WO1994024934A1

WO1994024934A1 - Device for endoscopical exploration of the body

Info

Publication number: WO1994024934A1
Application number: PCT/EP1994/001334
Authority: WO
Inventors: Andreas GRÜNDL; Alexander Bob; Konstantin Bob
Original assignee: Stm Medizintechnik Starnberg Gmbh
Priority date: 1993-04-27
Filing date: 1994-04-27
Publication date: 1994-11-10
Also published as: AU6649494A; DE4313843A1; DE4492659D2

Abstract

A device for endoscopically exploring the body has a support (4) upon which the body (24) to be explored may be placed and a coil device (14, 16) for generating a magnetic field having a first partial coil device (14) with a first axis (18) and a second partial coil device (16) with a second axis (20). The first and second axes lie at an angle and the energy supply to both partial coil arrangements is adjustable so that a magnetic field having the desired orientation is generated. The support (4) and the coil arrangement (14, 16) are movable with respect to each other in the three directions in space. An endoscopic probe (30) is equipped with a magnetically sensitive material (49, 50) so that it is orientated along the magnetic field and is subjected to a force in its longitudinal direction within the magnetic field. The support (4) and the coil arrangement (14, 16) can be rotated with respect to each other around an axis.

Description

DEVICE FOR ENDOSCOPIC EXPLORATION

OF THE BODY

The invention relates to a device for endoscopic exploration of the body, more precisely the human body or animal body.

Endoscopy is a branch of medicine that is becoming increasingly important. So far, endoscopic explorations have been carried out almost exclusively with endoscopes, which essentially consist of an elongated endoscope shaft and an endoscope head. The endoscope shaft is a semi-rigid, bendable structure, often with a diameter of 1 to 2.5 cm. The endoscope head contains a light source and either an optical system or a camera chip. The optical information acquired by means of the endoscope head is transmitted to the outside either by means of light guide cables or converted into electrical signals by an electrical conductor which run in the endoscope shaft. As a rule, the endoscope contains a bowden cable device with which the foremost area of the endoscope can be bent in several directions relative to the endoscope shaft. Finally, the endoscope shaft usually contains a working channel through which fluids can be conveyed to a fluid outlet in the area of the endoscope head and through which small medical "tools" can be used in the area in front of the endoscope head, e.g. Sampling tongs, needles, cutting wires for removing tissue, coagulation electrodes and the like.

Conventional endoscopes are moved into the body cavities by the doctor exerting pressure on the part of the endoscope shaft which protrudes from an insertion body opening. If a bend in an elongated body cavity has to be overcome, this can be facilitated by bending the foremost endoscope area in the corresponding direction. Overall, however, the introduction of conventional endoscopes is a laborious and time-consuming procedure,

SPARE BLADE (RULE 26) the space requirement of the endoscope shaft and its necessarily limited flexibility, in particular in the case of body channels with numerous and / or narrow bends, for example in the case of the intestine, represent very aggravating circumstances.

The invention has for its object to make available a device with which the endoscopic exploration of the body can be carried out much more easily, particularly in the case of body channels with narrow and / or numerous bends.

To achieve this object, the subject of the invention is a device for endoscopic exploration of the body, characterized by: a) a base on which the body to be explored can be placed; b) a coil device for generating a magnetic field, which has a first partial coil device with a first axis and a second partial coil device with a second axis, the first and second axes being at an angle to one another and the current supply to the two partial Coil devices can be adjusted so that a magnetic field of the desired orientation results; c) mobility of the base (4) and the coil device (14, 16) relative to one another in the three spatial directions; d) an endoscopic probe which is equipped with magnetically responsive material (48, 50) in such a way that it aligns itself along the magnetic field and experiences a force effect in its longitudinal direction in the magnetic field; and e) rotatability of the base (4) and the coil device (14, 16) relative to one another about an axis.

The device according to the invention is basically suitable for exploring all interiors of sufficient size of the body. Inner spaces which are particularly suitable are the trachea, the esophagus, the stomach, the intestine, the urinary tract to the kidney, the abdomen after air insufflation and large blood vessels up to and including the heart. The intestine is considered to be a very particularly preferred area of use, the pushing into the small intestine appearing possible due to the inventive design of the device.

SAW BLADE (RULE 26) The surface on which the body to be explored can be placed can be quite flat-table-like. For certain types of examination, however, a more chair-like surface can also be considered.

By means of the coil device designed in the above-mentioned manner in combination with the probe designed according to the invention, it is possible to change the orientation of the probe in the body in an electro-magnetic manner without mechanical movement or, in other words, the probe about a specific axis to turn. The exemplary embodiment to be described below will show that the two partial coil devices are usefully arranged in such a way that the axis of the probe about which it can be rotated electromagnetically is an axis of rotation which is particularly frequently required for the alignment of the probe.

The probe is preferably connected to at least one flexible strand which leads out of a body opening when the probe is inserted into the body. This strand can in particular be a safety line or an electrical line or a hose or can have at least one of these elements. The flexible strand, which consists of only one such element or several such elements, is preferably considerably thinner and more flexible than a conventional endoscope shaft, which avoids difficulties of the type described above when inserting the probe in comparison to inserting a conventional endoscope or at least significantly reduced.

The probe preferably contains a transmitter for transmitting data, in particular image data obtained, to the outside. An alternative which is also possible within the scope of the invention consists in that the image information is transmitted to the outside via the above-mentioned electrical conductor which forms the strand or is part of the strand. The version with the transmitter has the advantage that an electrical conductor connection to the probe is unnecessary in many cases, because e.g. can supply the light source, the camera chip and the transmitter in the probe with power via a battery or an accumulator. The safety line mentioned earlier in connection with the strand is merely a precautionary one

TZBLAH (RULE 26) Measure to be able to pull the probe out of the body again by means of this line if necessary. The safety line can also be dispensed with, particularly in the case of probes which are intended to examine less problematic body cavities than the intestine, since the probe can be moved back out of the body using the same mechanisms as those introduced forwards.

The probe preferably contains a space for accommodating a strand supply such that strand length can be continuously released from this supply while the probe moves ever further into the body. In this way, the probe does not have to follow a possibly quite long strand length around possibly numerous bends behind it. The alternative embodiment, that only the front end of the strand is attached to the probe and that the probe pulls the strand when it is moved into the body, is also possible.

Moving the probe into the body, especially along the elongated body channel to be explored, e.g. of the intestine, is done in practice so that the probe and the body are moved relative to each other in such a way that the probe progresses along the body channel. The movements in the three spatial directions or the movement in a translational direction, which is composed of one, two or three spatial directions, takes place through the relative mobility of the base and the coil device, which, as it were, holds the probe in itself. The inventive rotation of the probe about two axes is carried out electromagnetically by the coil device and by physical rotation of the coil device about an axis. It is not necessary to rotate the probe about the third conceivable spatial axis because this coincides with the longitudinal axis of the probe.

In the most general case, performing the required relative movement between the probe and the body to be explored requires a translational displacement in the three spatial directions, an electrical-magnetic rotation about an axis and a rotation of the coil device. For this purpose, the device can have five command transmitters, one for each of the shifts and rotations mentioned. The physician performing the exploration either sequentially or partially simultaneously operates these five commanders so that the probe travels along of the body channel located in front of the probe, staying in its center as far as possible to some extent. It is pointed out that if the probe is aligned to some extent exactly with the longitudinal direction of the body channel and if the body channel has a somewhat rectilinear section, this movement is a pure translational movement with a maximum of three components. If a bend in the body channel has to be mastered, either a pure rotary movement around a maximum of two axes or a rotary movement combined with a certain translational movement must be carried out.

In particular, the described movement of the probe along a straight section of the body channel can be easily automated. From the orientation of the magnetic field of the coil device (which results from the size of the current leads to the two partial coil devices), the device “knows” how the probe is aligned in accordance with the magnetic field. From this, an electronic computer can easily calculate the required movement components in the three spatial directions, which the support and the coil device must perform relative to one another so that the probe moves along the straight section.

Furthermore, an even more automated control is possible, in which the image information acquired by the probe about the progress of the body channel in front of it is converted into control information for the movements and the electro-magnetic adjustment or adjustment of the coil device of the device leaves. In the case of intestinal exploration, the optical system or the camera chip of the probe perceives an essentially symmetrical image of a circle, the brightness of which decreases from the outside to the inside, provided that the probe is aligned longitudinally in the intestine approximately at its center. The control of the movements and the coil currents can be programmed in such a way that the five components of the movement mentioned take place in combination in such a way that the probe moves forward while maintaining this image perception as far as possible.

It is pointed out that the device according to the invention also for exploring the cavities or channels of technical products, e.g. the internal investigation of heat exchangers with complicated fluid channel structures.

SPARE BLADE (RULE 26) The tube mentioned earlier in connection with the strand can in particular be used to eject a gas on the probe, for example for locally filling the intestine with gas. If necessary, a flushing liquid can also be injected through the tube against the intestinal wall.

The safety line mentioned above can also be used as a guide line, which - pulled through the working channel of a conventional endoscope - makes it easier to insert it along the body channel. This endoscope can then be used to carry out any necessary medical interventions. It is expressly pointed out that the above-described endoscopic probe in combination with an arbitrarily designed coil device for magnetically “holding” or moving the probe is regarded as a separate invention. In this invention, the two partial coil devices with intersecting axes do not necessarily have to be present.

The invention and embodiments of the invention are explained in more detail below with the aid of schematically illustrated exemplary embodiments. It shows:

1 shows a top view of a device according to the invention, illustrated in the example of endoscopic exploration of the intestine;

Fig. 2 shows the device of Fig.l in side view;

3 shows the probe provided in the device according to FIG. 1 on a substantially enlarged scale, in longitudinal section;

Fig. 4 is a block diagram of a highly computerized control ^device .

The endoscopy device 2 shown in FIGS. 1 and 2 has a table-like, horizontal base 4. The base 4 is supported by a flat-wagon-like base 6, namely by means of a height-adjustable column 8 at the head end of the base 4. The base 4 can be moved horizontally at its head end in a direction perpendicular to the longitudinal direction of the base 4. On the top of the base 6, a carriage 10 movable in the longitudinal direction of the base 4 is attached. The carriage 10 carries on its upper side a large, hollow cylindrical tube 12 with an inner diameter of approximately 1 m, the longitudinal axis of the tube 12 extending horizontally in the longitudinal direction of the base 4.

A first partial coil device 14 and a second partial coil device 16 are fastened to the inside of the tube 12. The first partial coil device 14 has an axis 18, and the second partial coil device 16 has an axis 20. The two coil axes 18, 20 run at right angles to one another in the exemplary embodiment shown and intersect at a point 22 somewhat above the upper side the base 4, the position of a patient 24 being positioned approximately at the point 22 in an endoscopic intestinal examination. The two partial coil devices 14, 16 surround the base 4 with the patient lying thereon in a ring.

ERSÄΓZBLAΓT (RULE 26) Each of the partial coil devices 14, 16 consists of a coil, but can also consist of several coils placed axially next to one another. An axially directed magnetic field is generated in the interior of each partial coil device 14 or 16 when current is supplied.

Axis 18 or 20 of the respective partial coil device 14 or 16 denotes the straight line which coincides with the central cylinder axis in the case of a cylindrical partial coil device. If one imagines a partial coil device with an elliptical frontal view in the front view, it is the axis which passes through the center of the ellipse and which is perpendicular to the plane of the ellipse.

The two sub-coil devices 14, 16 together form the overall coil device for generating a magnetic field. In the side view of FIG. 2, the two partial coil devices 14, 16 optically coincide. Each partial coil device 14, 16 is circular in the illustrated embodiment in frontal view, so that it does not lie along its entire circumference on the inside of the tube 12 because of the inclination of the axes 18, 20 relative to the longitudinal axis of the base 4. In the embodiment shown, each of the axes 18, 20 extends at an angle of 45 ° relative to the longitudinal central axis 26 of the base 4. The partial coil devices 14, 16 can also be elliptical.

If both partial coil devices 14, 16 - assuming the same winding structure - current of the same current strength is supplied, a common magnetic field is created, the direction of the magnetic field lines being parallel to the longitudinal axis 26 of the base 4. As the current through, for example, the second sub-coil device 16 is reduced and the current through the first sub-coil device 14 is increased to compensate, the direction of the magnetic field lines rotates away from the axis 26 in the direction more towards the first Axis 18 of the first partial coil device 14, and vice versa. It is good if the currents through the two partial coil devices 14, 16 are always adjusted so that the strength of the magnetic field is always the same regardless of the orientation of the magnetic field. With the described arrangement of the partial coil devices 14, 16 and the described type of power supply to these, one thus has an instrument that Alignment of the magnetic field through 360 ° (possibility of reversing the direction of current flow through the coils is taken into account) about an axis which extends at right angles to the axes 18, 20 through their intersection 22.

The tube 12, which serves as a holder for the partial coil devices 14, 16, can be rotated through 360 ° with a horizontal axis of rotation relative to the slide 10 and thus relative to the base 4 as a result of a bearing 28.

To simplify the further description, it is assumed that a probe to be described in more detail later is located at the interface 22 of the axes 18, 20, specifically in the direction of the first axis 18 of the first partial coil device 14. The endoscopy device described thus has 2 three translational possibilities of the relative movement between the patient 24 and the coil device, namely longitudinally horizontally by means of the slide 10, vertically by means of the column 8 and transversely horizontally by means of the base 4 relative to the column 8, and the rotational possibility of the Probe relative to the patient 24 by rotating the tube 12 about the horizontal longitudinal axis, and the rotational orientation of the probe relative to the patient 24 about the described axis of rotation, which is perpendicular to the axes 18, 20, by adjusting one different ratio of the currents through the first partial coil device 14 and the second partial coil device 16.

3, the probe 30 already mentioned is shown in more detail. Overall, the probe 30 has the configuration of an elongated circular cylinder with a rounded front end 32 and a rounded rear end 34. The front end 32 is transparent, and a lens or a lens system and a light source, designated 36 in common, are arranged on the inside thereof. On the back of the lens is a camera chip 38. On the back of the camera chip 38 is a camera electronics 40. Further on the back of the camera electronics 40 is a module 42 which contains a transmitter and a power supply. The remaining interior of the probe 30 is formed by a receiving space 44 for a strand 46, in the present example a safety line.

ERSÄΓZBLÄΓT (RULE 26) Subsequent to the rounded front area 32, a hollow cylindrical permanent magnet 48 is provided on the outside of the probe 30, the longitudinal axis of which coincides with the longitudinal axis of the probe 30. The permanent magnet 48 has, for example, a north pole on its front, circular end face and on its rear, circular one

Face of a south pole. The permanent magnet 48 takes up about a quarter of the length of the probe 30. Subsequent to the rear end face of the permanent magnet 48, a hollow cylindrical soft iron part 50 is provided, which takes up about half the length of the probe 30. The strand 46 is loosely inserted in a suitable manner in the storage space 44, so that the strand 46 is gradually pulled out of the storage space 44 to the extent that the probe 30 moves into the intestine of the patient 24. ,,.

Due to the described equipment of the probe 30 with the

Permanent magnets 48 and the soft iron part 50 always align the probe 30 with its longitudinal axis in accordance with the direction of the magnetic field of the coil device described further above. Since the magnetic field lines at the axial ends of the coil device bend radially outward, the probe 30 is magnetically held in the axial central region of the coil device and is prevented from coming out at the axial ends of the coil device. The permanent magnet 48 is not absolutely necessary.

The described inclusion effect of the probe 30 in the

Coil device can be further enhanced by placing a further coil on each axial side of each partial coil device 14, 16, which coil flows through in operation with the opposite direction of current as the central coil. This increases the gradient of the magnetic field strength at the axial ends of the central coil.

A control device 52 and a receiver / monitor 54 are also shown in FIG. 1.

The doctor who endoscopically explores the intestine of the patient 24, after inserting the probe 30 into the anus of the patient 24, proceeds in such a way that he transmits the image to the outside by means of the described transmitter the intestinal section in front of the probe front area 32 observed on the monitor 54. On the control unit 52 he operates control buttons 56 in order to move the patient 24 or the tube 52 holding the coil device in a combination of linear movements in the three spatial directions in such a way that the probe 30 (which is caused by the

Magnetic field of the coil device "tied up" remains stationary or essentially stationary at the interface 22) along the intestinal section of the patient located in front of the probe 30 relative to the latter. If a bowel bow has to be overcome, the doctor must use other of the control buttons 56 to rotate the support tube 12 about its longitudinal axis and / or change the ratio of the currents through the partial coil devices 14, 16 so that the probe 30 changes in the direction of the subsequent section of the intestine. It goes without saying that the three translational movement components and the one rotational rotation are carried out with external force, for example with the aid of electric motors.

The three translational movement options and the one rotational movement option can be divided as desired between the base 4 and the coil device 14, 16. For example, make the table 10 longitudinally, transversely and vertically. Or one could make the base 4 rotatable about the longitudinal axis 26 instead of the coil device 14, 16.

The probe 30 can include a sampling forceps that can be extended upon command and can pinch a tissue sample from the intestinal wall.

FIG. 4 is a block diagram of a highly computerized control device, generally designated 60.

For easier understanding, the control device 60 is initially described as if it only contains the following structural units: coil system 62 (consisting of the first partial coil device 14, the second partial coil device 16 and the partial Coil devices 14, 16 carrying tube 12) which can be rotated about its longitudinal axis, coil / table driver 64 with computer, manually operated movement lever 66 and specification unit 68. In addition, the camera 38 in the probe 30 and the monitor 54. Furthermore, to facilitate the Understanding first assumed that the probe 30 at

Moving into the intestine does not rotate around its own longitudinal axis, e.g. the bottom of the probe 30 pointing downward when the probe is initially inserted, even after covering a certain movement distance in the intestine, still forms the bottom of the probe 30 pointing downward.

With the movement lever 66, the doctor operating the device can carry out the commands “forward” or “backward” (in the direction of the longitudinal axis of the probe), “front probe end more to the left” or “front probe end more to the right”, and “front probe end more upwards” or "Front probe end down more". These commands are given to the driver 64 in electrical form via the specification unit 68. The driver 64 is in feedback connection with the coil system 62 and therefore "knows" before the receipt of a new command due to the currents through the component

Coil devices 14, 16 and due to the previous rotational position of the tube 12, which position in space has the longitudinal axis of the probe 30. When a command "forward" or "backward" is given with the movement lever 66 (because, as the doctor sees on the monitor 54, the longitudinal axis of the probe with the one to be traversed

Intestine section is aligned), the computer of the driver 64 calculates which combination of movements of the support 4 translates into the three available movement directions and with which superimposition of three movement speeds in these three directions the commanded movement can be carried out and controls the movement drives of the support 4 accordingly.

When a "probe left end" or "probe right end" command is given, the driver 64 computer calculates how this command changes the currents through the part-

Coil devices 14, 16 and / or rotation of the tube 12 about its The longitudinal axis must be implemented and controls the execution of the command accordingly. The execution of the commands "front end of probe more up" or "front end of probe more down" is carried out in a similar manner.

The intestinal area in front of the probe 30 is observed while the probe 30 is being moved in and / or out of the intestine. The image obtained by means of the camera 38 is made visible to the doctor on the monitor 54. The units 78 and 80 shown in FIG. 4 on the transmission path from the camera 38 to the monitor 54 are not present in the control device 60 of the highest computerization level described so far. It is emphasized, however, that the control device 60 in the configuration described so far represents a fully functional control device.

The controller 60 will now be described in the highest level of computerization. The essential additional function is that a gravity sensor 70 is additionally installed in the probe 30. Gravity sensors are commercially available and work e.g. with a weight and electrical recording of the holding forces of the weight divided according to the three spatial directions. The gravity sensor 70 is used to determine whether and by what angle the probe 30 has possibly rotated about its longitudinal axis. Based on this information, the image of the

Monitor 54 rotated so that the commands "front end of probe more to the left", "front end of probe more to the right", "front end of probe more up", and "front end of probe more down" actually result in the same sense on the monitor 54 reflect.

For this purpose, the output signals of the gravity sensor 70 are given to a computing unit "rotation angle" 72, which determines the rotation angle of the camera 38 relative to the gravity axis from the measured gravity components. The computing unit

"Room vector" 74 is connected to the driver 64 and is determined from the driver signals for the partial coil devices 14, 16 and for the rotational position of the tube 12, a space vector under which the probe 30 is located. The information from the units 72 and 74 are combined in a coordinate generator 76, where a rotation matrix for the video image is generated.

The output signals of the camera 38 are given to a "video" unit 78, put together there to form an electrical video image and given to a "picture rotation" unit 80, where the output information of the coordinate generator 76 is also given. The

The "image rotation" unit 80 then controls the monitor 54 so that the image is displayed in the desired "correct" rotation orientation.

In an even higher level of computerization, the output information of the "image rotation" unit 80 is additionally reduced to one

Unit "symmetry evaluation" 82 given, which in turn is connected to the default unit 68 described above. Now - apart from the commands "forward" and "backward" - fully automatic movement of the probe 30 along the intestine is possible. The "symmetry evaluation" unit 82 also gives the driver 64 the

Information whether the probe 30 has its longitudinal axis properly aligned with the longitudinal axis of the section of intestine to be passed, e.g. due to the light / dark circular symmetry of the image recorded by the camera 38. In the event of a deviation from the desired symmetry, appropriate commands are given to the driver 64 for realigning the spatial position of the longitudinal axis of the probe.

The reference numeral 84 denotes an infogenerator which can, but need not, be provided to increase the working comfort. The infogenerator 84 is connected to an output of the specification unit 68 and outputs its output signals to the monitor unit 54. The spatial position of the probe 30 can thus be spatially displayed on the monitor 54, which improves the overview of the examining doctor. Finally, it should be pointed out that components 70, 72, 74, 76, 78, 80, 82 are alternatively omitted and replaced by a manual-electrical correction unit connected to driver 64 to take account of the momentary rotation of probe 30 about its longitudinal axis can. If, for example, the examining doctor determines that a command "front probe end more to the left" leads through the movement lever 66 to a command execution in which the front probe end moves diagonally to the top right, then he can adjust with the correction unit until command and Order execution are again in the suit. Since the probe 30 rotates only slowly and normally not through large angular amounts about its longitudinal axis during its movement along the intestine, such a correction from time to time does not constitute a significant difficulty in operating the device.

Claims

1. Device for endoscopic exploration of the body, characterized by: a) a base (4) on which the body (24) to be explored can be placed; b) a coil device (14, 16) for generating a magnetic field, the first partial coil device (14) with a first axis (18) and a second partial coil device (16) with a second axis (20) has, the first and second axes being at an angle to one another and the power supply to the two partial coil devices being adjustable such that a magnetic field results in the desired orientation; c) movability of the base (4) and the coil device (14, 16) relative to one another in the three spatial directions; d) an endoscopic probe (30) which is equipped with magnetically responsive material (48, 50) in such a way that it is aligned along the magnetic field and experiences a force effect in its longitudinal direction in the magnetic field; and e) rotatability of the base (4) and the coil device (14, 16) relative to one another about an axis.

2. Device according to claim 1, characterized in that the probe (30) is connected to at least one flexible strand (46) which leads out of a body when the probe (30) is inserted.

3. Apparatus according to claim 2, characterized in that the strand (46) is a safety line or an electrical line or a hose or has at least one of these elements.

4. Apparatus according to claim 2 or 3, characterized in that the probe (30) contains a space (44) for accommodating a strand supply in a continuously extractable manner.

5. The device according to at least one of claims 1 to 4, characterized in that the probe (30) has a transmitter (42) for transmitting data to the outside.

6. The device according to at least one of claims 1 to 5, characterized by a control device (52) with which a command "forward movement probe de" can be implemented in an axis-combined relative movement of the base (4) and coil device.