CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation application of U.S. application Ser. No. 10/395,745 filed on Mar. 24, 2003 which claims benefit of Japanese Application No. 2002-84387 filed on Mar. 25, 2002, the contents of each of which are incorporated by reference.
BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a capsule-type medical device which is passed through the body cavity and is capable of examination, therapy, and/or treatment.
2. Description of the Related Art
Capsule-type medical devices are known as medical devices which are swallowed by patients to pass through the body cavity tract, which can perform examination, therapy, and/or treatment.
Such capsule-type medical devices comprise treatment tools for performing such medical treatment, such as a medication-depositing unit for depositing medicine, treatment devices such as forceps or the like, treatment devices for performing incision or coagulation by ultrasonic or high-frequency means, and so forth, and are arranged to perform such medical treatment at an object portion in the body cavity tract. However, there are shortcomings within the capsule-type medical devices, such as requiring a long time to reach the object portion unless guided through the body cavity tract.
To deal with this problem, Japanese Patent Publication No. 3017770 discloses a capsule-type medical device comprising a magnet which is magnetically manipulated by a magnet outside of the body of the subject. With the medical device described in Japanese Patent Publication No. 3017770 (hereafter referred to simply as “No. 3017770”), an external uniform magnetic field uniaxially acts upon magnets provided on the outer perimeter of a capsule main body in the vertical direction, so that the capsule is guided through the body cavity tract without rotating, primarily. Also, an arrangement is also disclosed wherein an alternating magnetic field is applied externally, so as to rotate the main body. However, efficiently propelling rotational motion of the main unit is not easy.
Note that this No. 3017770 is equivalent to the Japanese Patent Application with Application No. H2-109696 (filed on Apr. 25, 1990) which is cited as proof of prior application in the later-described U.S. Pat. No. 5,681,260.
On the other hand, with the capsule-type medical device described in Japanese Unexamined Patent Application Publication No. 2001-179700 (hereafter referred to simply as “No. 2001-179700”), an external rotating magnetic field acts triaxially on a magnet provided within the capsule main unit in the vertical direction and horizontal direction, so as to gain propulsion by rotationally turning.
With the capsule-type medical device described in No. 2001-179700, a thrust generating unit which obtains propulsion by rotating is provided in the capsule main unit. However, with the capsule-type medical device described in No. 2001-179700, no consideration has been given to the internal structure of the capsule main unit with regard to rotations of the capsule main unit.
Accordingly, the capsule-type medical device described in No. 2001-179700 may make useless motions such as rotating eccentrically (zigzagging), and accordingly take time to reach the object position in the body cavity tract, rather than reaching the location smoothly.
Also, U.S. Pat. No. 5,353,807 discloses a configuration comprising a slender and flexible recovery member, a main unit disposed on the tip thereof for performing medical treatment, a coil provided on the circumference to the main unit for guiding with an eternal magnetic flux, and multiple propulsion plates provided on the recovering member, thereby enabling the direction of the main unit to be controlled by the magnetic polarity generated by the coil and the external magnetic flux, and further guiding the main unit through the body cavity by a propulsion plate provided on the recovering member.
This patent also discloses an arrangement of a main unit comprising an internal magnet and battery, with the capsule not being provided with the recovering member but rather guided by the external magnetic field.
However, with the arrangement described in this U.S. Patent, the direction of the magnetic polarity generated by the coil or the magnet is in the longitudinal direction of the main unit, so smooth propulsion by an external magnetic field is not easy.
Also, U.S. Pat. No. 5,681,260 also discloses a device wherein an endoscope insertion portion or the like is magnetically guided through the body cavity, besides the embodiment relating toFIGS. 50 through 76B corresponding to No. 3017770.
The arrangement described in this U.S. patent has a similar configuration as that in No. 3017770, and smooth propulsion of the endoscope insertion portion or the like is not easy.
Further, the above-described preceding examples do not disclose contents corresponding to the Claims of the Present Invention.
SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a capsule-type medical device with little useless motions such as eccentric rotations, and which can be smoothly and readily propelled through body cavities.
It is another object of the present invention to provide a capsule-type medical device which can be readily propelled through bending body cavities.
To achieve these objects, the capsule-type medical device according to the present embodiment comprises: a capsule main unit provided with functions for performing medical acts such as examination, therapy, and/or treatment; a magnet provided to the capsule main unit, for magnetically acting upon an external magnet outside of the subject; and a propulsion generating unit for converting rotational motion due to the magnet into propelling force; wherein the center of gravity of the capsule main unit generally matches the center axis of the capsule main unit in the longitudinal direction, thereby suppressing useless motions such as eccentric rotations, and enabling the capsule-type medical device to be smoothly propelled through the body cavity to the target position.
BRIEF DESCRIPTION OF THE DRAWINGSFIGS. 1 through 14B relate to a first embodiment of a present embodiment, whereinFIG. 1 is an overall configuration diagram illustrating a medical system with the first embodiment of the present invention;
FIG. 2 is a block diagram illustrating the configuration of the electrical system according of the capsule-type medical device according to the first embodiment;
FIG. 3A is a cross-sectional diagram illustrating the configuration of the capsule-type medical device;
FIG. 3B is a frontal view illustrating the tip side of the arrangement shown inFIG. 3A;
FIG. 3C is a rear side view illustrating the rear end view of the arrangement shown inFIG. 3A;
FIG. 3D is a cross-sectional view illustrating the configuration of the capsule-type medical device with the placement position of the magnet changed;
FIG. 4A is an external explanatory diagram of a capsule-type medical device for spreading a medicine;
FIG. 4B is an external view of the tip side of the capsule-type medical device shown inFIG. 4A;
FIG. 5A is an explanatory diagram illustrating a capsule-type medical device comprising a treatment tool storage unit and ultrasonic unit, wherein an elastic rubber cover having a spiral groove formed thereupon is detachably mounted to the capsule main unit;
FIG. 5B is a perspective view illustrating a part of the elastic rubber cover shown inFIG. 5A;
FIG. 6A is a cross-sectional diagram illustrating a capsule-type medical device wherein a spiral portion provided to the rear side with regard to the direction of progression is detachably provided, and an observation devices is provided on the rear side with regard to the direction of progression;
FIG. 6B is a transverse cross-sectional diagram of the arrangement shown inFIG. 6A;
FIG. 7A is a cross-sectional view illustrating a capsule-type medical device wherein multiple magnets are symmetrically disposed on the center axis of the capsule main unit in the longitudinal direction;
FIG. 7B is a transverse cross-sectional diagram of the arrangement shown inFIG. 7A;
FIG. 8A is a cross-sectional view illustrating a capsule-type medical device wherein a spiral portion is detachably provided to the side at the direction of progression, while an observation device is provided on the rear side with regard to the direction of progression;
FIG. 8B is a cross-sectional diagram viewing the arrangement shown inFIG. 8A from the lower side of the drawing;
FIG. 9A is an explanatory diagram illustrating a capsule-type medical device which is recovered by a recovery tool inserted through a treatment device insertion channel of an endoscope;
FIG. 9B is a transverse cross-sectional view at the tip side of the arrangement shown inFIG. 9A;
FIGS. 10A through 10C show a configuration wherein the capsule main unit can be divided into the two parts of a portion where an observation device is disposed, and a portion where a magnet and spiral portion are disposed, whereinFIG. 10A is an explanatory diagram illustrating a capsule-type medical device wherein the observation field of view of the observation device is directed backwards;
FIG. 10B is an explanatory diagram illustrating a capsule-type medical device wherein the observation field of view of the observation device is directed diagonally backwards;
FIG. 10C is an explanatory diagram illustrating a capsule-type medical device wherein the observation field of view of the observation device is directed toward the side;
FIG. 11A is an explanatory diagram illustrating a capsule-type medical device wherein a portion to which a spiral portion is provided is formed at a flexible insertion portion;
FIG. 11B is a transverse cross-sectional diagram of the arrangement shown inFIG. 11A;
FIG. 12A is an explanatory diagram illustrating a capsule-type medical device provided with a ring-shaped magnet;
FIG. 12B is a transverse cross-sectional diagram of the arrangement shown inFIG. 12A;
FIGS. 13A through 13C illustrate a capsule-type medical device wherein a spiral portion is provided on the opposite side as to a flexible insertion portion on one end of the capsule main unit which is the progression direction thereof in the longitudinal direction, whereinFIG. 13A is an explanatory diagram illustrating a capsule-type medical device wherein the spiral portion is provided over almost the entire circumference of the rear side of the capsule main unit;
FIG. 13B is an explanatory diagram illustrating a capsule-type medical device wherein the spiral portion is provided diagonally over half of the rear side of the capsule main unit so as to enable diagonally viewing in the backward direction;
FIG. 13C is an explanatory diagram illustrating a capsule-type medical device wherein the spiral portion is provided over half of the rear side of the capsule main unit so as to enable viewing sideways;
FIG. 14A is an explanatory diagram illustrating a capsule-type medical device wherein the flexible insertion portion is detachably mounted to the capsule main unit;
FIG. 14B is an explanatory diagram illustrating that the flexible insertion portion is bendable in the direction generally orthogonal to the longitudinal direction;
FIGS. 15 through 21 relate to a second embodiment of the present invention, whereinFIG. 15 is an explanatory diagram illustrating a capsule-type medical device according to the second embodiment of the present invention;
FIG. 16 is an explanatory diagram illustrating the operations of the capsule-type medical device shown inFIG. 15 within the body cavity;
FIG. 17 is an explanatory diagram illustrating the relation between the length of the rigid portion of the capsule main unit and the length of the soft portion of the flexible insertion portion, with regard to the maximum diameter of the tubular body cavity organ;
FIG. 18 is an explanatory diagram of the operations of the capsule-type medical device shown inFIG. 15 in bent or narrow portions or the like in tubular body cavity organs;
FIG. 19 is an external diagram illustrating a capsule-type medical device wherein the spiral portion is formed by adhesion and fixing of a wire-like material to the outer perimeter of the flexible insertion portion;
FIG. 20 is an explanatory diagram illustrating a capsule-type medical device wherein the flexible insertion portion is configured with multiple ball-shaped protrusions formed with ball-shaped magnets built therein, formed thereupon;
FIG. 21 is an explanatory diagram illustrating the operations of the capsule-type medical device shown inFIG. 20 inside the body cavity;
FIGS. 22 and 23 relate to a third embodiment of the present invention, whereinFIG. 22 is an explanatory diagram illustrating a capsule-type medical device according to the third embodiment of the present invention; and
FIG. 23 is an explanatory diagram illustrating a modification example of the capsule-type medical device shown inFIG. 22.
DESCRIPTION OF THE PREFERRED EMBODIMENTS The following is a description of embodiments of the present invention, with reference to the drawings.
First Embodiment A first embodiment of the present invention will be described with reference toFIGS. 1 through 14B. The primary object of the present embodiment is to provide a device and method wherein a capsule-type medical device which performs medical actions can be rotated by external magnetism and thus be smoothly guided to a target portion or beside a target portion; more specifically, to provide a device and method wherein eccentric motion in rotation is suppressed so as to enable effective or smooth propulsion to beside the target portion.
As shown inFIG. 1, a capsule-typemedical device1 exchanges radio waves with a capsule control device (hereafter referred to simply as “control device”)3 while passing through the body cavity tract of apatient2, thus configuring a medical system4 enabling examination, therapy, and/or treatment, under control of thiscontrol device3.
The medical system4 is for performing screening of the esophagus, duodenum, small intestine, large intestine, etc., by swallowing the capsule-typemedical device1 with water or the like in the same way that one would swallow medicine, following precleaning of the large intestine (lavage of the intestinal tract). In the event that the capsule-typemedical device1 passes through an area of interest rapidly, as with the duodenum for example, the medical system4 takes images at a rate of 10 frames per second, and on the other hand, takes images at 2 frames per second for areas passed through slowly, such as the small intestine, for example. The images that are taken are subjected to necessary signal processing and digital compression processing and then transmitted to thecontrol device3, and only information necessary is recorded as moving images so as to be used for diagnosis.
Also, the medical system4 is configured comprising amagnetic guiding device5 which magnetically guides the capsule-typemedical device1. Note thatFIG. 1 only shows themagnetic guiding device5 schematically. Themagnetic guiding device5 is configured so as to form a rotating magnetic field which magnetically acts upon a later-described magnet provided in a capsulemain unit1A of the capsule-typemedical device1. Also, themagnetic guiding device5 is connected to thecontrol device3, such that thecontrol device3 can control the direction of the generated rotating magnetic field.
Thecontrol device3 comprises a personal computermain unit11 having functions for controlling the capsule-typemedical device1 and themagnetic guiding device5, akeyboard12 which is connected to the personal computermain unit11 for inputting commands, data, etc., amonitor13 which is connected to the personal computermain unit11 for displaying images and the like, and anexternal antenna14 which is connected to the personal computermain unit11 for transmitting control signals for controlling the capsule-typemedical device1 and receiving signals from the capsule-typemedical device1.
Thecontrol device3 is arranged such that the control signals for controlling the capsule-typemedical device1 and themagnetic guiding device5 are generated based on key input from thekeyboard12 or by a control program stored in a hard disk or the like within the personal computermain unit11.
The control signals for controlling themagnetic guiding device5 are transmitted from the external computermain unit11 to themagnetic guiding device5 by a connecting cable not shown in the drawings.
Themagnetic guiding device5 generates the rotating magnetic field wherein the direction of the rotating magnetic field is controlled, based on the transmitted control signals. The capsule-typemedical device1 is configured such that the rotating magnetic field generated by themagnetic guiding device5 magnetically acting upon the later-described magnet rotates the capsulemain unit1A such that the direction of progression of the capsulemain unit1A within the body cavity is set by a later-described propulsion generating unit, and also such that motive energy for propulsion of the capsulemain unit1A is generated.
On the other hand, the control signals for controlling the capsule-typemedical device1 are modulated by carrier waves of a predetermined frequency at an oscillating circuit within the personal computermain unit11, and transmitted as radio waves from theexternal antenna14.
The capsule-typemedical device1 receives the radio waves with a later-describedwireless antenna21, the control signals are demodulated, and the demodulated control signals are output to the component circuits and the like.
Also, thecontrol device3 receives signals including image information of video signals and the like transmitted from thewireless antenna21 of the capsule-typemedical device1 with theexternal antenna14, and displays images and the like on themonitor13.
Next, a detailed configuration of the capsule-type medical device according to the present embodiment will be described with reference toFIGS. 2 through 3C. Note that the present embodiment is a capsule-type medical device capable only of examination (observation).
The capsule-typemedical device1 is primarily configured of awireless antenna21 which exchanges radio waves with thecontrol device3, a wireless transmission/reception circuit22 which subjects the radio waves exchanged with thewireless antenna21 to signal processing, anillumination device23 of LEDs (Light-Emitting Diodes) or the like which emits illumination light for illuminating the body cavity, an observation device (imaging device)24 for acquiring optical images of the body cavity illuminated with the illumination light from theillumination device23 so as to take images, a digitalsignal processing circuit25 for performing digital signal processing or the like with regard to the imaging signals obtained from theimaging device24, abattery unit26 where abattery26aof some sort is stored, and aswitch27 which turns electrical power supplied from thebattery unit26 off and on.
The wireless transmission/reception circuit22 selectively extracts carrier waves of the radio waves received from thecontrol device3 using thewireless antenna21, and performs detection, demodulation of control signals, and output thereof to the component circuits, as well as modulating information signals such as video signals or the like from the component circuits with carrier waves of a predetermined frequency, and transmitting these from thewireless antenna21 as radio waves.
Theobservation device24 is configured of an objectoptical system31 for acquiring optical images, animaging sensor32 such as a CMOS (Complementary Metal-Oxide Semiconductor) or the like for imaging the optical images acquired by the objectoptical system31, and animaging driving circuit33 for driving theimaging sensor32.
The digitalsignal processing circuit25 is configured of a digital video signal processing circuit (hereafter referred to as “video signal processing circuit”)34 which subjects the imaging signals taken by theimaging sensor32 to signal processing and converts these into digital video signals, and a digital compression processing circuit (hereafter referred to as “compression processing circuit”)35 which subjects the converted digital video signals to compression processing.
Thebattery unit26 supplies electric power from the storedbattery26ato theillumination device23, the digitalsignal processing circuit25, and the wireless transmission/reception circuit22 through theswitch27. Note that theobservation device24 is supplied electric power from thebattery26avia the digitalsignal processing circuit25.
Also, the capsule-typemedical device1 has built in a permanent magnet (hereafter referred to simply as “magnet”)36 upon which the rotating magnetic field, generated by themagnetic guiding device5 as described above, acts. The magnet used there is a permanent magnet such as a neodymium magnet, samarium-cobalt magnet, ferrite magnet, iron-chromium-cobalt magnet, platinum magnet, Alnico (AlNiCo) magnet, and so forth.
Rare-earth magnets such as neodymium magnets and samarium-cobalt magnets have strong magnetism and are advantageous in reducing the size of the magnet built into the capsulemain unit1A. On the other hand, ferrite magnet are advantageous in that the cost is low. Further, platinum magnets have excellent corrosion resistance, and are suitable for medical purposes.
Also, themagnet36 built into the capsulemain unit1A needs not be a permanent magnet, and rather may be formed of a coil instead. In this case, the capsulemain unit1A may generate magnetism at the coil by current from an electric power source such as a built-in battery or the like, or the coil may be magnetized by electric power temporarily stored in an built-in capacitor or the like.
Further, instead of a built-in power source, the capsulemain unit1A may have a coil built in which is used to generate electricity, which is stored in a capacitor and used to magnetize a separate coil. In this case, the limit on capacity of a built-in battery is done away with for the capsulemain unit1A, thereby enabling operations over long periods of time. Also, the same coil may be used for the coil for generating electricity and the magnetizing coil.
As shown inFIGS. 3A through 3C, the capsule-typemedical device1 has a cylindrical capsulemain unit1A covered with a transparent mainunit exterior member41 in an airtight manner, with components built in such as the above-describedillumination device23 andobservation device24 being positioned within the cylindrical capsulemain unit1A. More specifically, the objectoptical system31 making up theobservation device24 is positioned at the center portion of the tip side of the cylindrical capsulemain unit1A of the capsule-typemedical device1, and theimaging sensor32 is positioned at the image focus location of the objectoptical system31.
Theimaging driving circuit33 is formed so as to surround theimaging sensor32. The digitalsignal processing circuit25 is positioned at the base side of theimaging driving circuit33 and theimaging sensor32, with the wireless transmission/reception circuit22 disposed at the base side of the digitalsignal processing circuit25.
Also, theillumination device23 is formed so as to surround the objectoptical system31, thereby illuminating in front of the capsulemain unit1A with illumination light through the transparent mainunit exterior member41. As shown inFIG. 3B, theillumination device23 is configured of an array of four white LEDs, for example.
Thebattery unit26 is provided on the rear side of the wireless transmission/reception circuit22, with threebatteries36asuch as button batteries stored in thebattery unit26. Upon thebattery unit26 being turned on by theswitch27 being operated externally, an operation which is not indicated in the drawings, electric power is supplied to theillumination device23 and the like through theswitch27. Themagnet36 is positioned behind thebattery unit26, with thewireless antenna21 positioned further behind.
The capsule-typemedical device1 has the above-described built-in components reinforced and held by a cylindrical member such as a metal ring reinforcing member not shown in the drawings, and placed in the mainunit exterior member41. The capsule-typemedical device1 is formed to a size wherein thepatient2 can swallow the capsulemain unit1A without much trouble.
Also, the capsule-typemedical device1 has themagnet36 disposed therein such that the poles N and S are perpendicular to thecenter axis38 in the longitudinal direction of the cylindrical shape of the capsulemain unit1A, as shown inFIG. 3A (i.e., inFIG. 3A, thecenter axis38 is horizontal, and the direction of magnetic polarity is vertical, which is perpendicular thereto).
Thus, with the capsule-typemedical device1, upon the rotating magnetic field generated by themagnetic guiding device5 acting upon themagnet36, the capsulemain unit1A rotates on thelongitudinal center axis38 due to themagnet36 being acted upon.
Also, the capsule-typemedical device1 is provided with a propulsion generating unit on the outer perimeter of the capsulemain unit1A, which is aspiral portion37 made up ofspiral grooves37athrough which fluids such as gas and liquids in the body cavity can flow through in either direction, andspiral ridges37bwhere portions next to thespiral grooves37aprotrude in a spiraling manner. Note that thespiral ridges37bare formed with curved faces so as to smoothly come into contact with the inner walls of the body cavity.
Providing such aspiral portion37 allows the capsule-typemedical device1 to move forward or backwards according to rotations of the capsulemain unit1A, since rotations are converted into propulsion force as the fluids such as gas and liquids in the body cavity pass through thespiral grooves37amaking up thespiral portion37.
Also, the capsulemain unit1A can be propelled following the spirals upon rotation, by using the friction between the protrusions of thespiral ridges37bmaking up thespiral portion37 and the mucous membranes.
That is to say, in the event that the protrusions of thespiral ridges37bcome into contact with the inner walls, and the capsulemain unit1A is rotated in that state, the capsulemain unit1A rotates in a state wherein spinning free is restricted by the friction at the point of contact, so the rotations propel the capsulemain unit1A in spiral fashion as to the inner walls. Reversing the direction of rotation allows the direction or progression of the capsulemain unit1A to be reversed.
Let us say that the spiral protrusions formed for thespiral ridges37bare cyclically formed with a pitch of p, for example. In a normal state of use wherein thespiral ridges37bare in contact with the tubular inner walls, one rotation of the capsulemain unit1A propels the capsulemain unit1A by the pitch p.
Note that the capsule-typemedical device1 is capable of changing the direction in which it is traveling according to the direction of rotation in which the capsulemain unit1A rotates so as to match the rotating plane of themagnet36 and the rotating plane of the rotating magnetic field according to the rotation of the rotating magnetic field.
Generally, with such a capsule-typemedical device1, the capsulemain unit1A may make useless motions such as eccentric motion (zigzagging) unless the center of gravity is not generally upon thelongitudinal center axis38 of the capsulemain unit1A.
With the present embodiment, the capsule-typemedical device1 is configured such that the batteries27asuch as button batteries or the like, which are the heaviest built-in components, are positioned on thecenter axis38 close to the center in the longitudinal direction, and thecenter36aof the direction of magnetism of themagnet36 is positioned on thecenter axis38 of the capsulemain unit1A, so that the center of gravity G of the capsulemain unit1A is generally on thecenter axis38 of the capsulemain unit1A, as shown inFIG. 3A.
Also, the built-in components may be arranged so as to match the center of gravity G of the capsulemain unit1A by changing the position of themagnet36 shown inFIG. 3A such that thecenter36aof the direction of magnetism of themagnet36 is positioned on thecenter axis38 of the capsulemain unit1A, as with the capsule-typemedical device1 shown inFIG. 3D.
Configuring the capsule-typemedical device1 thus enables smooth guiding to the target position through the tubular body cavity or lumen without useless motions such as eccentric movement (zigzagging) of the capsulemain unit1A.
Next, the operations of the capsule-typemedical device1 according to the present invention will be described.
As shown inFIG. 1, in the event that there is the need to observe a body cavity tract such as thestomach51 for example, of thepatient2, for long periods of time, the operator has the patient swallow the capsule-typemedical device1, and causes the device to pass through the stomach. Immediately prior to having thepatient2 swallow the capsule-typemedical device1, the operator turns theswitch27 thereof on, so that electric power from thebatteries26ain thebattery unit26 is supplied to theillumination device23, theobservation device24, the digitalsignal processing circuit25, and the wireless transmission/reception circuit22.
At the same time, the operator activates (turns on) themagnetic guiding device5, and magnetically controls the capsule-typemedical device1 with the rotating magnetic field generated by themagnetic guiding device5 so that the capsule-typemedical device1 reaches the target portion.
As described above, with the capsule-typemedical device1, upon the rotating magnetic field generated by themagnetic guiding device5 acting upon themagnet36, the capsulemain unit1A is rotated by the force which themagnet36 receives.
Then, the rotational force of the capsulemain unit1A is converted into propulsion and the capsule-typemedical device1 proceeds forwards or retreats backwards, due to at least one of: fluids such as gas and liquids in the body cavity passing through thespiral grooves37a;and thespiral ridges37bsmoothly coming into contact with the inner walls of the body cavity. Further, in the event that the capsulemain unit1A comes into contact with the inner walls of the body cavity, the capsulemain unit1A is held by friction between the mucous membranes on the inner walls of the body cavity and thespiral ridges37b,so rotations in this state are converted into greater propulsion force for proceeding forwards or retreating backwards. The capsule-typemedical device1 is capable of changing the direction in which it is traveling by the capsulemain unit1A rotating with the rotating plane of themagnet36 matching the rotating plane of the rotating magnetic field, according to the rotation of the rotating magnetic field.
Moreover, the capsule-typemedical device1 is capable of smoothly moving through the lumen to the target position without the capsulemain unit1A making useless motions such as eccentric movement.
The capsule-typemedical device1 passes through theoral cavity52 and theesophagus53, and reaches thestomach51. Now, the major axial diameter of theesophagus53 is16 mm and the minor axial diameter thereof is 14 mm, for example, so the capsule-typemedical device1 can easily pass through if formed with a generallycircular cross-section 14 mm or less in outer diameter.
In the event that there is the need to observe the inside of thestomach51, the operator performs input corresponding to a command for staring observation, from akeyboard12 for example of thecontrol device3. Control signals from this key input are emitted as radio waves from theexternal antenna14 of thecontrol device3, and transmitted to the capsule-typemedical device1.
The capsule-typemedical device1 detects operation-start signals from the signals received with thewireless antenna21, and drives the wireless transmission/reception circuit22,illumination device23,observation device24, and digitalsignal processing circuit25.
Theillumination device23 emits illumination light in the direction of the field of view of theobservation device24, the optical image of the range of the field of view illuminated is imaged on theimaging sensor32 of theobservation device24, subjected to photo-electric conversion, and an imaging signal is output. This imaging signal is converted into digital video signals at the videosignal processing circuit34 of the digitalsignal processing circuit25, subjected to compression processing at the digitalcompression processing circuit35 and modulated at the wireless transmission/reception circuit22, and emitted from thewireless antenna21 as radio waves.
The radio waves are received with theexternal antenna14 of thecontrol device3, demodulated with the reception circuit within the personal computermain unit11, converted into digital signals with an A/D converter within the personal computermain unit11, and stored in memory, while also read out at a predetermined speed with an optical image taken with theimaging sensor32 being displayed in color on themonitor13. The operator can observe the inside of thestomach51 of thepatient2 by observing this image. The operator can further readily control how the external magnetic field is applied so that the entire stomach region can be observed, using operating means such as a joystick provided outside the body while observing the observation image. The optical image can also be recorded in an unshown image recording device.
Following observation of thestomach51, the capsule-typemedical device1 is magnetically guided by the rotating magnetic field formed by themagnetic guiding device5 as described above, so as to pass from thestomach51 through the duodenum54, the small intestine and large intestine which are not shown, and to be extracted from the anus. During this time, the capsule-typemedical device1 can observe the interior of the entire digestive tract.
Due to the configuration of the present embodiment, the capsule-typemedical device1 can suppress useless motions of the capsulemain unit1A such as eccentric movement (zigzagging), enabling effective and smooth propulsion through the lumen to beside the target portion.
Also, no useless motions means that the magnetic guidance of the capsule-typemedical device1 is more effective, thus yielding the great advantage that one or both of themagnet36 within the capsule and the external magnet or electromagnet can be reduced in size.
Also, the medical acts can be completed in a short time by propelling the capsule-typemedical device1 smoothly and efficiently.
Also, the capsule-type medical device may be configured for spreading medicine, as shown inFIGS. 4A and 4B. That is to say, the capsule-typemedical device60 is configured having amedicine spreading opening61aprovided at the tip side so as to enable spreading of medicine stored in amedicine storing unit61 within the capsulemain unit60A.
Further, the capsule-typemedical device60 is configured to take body fluid samples. That is, the capsule-typemedical device60 is configured having a bodyfluid injecting opening62aon the rear end so as to take samples of body fluid into a bodyfluid storing unit62 within the capsulemain unit60A. Opening and closing of theopenings61aand62ais performed by communication control from thecontrol device3. Thus, the capsule-typemedical device60 is capable of discharging and spreading medicine stored in themedicine storing unit61 from themedicine spreading opening61ato a target portions, and also is capable of taking samples of body fluid from thefluid injecting opening62ainto the bodyfluid storing unit62.
Also, it is needless to say that themedicine storing unit61 may store a hemostatic agent for stopping bleeding, a ferrofluid or fluorescent agent which is safe to use with human bodies to externally determine hemorrhaging portions, and so forth, besides storing medicine.
Also, the capsule-typemedical device60 may be arranged to mix medicine stored in themedicine storing unit61 with the body fluid taken in from thefluid injecting opening62a,and ejecting and spreading this mixture from themedicine spreading opening61a.
Note that this capsule-typemedical device60 has aspiral portion37 formed on the outer perimeter of the capsule main unit, in the same way as with the capsule-typemedical device1 shown inFIG. 3A. Also, the capsule-typemedical device60 has the center of gravity thereof generally upon thelongitudinal center axis38.
Also, the capsule-typemedical device60 may be configured such that an elastic rubber cover having a spiral groove formed thereupon is detachably mounted to the capsule main unit as an exterior member, as shown inFIGS. 5A and 5B. That is to say, as shown inFIG. 5A, the capsule-typemedical device70 is configured such that anelastic rubber cover71 having spiral grooves69a(seeFIG. 5B) formed thereupon can be detachably mounted to the capsulemain unit70A. Thus, the capsule-typemedical device70 enables fluids such as gas and liquids in the body cavity to pass through the spiral grooves69aof theelastic rubber cover71 to the tip and rear sides thereof.
Also, the thick potions of theelastic rubber cover71 having a shape like a belt wound thereupon forms thespiral ridges69b,thus forming thespiral portion69.
The capsule-typemedical device70 has a treatmenttool storing portion72 capable of therapy or treatment within the capsulemain unit70A, and has a treatment tool opening72aformed on the tip thereof. This treatment tool opening72ais plugged with a soluble film such as gelatin which is digested by stomach fluid or a fatty acid which is digested by intestinal fluid, for example. The capsule-typemedical device70 is arranged to open the treatment tool opening72awhen reaching near the target portion.
Thetreatment tool73 stored in the treatmenttool storing portion72 is capable of extending the tip thereof from the treatment tool opening72aand retracting therein, and can perform therapy or treatment on the target portion of the body cavity tract. Thetreatment tool73 is operated and controlled by communication control from thecontrol device3. Specific operations of thetreatment tool73 may be carried out by operating means such as an unshown joystick or mouse or the like connected to the personal computermain unit11.
Note that inFIG. 5A, thetreatment tool73 shown is an injection needle capable of injecting a hemostatic agent. With the capsule-typemedical device70 in this case, upon confirmation of a hemorrhaging portion with an unshown blood sensor or theobservation device24, operations of thetreatment tool73 such as the hemostatic agent injection needle stored in the capsulemain unit70A are instructed by communication control from thecontrol device3, and a hemostatic agent such as ethanol or a powder medicine is spread onto the hemorrhaging portion, thereby stopping the bleeding.
Furthermore, the capsule-typemedical device70 comprises anultrasonic unit74 capable of examinations in the capsule main unit. Theultrasonic unit74 is configured of an unshown ultrasonic probe for transmitting and receiving ultrasonic waves and an ultrasonic control circuit for controlling and driving the ultrasonic probe.
The capsule-typemedical device70 has the ultrasonic probe disposed in a watertight manner such that an unshown acoustic lens unit is positioned on the outer face of the rear end of the capsulemain unit70A, such that a 360° ultrasonic tomographic image, for example, is obtained at the rear end side.
Then, with the capsule-typemedical device70, the ultrasonic tomographic image data obtained is modulated at the wireless transmission/reception circuit22 in the same manner as with the above-described observation image, and is emitted as radio waves from thewireless antenna21. Thus, the capsule-typemedical device70 is capable of diagnosing whether or not there are abnormalities in the depth-wise direction of deep portions in the body cavity wall, such as in thesmall intestine55 or the like. In the event that the capsule-typemedical device70 is configured to have theobservation device24 as well, both the surface and deep portions of the body cavity can be diagnosed at once.
Also, the capsule-typemedical device70 is configured with the capsulemain unit70A having connected thereto astring75 formed of soft plastic or the like, having sufficient softness, diameter, and strength, to allow the capsule-typemedical device70 to be extracted from the stomach or small intestine through the mouth, or the large intestine from the anus, following inspection, without damaging the mucous membranes in the body cavity. Thestring75 is formed in a soft fashion not to impede the rotational progress of the capsulemain unit70A. Thestring75 is used by fixing the base end outside of the body. Also, the center of gravity of the capsule-typemedical device70 generally is upon thecenter axis38 in the longitudinal direction of the capsulemain unit70A, as with inFIG. 3A and others.
The capsule-type medical device may be configured with thespiral portion37 and theobservation device24 provided at the rear side of the capsule main unit in the direction of procession.
That is to say, the capsule-typemedical device80 shown inFIGS. 6A and 6B comprises anexterior member80B having aspiral portion37 detachably formed on the rear side of the capsulemain unit80A in the direction of progression thereof (toward the left inFIG. 6A, in this case), as well as theobservation device24 along with theillumination device23 in the backwards direction as to the direction of progression of the capsulemain unit80A.
Also, the capsule-typemedical device81 shown inFIGS. 7A and 7B comprisesmultiple magnets36, and the magnets may be placed symmetrically across thelongitudinal center axis38 of the capsulemain unit81A. As with the capsule-typemedical device80, this capsule-typemedical device81 may be formed such that theexterior member81B provided with thespiral portion37 to the capsulemain unit81A is detachable.
Also, as shown inFIGS. 8A and 8B, the capsule-type medical device may be formed such that theexterior member83B provided with thespiral portion37 to the capsulemain unit83A in the direction of progression thereof is detachable. Further, theobservation device24 may be provided along with theillumination device23 in the backwards direction/as to the direction of progression of the capsulemain unit83A.
Now,reference numeral27B denotes a switch for tuning on and off electric power supplied from thebatteries26ain thebattery unit26.
The capsule-typemedical device83 shown inFIG. 8B has themagnet36 provided parallel to thelongitudinal center axis38 of the capsulemain unit83A. The capsule-typemedical device83 comprises the digitalsignal processing circuit25 and the wireless transmission/reception circuit22 below themagnet36.
Also, the capsule-typemedical device83 is arranged so as to be recovered by acapsule recovery tool86 inserted into a treatmenttool insertion channel85 of anendoscope84, as shown inFIGS. 9A and 9B.
Theendoscope84 is arranged so that thecapsule recovery tool86 can be inserted through the treatmenttool insertion channel85.Reference numeral87 denotes an observation device provided to adistal end84aof the insertion portion of theendoscope84. Thisobservation device87 is configured of an objectoptical system87aand animaging unit87bcomprising an imaging device provided at the imaging position of the objectoptical system87a.
Thecapsule recovery tool86 is formed as a flexible rod, with amagnet88 for recovering the capsule-typemedical device83 provided at the tip thereof. Thecapsule recovery tool86 also has a recessedportion89 formed such that thespiral portion37 of the capsulemain unit83A does not get in the way after the capsule-typemedical device83 is captured by themagnet88.
Also, an arrangement may be made wherein, as with the capsule-typemedical device90 shown inFIG. 10A, the capsulemain unit90A can be divided into the two portions of the portion where theobservation device24 is disposed, and the portion where themagnet36 and thespiral portion37 are provided. Thus, various combinations can be made for the capsule-typemedical device90 according to the use; an arrangement wherein the field of view of theobservation device24 is backwards as shown inFIG. 10A, an arrangement wherein the field of view of theobservation device24 is diagonally backwards as shown inFIG. 10B, and an arrangement wherein the field of view of theobservation device24 is sideways as shown inFIG. 10C.
Also, the capsule-type medical device may be arranged such that a portion having thespiral portion37 is formed of a flexible member such as elastic rubber or the like, as shown inFIG. 11A, so as to form a flexible insertion portion to be inserted into the body cavity.
That is, with the capsule-typemedical device100 as shown inFIG. 11A, the portion provided with thespiral portion37 may be formed as a flexible insertion portion (a flexible soft portion)101 formed of a long and small-diameter flexible member, provided at one end of the rigid capsule main unit10A, with twomagnets36aand36bsymmetrically disposed across thelongitudinal center axis38.
With this capsule-typemedical device100, theflexible insertion portion101 has the same outer diameter as the outer diameter of one end of the generally-cylindrical capsulemain unit100A to which it is fastened by screwing, and the tip (end) side of theflexible insertion portion101 is narrower than this outer diameter.
In this case, as shown inFIG. 11B, the capsule-typemedical device100 has theillumination device23 thereof configured of multiple LEDs disposed in a ring-like shape around theobservation device24.
Also, an arrangement may be made with a ring-shapedmagnet36, as with the capsule-typemedical device100′ having theflexible insertion portion101 as shown inFIGS. 12A and 12B. With this capsule-typemedical device100′, the base end of theflexible insertion portion101 is connected to the rigid capsulemain unit100A by fitting or pressing.
Also, instead of providing thespiral portion37 on theflexible insertion portion101, an arrangement may be made wherein thespiral portion37 is provided on the rigid portion toward the rear on the side opposite to theflexible insertion portion101 to which theflexible insertion portion101 is connected (in the event that theflexible insertion portion101 is at the front in the direction of advancing), as with theflexible insertion portion101 as with the capsule-typemedical device110 shown inFIGS. 13A through 13C. InFIGS. 13A through 13C, the direction of advancing to the left, and the right side is the rear. The capsule-type medical device is swallowed, or inserted from the anus into the large intestine, so as to head in the direction of advancing.
In this case, various combinations can be made for the capsule-typemedical device110 according to the use; an arrangement wherein the field of view of theobservation device24 is backwards as shown inFIG. 13A, an arrangement wherein the field of view of theobservation device24 is diagonally backwards as shown inFIG. 13B, and an arrangement wherein the field of view of theobservation device24 is sideways as shown inFIG. 13C. That is to say, theflexible insertion portion101 and the rigid capsulemain unit110A are separable.
With the capsule-typemedical device110 shown inFIG. 13A, thespiral portion37 is provided over almost the entire perimeter of the rear side of the capsulemain unit110A. Also, with the capsule-typemedical device110 shown inFIG. 13B, thespiral portion37 is provided over half of the rear side of the capsulemain unit110A in a diagonal manner, so as to allow observation in the diagonally backwards direction. Also, with the capsule-typemedical device110 shown inFIG. 13C, thespiral portion37 is provided over half of the rear side of the capsulemain unit110A, so as to allow sideways observation.
Also, the capsule-type medical device may have a configuration wherein the flexible insertion portion is detachably mountable to the capsule main unit as shown inFIG. 14A. That is to say, with the capsule-typemedical device120 shown inFIG. 14A, theflexible insertion portion121 is detachably mountable to the capsulemain unit120A.
Theflexible insertion portion121 is soft, and thus easily bendable as shown inFIG. 14B. Theflexible insertion portion121 has a structure which is not readily stretched or compressed in the longitudinal direction, but readily bends in the direction generally orthogonal to the longitudinal direction.
Note that though the present embodiment has awireless antenna21 for performing transmission and reception with thecontrol device3, thus configuring a capsule-type medical device capable of examination, therapy, and/or treatment by passing through the body cavity under the control of thecontrol device3, the present invention is by no means restricted to this arrangement, and rather may be formed as a capsule-type medical device which is not provided with awireless antenna21 and wherein information (data) such as optical images are extracted following passing through the body cavity tract and being recovered outside of the body.
Second Embodiment A second embodiment of the present invention will be described with reference toFIGS. 15 through 21. The present embodiment has been made to serve the same purpose as that of the first embodiment. The present embodiment also aims to pass through bent body cavity portions more smoothly.
The second embodiment comprises a flexible insertion portion (flexible soft portion), detachably mounted to a rigid capsule main unit. Other configurations are approximately the same as the first embodiment, so the same components will be denoted with the same reference numerals, and detailed description thereof will be omitted.
With the capsule-typemedical device150 according to the second embodiment as shown inFIG. 15, the bendableflexible insertion portion151 is formed so as to be even longer and smaller in diameter than theflexible insertion portion101 shown inFIG. 11A, for example, and is detachably mounted to the rigid capsulemain unit150A.
Theflexible insertion portion151 formed of elastic rubber or the like has themagnet36 built in so as to be positioned on thelongitudinal center axis38, and has on the base side thereof a mountingportion151aso as to be mounted onto the capsulemain unit150A. Theflexible insertion portion151 is mounted onto the capsulemain unit150A, thus configuring the capsule-typemedical device150.
In this case, the diameter Da of a recessed portion provided on the mountingportion151aat the base side of theflexible insertion portion151 is smaller than the diameter Db of the capsulemain unit150A, so that this recessed portion can be elastically attached to the capsulemain unit150A.
Also, the capsule-typemedical device150 is configured with the center of gravity G thereof generally matching thelongitudinal center axis38 of the capsulemain unit150A, as with the first embodiment (seeFIG. 16).
Also, as with the case of theflexible insertion portion101, theflexible insertion portion151 is configured so as to be bendable in the direction orthogonal to the longitudinal direction, with the side portion thereof being formed smaller in diameter than the outer diameter of the capsulemain unit150A, so as to have functions of bending following the bending body cavity tract such that the capsulemain unit150A at the rear end can smoothly proceed, as specifically indicated inFIG. 18.
Accordingly, the capsule-typemedical device150 moves through the body cavity with theflexible insertion portion151 exploring the way to proceed, as shown inFIG. 16.
Now, the capsule-typemedical device150 may be configured so that, with regard to the maximum diameter L of a lumen organ such as the large intestine or the like, the relation between the rigid length L1 of the rigid capsulemain unit150A and the soft length L2 of the softflexible insertion portion151 is in the range of L1<L<L1+L2 as shown inFIG. 17.
In this case, the capsule-typemedical device150 is longer than the maximum diameter L of the lumen organ and moreover the length of the rigid portion is short, so the direction thereof does not change in the lumen, and further, rotations from themagnet36 are converted directly into propulsion, so the rotational force can be efficiently converted into propulsion, and smoothly move through the lumen.
Also, the capsule-typemedical device150 rotates due to themagnet36 at bent and narrow portions in the lumen such as the small intestine and large intestine as shown inFIG. 18, with theflexible insertion portion151 finding its way ahead, and the capsulemain unit150A following theflexible insertion portion151 can readily pass through, as well.
Accordingly, with the present embodiment, eccentric movement can be suppressed, and the capsule-typemedical device150 can be smoothly propelled to the target portion, as with the first embodiment. In this case, theflexible insertion portion151 is formed even longer and smaller in diameter, so eccentric movement can be suppressed even further.
With the present embodiment, theflexible insertion portion151 at the tip bends following the shape of bent tract in the lumen, and thus acts to allow the trailing capsulemain unit150A to change direction so as to smoothly pass. The capsule-typemedical device150 thus smoothly passes through bent lumen portions as well, thereby reducing the time for medical examination and/or treatment.
Also, an arrangement may be made wherein a wire-like member162 is fixed by adhesions to the outer perimeter of theflexible insertion portion161 to form thespiral portion37, as with the capsule-typemedical device160 shown inFIG. 19. With such an arrangement for the capsule-typemedical device160, thespiral portion37 can be readily provided to theflexible insertion portion161. The wire-like member162 may be formed of an elastic member such as rubber, shaped into a wire-like form.
Also, an arrangement may be made for the capsule-typemedical device170 wherein multiple ball-shapedmagnets172aare built into theflexible insertion portion171 so as to form multiple ball-shapedprotrusions172, as shown inFIG. 20. Theflexible insertion portion171 is soft, so the capsule-typemedical device170 can go to the depths of bent portions in the tubular organs such as the small intestine or large intestine, while rotating, as indicated inFIG. 21.
Third Embodiment A third embodiment of the present invention will be described with reference toFIGS. 22 and 23. The primary objects of the present embodiment are approximately the same as those of the first and second embodiments. Also, the present embodiment also aims to enable medical examination and/or treatment to be performed even more efficiently.
With the third embodiment, two capsule main units are provided, a leading-side rigid portion and a trailing-side rigid portion, with the two rigid portions being connected with a string-like material covered with a soft elastic materials such as urethane or silicon rubber or the like which smoothly changes external form as shown in the drawings, for example. Other configurations are approximately the same as the first embodiment, so the same components will be denoted with the same reference numerals, and detailed description thereof will be omitted.
With the capsule-typemedical device200 according to the third embodiment, two capsule main units200A are provided, a leading-siderigid portion201 and a trailing-siderigid portion202, with the tworigid portions201 and202 being connected with a string-like member203 as shown inFIG. 22. Also, the capsule-typemedical device200 is configured with the center of gravity G thereof generally matching thelongitudinal center axis38 of the capsule main unit200A, as with the first embodiment.
Also, the capsule-typemedical device200 comprises thespiral portions37 on both the leading-siderigid portion201 and the trailing-siderigid portion202. Further, theobservation device24 is configured so as to have a field of view looking diagonally forwards at the tip of the trailing-siderigid portion202.
According to such a configuration, the capsule-typemedical device200 can obtain a good observation field of view even if in close contact with the lumen.
That is to say, the capsule-typemedical device200 proceeds while rotating, so the inner walls can be efficiently observed, and medical examination and/or treatment can be performed efficiently.
Also, with the capsule-typemedical device200, a portion of the protrusions formed on the leading-siderigid portion201 also come into the field of view of theobservation device24, so a mark is made in this field of view to indicate the position (polarity) of themagnet36.
Also, an arrangement may be made for the capsule-typemedical device210 whereinmagnets36,observation devices24, andillumination devices23, are provided to both the leading-siderigid portion201 and trailing-siderigid portion202 provided with thespiral portions37. In this case, propulsion can be generated for the capsule-typemedical device210 as long as one of thespiral portions37 comes into contact with the inner walls of the lumen or with luminal fluids, regardless of whether theother spiral portion37 is in contact with something.
This means that the capsule-typemedical device210 can be propelled efficiently, and medical examination and/or treatment can be performed efficiently. Also, providing observation means on both sides allows medical examination and/or treatment (image-taking, in this case) to be performed even in the event that the image from one is insufficient, by compensating with the image from the other. In order to expand this function, an arrangement may be made wherein the observation and illumination range of theobservation devices24 andillumination devices23 of the trailing-siderigid portion202 is changed as to the observation and illumination range of theobservation devices24 andillumination devices23 of the leading-siderigid portion201, for example, widening the range as indicated by the dotted lines (only the range of observation is indicated, for sake of simplicity).
In this case, two types of imaged pictures with different observation ranges are obtained, so medical examination and/or treatment can be performed more efficiently.
According to the present invention described above, a capsule-type medical device which can smoothly reach a target position through the lumen tract without useless motions such as eccentric movement can be realized. Further, according to the present invention, magnetic guiding efficiency is improved by reducing the unnecessary movement, so a capsule-type medical device wherein one or both of the magnet within the capsule main unit and the external magnet can be reduced in size.
Having described the preferred embodiments of the invention referring to the accompanying drawings, it should be understood that the present invention is not limited to those precise embodiments, and various changes, combinations, and modifications thereof could be made by one skilled in the art without departing form the spirit or scope of the invention as defined in the appended claims.