CN113037042B

CN113037042B - Capsule endoscope's magnetic control biopsy mechanism

Info

Publication number: CN113037042B
Application number: CN202110382618.9A
Authority: CN
Inventors: 宋霜; 武晓阳; 王焦乐; 张硕; 孟庆虎
Original assignee: Shenzhen Graduate School Harbin Institute of Technology
Current assignee: Shenzhen Graduate School Harbin Institute of Technology
Priority date: 2021-04-09
Filing date: 2021-04-09
Publication date: 2022-05-03
Anticipated expiration: 2041-04-09
Also published as: CN113037042A

Abstract

The invention provides a magnetic control biopsy mechanism of a capsule endoscope, which comprises a fixed base, a stator permanent magnet, a biopsy working head, a rotor permanent magnet, a movable base and a protective shell, wherein the fixed base, the stator permanent magnet, the biopsy working head, the rotor permanent magnet and the movable base are all positioned in the protective shell, and the fixed base is fixed outside the capsule endoscope. The invention has the beneficial effects that: the magnetic control biopsy mechanism provided by the invention is externally arranged on the surface of the magnetic drive capsule endoscope, has a simple structure, is easy to assemble and disassemble, does not need to change the existing structure, and increases the sampling function; the driving energy is remotely provided by an external magnetic field, a built-in battery is not needed, and the damage to a human body is reduced; the device can repeatedly perform sampling biopsy operation by applying an external magnetic field for multiple times, so that the sampling success rate is improved; the biopsy working head axially extends out, the sampling range is enlarged, a camera positioned at the head of the capsule is easy to be matched with an external magnetic field, and the sampling process is better observed.

Description

Capsule endoscope's magnetic control biopsy mechanism

Technical Field

The invention relates to a capsule endoscope, in particular to a magnetic control biopsy mechanism of the capsule endoscope.

Background

The capsule endoscope is a revolutionary innovation for gastrointestinal tract disease examination and endoscope development, and compared with the traditional endoscopy, the capsule endoscope not only has the characteristics of painless and noninvasive comfortable endoscopy, but also has extremely high examination accuracy. The method is basically characterized in that a micro-camera is used for wirelessly transmitting an inspection image to realize the functions of sampling, pesticide application and the like. The capsule endoscope with biopsy function is one of the key technologies for effectively applying the capsule in clinical practice.

The existing endoscope capsule with biopsy function can be divided into external control and internal control, wherein the internal control is mainly driven by shape memory alloy, a torsion spring and a miniature clamp, and the biopsy driving devices have complicated structures, high energy supply requirements and are not capable of repeatedly sampling. The external control is mainly in a magnetic control mode, is basically integrated in the capsule endoscope as a biopsy module, occupies a large amount of internal space, and is not strong in replaceability and small in sampling range. These problems have hindered the widespread use of sampling modules in the field of capsule endoscopic robotics.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a magnetic control biopsy mechanism of a capsule endoscope, which can be arranged on the outer surface of the capsule endoscope, can increase the biopsy function under the condition of not changing the internal structure of the existing capsule and is convenient to assemble and disassemble.

The invention provides a magnetic control biopsy mechanism of a capsule endoscope, which comprises a fixed base, a stator permanent magnet, a biopsy working head, a rotor permanent magnet, a movable base and a protective shell, wherein the fixed base, the stator permanent magnet, the biopsy working head, the rotor permanent magnet and the movable base are all positioned in the protective shell, the fixed base is fixed outside the capsule endoscope, the stator permanent magnet is fixed on the fixed base, the rotor permanent magnet is fixed on the movable base, the rear end of the biopsy working head is fixed on the movable base, the front end of the biopsy working head is in guide fit with the fixed base, after an external magnetic field is applied, the rotor permanent magnet and the movable base synchronously move along the axial direction, so that the biopsy working head fixedly connected on the movable base extends out of the fixed base at the front end to perform sampling biopsy operation, after the external magnetic field is removed, the stator permanent magnet repels the rotor permanent magnet, so that the biopsy working head is recovered and reset.

As a further improvement of the invention, the external driving mode of the capsule endoscope is magnetic driving, and the external driving mode is specifically electromagnetic driving and permanent magnetic driving according to the mode of applying an external magnetic field. The head material is transparent, and the camera is equipped with to the head to the collection of carrying out the image, observe the sampling process.

As a further improvement of the invention, the fixed base is annular, the shell of the capsule endoscope is cylindrical, the fixed base and the shell of the capsule endoscope are in interference fit, and the fixed base is fixed on the outer surface of the shell of the capsule endoscope.

In a further improvement of the present invention, the movable base is annular, and the movable base is slidably fitted to an outer surface of the housing of the capsule endoscope.

As a further improvement of the invention, the fixed base, the stator permanent magnet, the rotor permanent magnet, the movable base, the protective shell and the shell of the capsule endoscope are coaxially arranged.

As a further improvement of the invention, the fixed base is provided with a guide through hole which is axially arranged, and the front end of the biopsy working head is arranged on the guide through hole in a penetrating way.

As a further improvement of the invention, the stator permanent magnet and the rotor permanent magnet are both axially magnetized annular permanent magnets, and the stator permanent magnet and the rotor permanent magnet repel each other in an initial state.

As a further improvement of the present invention, the stator permanent magnet and the mover permanent magnet should be made of the same material, have the same size, and are placed opposite to each other in an initial state, and the permanent magnet material includes but is not limited to neodymium iron boron material.

As a further improvement of the invention, the permanent magnet is an axially magnetized ring-shaped permanent magnet. Along the axial direction, the upper and lower two parts of the rotor permanent magnet are of N level and S level, and the upper and lower two parts of the stator permanent magnet are of S level and N level. The two are mutually exclusive when placed.

As a further improvement of the invention, the biopsy working head is a biopsy needle or biopsy forceps, and a pressure sensor is arranged in the head part of the biopsy working head.

As a further improvement of the invention, a boss is arranged on the movable base, and the rear end of the biopsy working head is fixed on the boss.

As a further improvement of the invention, the protective shell is a cylindrical hollow structure with thin-wall characteristics, and the overall size of the capsule is reduced. The protective housing and the fixed base are in interference fit, the inner diameter of the protective housing is slightly smaller than the outer diameter of the fixed base, the left edge of the protective housing coincides with the left edge of the front fixed base, and the right end of the protective housing is in circular arc transition to limit the moving range of the rotor permanent magnet under the action of the repulsion force of the stator permanent magnet. The protective shell has the functions of protecting the sampling device from being interfered by the internal environment of a human body and maintaining the image acquisition function.

As a further improvement of the invention, the rear end of the protective shell is provided with a limit arc for limiting the backward movement range of the moving base.

As a further improvement of the invention, the edge of the fixed base coincides with the edge of the head of the capsule endoscope and is in interference fit with the shell, the inner diameter of the fixed base is slightly smaller than the diameter of the shell of the capsule endoscope, and the axis of the biopsy working head coincides with the central line of a reserved hole of the fixed base.

As a further improvement of the invention, the stator permanent magnet and the fixed base are in interference fit, and the position is kept unchanged in the biopsy sampling operation. The inner diameter of the stator permanent magnet is slightly smaller than the outer diameter of the fixed base.

As a further improvement of the invention, the connection mode of the tail end of the biopsy working head and the movable base is interference fit. The diameter of the upper hole of the lug boss of the movable base is slightly smaller than the diameter of the tail end of the biopsy working head.

As a further improvement of the invention, the connection mode of the movable base and the rotor permanent magnet is interference fit. The inner diameter of the annular rotor permanent magnet is slightly smaller than the outer diameter of the movable base, and the annular rotor permanent magnet is acted by a magnetic field force to drive the movable base to move axially together, so that the biopsy working head extends out.

As a further improvement of the invention, the applied driving gradient magnetic field can be an electromagnetic field excited by a combined electromagnetic coil or a permanent magnetic field excited by a permanent magnet. Under the drive of an external magnetic field, the direction of the magnetic field changes constantly and is inconsistent with the magnetization direction of the axially magnetized annular permanent magnet, the annular permanent magnet moves along the axial direction under the action of magnetic force, and the posture of the capsule is adjusted under the action of magnetic moment, so that the head of the capsule is perpendicular to the surface of the biopsy tissue, and the sampling success rate is improved.

As a further improvement of the invention, the fixed base, the biopsy working head, the movable base, the protective shell and other parts in the device are processed by nonmagnetic materials.

As a further improvement of the invention, the head material of the commercial magnetically-driven capsule endoscope is transparent, and the head is provided with a camera so as to facilitate the collection of images and the observation of the sampling process.

The invention has the beneficial effects that: the magnetic control biopsy mechanism provided by the invention is externally arranged on the surface of the magnetic drive capsule endoscope, has a simple structure, is easy to assemble and disassemble, does not need to change the existing structure, and increases the sampling function; the driving energy is remotely provided by an external magnetic field, a built-in battery is not needed, and the damage to a human body is reduced; the device can repeatedly perform sampling biopsy operation by applying an external magnetic field for multiple times, so that the sampling success rate is improved; the biopsy working head axially extends out, so that the sampling range is enlarged, a camera positioned at the head of the capsule is easy to be matched with an external magnetic field, and the sampling process is better observed; under the action of an external magnetic field, the rotor permanent magnet is attracted, and the stator permanent magnet is repelled, so that the pressure of the capsule on the inner wall of the gastrointestinal tract is reduced.

Drawings

FIG. 1 is a schematic view of a magnetically driven capsule endoscope incorporating a magnetically controlled sampling mechanism of the present invention.

FIG. 2 is an exploded view of a magnetic biopsy mechanism of a capsule endoscope according to the present invention.

FIG. 3 is a front cross-sectional view of a magnetically controlled biopsy mechanism of a capsule endoscope according to the present invention.

FIG. 4 is a front cross-sectional view of a capsule endoscope incorporating a magnetically controlled biopsy mechanism of the present invention.

Fig. 5 is a driving initial state diagram (without a protective case) of a capsule endoscope robot integrated with a magnetic control biopsy mechanism of the present invention.

FIG. 6 is a driving completion state diagram (without a protective case) of a capsule endoscope robot integrated with a magnetic control biopsy mechanism according to the present invention.

Fig. 7 is a schematic diagram (without a protective shell) of finding a target sampling point in the sampling process of a capsule endoscope robot integrated with a magnetic control biopsy mechanism.

FIG. 8 is a schematic diagram of the capsule endoscope robot integrated with the magnetic control biopsy mechanism to reach a target sampling point during sampling process (without a protective shell).

FIG. 9 is a schematic view of the capsule endoscopic robot with integrated magnetic controlled biopsy mechanism for sampling tissue samples (without a protective cover) according to the present invention.

FIG. 10 is a schematic diagram of the sampling process of a capsule endoscopic robot with an integrated magnetic controlled biopsy mechanism of the present invention (without a protective shell) leaving the target sampling point.

Detailed Description

The invention is further described with reference to the following description and embodiments in conjunction with the accompanying drawings.

Fig. 1 is a magnetic-driven capsule endoscope integrated with a magnetic control biopsy mechanism, which comprises a magnetic-driven capsule 1 and a magnetic control biopsy mechanism 2.

As shown in fig. 2 to 10, a magnetic control biopsy mechanism of a capsule endoscope is composed of a fixed base 201, a stator permanent magnet 202, a biopsy working head 203, a mover permanent magnet 204, a movable base 205 and a protective shell 206.

The fixed base 201 is fixed on the surface of the shell through interference fit with the capsule shell of the magnetic drive capsule 1, and is used as a guide device of the biopsy working head 203 to limit the moving direction and range of the biopsy working head 203. The stator permanent magnet 202 is in interference fit with the fixed base 201 and is fixed at the fixed base 201. The biopsy working head 203 and the motion base 205 are interference fit. The rotor permanent magnet 204 and the movable base 205 are in interference fit and move synchronously. The stator permanent magnet 202 and the mover permanent magnet 204 repel each other in an initial state, and the protective case 206 limits an initial position of the mover permanent magnet 204. After an external magnetic field is applied, the rotor permanent magnet 204 and the movable base 205 move along the axial direction, so that the biopsy working head 203 fixedly connected to the movable base 205 extends out of a reserved hole of the fixed base 201 at the front end to perform sampling biopsy operation. After the external magnetic field is removed, the stator permanent magnet 202 repels the rotor permanent magnet 204, so that the biopsy working head 203 is recovered to the inside of the protective shell 206, thereby completing one sampling movement. The protective shell 206 isolates other elements of the device from the internal environment of the human body, while limiting the initial and return positions of the mover permanent magnets 204.

The applied external magnetic field may be a driving gradient magnetic field.

The additional driving gradient magnetic field can be an electromagnetic field excited by a combined electromagnetic coil or a permanent magnetic field excited by a permanent magnet. Under the drive of an external magnetic field, the direction of the magnetic field changes constantly and is inconsistent with the magnetization direction of the axially magnetized annular permanent magnet, the annular permanent magnet moves along the axial direction under the action of magnetic force, and the posture of the capsule is adjusted under the action of magnetic moment, so that the head of the capsule is perpendicular to the surface of the biopsy tissue, and the sampling success rate is improved.

The biopsy working head 203 is preferably a biopsy needle.

Sampling modalities include, but are not limited to, needle biopsy. The invention adopts needle-punching biopsy and organ puncture examination in clinic, and is a method for obtaining a sample by utilizing a thin needle to prick into a tissue. The clamp type biopsy can also be adopted, namely the biopsy working head is replaced by a biopsy clamp and the like.

The number of biopsy heads 203 can be adjusted according to actual conditions. The invention adopts 4 biopsy working heads 203 distributed at intervals of 90 degrees, and can properly increase the biopsy working heads if sampling in a larger range and sampling results are more accurate, and can properly reduce the biopsy working heads if the quality of the biopsy device is required to be reduced.

The head of the biopsy working head 203 is internally provided with a pressure sensor. So as to determine whether the sampling operation can be performed and prevent the human body from being hurt.

It can be seen from fig. 3 that the rotor permanent magnet 204 is annular and is in interference fit with the movable base 205, that is, when an external magnetic field exists, the rotor permanent magnet 204 is attracted to drive the movable base 205 to move, and a cylindrical boss exists on the movable base 205 and is in interference fit with the biopsy needle to drive the biopsy needle to move synchronously. The biopsy needle axially protrudes from a prepared hole of the fixed base 201; when the external magnetic field is removed, the rotor permanent magnet 204 and the movable base 205 move towards the tail end of the capsule due to the interaction force of the magnetic field, and the biopsy needle returns to the range of the protective shell 206, so that the sampling process is completed. The external magnetic field is repeatedly applied or removed, and multiple sampling operations can be completed.

FIG. 4 is a front cross-sectional view of a capsule endoscope incorporating a magnetically controlled biopsy mechanism of the present invention. It can be seen from fig. 4 that the sampling device is small in overall size relative to the capsule endoscope and is easy to swallow. The fixed base 201 is in interference fit with the capsule shell, the position of the fixed base 201 is always kept unchanged, and a hole suitable for the biopsy working head 202 to pass through is reserved on the fixed base 201, so that the fixed base has a guiding function. The outermost protective shell 206 is in interference fit with the fixed base 201, namely fixed on the surface of the capsule shell, and separates other parts which are not easy to directly contact with the human environment. Compared with the original state, the capsule endoscope integrated with the biopsy device has the advantages that the internal structure is unchanged, the thickness is slightly increased, the transition positions of the head and the tail of the capsule endoscope robot at the front end of the device are parallel and level, the rear end of the capsule endoscope robot is in arc transition, the whole capsule endoscope is still in a capsule shape and is easy to swallow.

FIG. 5 is a diagram of the initial driving state of a capsule endoscope integrated with a magnetic controlled biopsy mechanism (without the protective cover 206). FIG. 6 is a driving completion state diagram of a capsule endoscope integrated with a magnetic control biopsy mechanism (without a protective cover 206).

As can be seen from FIG. 5, when no magnetic field force is applied, unlike magnetic poles of the stator permanent magnet 202 and the rotor permanent magnet 204 repel each other, and the biopsy working head 203 is located within the protective shell 206, so as to prevent the tip of the biopsy working head 203 from damaging the human body. As can be seen from FIG. 6, when an external magnetic field is applied, the magnetic field force between the two magnets is overcome, and the rotor permanent magnet 204 drives the biopsy working head 203 to extend out for sampling operation. At this time, the extension range of the biopsy working head 203 reaches the maximum value, and a gap is left between the rotor permanent magnet and the stator permanent magnet because the repulsive force between the magnets cannot be completely overlapped.

Fig. 7 to 9 are schematic diagrams of the sampling process of a capsule endoscope integrated with a magnetic control biopsy mechanism (without a protective shell 206). The magnetic control biopsy mechanism of the capsule endoscope is described in the practical scene as follows:

the magnetic control capsule endoscope system consists of a capsule endoscope, a capsule endoscope navigation system, a real-time monitoring system and a data recorder. The sampling device of the capsule endoscope comprises a permanent magnet, therefore, in the gastroscopy process, a human body swallows a capsule robot containing magnetic materials, an external magnetic field generated by a capsule endoscope navigation system generates enough force and moment to control the movement of the capsule, so that the capsule can be inclined, translated and rotated in the stomach, the body position of an examinee is changed for examination, the digital signal is transmitted to a data recorder carried outside the body in a wireless and real-time manner, and a doctor can make analysis and diagnosis on the state of an illness through image data received by a real-time monitoring system observation recorder.

As shown by the finding of the target sampling points in fig. 7, the examination is started to find suspicious lesions.

As shown in fig. 8, when the target sampling point is reached, the size and the direction of an external magnetic field are changed by the navigation system of the capsule endoscope, the posture of the capsule is adjusted, the head of the capsule is kept vertical to the plane of the sampled tissue, and the magnetic force exerted on the biopsy device is insufficient to extend the biopsy needle. If the pathological sampling position is special, the size and the direction of the external magnetic field are changed, so that the biopsy process is completed after the capsule rotates for a certain angle.

As shown in fig. 9 for collecting a sample tissue, a large magnetic field force enough to overcome the magnetic field force between the stator permanent magnet 202 and the rotor permanent magnet 204 of the sampling device is applied by the external magnetic field, so that the rotor permanent magnet 204 of the sampling device moves along the axial direction, and the biopsy working head 203 slowly extends out. When the biopsy working head 203 contacts with the biopsy tissue, the pressure sensor at the front end is in a normal range and within a threshold value, the external magnetic field is continuously increased, and the rotor permanent magnet 204 drives the biopsy working head 203 to insert into the target tissue. While repelling the stator permanent magnets 202, the capsule is less stressed against the inner wall of the gastrointestinal tract. If the pressure exceeds the normal range, the values of the magnetic field and the pressure sensor are changed by adjusting the position of the probe in the capsule endoscope navigation system so as to avoid the damage to the human body caused by overlarge magnetic field, and the process can be automatically adjusted by the capsule endoscope navigation system.

As shown in fig. 10, when the sampling is finished by the biopsy working head 203, the magnetic field is removed by the capsule endoscope navigation system, the stator permanent magnet 202 returns the stator permanent magnet 204 to the original position, and the biopsy working head 203 is recovered, so that the sampling is finished. The remaining inspection process is then completed by applying the external magnetic field again.

After the examination is finished, the biopsy working head 203 extends out of the protective shell 206 by utilizing an external magnetic field generated by a permanent magnet or an electromagnetic field, and a sampled tissue is extracted for lesion analysis.

The magnetic control biopsy mechanism applied to the magnetic drive capsule endoscope provided by the invention has the following advantages:

1. on the basis of the existing commercial capsule endoscope, the existing internal structure does not need to be changed, the external integrated sampling device reduces the use of the internal space of the capsule, and the device has simple structure and high efficiency.

2. The driving force of the device comes from an external magnetic field, the energy of the capsule endoscope robot is not consumed, and the damage to a human body is reduced.

3. The device can repeatedly perform sampling biopsy operation by applying an external magnetic field for multiple times, so that the sampling success rate is improved;

4. the biopsy working head axially extends out, the sampling range is enlarged, a camera positioned at the head of the capsule is easy to be matched with an external magnetic field, and the whole sampling process is monitored in real time.

5. Under the action of an external magnetic field, the rotor permanent magnet is attracted, and the stator permanent magnet is repelled, so that the pressure of the capsule on the inner wall of the gastrointestinal tract is reduced.

The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.

Claims

1. The utility model provides a capsule endoscope's magnetic control biopsy mechanism which characterized in that: the capsule endoscope comprises a fixed base, a stator permanent magnet, a biopsy working head, a rotor permanent magnet, a movable base and a protective shell, wherein the fixed base, the stator permanent magnet, the biopsy working head, the rotor permanent magnet and the movable base are all positioned in the protective shell, the fixed base is fixed outside the capsule endoscope, the stator permanent magnet is fixed on the fixed base, the rotor permanent magnet is fixed on the movable base, the rear end of the biopsy working head is fixed on the movable base, the front end of the biopsy working head is in guide fit with the fixed base, after an external magnetic field is applied, the rotor permanent magnet and the movable base synchronously move along the axial direction, so that the biopsy working head fixedly connected on the movable base extends out of the fixed base at the front end to carry out sampling biopsy operation, and after the external magnetic field is removed, the stator permanent magnet repels the rotor permanent magnet, thereby the biopsy working head is recovered and reset, the fixed base is in a circular ring shape, the shell of the capsule endoscope is in a cylindrical shape, the fixed base and the shell of the capsule endoscope are in interference fit, the fixed base is fixed on the outer surface of the shell of the capsule endoscope, the movable base is in a circular ring shape, the movable base and the outer surface of the shell of the capsule endoscope are in sliding fit, the fixed base, the stator permanent magnet, the rotor permanent magnet, the movable base, the protective shell and the shell of the capsule endoscope are coaxially arranged, the fixed base, the biopsy working head, the movable base, the protective shell and the shell of the capsule endoscope are made of non-magnetic materials, the fixed base is provided with a guide through hole which is axially arranged, the front end of the biopsy working head is arranged on the guide through hole in a penetrating manner, and the stator permanent magnet and the rotor permanent magnet are both axially magnetized circular ring type permanent magnets, the stator permanent magnet and the mover permanent magnet repel each other in an initial state.

2. The magnetically controlled biopsy mechanism of a capsule endoscope of claim 1, wherein: the biopsy working head is a biopsy needle or biopsy forceps, and a pressure sensor is arranged in the head of the biopsy working head.

3. The magnetically controlled biopsy mechanism of a capsule endoscope of claim 1, wherein: the movable base is provided with a boss, and the rear end of the biopsy working head is fixed on the boss.

4. The magnetically controlled biopsy mechanism of a capsule endoscope of claim 1, wherein: the protective housing is cylindrical hollow structure, has the thin wall characteristic, the protective housing with fixed baseplate is interference fit.

5. The magnetically controlled biopsy mechanism of a capsule endoscope of claim 4, wherein: the rear end of the protective shell is provided with a limiting arc for limiting the backward moving range of the moving base.