US20110137121A1 - Endoscope apparatus - Google Patents

Abstract

The endoscope applicator according to the present invention allows lubricant to be supplied uniformly to the entire inner surface of the endoscope applicator without increasing the diameter of the endoscope applicator because the lubricant supply path is laid on the outer surface of the endoscope applicator extending from the base end portion to the tip portion of the endoscope applicator and a plurality of openings are formed in the lubricant supply path and endoscope applicator at predetermined intervals in such a way that their opening areas of the opening increase from the base end portion to the tip portion. Moreover, the endoscope apparatus according to the present invention can improve the maneuverability of the insert portion and applicator during pull-in operation. Furthermore, the endoscope apparatus according to the present invention makes it possible to determine pull-out force quantitatively.

Description

BACKGROUND OF THE INVENTION
• 1. Field of the Invention
• The present invention relates to an endoscope applicator and endoscope apparatus. More particularly, it relates to an endoscope applicator for use to insert an insert portion of an endoscope into a body cavity as well as to an endoscope apparatus which uses the applicator.
• 2. Description of the Related Art
• When inserting an insert portion of an endoscope into a deep digestive tract such as a small intestine, it is difficult to insert the insert portion into the depth by simply pushing the insert portion because the force is not transmitted readily to the tip of the insert portion due to complicated bends in the intestinal tract. To deal with this situation, an endoscope apparatus has been proposed which inserts the insert portion of the endoscope into the body cavity by fitting an applicator called an overtube or sliding tube over the insert portion, guides the insert portion by the applicator, and thereby prevents excess bending and flexion of the insert portion (e.g., Japanese Patent Application Laid-open No. 10-248794). Incidentally the overtube is an applicator used in the small intestine while the sliding tube is an applicator used in the large intestine.
• Also, it has been proposed to form a lubricant inlet at a base end portion of the conventional overtube, pour lubricant through the inlet into the base end portion of the overtube, and thereby improve slidability of the endoscope insert portion along the overtube, reducing the time required for endoscopic procedures. Water, a physiological salt solution, or the like is used as the lubricant.
• Furthermore, known endoscope apparatus include double-balloon endoscope apparatus which have a first balloon at a tip portion of the endoscope insert portion and a second balloon at a tip of portion the applicator (e.g., Japanese Patent Application Laid-open Nos. 2001-340462 and 2002-301019).
• With a double-balloon endoscope apparatus, the bent intestinal tract is sometimes contracted in a straightened state by inserting a predetermined length of the insert portion and applicator in the intestinal tract, inflating the two balloons, and pulling in the insert portion and applicator simultaneously with the two balloons placed in intimate contact with intestinal walls. Subsequently, the insert portion and applicator are pushed and pulled repeatedly to draw up the intestinal tract and put the insert portion in a desired site. In the pull-in operation, the physician grips the applicator made of an elastic member, thereby bringing it into intimate contact with the insert portion by elastic deformation, and pulls in the applicator, thereby pulling in the insert portion at the same time by means of frictional resistance between the applicator and insert portion (e.g., Japanese Patent Application Laid-open No. 10-248794).
• When the inflated first balloon or second balloon comes into too intimate contact with, or adheres to, intestinal walls, if the physician pulls in (pull out) the insert portion and overtube forcibly, the intestinal walls may be damaged. In such a case, i.e., if the physician feels a strong pull-out resistance, conventionally he/she lowers the adhesive force by rotating the overtube or insert portion before resuming the pull-in operation.
SUMMARY OF THE INVENTION
• However, there is a problem: in the case of the conventional overtube with a lubricant inlet formed at the base end portion, the lubricant poured through the inlet is not distributed sufficiently over the entire inner surface of the overtube, and thus it is not possible to further improve slidability of the endoscope insert portion.
• This problem can be solved if the diameter of the overtube is enlarged, increasing the clearance between the overtube and endoscope insert portion and thereby allowing the lubricant supplied to the base end portion to be distributed over the entire inner surface of the overtube. However, since the overtube is inserted in the body cavity, preferably its diameter is minimized. This poses a dilemma: decreasing the diameter of the overtube makes it impossible to distribute the lubricant over the entire inner surface of the overtube while increasing the diameter of the overtube makes the overtube unsuitable as a member to be inserted in the body cavity.
• The conventional double-balloon endoscope apparatus have the disadvantage of poor maneuverability because the insert portion tends to slip along the applicator during the pull-in operation.
• Moreover, conventionally the physician determines his/her subsequent action (whether to continue pulling in the insert portion and overtube or rotate the insert portion and overtube) upon encountering a pull-out resistance. Consequently, there has been a demand for an endoscope apparatus which makes it possible to quantitatively determine the pull-out resistance produced when the insert portion and applicator are pulled in and perform subsequent operations properly.
• The present invention has been made in view of the above circumstances and has an object to provide an endoscope applicator which allows lubricant to be supplied uniformly to the entire inner surface of the applicator without increasing the diameter of the applicator.
• The present invention has been made in view of the above circumstances and has another object to provide an endoscope apparatus which can improve the maneuverability of an insert portion and applicator when they are pulled in.
• The present invention has been made in view of the above circumstances and has another object to provide an endoscope apparatus which allows the pull-out resistance of an applicator or overtube, and an insert portion to be determined quantitatively.
• To achieve the above objects, a first aspect of the present invention provides an endoscope applicator which allows an endoscope insert portion to be inserted through a base end portion of the endoscope applicator and allows lubricant to be poured through a lubricant inlet formed at the base end portion, wherein a lubricant supply path is formed in the endoscope applicator to allow the lubricant supplied to the lubricant inlet to be supplied to a clearance between an inner surface of the endoscope applicator and an outer surface of the endoscope insert portion.
• The first aspect of the present invention has been made in view of the fact that between the endoscope insert portion and the endoscope applicator, the part which particularly needs enhanced lubricity is the tip portion of the endoscope applicator where the endoscope insert portion is rubbed by an inner edge of an opening portion at the tip of the applicator. As described in the first aspect, by forming a lubricant supply path in the endoscope applicator to allow the lubricant supplied to the lubricant inlet to be supplied to a clearance between an inner surface of the endoscope applicator and an outer surface of the endoscope insert portion, it is possible to supply the lubricant directly to the tip portion of the endoscope applicator. Thus, the present invention can improve the lubricity of the part which particularly needs enhanced lubricity.
• A second aspect of the present invention provides the endoscope applicator according to the first aspect, wherein a plurality of openings are formed in the endoscope applicator at predetermined intervals to supply the lubricant poured into the lubricant supply path to the inside of the endoscope applicator. A third aspect of the present invention provides the endoscope applicator according to the second aspect, wherein opening areas of the plurality of openings increase from base end portion to tip portion of the endoscope applicator.
• According to the second aspect of the present invention, the lubricant poured through the lubricant inlet flows to the lubricant supply path, and is subsequently supplied to the inside of the endoscope applicator via the plurality of openings formed in the applicator. Since the plurality of openings are formed from the base end portion to the tip portion of the endoscope applicator at predetermined intervals, the lubricant is supplied to the entire inner surface of the endoscope applicator. Furthermore, as described in the third aspect of the present invention, since the opening areas of the openings increase from the base end portion to the tip portion of the endoscope applicator, a uniform amount of lubricant is supplied over the entire inner surface of the endoscope applicator. Thus, the present invention allows lubricant to be supplied uniformly to the entire inner surface of the endoscope applicator without increasing the diameter of the endoscope applicator. This constantly provides good sliding characteristics, and thereby improves slidability of the insert portion along the endoscope applicator, reducing the time required for endoscopic procedures. Also, since good sliding characteristics are obtained constantly, it is possible to provide an endoscope applicator of a small diameter by decreasing the inside and outside diameters of the endoscope applicator and reducing the inside diameter of the endoscope applicator close to the diameter of the endoscope insert portion.
• A fourth aspect of the present invention provides the endoscope applicator according to the third aspect, wherein a plurality of lubricant supply paths are provided. By providing a plurality of lubricant supply paths in the endoscope applicator, it is possible to form a plurality of openings on the circumference of the applicator, and thereby supply a more uniform amount of lubricant over the entire inner surface of the endoscope applicator.
• A fifth aspect of the present invention provides the endoscope applicator according to the fourth aspect, wherein the lubricant supply path is installed spirally on the outer surface of the endoscope applicator. This makes it possible to form a plurality of openings on the circumference of the endoscope applicator using the single lubricant supply path, allowing lubricant to be supplied more uniformly to the entire inner surface of the endoscope applicator than when a single straight lubricant supply path is used.
• To achieve the above objects, a sixth aspect of the present invention provides an endoscope apparatus, comprising: an endoscope with a balloon attached to a tip portion of an insert portion; and an applicator through which the insert portion of the endoscope is inserted into a body cavity, wherein an inner surface of the applicator is equipped with an engaging portion which engages with an outer surface of the insert portion when the applicator is squeezed and deformed.
• According to the sixth aspect of the present invention, the inner surface of the applicator is equipped with an engaging member which engages with the outer surface of the insert portion to prevent relative slippage of the insert portion along the applicator when the applicator is squeezed and deformed elastically in such a direction as to reduce the diameter. Therefore, it is possible to prevent the insert portion from slipping along the applicator during pull-in operation. This improves the maneuverability of the insert portion and applicator when they are pulled in. The engaging member engages with the outer surface of the insert portion only when the applicator is deformed elastically, and the applicator is not deformed elastically when the insert portion is inserted and withdrawn into/from the applicator. Thus, the insertion/withdrawal operation is not affected adversely.
• A seventh aspect of the present invention provides the endoscope apparatus according to the sixth aspect, wherein the outer surface of the insert portion is equipped with an engaged portion which is engaged with the engaging portion of the applicator. By forming the engaged member in the insert portion, it is possible to prevent slippage reliably and further improve maneuverability.
• To achieve the above objects, an eighth aspect of the present invention provides an endoscope apparatus, comprising: an endoscope with a balloon attached to a tip portion of an insert portion; and an applicator through which the insert portion of the endoscope is inserted into a body cavity, wherein at least one of the insert portion and the applicator is equipped with a pull-out force measuring device which measures pull-out force of the insert portion or applicator. Since the insert portion or applicator is equipped with the pull-out force measuring device which measures the pull-out force of the insert portion or applicator, it is possible to determine the pull-out force quantitatively.
• A ninth aspect of the present invention provides the endoscope apparatus according to the eighth aspect, further comprising a balloon pressure adjusting device which reduces internal pressure of the balloon when the pull-out force measured by the pull-out force measuring device exceeds a predetermined value. Since the internal pressure of the balloon is reduced by the balloon pressure adjusting device when the pull-out force measured by the pull-out force measuring device exceeds a predetermined value, it is possible to reduce frictional force between the balloon and intestinal walls, and thereby prevent damage to the intestinal walls. To adjust the internal pressure of the balloon by the balloon pressure adjusting device, it only needs to lower the internal pressure, and the easiest method in terms of control involves, for example, reducing the internal pressure by simply releasing air from the balloon.
• A tenth aspect of the present invention provides an endoscope apparatus, comprising: an endoscope with a first balloon attached to a tip portion of an insert portion; and an overtube whose tip is equipped with a second balloon and through which the insert portion of the endoscope is inserted into a body cavity, wherein at least one of the insert portion and the overtube is equipped with a pull-out force measuring device which measures pull-out force of the insert portion or overtube. Since the insert portion or overtube is equipped with the pull-out force measuring device which measures the pull-out force of the insert portion or overtube, it is possible to determine the pull-out force quantitatively.
• An eleventh aspect of the present invention provides the endoscope apparatus according to the tenth aspect, further comprising a balloon pressure adjusting device which reduces internal pressure of at least one of the first balloon and the second balloon when the pull-out force measured by the pull-out force measuring device exceeds a predetermined value. Since the internal pressure of the first balloon and/or second balloon is reduced by the balloon pressure adjusting device when the pull-out force measured by the pull-out force measuring device exceeds a predetermined value, it is possible to reduce frictional force between the balloons and intestinal walls, and thereby prevent damage to the intestinal walls. To adjust the internal pressure of the first balloon and/or second balloon by the balloon pressure adjusting device, it only needs to lower the internal pressure, and the easiest method in terms of control involves, for example, reducing the internal pressure by simply releasing air from the first balloon and/or second balloon.
• According to a twelfth aspect of the present invention, the pull-out force measuring device is a strain gauge. Since the use of a strain gauge as the pull-out force measuring device makes it possible to detect minute strain in the insert portion, applicator, and overtube as an electrical signal and display it as electrical resistance, it is possible to determine the pull-out force quantitatively.
• As described above, in the endoscope applicator according to the present invention, the lubricant supply path is laid on the outer surface of the applicator extending from the base end portion to the tip portion of the applicator and a plurality of openings are formed in the lubricant supply path and applicator at predetermined intervals in such a way that their opening areas of the opening increase from the base end portion to the tip portion. Therefore, the endoscope applicator allows lubricant to be supplied uniformly to the entire inner surface of the applicator without increasing the diameter of the applicator.
• Moreover, in the endoscope apparatus according to the present invention, an engaging portion which engages with the outer surface of the insert portion is provided on the inner surface of the applicator when the applicator is squeezed and deformed. Therefore, it is possible to prevent the insert portion from slipping along the applicator during pull-in operation and thereby the maneuverability of the insert portion and applicator during pull-in operation is improved.
• Furthermore, in the endoscope apparatus according to the present invention, the insert portion, applicator, and/or overtube are equipped with the pull-out force measuring device which measures the pull-out force of the insert portion, applicator, and/or overtube. Therefore, it is possible to determine pull-out force quantitatively.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a system block diagram of an endoscope apparatus which employs an overtube according to the present invention;
• FIG. 2 is a perspective view showing a tip portion of an insert portion of an endoscope;
• FIG. 3 is a perspective view showing a rigid tip portion of an insert portion equipped with a first balloon;
• FIG. 4 is a sectional side view showing a tip portion of an overtube with an insert portion passed through it;
• FIGS. 5A and 5B are enlarged sectional views of the essence part of a lubricant supply path formed in a tube body;
• FIG. 6 is a sectional view of a tube body in which a plurality of lubricant supply paths are formed;
• FIGS. 7A and 7B are explanatory diagrams illustrating an example in which a spiral lubricant supply path is formed on a tube body;
• FIGS. 8A to 8H are explanatory diagrams illustrating how to operate the endoscope apparatus shown inFIG. 1;
• FIG. 9 is a sectional view of an overtube whose tip portion is supplied with a lubricant;
• FIG. 10 is a system block diagram of an endoscope apparatus according to an embodiment the present invention;
• FIG. 11 is a perspective view showing a tip portion of an insert portion of an endoscope;
• FIG. 12 is a perspective view showing a rigid tip portion of an insert portion equipped with a first balloon;
• FIG. 13 is a sectional side view showing a tip portion of an overtube with an insert portion passed through it;
• FIG. 14 is an explanatory diagram illustrating essential part, where antiskid members are formed on both overtube and insert portion;
• FIG. 15 is an explanatory diagram illustrating essential part, where antiskid members are engaged with each other;
• FIGS. 16A to 16H are explanatory diagrams illustrating how to operate the endoscope apparatus shown inFIG. 10;
• FIG. 17 is a system block diagram of an endoscope apparatus according to an embodiment the present invention;
• FIG. 18 is a perspective view showing a tip portion of an insert portion of an endoscope;
• FIG. 19 is a perspective view showing a tip portion of an insert portion equipped with a first balloon;
• FIG. 20 is a sectional side view of an overtube with an insert portion passed through it;
• FIG. 21 is a block diagram showing configuration of a balloon pressure regulating device which reduces the internal pressure of a balloon; and
• FIGS. 22A to 22H are explanatory diagrams illustrating how to operate the endoscope apparatus shown inFIG. 17.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
• Preferred embodiments of an endoscope applicator and endoscope apparatus according to the present invention will be described with reference to the accompanying drawings.
• FIG. 1 is a system block diagram of an endoscope apparatus which employs an endoscope applicator according to the present invention. The endoscope apparatus shown in the figure comprises anendoscope10, overtube (applicator)50, andballoon control apparatus100.
• Theendoscope10 is equipped with ahand controller14 and aninsert portion12 provided in a row arrangement with thehand controller14. Thehand controller14 is connected with auniversal cable15 whose tip is equipped with a connector (not shown) to be connected with a processor or light source (not shown).
• Thehand controller14 is equipped with an air/water feed button16, anaspiration button18, and anshutter button20, which are provided in proximity in a row arrangement and operated by the physician. Also, it is equipped with a pair of angle knobs22 and aforceps inlet24, which are placed at predetermined locations. Furthermore, thehand controller14 is equipped with a balloonair feed port26 to supply and suck air to/from afirst balloon30.
• Theinsert portion12 consists of asoft portion32, aflexible portion34, and arigid tip portion36. Theflexible portion34 is constructed from a plurality of joint rings connected flexibly. It is flexed remotely through rotation of the pair of angle knobs22 mounted on thehand controller14. This makes it possible to orient atip surface37 of atip portion36 in a desired direction.
• As shown inFIG. 2, an objectiveoptical system38, anillumination lens40, an air/water supply nozzle42, aforceps port44, etc. are mounted at predetermined locations on thetip surface37 of thetip portion36. Also, an air supply/suction port28 opens to the outer surface of thetip portion36. The air supply/suction port28 is communicated with the balloonair feed port26 inFIG. 1 via an air supply tube (not shown) which is approximately 0.8 mm in inside diameter and which is passed through theinsert portion12. Consequently, when air is fed to the balloonair feed port26, the air supply/suction port28 in thetip portion36 emits air. When air is sucked through the balloonair feed port26, the air supply/suction port28 sucks air.
• As shown inFIG. 1, thefirst balloon30 made of an elastic body such as rubber is detachably attached to thetip portion36 of theinsert portion12. As shown inFIG. 3, thefirst balloon30 has aninflatable portion30cin the center and mountingportions30aand30bon both ends. It is attached to thetip portion36 in such a way that the air supply/suction port28 is located on the inner side of theinflatable portion30c. The mountingportions30aand30bhave smaller diameters than thetip portion36. They are brought into intimate contact with thetip portion36 by their own elastic force and then fastened by a thread (not shown) wound around them. The fastening method is not limited to the use of a thread, and the mountingportions30aand30bmay be fastened to thetip portion36 by fitting retainer rings or rubber bands over the mountingportions30aand30b.
• Of thefirst balloon30 attached to thetip portion36, theinflatable portion30cis inflated into an approximately spherical shape by air supplied through the air supply/suction port28 shown inFIG. 2. When air is sucked through the air supply/suction port28, theinflatable portion30cis deflated and brought into intimate contact with the outer surface of thetip portion36.
• Theovertube50 shown inFIG. 1 has atube body51 andgrip portion52. As shown inFIG. 4, thetube body51 is tubular in shape and has an inside diameter slightly larger than the outside diameter of theinsert portion12. Also, thetube body51 is a molding of flexible urethane resin. Its inner and outer surfaces are covered with a lubricious coating. Aconnection port52A formed at the tip of arigid grip portion52 is fitted watertight into a base end opening51A of thetube body51 to detachably connect thegrip portion52 to thetube body51. Incidentally, theinsert portion12 is inserted into thetube body51 through a base end opening52B of thegrip portion52.
• As shown inFIG. 1, a balloonair feed port54 is provided at the base end of thetube body51. The balloonair feed port54 is connected with anair supply tube56 approximately 1 mm in inside diameter. Being bonded to the outer surface of thetube body51, theair supply tube56 extends to the tip portion of thetube body51 as shown inFIG. 4.
• Atip58 of thetube body51 is tapered. Asecond balloon60 made of an elastic body such as rubber is attached to the base end of thetip58 of thetube body51 in such a way as to be penetrated by thetube body51. It has aninflatable portion60cin the center and mountingportions60aand60bon both ends. The mountingportion60aon the tip side is folded back into theinflatable portion60cand fastened to thetube body51, being wound by aradiopaque thread62. The mountingportion60bon the base end side is placed outside thesecond balloon60 and fastened to thetube body51, being wound by athread64.
• Theinflatable portion60chas an approximately spherical shape in normal state (when neither inflated nor deflated) and is larger than thefirst balloon30 in normal state (when neither inflated nor deflated). Thus, when air is fed to thefirst balloon30 and thesecond balloon60 at the same pressure, theinflatable portion60cof thesecond balloon60 becomes larger in outside diameter than theinflatable portion30cof thefirst balloon30. For example, when the outside diameter of thefirst balloon30 is 25 mm, the outside diameter of thesecond balloon60 is 50 mm.
• Theair supply tube56 opens into theinflatable portion60cby forming an air supply/suction port57. Thus, when air is fed through the balloonair feed port54, it blows out of the air supply/suction port57 to inflate theinflatable portion60c. On the other hand, when air is sucked out of the balloonair feed port54, it is sucked through the air supply/suction port57, deflating thesecond balloon60.
• Theovertube50 has alubricant inlet66, which is connected to alubricant supply path68. Thelubricant supply path68 is laid along the axis of thetube body51, extending from the base end portion to the tip portion of thetube body51 as shown inFIGS. 1 and 4. Also, a plurality ofopenings75 are formed at predetermined intervals in thelubricant supply path68 and thetube body51 as shown inFIG. 4 to supply the lubricant poured into thelubricant supply path68 to inside thetube body51. Theopenings75 are formed in such a way that their opening areas increase from the base end portion to the tip portion of thetube body51. The intervals and opening areas of theopenings75 are determined according to the amount of lubricant supplied from alubricant supply portion72, such as a syringe shown inFIG. 1, connected to theinlet66. That is, the intervals and opening areas which will allow lubricant to be supplied uniformly to the entire inner surface of thetube body51 are determined based on the amount of lubricant supply. Alternatively, the amount of lubricant supply may be determined based on the intervals and opening areas of theopenings75.
• FIGS. 5A and 5B show an example of a manufacturing method of thelubricant supply path68.FIGS. 5A and 5B are enlarged views of a portion near thelubricant supply path68 with thetube body51 cut along a plane orthogonal to the axial direction. As shown inFIG. 5A, agutter member74 with a U-shaped cross section is formed integrally with thetube body51 and anopening75 is formed in it by a subsequent process. A urethane-based heat-shrinkable sheet ortube76 is put over thegutter member74 ortube body51 and is heat shrunk. This produces alubricant supply path68 made of thegutter member74 and heat-shrinkable sheet ortube76 as shown inFIG. 5B. Alternatively, thelubricant supply path68 may be formed integrally with thetube body51 in such a way as to be buried in the latter.
• A plurality oflubricant supply paths68 may be formed on the outer surface of thetube body51 as shown inFIG. 6 (three lubricant supply paths inFIG. 6). It is possible to bond aseparate gutter member74 to thetube body51 instead of forming thegutter member74 integrally with thetube body51, createopenings75, and heat-shrink a heat-shrinkable sheet ortube76 to form alubricant supply path68 as shown inFIGS. 5A and 5B. Furthermore, it is possible to form or bond agutter member74 spirally around thetube body51 as shown inFIG. 7A and heat-shrink a heat-shrinkable sheet ortube76 to form alubricant supply path68 as shown inFIG. 7B. InFIGS. 7A and 7B again, theopenings75 are formed in such a way that their opening areas increase gradually from the base end portion to the tip portion of thetube body51.
• On the other hand, theballoon control apparatus100 inFIG. 1 supplies and sucks a fluid such as air to/from thefirst balloon30 as well as thesecond balloon60. Theballoon control apparatus100 includes anapparatus body102 equipped with a pump, sequencer, etc. (not shown) and a remotecontrol hand switch104.
• A power switch SW1, a stop switch SW2, apressure gauge106 for thefirst balloon30, and apressure gauge108 for thesecond balloon60 are installed on a front panel of theapparatus body102. Also, atube110 for use to supply and suck air to/from thefirst balloon30 and atube120 for use to supply and suck air to/from thesecond balloon60 are installed on the front panel of theapparatus body102. Thetubes110 and120 haveliquid reservoir tanks130 and140, respectively, to collect liquid flowing backward from thefirst balloon30 andsecond balloon60 in case thefirst balloon30 and thesecond balloon60 burst, respectively.
• Thehand switch104 contains a stop switch SW3 similar to the stop switch SW2 of theapparatus body102, an ON/OFF switch SW4 for pressurization/depressurization of thefirst balloon30, a pause switch SW5 for use to maintain the pressure of thefirst balloon30, an ON/OFF switch SW6 for pressurization/depressurization of thesecond balloon60, and pause switch SW7 for use to maintain the pressure of thesecond balloon60. Thehand switch104 is electrically connected to theapparatus body102 via a cable150.
• Being configured as described above, theballoon control apparatus100 inflates thefirst balloon30 and thesecond balloon60 by supplying air to them and keeps thefirst balloon30 and thesecond balloon60 inflated by maintaining the air pressure at a fixed value. Also, it deflates thefirst balloon30 and thesecond balloon60 by sucking air from them and keeps thefirst balloon30 and thesecond balloon60 deflated by maintaining the air pressure at a fixed value.
• Next, an operation method of the endoscope apparatus will be described with reference toFIGS. 8A to 8H.
• First, as shown inFIG. 8A, theinsert portion12 is inserted in an intestinal tract (e.g., pars descendens duodeni)70 with theovertube50 put over theinsert portion12. At this time, thefirst balloon30 and thesecond balloon60 are kept deflated.
• Next, as shown inFIG. 8B, with thetip58 of theovertube50 inserted to a bend of theintestinal tract70, thesecond balloon60 is inflated by air supplied to it. Consequently, thesecond balloon60 is restrained by theintestinal tract70 and thetip58 of theovertube50 is fixed to theintestinal tract70.
• Next, as shown inFIG. 8C, only theinsert portion12 of theendoscope10 is inserted into the depth of theintestinal tract70. Then, as shown inFIG. 8D, thefirst balloon30 is inflated by air supplied to it. Consequently, thefirst balloon30 is fixed to theintestinal tract70. Since thefirst balloon30 is smaller than thesecond balloon60 when inflated, there is less strain on theintestinal tract70. This prevents damage to theintestinal tract70.
• Next, after thesecond balloon60 is deflated with air sucked from it, theovertube50 is pushed in and inserted together with theinsert portion12 as shown inFIG. 8E. When thetip58 of theovertube50 is inserted to near thefirst balloon30, thesecond balloon60 is inflated with air supplied to it as shown inFIG. 8F. Consequently, thesecond balloon60 is fixed to theintestinal tract70. That is, theintestinal tract70 is held by thesecond balloon60.
• Then, as shown inFIG. 8G, theovertube50 is pulled in. This causes theintestinal tract70 to contract in a straightened state, eliminating excess bending and flexion of theovertube50. Incidentally, when theovertube50 is pulled in, thefirst balloon30 and thesecond balloon60 are restrained by theintestinal tract70, and the frictional resistance of thefirst balloon30 is smaller than that of thesecond balloon60. Thus, even if thefirst balloon30 and thesecond balloon60 move away from each other, since thefirst balloon30 with the smaller frictional resistance slides over theintestinal tract70, there is no fear that theintestinal tract70 is damaged by being pulled by thefirst balloon30 and thesecond balloon60.
• Next, as shown inFIG. 8H, thefirst balloon30 is deflated with air sucked from it. Then, thetip portion36 of theinsert portion12 is inserted as deeply as possible into theintestinal tract70. That is, the insertion operation shown inFIG. 8C is performed again. This allows thetip portion36 of theinsert portion12 to be inserted into the depth of theintestinal tract70. To insert theinsert portion12 further, the fixing operation shown inFIG. 8D, the pushing operation shown inFIG. 8E, the holding operation shown inFIG. 8F, the pull-in operation shown inFIG. 8G, and the insertion operation shown inFIG. 8H can be repeated in this order. This allows theinsert portion12 to be inserted more deeply into theintestinal tract70.
• During endoscopic procedures, lubricant is supplied to thetube body51 of theovertube50 from thelubricant supply portion72 inFIG. 1. The lubricant is poured through theinlet66, flows to thelubricant supply path68, and then is supplied to inside thetube body51 via a plurality ofopenings75 formed in thelubricant supply path68 andtube body51.
• Since the plurality ofopenings75 are formed at predetermined intervals from the base end portion to the tip portion of thetube body51, lubricant is supplied to the entire inner surface of thetube body51. Furthermore, since the opening areas of theopenings75 increase from the base end portion to the tip portion of thetube body51, the lubricant is supplied uniformly to the entire inner surface of thetube body51.
• Thus, theovertube50 according to this embodiment allows lubricant to be supplied uniformly to the entire inner surface of thetube body51 without increasing the diameter of thetube body51. This constantly provides good sliding characteristics, and thereby improves slidability of theinsert portion12 along thetube body51, reducing the time required for endoscopic procedures. Also, since good sliding characteristics are obtained constantly, it is possible to provide atube body50 of a small diameter by decreasing the inside and outside diameters of thetube body51 inserted into a body cavity and reducing the inside diameter of thetube body51 close to the diameter of theendoscope insert portion12.
• Also, as shown inFIG. 6, by installing a plurality oflubricant supply paths68 in thetube body51, it is possible to form a plurality ofopenings75 on the circumference of thetube body51, and thereby supply a more uniform amount of lubricant over the entire inner surface of thetube body51.
• Furthermore, as shown inFIGS. 7A and 7B, by installing alubricant supply path68 spirally on thetube body51, it is possible to form a plurality ofopenings75 on the circumference of thetube body51 using the singlelubricant supply path68, allowing lubricant to be supplied more uniformly to the entire inner surface of thetube body51 than when a single straightlubricant supply path68 is used.
• Incidentally, although anovertube50 with a balloon has been cited in this embodiment, the present invention is also applicable to a sliding tube which guides an endoscope insert portion into the body cavity without a balloon.
• FIG. 9 is a sectional view of an embodiment of anovertube50 where anopening75 is formed only near thetip58 of thetube body51 of theovertube50. The same or similar components as those of theovertube50 shown inFIG. 4 are denoted by the same reference numerals as the corresponding components inFIG. 4 and description thereof will be omitted.
• Alubricant supply path68 communicated with aninlet66 is laid on the outer surface of thetube body51 inFIG. 9 extending from the base end portion to thetip58 of thetube body51 and anopening75 which supplies the lubricant poured into thelubricant supply path68 to the inside of thetube body51 is formed near thetip58 of thetube body51 where thetip69 of thelubricant supply path68 is located.
• Between theendoscope insert portion12 and thetube body51, the part which particularly needs enhanced lubricity is thetip58 of theovertube50 where theinsert portion12 is rubbed by aninner edge59A of atip opening59 of thetube body51. As is the case with theovertube50 inFIG. 9, by forming theopening75 near thetip58 of thetube body51 where thetip69 of thelubricant supply path68 is located, thereby allowing the lubricant poured into thelubricant supply path68 to be supplied to the inside of thetube body51, i.e., to the clearance between inner surface of the applicator and outer surface of the endoscope insert portion, it is possible to supply the lubricant directly to thetip58 of thetube body51. Theovertube50 inFIG. 9 can improve the lubricity of thetip58 of theovertube50 which particularly needs enhanced lubricity.
• FIG. 10 is a system block diagram of an endoscope apparatus according to an embodiment the present invention. The endoscope apparatus shown in theFIG. 10 comprises anendoscope210, an overtube (corresponds to the applicator)250, and aballoon control apparatus300.
• Theendoscope210 is equipped with ahand controller214 and aninsert portion212 provided in a row arrangement with thehand controller214. Thehand controller214 is connected with auniversal cable215 whose tip is equipped with a connector (not shown) to be connected with a processor or light source (not shown).
• Thehand controller214 is equipped with an air/water feed button216,aspiration button218, and ashutter button220, which are provided in proximity in a row arrangement and operated by the physician. Also, it is equipped with a pair ofangle knobs222 and aforceps inlet224, which are placed at predetermined locations. Furthermore, thehand controller214 is equipped with a balloonair feed port226 to supply and suck air to/from afirst balloon230.
• Theinsert portion212 consists of asoft portion232, aflexible portion234, and arigid tip portion236. Theflexible portion234 is constructed from a plurality of joint rings connected flexibly. It is flexed remotely through rotation of the pair ofangle knobs222 mounted on thehand controller214. This makes it possible to orient atip surface237 of atip portion236 in a desired direction.
• As shown inFIG. 11, an objectiveoptical system238, anillumination lens240, an air/water supply nozzle242, aforceps port244, etc. are mounted at predetermined locations on thetip surface237 of thetip portion236. Also, an air supply/suction port228 opens to the outer surface of thetip portion236. The air supply/suction port228 is communicated with the balloonair feed port226 inFIG. 10 via an air supply tube (not shown) which is approximately 0.8 mm in inside diameter and which is passed through theinsert portion212. Consequently, when air is fed to the balloonair feed port226, the air supply/suction port228 in thetip portion236 emits air. When air is sucked through the balloonair feed port226, the air supply/suction port228 sucks air.
• As shown inFIG. 10, thefirst balloon230 made of an elastic body such as rubber is detachably attached to thetip portion236 of theinsert portion212. As shown inFIG. 12, thefirst balloon230 has aninflatable portion230cin the center and mountingportions230aand230bon both ends. It is attached to thetip portion236 in such a way that the air supply/suction port228 is located on the inner side of theinflatable portion230c. The mountingportions230aand230bhave smaller diameters than thetip portion236. They are brought into intimate contact with thetip portion236 by their own elastic force and then fitted over the outer surface of thetip portion236 securely with an annular band (not shown).
• Of thefirst balloon230 attached to thetip portion236, theinflatable portion230cis inflated into an approximately spherical shape by air supplied through the air supply/suction port228 shown inFIG. 11. When air is sucked through the air supply/suction port228, theinflatable portion230cis deflated and brought into intimate contact with the outer surface of thetip portion236.
• Theovertube250 shown inFIG. 10 has atube body251 and agrip portion252. As shown inFIG. 13, thetube body251 is tubular in shape and has an inside diameter slightly larger than the outside diameter of theinsert portion212. Also, thetube body251 is a molding of flexible urethane resin. Its inner and outer surfaces are covered with a lubricious coating. Thegrip portion252 is fitted watertight into thetube body251 to detachably connect thegrip portion252 to thetube body251. Incidentally, theinsert portion212 is inserted into thetube body251 through a base end opening252A of thegrip portion252.
• As shown inFIG. 10, a balloonair feed port254 is provided at the base end of thetube body251. The balloonair feed port254 is connected with anair supply tube256 approximately 1 mm in inside diameter. Being bonded to the outer surface of thetube body251, theair supply tube256 extends to the tip portion of thetube body251 as shown inFIG. 13.
• Atip portion258 of thetube body251 is tapered to prevent intestinal walls from being caught in or the like. Asecond balloon260 made of an elastic body such as rubber is attached to the base end of thetip portion258 of thetube body251 in such a way as to be penetrated by thetube body251. It has aninflatable portion260cin the center and mountingportions260aand260bon both ends. The mountingportion260aon the tip side is folded back into theinflatable portion260cand fastened to thetube body251, being wound by aradiopaque thread262. The mountingportion260bon the base end side is placed outside thesecond balloon260 and fastened to thetube body251, being wound by athread264.
• Theinflatable portion260chas an approximately spherical shape in normal state (when neither inflated nor deflated) and is larger than thefirst balloon230 in normal state (when neither inflated nor deflated). Thus, when air is fed to thefirst balloon230 andsecond balloon260 at the same pressure, theinflatable portion260cof the second balloon becomes larger in outside diameter than theinflatable portion230cof thefirst balloon230. For example, when the outside diameter of thefirst balloon230 is 25 mm, the outside diameter of thesecond balloon260 is 50 mm.
• Theair supply tube256 opens into theinflatable portion260cby forming an air supply/suction port257. Thus, when air is fed through the balloonair feed port254, it blows out of the air supply/suction port257 to inflate theinflatable portion260c. On the other hand, when air is sucked out of the balloonair feed port254, it is sucked through the air supply/suction port257, deflating thesecond balloon260.
• An engagingportion280 with multiple rows (three rows inFIG. 13) of serrations of a triangular cross section is formed as an antiskid member on the inner surface of thegrip portion252 of theovertube250. As shown inFIG. 14, the engagingportion280 is formed with a predetermined length in a direction orthogonal to the axial direction of thegrip portion252 and an engagingportion280 with multiple rows (three rows inFIG. 14) of serrations is similarly formed on the opposite face.
• Besides, an engagedportion282 with multiple rows (four rows inFIG. 14) of serrations of a triangular cross section is formed as an antiskid member at a predetermined location on the outer surface of theinsert portion212. The engagedportion282 is formed with a predetermined length in a direction orthogonal to the axial direction of theinsert portion212 and an engagedportion282 with multiple rows (four rows inFIG. 14) of serrations is similarly formed on the opposite face.
• The engagedportions282 are not engaged with the engagingportions280 of thegrip portion252 when thegrip portion252 is in normal state (when neither inflated nor deflated) as shown inFIG. 14. They are engaged, by being meshed, with the engagingportions280 of thegrip portion252 as shown inFIG. 13 when thegrip portion252 is squeezed in the direction indicated by arrows and deformed elastically in a diameter-reducing direction as shown inFIG. 15. That is, the diameter of thegrip portion252 and heights of the engaging and engagedportions280 and282 are designed such that thegrip portion252 does not engage the engagingportions280 and engagedportions282 with each other in the normal state shown inFIG. 14. Also, thegrip portion252 is made of a soft material so as to engage the engagedportions282 with the engagingportions280 when deformed elastically.
• Incidentally, the engagedportions282 may be provided either continuously along the length of theinsert portion212 or in groups of rows formed at predetermined intervals. From the viewpoint of preventing thetip portion258 from damaging theballoon230, preferably the engagedportions282 at the extreme tip of theinsert portion212 are formed in such a way that theballoon230 will not touch thetip portion258 of theovertube250 as shown in FIG.13 when the engagedportions282 are engaged with the engagingportions280.
• On the other hand, theballoon control apparatus300 inFIG. 10 supplies and sucks a fluid such as air to/from thefirst balloon230 as well as thesecond balloon260. Theballoon control apparatus300 includes anapparatus body302 equipped with a pump, sequencer, etc. (not shown) and a remotecontrol hand switch304.
• A power switch SW1, a stop switch SW2, apressure gauge306 for thefirst balloon230, and apressure gauge308 for thesecond balloon260 are installed on a front panel of theapparatus body302. Also, atube310 for use to supply and suck air to/from thefirst balloon230 and atube320 for use to supply and suck air to/from thesecond balloon260 are installed on the front panel of theapparatus body302. Thetubes310 and320 haveliquid reservoir tanks330 and340, respectively, to collect liquid flowing backward from thefirst balloon230 andsecond balloon260 in case thefirst balloon230 andsecond balloon260 burst, respectively.
• Thehand switch304 contains a stop switch SW3 similar to the stop switch SW2 of theapparatus body302, an ON/OFF switch SW4 for pressurization/depressurization of thefirst balloon230, a pause switch SW5 for use to maintain the pressure of thefirst balloon230, an ON/OFF switch SW6 for pressurization/depressurization of thesecond balloon260, and a pause switch SW7 for use to maintain the pressure of thesecond balloon260. Thehand switch304 is electrically connected to theapparatus body302 via acable350.
• Being configured as described above, theballoon control apparatus300 inflates thefirst balloon230 andsecond balloon260 by supplying air to them and keeps thefirst balloon230 andsecond balloon260 inflated by maintaining the air pressure at a fixed value. Also, theballoon control apparatus300 deflates thefirst balloon230 andsecond balloon260 by sucking air from them and keeps thefirst balloon230 andsecond balloon260 deflated by maintaining the air pressure at a fixed value.
• Next, an operation method of the endoscope apparatus will be described with reference toFIGS. 16A to 16H.
• First, as shown inFIG. 16A, theinsert portion212 is inserted in an intestinal tract (e.g., pars descendens duodeni)270 with theovertube250 put over theinsert portion212. At this time, thefirst balloon230 andsecond balloon260 are kept deflated.
• Next, as shown inFIG. 16B, with thetip258 of theovertube250 inserted to a bend of theintestinal tract270, thesecond balloon260 is inflated by air supplied to it. Consequently, thesecond balloon260 is restrained by theintestinal tract270 and thetip258 of theovertube250 is fixed to theintestinal tract270.
• Next, as shown inFIG. 16C, only theinsert portion212 of theendoscope210 is inserted into the depth of theintestinal tract270. Then, as shown inFIG. 16D, thefirst balloon230 is inflated by air supplied to it. Consequently, thefirst balloon230 is fixed to theintestinal tract270. Since thefirst balloon230 is smaller than thesecond balloon260 when inflated, there is less strain on theintestinal tract270. This prevents damage to theintestinal tract270.
• Next, after thesecond balloon260 is deflated with air sucked from it, theovertube250 is pushed in and inserted together with theinsert portion212 as shown inFIG. 16E. When thetip258 of theovertube250 is inserted to near thefirst balloon230, thesecond balloon260 is inflated with air supplied to it as shown inFIG. 16F. Consequently, thesecond balloon260 is fixed to theintestinal tract270. That is, theintestinal tract270 is held by thesecond balloon260.
• Then, as shown inFIG. 16G, theovertube250 is pulled in. This causes theintestinal tract270 to contract in a straightened state, eliminating excess bending and flexion of theovertube250.
• This operation involves pulling in theovertube250 andinsert portion212 simultaneously. Before performing this operation, the physician grips thegrip portion252 as shown inFIG. 13, squeezes thegrip portion252 in the direction indicated by arrows inFIG. 15, and thereby deforms it elastically in a diameter-reducing direction to engage the engagedportions282 of theinsert portion212 with the engagingportions280 of thegrip portion252. In this state, the physician pulls in theovertube250. Consequently, theinsert portion212 is pulled in together with theovertube250 via the engaging and engagedportions280 and282, which are antiskid members, without slipping along theovertube250.
• When theovertube250 is pulled in, thefirst balloon230 andsecond balloon260 are restrained by theintestinal tract270, and the frictional resistance of thefirst balloon230 is smaller than that of thesecond balloon260. Therefore, even if thefirst balloon230 andsecond balloon260 move away from each other, thefirst balloon230 with the smaller frictional resistance slides over theintestinal tract270. Thus, there is no fear that theintestinal tract270 is damaged by being pulled by thefirst balloon230 andsecond balloon260.
• Next, as shown inFIG. 16H, thefirst balloon230 is deflated with air sucked from it. Then, thetip portion236 of theinsert portion212 is inserted as deeply as possible into theintestinal tract270. That is, the insertion operation shown inFIG. 16C is performed again. This allows thetip portion236 of theinsert portion212 to be inserted into the depth of theintestinal tract270. To insert theinsert portion212 further, the fixing operation shown inFIG. 16D, the pushing operation shown inFIG. 16E, the holding operation shown inFIG. 16F, the pull-in operation shown inFIG. 16G, and the insertion operation shown inFIG. 16H can be repeated in this order. This allows theinsert portion212 to be inserted more deeply into theintestinal tract270.
• Incidentally, although according to this embodiment, antiskid members—the engagingportions280 or engagedportions282—are formed on both theovertube250 andinsert portion212, antiskid members may be formed on only one of them if they provide the frictional resistance required during pull-in operation.
• Also, although in this embodiment, theovertube250 with theballoon260 at the tip has been cited as an applicator, this is not restrictive and the antiskid members according to this embodiment may be provided on a sliding tube (an applicator without a balloon) used for a colonoscope.
• FIG. 17 shows a block diagram of an endoscope apparatus according to an embodiment of the present invention. The endoscope apparatus shown in theFIG. 17 comprises anendoscope410, anovertube450, and acontrol apparatus500.
• Theendoscope410 is equipped with ahand controller414 and aninsert portion412 provided in a row arrangement with thehand controller414. Thehand controller414 is connected with auniversal cable415 whose tip is equipped with a connector (not shown) to be connected with a processor or light source (not shown).
• Thehand controller414 is equipped with an air/water feed button416, anaspiration button418, and ashutter button420, which are provided in proximity in a row arrangement and operated by the physician. Also, thehand controller414 is equipped with a pair of angle knobs422,422 and aforceps inlet424, which are placed at predetermined locations. Furthermore, thehand controller414 is equipped with a balloonair feed port426 to supply and suck air to/from afirst balloon430.
• Theinsert portion412 consists of asoft portion432, aflexible portion434, and arigid tip portion436. Theflexible portion434 is constructed from a plurality of joint rings connected flexibly. It is flexed remotely through rotation of the pair ofangle knobs422 mounted on thehand controller414. This makes it possible to orient atip surface437 of arigid tip portion436 in a desired direction.
• As shown inFIG. 18, an objectiveoptical system438, anillumination lens440, an air/water supply nozzle442, aforceps port444, etc. are mounted at predetermined locations on thetip surface437 of therigid tip portion436. Also, an air supply/suction port428 opens to the outer surface of therigid tip portion436. The air supply/suction port428 is communicated with the balloonair feed port426 inFIG. 17 via an air supply tube (not shown) which is approximately 0.8 mm in inside diameter and which is passed through theinsert portion412. Consequently, when air is fed to the balloonair feed port426, the air supply/suction port428 in therigid tip portion436 emits air. When air is sucked through the balloonair feed port426, the air supply/suction port428 sucks air.
• As shown inFIG. 17, thefirst balloon430 made of an elastic body such as rubber is detachably attached to therigid tip portion436 of theinsert portion412. As shown inFIG. 19, thefirst balloon430 has aninflatable portion430cin the center and mountingportions430aand430bon both ends. It is attached to therigid tip portion436 in such a way that the air supply/suction port428 is located on the inner side of theinflatable portion430c. The mountingportions430aand430bhave smaller diameters than therigid tip portion436 and theflexible portion434. They are brought into intimate contact with therigid tip portion436 by their own elastic force and then fitted over the outer surface of therigid tip portion436 securely with an annular band member (not shown).
• Of thefirst balloon430 attached to therigid tip portion436, theinflatable portion430cis inflated into an approximately spherical shape by air supplied through the air supply/suction port428 shown inFIG. 18. When air is sucked through the air supply/suction port428, theinflatable portion430cis deflated and brought into intimate contact with the outer surface of therigid tip portion436.
• Theovertube450 shown inFIG. 17 has atube body451 and agrip portion452. As shown inFIG. 20, thetube body451 is tubular in shape and has an inside diameter slightly larger than the outside diameter of theinsert portion412. Also, thetube body451 is a molding of flexible urethane resin. Its inner and outer surfaces are covered with a lubricious coating. Thegrip portion452 is fitted watertight into thetube body451 to detachably connect thegrip portion452 to thetube body451. Incidentally, theinsert portion412 is inserted into thetube body451 through a base end opening452A of thegrip portion452.
• As shown inFIG. 17, a balloonair feed port454 is provided at the base end of thetube body451. The balloonair feed port454 is connected with anair supply tube456 approximately 1 mm in inside diameter. Being bonded to the outer surface of thetube body451, theair supply tube456 extends to the tip portion of thetube body451 as shown inFIG. 20.
• Atip portion458 of thetube body451 is tapered to prevent intestinal walls from being caught in or the like. Asecond balloon460 made of an elastic body such as rubber is attached to the base end of thetip portion458 of thetube body451 in such a way as to be penetrated by thetube body451. It has aninflatable portion460cin the center and mountingportions460aand60bon both ends. The mountingportion460aon the tip side is folded back into theinflatable portion460cand fastened to thetube body451, being wound by aradiopaque thread462. The mountingportion460bon the base end side is placed outside thesecond balloon460 and fastened to thetube body451, being wound by athread464.
• Theinflatable portion460chas an approximately spherical shape in normal state (when neither inflated nor deflated) and is larger than thefirst balloon430 in normal state (when neither inflated nor deflated). Thus, when air is fed to thefirst balloon430 andsecond balloon460 at the same pressure, theinflatable portion460cof thesecond balloon460 becomes larger in outside diameter than theinflatable portion430cof thefirst balloon430. For example, when the outside diameter of thefirst balloon430 is 25 mm, the outside diameter of thesecond balloon460 is 50 mm.
• Theair supply tube456 opens into theinflatable portion460cby forming an air supply/suction port457. Thus, when air is fed through the balloonair feed port454, it blows out of the air supply/suction port457 to inflate theinflatable portion460c. On the other hand, when air is sucked out of the balloonair feed port454, it is sucked through the air supply/suction port457, deflating thesecond balloon460.
• Incidentally, a strain gauge (pull-out force measuring device: e.g., Wheatstone bridge circuit)480 is installed at a predetermined location on theinsert portion412 as shown inFIG. 17 to measure the pull-out force of theinsert portion412. Similarly, a strain gauge (pull-out force measuring device: e.g., Wheatstone bridge circuit)482 is installed at a predetermined location on thetube body451 of theovertube450 to measure the pull-out force of thetube body451. The strain gauges480 and482 output electrical signals which represent minute strain in theinsert portion412 andtube body451.
• Thestrain gauge480 is connected to one end of asignal line484, which is laid from theinsert portion412 to thehand controller414 and extends to the outside from thehand controller414. The other end of thesignal line484 is connected to aconnector486 of thecontrol apparatus500. Thus, the electrical signals which come out of thestrain gauge480 and represent electrical resistance are outputted to thecontrol apparatus500 via thesignal line484.
• On the other hand, thestrain gauge482 is connected to one end of asignal line488, which is laid from thetube body451 to thegrip portion452 and extends to the outside from thegrip portion452. Thus, the electrical signals which come out of thestrain gauge482 and represent electrical resistance are outputted to thecontrol apparatus500 via thesignal line488.
• Thecontrol apparatus500 supplies and sucks a fluid such as air to/from thefirst balloon430 as well as thesecond balloon460. Also, it displays electrical resistance corresponding to the pull-out force of theinsert portion412 and pull-out force of thetube body451 on anLCD display492 based on the electrical signals outputted from the strain gauges480 and482.
• Thecontrol apparatus500 includes anapparatus body502 equipped with a pump, sequencer, etc. (not shown) and a remotecontrol hand switch504.
• A power switch SW1, a stop switch SW2, apressure gauge506 for thefirst balloon430, and apressure gauge508 for thesecond balloon460 are installed on a front panel of theapparatus body502. Also, atube510 for use to supply and suck air to/from thefirst balloon430 and atube520 for use to supply and suck air to/from thesecond balloon460 are installed on the front panel of theapparatus body502. Thetubes510 and520 haveliquid reservoir tanks530 and540, respectively, to collect liquid flowing backward from thefirst balloon430 andsecond balloon460 in case thefirst balloon430 andsecond balloon460 burst, respectively.
• Furthermore, theLCD display492, aresistance setting dial494, and awarning lamp496 are installed on the front panel of theapparatus body502. Theresistance setting dial494 is used to set a threshold of the electrical resistance specified on amicrocomputer498 shown inFIG. 21. That is, it sets thresholds of the pull-out forces (tensile forces) acting on theinsert portion412 and theovertube450. If a signal which represents a value exceeding the set electrical resistance (pull-out force) is outputted from thestrain gauge480 or482, themicrocomputer498 turns on thewarning lamp496.
• Also, themicrocomputer498 controls apump560 and pressurizing/pressure-reducing valve562 used to feed air to thefirst balloon430 based on command signals from thehand switch504. It switches a change-over valve (balloon pressure regulating device)564 based on the electrical signal outputted from thestrain gauge480. The change-overvalve564 has asupply gate564A andleak gate564B. If a electrical signal outputted from thestrain gauge480 exceeds the set threshold, the change-overvalve564 is switched from thesupply gate564A to theleak gate564B. Consequently, the air in thefirst balloon430 is released to the atmosphere through thetube510 and theleak gate564B, decreasing the internal pressure of thefirst balloon430.
• Furthermore, themicrocomputer498 controls apump570 and a pressurizing/pressure-reducing valve572 used to feed air to thesecond balloon460 based on command signals from thehand switch504. It switches a change-over valve (balloon pressure regulating device)574 based on the electrical signal outputted from thestrain gauge482. The change-over valve574 has asupply gate574A andleak gate574B. If a electrical signal outputted from thestrain gauge482 exceeds the set threshold, the change-over valve574 is switched from thesupply gate574A to theleak gate574B. Consequently, the air in thesecond balloon460 is released to the atmosphere through thetube520 and theleak gate574B, decreasing the internal pressure of thesecond balloon460.
• Thehand switch504 shown inFIG. 17 contains a stop switch SW3 similar to the stop switch SW2 of theapparatus body502, an ON/OFF switch SW4 for pressurization/depressurization of thefirst balloon430, a pause switch SW5 for use to maintain the pressure of thefirst balloon430, an ON/OFF switch SW6 for pressurization/depressurization of thesecond balloon460, and a pause switch SW7 for use to maintain the pressure of thesecond balloon460. Thehand switch504 is electrically connected to themicrocomputer498 on theapparatus body502 via acable550.
• Being configured as described above, thecontrol apparatus500 inflates thefirst balloon430 andsecond balloon460 by supplying air to them and keeps thefirst balloon430 andsecond balloon460 inflated by maintaining the air pressure at a fixed value. Also, it deflates thefirst balloon430 andsecond balloon460 by sucking air from them and keeps thefirst balloon430 andsecond balloon460 deflated by maintaining the air pressure at a fixed value.
• Next, an operation method of the endoscope apparatus will be described with reference toFIGS. 22A to 22H.
• First, as shown inFIG. 22A, theinsert portion412 is inserted in an intestinal tract (e.g., pars descendens duodeni)470 with theovertube450 put over theinsert portion412. At this time, thefirst balloon430 andsecond balloon460 are kept deflated.
• Next, as shown inFIG. 22B, with thetip458 of theovertube450 inserted to a bend of theintestinal tract470, thesecond balloon460 is inflated by air supplied to it. Consequently, thesecond balloon460 is restrained by theintestinal tract470 and thetip458 of theovertube450 is fixed to theintestinal tract470.
• Next, as shown inFIG. 22C, only theinsert portion412 of theendoscope410 is inserted into the depth of theintestinal tract470. Then, as shown inFIG. 22D, thefirst balloon430 is inflated by air supplied to it. Consequently, thefirst balloon430 is fixed to theintestinal tract470. Since thefirst balloon430 is smaller than thesecond balloon460 when inflated, there is less strain on theintestinal tract470. This prevents damage to theintestinal tract470.
• Next, after thesecond balloon460 is deflated with air sucked from it, theovertube450 is pushed in and inserted together with theinsert portion412 as shown inFIG. 22E. When thetip458 of theovertube450 is inserted to near thefirst balloon430, thesecond balloon460 is inflated with air supplied to it as shown inFIG. 22F. Consequently, thesecond balloon460 is fixed to theintestinal tract470. That is, theintestinal tract470 is held by thesecond balloon460.
• Then, as shown inFIG. 22G, theovertube450 is pulled in. This causes theintestinal tract470 to contract in a approximately straightened state, eliminating excess bending and flexion of theovertube450.
• Next, as shown inFIG. 22H, thefirst balloon430 is deflated with air sucked from it. Then, therigid tip portion436 of theinsert portion412 is inserted as deeply as possible into theintestinal tract470. That is, the insertion operation shown inFIG. 22C is performed again. This allows therigid tip portion436 of theinsert portion412 to be inserted into the depth of theintestinal tract470. To insert theinsert portion412 further, the fixing operation shown inFIG. 22D, the pushing operation shown inFIG. 22E, the holding operation shown inFIG. 22F, the pull-in operation shown inFIG. 22G, and the insertion operation shown inFIG. 22H can be repeated in this order. This allows theinsert portion412 to be inserted more deeply into theintestinal tract470.
• Incidentally, during the pull-in operation shown inFIG. 22G, since thefirst balloon430 andsecond balloon460 are inflated and placed in intimate contact with theintestinal tract470, the physician encounters pull-out resistance via theovertube450 andinsert portion412. The pull-out resistance corresponds to the electrical resistance value which is based on the electrical signal outputted from thestrain gauge480 installed on theinsert portion412 and the electrical resistance value which is based on the electrical signal outputted from thestrain gauge482 installed on thetube body451. These electrical resistance values are displayed on theLCD display492 of theballoon control apparatus100. This allows the physician to quantitatively grasp the pull-out force of theinsert portion412 and pull-out force of theovertube450 separately.
• Themicrocomputer498 of thecontrol apparatus500 contains preset values of electrical resistance corresponding to pull-out forces determined by giving a predetermined margin of safety to pull-out forces which are likely to adversely affect theintestinal tract470. Themicrocomputer498 calculates electrical resistance values based on electrical signals from the strain gauges480 and482, and turns on thewarning lamp496 if any calculated electrical resistance value exceeds the preset electrical resistance value. This allows the physician to know that the pull-out force exceeds its preset value and stop the pull-in operation temporarily. If only the electrical resistance value from thestrain gauge480 exceeds its preset value, the change-overvalve564 is switched from thesupply gate564A to theleak gate564B, reducing the internal pressure of thefirst balloon430. If only the electrical resistance value from thestrain gauge482 exceeds its preset value, the change-over valve574 is switched from thesupply gate574A to theleak gate574B, reducing the internal pressure of thesecond balloon460. Consequently the electrical resistance value is decreased sharply, and thus theintestinal tract470 is not affected adversely even if the physician continues the pull-in operation.
• Incidentally, the switching of the change-overvalves564 and574 are not essential. The physician who sees from the glow of thewarning lamp496 that the pull-out force exceeds its preset value may reduce the frictional resistance by turning theinsert portion412 orovertube450 in theintestinal tract470 before resuming the pull-in operation.
• Also, although theovertube450 with theballoon460 at the tip has been described in this embodiment, this is not restrictive. The pull-out force measuring device according to this embodiment may be installed on a sliding tube (an applicator without a balloon) used for a colonoscope and the pull-out force of the sliding tube may be determined quantitatively.
• Furthermore, although thestrain gauge482 has been cited as an example of the pull-out force measuring device in this embodiment, this is not restrictive. It is possible to construct theovertube450 orinsert portion412 from translucent rubber, transmit light through a portion which becomes thin when pulled, and measure the pull-out force quantitatively based on light transmittance. Alternatively, it is possible to connect a spring-based measuring device such as a spring scale to theovertube450 orinsert portion412, pull theovertube450 orinsert portion412 using the measuring device, and thereby measure the pull-out force.

Claims (8)

1. An endoscope apparatus, comprising:

an endoscope with a balloon attached to a tip portion of an insert portion; and

an applicator through which the insert portion of the endoscope is inserted into a body cavity,

wherein at least one of the insert portion and the applicator is equipped with a pull-out force measuring device which measures pull-out force of the insert portion or applicator.

2. The endoscope apparatus according toclaim 1, further comprising a balloon pressure adjusting device which reduces internal pressure of the balloon when the pull-out force measured by the pull-out force measuring device exceeds a predetermined value.

3. An endoscope apparatus, comprising:

an endoscope with a first balloon attached to a tip portion of an insert portion; and

an overtube whose tip is equipped with a second balloon and through which the insert portion of the endoscope is inserted into a body cavity,

wherein at least one of the insert portion and the overtube is equipped with a pull-out force measuring device which measures pull-out force of the insert portion or overtube.

4. The endoscope apparatus according toclaim 3, further comprising a balloon pressure adjusting device which reduces internal pressure of at least one of the first balloon and the second balloon when the pull-out force measured by the pull-out force measuring device exceeds a predetermined value.

5. The endoscope apparatus according toclaim 1, wherein the pull-out force measuring device is a strain gauge.

6. The endoscope apparatus according toclaim 2, wherein the pull-out force measuring device is a strain gauge.

7. The endoscope apparatus according toclaim 3, wherein the pull-out force measuring device is a strain gauge.

8. The endoscope apparatus according toclaim 4, wherein the pull-out force measuring device is a strain gauge.

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