WO2008110553A2 - Procédé de détermination de position d'un instrument médical - Google Patents

Procédé de détermination de position d'un instrument médical Download PDF

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Publication number
WO2008110553A2
WO2008110553A2 PCT/EP2008/052873 EP2008052873W WO2008110553A2 WO 2008110553 A2 WO2008110553 A2 WO 2008110553A2 EP 2008052873 W EP2008052873 W EP 2008052873W WO 2008110553 A2 WO2008110553 A2 WO 2008110553A2
Authority
WO
WIPO (PCT)
Prior art keywords
determining
measured values
determined
magnetic field
calculated value
Prior art date
Application number
PCT/EP2008/052873
Other languages
German (de)
English (en)
Other versions
WO2008110553A3 (fr
Inventor
Rainer Graumann
Original Assignee
Siemens Aktiengesellschaft
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
Application filed by Siemens Aktiengesellschaft filed Critical Siemens Aktiengesellschaft
Publication of WO2008110553A2 publication Critical patent/WO2008110553A2/fr
Publication of WO2008110553A3 publication Critical patent/WO2008110553A3/fr

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Classifications

    • 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
    • A61B90/36—Image-producing devices or illumination devices not otherwise provided for
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B34/00—Computer-aided surgery; Manipulators or robots specially adapted for use in surgery
    • A61B34/20—Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B34/00—Computer-aided surgery; Manipulators or robots specially adapted for use in surgery
    • A61B34/70—Manipulators specially adapted for use in surgery
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B34/00—Computer-aided surgery; Manipulators or robots specially adapted for use in surgery
    • A61B34/70—Manipulators specially adapted for use in surgery
    • A61B34/73—Manipulators for magnetic surgery
    • 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 probes 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
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B34/00—Computer-aided surgery; Manipulators or robots specially adapted for use in surgery
    • A61B34/20—Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
    • A61B2034/2046—Tracking techniques
    • A61B2034/2051—Electromagnetic tracking systems
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B34/00—Computer-aided surgery; Manipulators or robots specially adapted for use in surgery
    • A61B34/70—Manipulators specially adapted for use in surgery
    • A61B34/73—Manipulators for magnetic surgery
    • A61B2034/731—Arrangement of the coils or magnets
    • A61B2034/732—Arrangement of the coils or magnets arranged around the patient, e.g. in a gantry
    • 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
    • A61B90/36—Image-producing devices or illumination devices not otherwise provided for
    • A61B90/361—Image-producing devices, e.g. surgical cameras

Definitions

  • the invention relates to a method for determining the position of a medical instrument, in particular an endoscopy capsule, having at least three mutually orthogonal receiving coils assigned to a position determining device generating a spatially variable position determining magnetic field by means of field generating means.
  • an electromagnetic navigation system based on an LC resonant circuit has been proposed.
  • the method is characterized by a sufficient stability against magnetic interference fields, however, only a low accuracy can be achieved.
  • only five degrees of freedom of position and orientation of the instrument can be determined with this method, a rotation about the longitudinal axis can not be determined.
  • the use of an electromagnetic navigation system based on orthogonal receiving coils, which are integrated in or arranged on the medical instrument, in particular the endoscopy capsule, is known. With these receiving coils, an external, location-dependent position determining magnetic field is detected and a position determined from the position measured values.
  • this method is very susceptible to external noise, so that it can easily lead to large errors in the position determination.
  • a magnet for example a permanent magnet
  • a very strong magnetic field in the range of about 0.1 T is used.
  • the already mentioned position determining magnetic field is only in the mT range and has a fairly high frequency. The fields of the much stronger navigation magnetic field disturb the weak position determining magnetic field significantly, so that is to be expected with large errors.
  • the invention is therefore based on the object of specifying a method for position determination using a position determining magnetic field and associated receiving coils, which provides reliable position information even in the presence of external interference fields.
  • At least one stationary reference coil is provided with respect to the field generating means, in which method: first reference measured values of the reference coil are recorded with the position determining magnetic field switched on, after which the position is determined continuously at the same time position readings of the receiving coils and second reference measured values are taken by the reference coil,
  • At least one calculated value describing a possible interference field is determined
  • the position is determined taking into account the calculated value.
  • the method is advantageously applicable when a magnetically navigable instrument is used with a magnet that is responsive to a navigation magnetic field generating an interference field for the position determination magnetic field and generated by a navigation device, the first reference measured values being recorded when the navigation magnetic field is switched off.
  • the proposed, temporally indeed variable navigation magnetic field of a navigation device forms the main interfering field, which, in its order of magnitude, as explained in the introduction, is far stronger than the position-determining magnetic field. Since the first reference measured values have been recorded when the navigation magnetic field has been switched off, the interference of the navigation magnetic field can be deduced when the second reference measured values are taken later.
  • first reference measured values of the reference coil are initially recorded when the position determining magnetic field is switched on.
  • two embodiments are conceivable, which can also be connected to each other.
  • it makes sense of course, to record the first reference measured values if there are as far as possible no external interference fields.
  • the interference fields are mainly determined by a navigation magnetic field, such a point makes sense and leads to a significant improvement in the position determination.
  • the reference coil since its location is known, also serves to calibrate the position determining device.
  • information about the presence and the strength of one or more interference fields can be obtained by a continuous comparison of the first reference measured values with the second reference measured values. This is expressed on the basis of a calculated value which describes at least one possible interference field.
  • a calculated value which describes at least one possible interference field.
  • a plurality of calculated values may also be given. The calculated value or the calculated values obtained can then be used advantageously to improve the position determination.
  • the current position measurement values are discarded. If, during the course of the method, the interfering fields become too large, which can be determined on the basis of the calculated value, no positions from the current position measured values are determined at this point in time since the position obtained would be too strongly error-related. Roughly wrong positions can be advantageously prevented in this way. If the interference fields sink to a lower value again, the position is determined again.
  • a correction of the position measured values or of a position determined therefrom is carried out on the basis of the calculated value.
  • the error in the position determination occurring due to the interference fields can be calculated out again on the basis of the calculated value, so that the position determination as a whole becomes more accurate and a high degree of reliability is given even in the presence, for example, of a navigation magnetic field.
  • a quality value indicating the accuracy of the position determination is determined from the calculated value and assigned to the determined position. The quality value is then displayed to an operator at the same time as the determined position so that it can immediately recognize possible inaccuracies due to interference fields.
  • the comparison can preferably be carried out by subtracting the first and second reference measured values to form a difference value.
  • the portion of the position-determining magnetic field predetermined by the first reference measured values is subtracted out, so that the difference value describes the interference field or the disturbing field influence at the location of the respective reference coil.
  • a location-dependent calculation value for the interference field is determined on the basis of the difference values of a plurality of spatially offset reference coils, in particular using Bessel functions and / or spherical functions, wherein the location dependence is taken into account in the position determination .
  • the reference measured values influencing interference fields at a plurality of different locations in the area of the position-determining device it is therefore possible to model the corresponding interference field over the entire relevant area.
  • spherical functions and / or Bessel functions can be used.
  • a location-dependent calculation value is obtained, which at the appropriate time reflects the strength and orientation of the disturbance magnetic fields at arbitrary points in the region of the position determination.
  • the location dependence thus obtained can advantageously be taken into account in the position determination, in particular by examining the location or the area where the medical instrument is actually located for interference fields.
  • a) a first position is first determined from the position measurement values, after which b) the calculated value at the first position is calculated and used to correct the position measurement values, after which c) a second, corrected position is determined. Accordingly, it will first be averages which interference fields, as described by the calculation value, are present at the position described by uncorrected position measurement values. These can then be used to correct the position measurements and determine the corrected position. In a particularly preferred embodiment, this correction is carried out iteratively, which means that the steps b) and c) are repeated at least once with the second position as the first position.
  • Sufficiently accurate results for the position can be achieved in two to three iteration steps if the first position is exactly the same. In this way one approaches the actual position of the medical instrument.
  • a position determined at an earlier point in time is taken into account.
  • the immediately previously determined position can be considered. If, for example, a first position is determined from the current position measurement values which, in view of the immediately preceding determined position of the medical instrument, could not possibly have been reached, the position determined from the position measurement values can also be completely rejected and instead the last known position of the medical position Instruments are used as the first position in step b), so that more accurate position values can be obtained.
  • the reference coils used in the method need not be additionally added to a medical examination or treatment device with a position-determining device, but at least one registration coil fixedly provided for registering coordinate systems can be used as the reference coil. It is only relevant that the coils used as reference coils are arranged stationarily with respect to the position determining magnetic field. If more than three receiving coils are provided on the medical instrument, the method according to the invention can also be used for improved determination of an orientation of the instrument taking into account the calculated value. Then, an orientation of the instrument is determined in consideration of the calculated value in more than three receiving coils.
  • the invention also relates to a position determination device for determining the position of a medical instrument, in particular an endoscopy capsule, comprising a field generating means for generating a position determining magnetic field, at least three receiving coils arranged orthogonally to one another in or on the medical instrument, at least one reference coil stationary relative to the field generating means and a control device which is designed for carrying out the method according to the invention.
  • a position determination device for determining the position of a medical instrument, in particular an endoscopy capsule, comprising a field generating means for generating a position determining magnetic field, at least three receiving coils arranged orthogonally to one another in or on the medical instrument, at least one reference coil stationary relative to the field generating means and a control device which is designed for carrying out the method according to the invention.
  • FIG. 1 is a schematic diagram of a medical treatment and / or examination device with a position determining device according to the invention
  • Fig. 2 is a flowchart of the method according to the invention.
  • Fig. 3 is a flowchart for a possible correction method.
  • Fig. 1 shows a medical treatment and / or examination device 1, which is a position-determining device according to the present invention.
  • a medical instrument here an endoscopy capsule 2
  • the endoscopy capsule 2 comprises a permanent magnet 3 and three receiving coils 4 arranged orthogonally to one another.
  • the permanent magnet 3 is associated with a navigation device 5 which generates a navigation magnetic field which enables a movement and / or orientation of the endoscopy capsule 2 in the body of a patient.
  • the navigation device 5 is designed like a tube here. Within the navigation device 5, a very strong magnetic navigation field is generated for navigation of the endoscopy capsule 2 via suitable coils (not shown) which, for example, can be in the range of 0.1 T and considerably disturb weaker fields.
  • the receiving coils 4 are associated with the position determining device. This also includes in a conventional manner a field generating means 6 for generating a position determining magnetic field.
  • the receiving coils 4 measure the position-determining magnetic field, which is location-dependent, at its current position, ie the position of the endoscopy capsule 2, whereupon a position can be determined from the position measured values.
  • the field generating means 6 is arranged for example on the patient couch 12 and generates a rather weak magnetic field of a strength of a few mT.
  • the position-determining device further comprises twelve reference coils 8, which are arranged stationarily with respect to the position-determining magnetic field, that is to say the field-generating means 6. A part of the reference coils are arranged on the navigation device 5, a further part on the patient couch 12. Of course, it is also possible to attach the reference coils 8 to another location or completely to the navigation device 5 or the patient bed 12. Also, a larger or smaller number of reference coils 8 is conceivable.
  • the reference coils 8 can also be registration coils provided for registration of coordinate systems anyway.
  • the position determining magnetic field is always the same size at its respective location, so that a statement about possible interference fields can be made by comparing measured values of the reference coils 8. This is used in the position-determining device according to the invention for determining a calculated value describing the interference fields.
  • the device 1 further comprises a control device 9, which controls the operation of the navigation device 5, the position determination device and optionally further components.
  • the control device 9 is associated with a display means 10 and an input device 11. Furthermore, the control device 9 is designed for carrying out the method for position determination, as will now be explained in more detail with reference to FIGS. 2 and 3.
  • Fig. 2 shows a flowchart of the method according to the invention.
  • first reference measurement values are received by the reference coils 8 in a step S1. This happens in each case with the navigation magnetic field off, but can be carried out with particular advantage, however, if the Positioning device is calibrated anyway.
  • the first reference measured values thus give the values of the position-determining magnetic field at the reference coils 8 as unaltered as possible from interference fields. If interference fields subsequently occur, their effects can be read off from a comparison with these first reference measured values.
  • step S2 second reference measurement values from the reference coils 8 and position measurement values from the reception coils 4 are recorded simultaneously in step S2.
  • the calculated value is then determined in step S3. This can be done, for example, by forming a difference between the first reference values and the current second reference measured values. Then, the proportion of the position determining magnetic field is subtracted out.
  • step S4 in the sense of a "use-no-use" decision, it is checked whether the calculated value, which indicates the strength of the fault fields, is greater than a threshold value, and if this is the case, then no meaningful ones can be given due to the strong interference fields Positions are determined, the current position measurement values are discarded (step S5) and the process is resumed from step S2.
  • step S4 If it has been determined in step S4 that the interference fields are low enough to make a current position determination, the position determination is carried out with correction and / or upon determination of a quality value in step S6. A to be determined taking into account the calculated value
  • Quality value indicates how reliably the determined position actually takes into account the current interference fields. is lent.
  • a correction of the position measurement data or the position determined therefrom can take place.
  • FIG. 3 An example of such a correction process is shown in the flowchart in FIG. 3.
  • a location-dependent calculated calculation value is assumed. Since, due to the larger number of reference coils i attached to different locations, reference values are available from all these locations, a location-dependent calculation value can be determined assuming a model. This model may for example be based on ball functions and / or Bessel functions. One then obtains an arithmetic value which specifies a measure for the possibly presently existing interference fields for different locations. If such a location-dependent calculation value is present, then the method according to FIG. 3 can be carried out.
  • step S6a a first position is determined from the position measurement values. This takes place in the manner conventionally known.
  • step S6b the location-dependent calculated value is then evaluated at the first position just determined.
  • the position measurement values can be suitably corrected in step S6c at precisely this first position.
  • step S6d a second corrected position can be determined from the corrected position measurement values. This can already be the position to be output as the final result, but several iterations can also be performed.
  • step S6e the second position is set as the new first position and steps S6b to S6d are repeated. Only a few iterations can be used to achieve great accuracy.
  • the method according to FIG. 3 it also makes sense, in particular, to take into account previously determined positions, in particular the last previously determined position. This can be a plausibility check, which means if the If the first position deviates too far from the last position, there is a discrepancy. Then it can also be provided that, instead of the computationally determined first position, the last determined position is used to evaluate the calculated value. In this way an even greater accuracy can be achieved.
  • step S7 it is checked whether the position determination should be terminated, step S7. If this is not the case, the method is repeated from step S2 on.
  • the specific position may be output on the display means 10, for example. If a quality value has been determined, this is advantageously output together with the position. It may also be output if position measurements are discarded due to the "use-no-use" decision in step S5, thus also informing a user of the disturbance fields and their effects.

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  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Surgery (AREA)
  • Veterinary Medicine (AREA)
  • Public Health (AREA)
  • General Health & Medical Sciences (AREA)
  • Biomedical Technology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Medical Informatics (AREA)
  • Molecular Biology (AREA)
  • Animal Behavior & Ethology (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Robotics (AREA)
  • Pathology (AREA)
  • Physics & Mathematics (AREA)
  • Biophysics (AREA)
  • Human Computer Interaction (AREA)
  • Oral & Maxillofacial Surgery (AREA)
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Abstract

La présente invention concerne un procédé de détermination de position d'un instrument médical, notamment d'une capsule endoscopique, comprenant au moins trois bobines de réception orthogonales les unes aux autres et associées à un dispositif de détermination de position qui produit un champ magnétique de détermination de position variable dans l'espace au moyen d'éléments générateurs de champ. Au moins une bobine de référence fixe par rapport aux éléments générateurs de champ est utilisée. Le procédé de cette invention consiste à prendre des premières valeurs de mesure de référence de la bobine de référence lorsque le champ magnétique de détermination de position est activé, à prendre en continu et simultanément des valeurs de mesure de position des bobines de réception et des secondes valeurs de mesure de référence de la bobine de référence, afin de déterminer la position, à déterminer au moins une valeur de calcul décrivant un champ parasite possible à partir d'une comparaison des premières valeurs de mesure de référence et des secondes valeurs de mesure de référence, puis à déterminer la position en tenant compte de la valeur de calcul.
PCT/EP2008/052873 2007-03-14 2008-03-11 Procédé de détermination de position d'un instrument médical WO2008110553A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102007012361.4 2007-03-14
DE102007012361.4A DE102007012361B4 (de) 2007-03-14 2007-03-14 Verfahren zur Positionsbestimmung eines medizinischen Instruments und Positionsbestimmungsvorrichtung

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Publication Number Publication Date
WO2008110553A2 true WO2008110553A2 (fr) 2008-09-18
WO2008110553A3 WO2008110553A3 (fr) 2008-11-20

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WO (1) WO2008110553A2 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010149371A1 (fr) * 2009-06-26 2010-12-29 Fiagon Gmbh Procédé de production de données de position d'un instrument
US11357574B2 (en) 2013-10-31 2022-06-14 Intersect ENT International GmbH Surgical instrument and method for detecting the position of a surgical instrument
US11430139B2 (en) 2019-04-03 2022-08-30 Intersect ENT International GmbH Registration method and setup
US11944388B2 (en) 2018-09-28 2024-04-02 Covidien Lp Systems and methods for magnetic interference correction

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998049938A1 (fr) * 1997-05-08 1998-11-12 Lucent Medical Systems, Inc. Systeme et procede permettant de determiner la position et l'orientation d'un dispositif medical a demeure
WO2001033231A2 (fr) * 1999-11-01 2001-05-10 Polhemus Inc. Procede et appareil de poursuite electromagnetique de position et d'orientation incluant une correction de distorsion
US6618612B1 (en) * 1996-02-15 2003-09-09 Biosense, Inc. Independently positionable transducers for location system
WO2003086190A1 (fr) * 2002-04-10 2003-10-23 Stereotaxis, Inc. Systemes et procedes destines a des interventions medicales
WO2005082247A1 (fr) * 2004-02-18 2005-09-09 Philips Intellectual Property & Standards Gmbh Correction de valeurs mesurees pour un dispositif de localisation magnetique

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020103430A1 (en) * 2001-01-29 2002-08-01 Hastings Roger N. Catheter navigation within an MR imaging device
US7783441B2 (en) * 2003-04-17 2010-08-24 Northern Digital Inc. Eddy current detection and compensation
WO2004096042A1 (fr) * 2003-05-02 2004-11-11 Atropos Limited Systeme de surveillance de position

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6618612B1 (en) * 1996-02-15 2003-09-09 Biosense, Inc. Independently positionable transducers for location system
WO1998049938A1 (fr) * 1997-05-08 1998-11-12 Lucent Medical Systems, Inc. Systeme et procede permettant de determiner la position et l'orientation d'un dispositif medical a demeure
WO2001033231A2 (fr) * 1999-11-01 2001-05-10 Polhemus Inc. Procede et appareil de poursuite electromagnetique de position et d'orientation incluant une correction de distorsion
WO2003086190A1 (fr) * 2002-04-10 2003-10-23 Stereotaxis, Inc. Systemes et procedes destines a des interventions medicales
WO2005082247A1 (fr) * 2004-02-18 2005-09-09 Philips Intellectual Property & Standards Gmbh Correction de valeurs mesurees pour un dispositif de localisation magnetique

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010149371A1 (fr) * 2009-06-26 2010-12-29 Fiagon Gmbh Procédé de production de données de position d'un instrument
US9333047B2 (en) 2009-06-26 2016-05-10 Flagon GmbH Method for generating position data of an instrument
US11357574B2 (en) 2013-10-31 2022-06-14 Intersect ENT International GmbH Surgical instrument and method for detecting the position of a surgical instrument
US11944388B2 (en) 2018-09-28 2024-04-02 Covidien Lp Systems and methods for magnetic interference correction
US11430139B2 (en) 2019-04-03 2022-08-30 Intersect ENT International GmbH Registration method and setup

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Publication number Publication date
DE102007012361B4 (de) 2016-09-22
DE102007012361A1 (de) 2008-09-25
WO2008110553A3 (fr) 2008-11-20

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