagnetic field
CA2475918C (fr) Detection des perturbations dues aux metaux dans un systeme magnetique de suivi
JP2579570B2 (ja) プローブシステム
US7835779B2 (en) Magnetic tracking system
US7026927B2 (en) Receiver used in marker localization sensing system and having dithering in excitation pulses
US6789043B1 (en) Magnetic sensor system for fast-response, high resolution, high accuracy, three-dimensional position measurements
US20140043017A1 (en) Electromagnetic position and orientation sensing system
O’Donoghue et al. Catheter position tracking system using planar magnetics and closed loop current control
US9335359B2 (en) Far electromagnetic field estimation method and apparatus, and near electromagnetic field measurement apparatus
TW201321782A (zh) 多軸標識定位器
WO1997042517A1 (fr) Etalonnage d'element rayonnant
US20060071669A1 (en) Method of measuring electric field distribution and electric field distribution measuring instrument
JPH09503067A (ja) 非双極子磁界を使用して位置及び配向を測定するための装置
JP2005037386A5 (fr)
CN101897585A (zh) 具有磁阻传感器的手术导航系统
EP3304112B1 (fr) Système de poursuite de la position et de l'orientation d'un objet dans un appareil à résonance magnétique (rm)
JP2005529699A (ja) Ｒｆコイルアレイを具備するｍｒシステム
IL168461A (en) Method of compensation for eddy current distortion in an ac magnetic tracking system
WO2000068637A1 (fr) Dispositif pour catheter
EP3060297B1 (fr) Estimation de l'épaisseur de peau par aimant implanté en dessous
US20230087433A1 (en) Reducing interference from magnetic resonance tomography units
US20240337475A1 (en) Coil geometry for an electromagnetic tracking system

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AL AM AT AU AZ BA BB BG BR BY CA CH CN CR CU CZ DE DK DM EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

NENP Non-entry into the national phase

Ref country code: JP