DE102007051860A1 - Magnetically controlled capsule endoscope equipment operating method for determining existence of e.g. electrically conducting body, involves providing information message for deviation of two null position measurements beyond measurement - Google Patents

Abstract

The method involves executing two null position measurements with switched off navigation coils (2) to execute a position measurement to a measurement object in which no endoscope capsule is inserted. The null position measurements are compared with each other. An information message i.e. warning, is provided for each deviation of the two null position measurements beyond a measurement, where the null position measurements of the measurement object are executed at different regions of the measurement object. An independent claim is also included for a magnetically controlled capsule endoscope equipment comprising navigation coils.

Description

The The invention relates to a magnetically-guided capsule endoscopy (MGCE) device and a method of operating the same.

The The present invention relates to an MGCE device a navigation coil system that (similar to a magnetic resonance imaging (MRI) device) is preferably tubular, wherein a measurement object, for. B. a patient on a horizontally movable Liege pushed into the tube and inside the tube at least axially can be pushed back and forth. Inside the navigation tube there is another tube in the MGCE device, which is equipped with transmitting and receiving coils and the Enclosing patients, and those of the electromagnetic position measurement of the patient swallowed or rectally inserted serves magnetic capsule endoscope.

A possible position measuring principle of the endoscope capsule is in WO 2005/120345 A2 described. The position measurement principle provides that the receiving coils measure the alternating electromagnetic field transmitted by the transmitting coils (with a frequency between 500 Hz and 50 kHz), whereby the 5D position (= 3D center of gravity coordinates + 2D orientation vector of the LC marker coil in the capsule endoscope ) is determined from the difference of the measuring signal vector with capsule endoscope in the working volume and the measuring signal vector without capsule endoscope (= empty measurement). The working volume, in which a reliable position measurement can be carried out, has a length of 15 cm to 60 cm, so it is shorter than the MGCE magnet (about 80 cm to 140 cm) or the patient from head to buttocks. The measuring signal vector of a blank measurement is relatively sensitive to the presence of electrically conductive foreign bodies, in particular if they are in the vicinity of the transmitting and receiving coils, ie in particular in the working volume. The Amperewin tion number and thus field strength of the transmitter coils of the position measuring system is very low compared to the ampere-turn number and field strength of the (powered by rated current) navigation coils. Therefore, operation of the position transmitter coils on the patient, which still has electrically conductive foreign bodies in or on itself, is harmless, whereas this is not generally true for the operation of the navigation coils.

Similar as with the MRI must be found out before an MGCE, and if possible be excluded, whether in or on a test object, eg. As a patient, electrically conductive foreign body (in particular Metal parts and ferromagnetic materials). Examples for such foreign bodies are (in the patient) cardiac pacemaker, Shrapnel (from war wounds), vascular clips and / or (on patients) jewelery (piercing), clothing and clothing accessories (belt buckles, ballpoint pens) and medical devices (insulin or analgesic pumps).

It However, there are differences between MRI and MGCE: so are magnetic DC basic fields at MGCE by at least one order of magnitude less than the MRI (maximum several 100 mT compared to several Tesla), since there are no superconducting basic field magnets in the MGCE gives. In addition, alternating magnetic fields in the MGCE are clear lower frequency than in MRI. Consequently, at small electric conductive foreign bodies (such as small clips) an MGCE possibly nevertheless be carried out.

One additional problem with the MGCE is, however, that the position measurement of the endoscope capsule in the body as well electromagnetically and electrically conductive foreign body can significantly disturb this (sensitive) measurement, in particular if the geometry and location of the foreign body or not exactly known in advance.

at The MRI will be an informative meeting before the examination with the patient, the u. a. the goal is to clarify and Exclude that electrically conductive foreign body on or in the patient. As a possible MRT / MGCE clientele includes older patients, the z. T. forgetful or are even demented, is a safe exclusion based on the patient statement almost impossible. As a supplement can old information about the course of the disease or surgical reports be used. But this costs time and further assumes that is known where the patient previously treated everywhere has been.

It is thus the object of the present invention, a possibility for the safe yet comparatively simple determination of a Presence of electrically conductive body on a means to provide a measured object to be measured by MGCE.

These Task is by means of a method according to claim 1 and a MGCE device according to claim 9 solved

The method is used to operate an MGCE device with navigation coils and a position measuring system for an endoscope capsule. It has (at least) the following steps:
Performing at least two empty position measurements with deactivated navigation coils, of which at least one on a measurement object, in the no endoscope capsule is inserted is performed.

to compare the empty position measurements. This can be done by any known Methods happen, for. B. by comparing a height signal peaks or a comparison of integrated signal intensities, for example, for only one defined signal peak or a spectrum range.

Output a first note - z. B. a warning - at Deviation of the at least two empty position measurements via a first degree. As a measure can For example, a predetermined threshold or threshold value relationships be used. For example, the first measure may be up an electrically conductive object point its whereabouts in the object to be measured damage the object to be measured by the following MGCE measurement using the navigation magnetic coils can not be excluded.

By This process can certainly be a significantly more electrically conductive Object or an electrically conductive object more significant Size to be detected on the measurement object, namely on a way that is harmless to human health and without much additional time or staffing Effort.

It is preferred if the method further comprises the following step comprising: issuing a second message in case of deviation of the at least two empty position measurements over a second Measure, which is less than the first measure. If the deviation in other words between the first and the second measure, another message is issued. For example, the range between the first measure and the second (lower) dimension to an electrically conductive Point out object, while remaining in the test object while no Damage to the DUT by the following MGCE measurement is expected with the use of navigation magnetic coils, the measurement sensitivity but is reduced.

Preferably the empty position measurements on the measurement object become different Areas of the test object carried out, as well as measurement objects to be able to feel larger than the typical one Work area of the MGCE device.

Around to leave no unrecognized areas, it is advantageous if adjacent areas of the empty position measurements overlap on the measurement object.

It is further preferred for increasing the measurement accuracy, if in deviation between the first measure and the second Measure for a particular range a re-calibration the position measurement for this area becomes. Then a more accurate MGCE measurement can be followed.

It is further preferred, if at a deviation for a certain area at least beyond the second level for this area whose position is output. In In other words, this area (or area) is considered to be one Area (or areas) identified in which (or those) themselves an electrically conductive object corresponding to the respective one Note, and the position / location of this area (these areas) is output. This can be a search and identification of the object (s).

It may be advantageous if the comparing step is a comparison of empty position measurements made on the measurement object has one another. In other words, the identification electrically conductive objects by a comparison between measurements reached at the measuring object. This can be z. B. a deviation between smallest and largest values of the group of measurements or a deviation from a mean u. v. m.

It may alternatively or additionally be advantageous, if the comparing step comprises comparing empty position measurements made on the measurement object with a reference empty position measurement not performed on the measurement object having. In particular, the case can be caught that all or most of the blank measurements on the test object in the presence of a electrically conductive object performed in the respective measuring range become.

The Task is also carried out by an MGCE device solved a method above, the turn-off coils for magnetic capsule navigation and a control device, the is set up to run the procedure has.

Prefers becomes an MGCE device, in which the coils to the magnetic Capsule navigation as over power amplifier controlled normal-conducting coils are formed.

The Invention will become schematic in the following embodiments described in more detail.

1 sketchily shows a structure of an MGCE device;

2 shows a flowchart for operating an MGCE device.

1 shows a structure of an MGCE device 1 for endoscope control with a normal conducting capsule navigation magnet 2 for magnetic guidance or navigation of an endoscope capsule. The capsule navigation magnet 2 is for operation with power amplifiers 3 and a cooling system 4 connected. In this embodiment, the coil current is in all navigation coils 2 (completely) switched off, z. B. according to DE 103 40 925 B3 ,

The cooling system 4 and the capsule navigation magnet 2 are also equipped with a temperature monitoring system for temperature monitoring 5 connected. With the capsule navigation magnet 2 also connected are a transmitter / receiver 8th a position measuring system and an image data receiver 9 and optionally a magnetic field measuring unit 6 and a patient table control unit 7 ,

The central control unit is a capsule navigation magnet control unit 10 , The capsule navigation magnet controller 10 is connected to the power amplifiers via digital and / or analog data interfaces 3 , the temperature monitoring system 5 , with the magnetic field measuring unit 6 , with the patient table control unit 7 , with the transmitter / receiver 8th of the position measuring system via a position measuring control unit 15 as well as with the image data receiver 9 as well as the image processing and display unit 18 , The capsule navigation magnet controller 10 is further provided with a central data storage unit 20 as well as with a graphical user interface 22 coupled. The capsule navigation magnet controller 10 also has an input unit 24 on or is coupled with this.

2 FIG. 12 shows a flow chart for operating an MGCE device prior to the actual MGCE procedure, ie, prior to the introduction of an endoscope capsule and subsequent magnetic capsule navigation.

In In a first step S1, a patient (the measurement object) sets himself up the patient couch, without the capsule endoscope either orally or rectally already have been introduced. They are all navigation coils switched off, d. they do not generate a magnetic field.

In In a second step S2, the patient is removed from the patient automatically once from head to buttocks, better still up to the foot, driven through the MGCE magnet (at continue switched off navigation coils). It will take a series of empty position measurements carried out. Each empty position measurement mainly covers one Longitudinal section of about the length of o. G. workload from. Empty position measurements are made at such (axial) distances performed that they overlap.

In a third step S3, the individual empty position measurements compared to each other.

distinguish the empty position measurements are very clearly separated from each other the deviations above a predetermined first level), Thus, in step S4, the MGCE device issues a warning or a first note (eg "electrically conductive foreign bodies Found ") that on or in the patient one or more larger electrically conductive foreign bodies are located.

If it is a single, spatially not too large Foreign body acts, can be determined by the strength of the Deviation of the individual empty measurements in an additional one Step (without reference numeral) are given in addition, at which axial position of the patient, the foreign body in is about.

at sufficiently good match of the empty position measurements the MGCE device gives each other, now in step again S4, a corresponding note (eg "no electrical conductive foreign body found ") or no indication.

optional If necessary, a second message can be output in step S5 the empty position measurements are significant, but not very strong among each other or from a previously made reference blank measurement. Then the MGCE device automatically detects a small, but not endangering the patient electrically conductive Foreign body.

To a warning message (eg "small electrically conductive Foreign body found ") and possibly an acknowledgment / release by the medical operating personnel, the position measuring unit with the help of empty measurements in another optional step S6 will be automatically re-calibrated to despite Presence of one or more small electrically conductive Foreign body sufficiently accurate to work.

Preferably will after checking for electrical conductive Body and after insertion of the capsule endoscope the patient bed for the beginning of the magnetic capsule navigation moved to the starting position, and then or simultaneously the navigation coils are energized.

Of course the invention is not limited to the described embodiments limited.

Thus, in step S3, the individual Empty position measurements can be compared alternatively or additionally with a reference empty measurement previously performed without a measurement object or patient.

In Step S4 and S5 can then use the different clues depending on whether the empty position measurements differ from the reference empty measurement.

Of course the present invention is not for tubular MGCE systems limited. It is also conceivable that the Navigation magnet coils completely below the patient bed are arranged. The patient bed may then possibly not just one-dimensional (in the patient's longitudinal direction), but two-dimensional (ie additionally also transversely to the patient's longitudinal axis) be displaceable. Alternatively, the navigation solenoids be mounted below and above the patient bed with a lateral opening as in an open MR system (z. B. Siemens Magnetom C!).

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• WO 2005/120345 A2 [0003]
• - DE 10340925 B3 [0026]

Claims (10)

Method (S1-S6) for operating an MGCE device ( 1 ) with navigation coils ( 2 ) and a position measuring system ( 8th ) for an endoscope capsule, comprising the following steps: - performing (S2) at least two empty position measurements with deactivated navigation coils ( 2 ), at least one of which is performed on a measurement object into which no endoscope capsule is inserted; - comparing (S3) the empty position measurements, - outputting (S4) a first indication message if the at least two empty position measurements deviate beyond a first measure. The method of claim 1, further comprising Step: - output (S5) a second message in case of deviation of at least two empty position measurements on a second measure that is less than the first Measure. Method according to claim 1 or 2, wherein the empty position measurements performed on the DUT at different areas of the DUT become. The method of claim 3, wherein adjacent ones Regions of the empty position measurements on the measurement object overlap. A method according to claim 3 or 4 in combination with Claim 2, wherein in case of deviation between the first measure and the second measure for a particular area Re-calibration (S6) of the position measurement for this area is carried out. Method according to one of claims 3 to 5, where at a deviation for a certain range at least beyond the second level for this Area whose position is output. Method according to one of the preceding claims Claims in which the comparison step (S3) comprises: - To compare of empty position measurements made on the measurement object among themselves. Method according to one of the preceding claims Claims in which the comparison step comprises: - To compare of empty position measurements made on the measurement object with a reference empty position measurement not performed on the measurement object. MGCE device ( 1 ) for carrying out a method according to one of the preceding claims, comprising turn-off coils ( 2 ) for magnetic capsule navigation and a controller adapted to run the method (S1-S6). MGCE device ( 1 ) according to claim 9, wherein the coils ( 2 ) for magnetic capsule navigation than via power amplifiers ( 3 ) are driven normally conducting coils.