US20050137613A1 - Operating trocar - Google Patents

Abstract

An operating trocar according to the invention includes a guide tube inserted through a body surface to introduce an endoscope and an operating instrument into a living body, and a flange portion provided on the guide tube to make a predetermined angle with a plane approximately perpendicular to an axial direction of the guide tube, the flange portion being fixed to an outer surface of the body surface. Preferably, the operating trocar also includes a gastightness retaining portion provided in the guide tube to retain gastightness between a circumferential surface of an internal hole of the guide tube and a medical instrument such as an endoscope and an operating instrument inserted in the internal hole of the guide tube.

Description

CROSS-REFERENCE TO RELATED APPLICATION
• This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2001-401943, filed Dec. 28, 2001, the entire contents of the application are incorporated herein by reference.
BACKGROUND OF THE INVENTION
• 1. Field of the Invention
• The present invention relates to a trocar for introducing an endoscope, a therapeutic instrument and the like into a living body during operation. A trocar according to the invention is suited to, for example, endoscopic surgical operation.
• 2. Description of the Related Art
• Various types of trocars for introducing endoscopes, therapeutic instruments and the like into living bodies are known.
• Japanese Utility Model Registration No. 3024069 discloses an art of providing a balloon-like stopper on a trocar to prevent the trocar from coming off.
• Japanese Patent Laid-Open No. 28666/1997 discloses an art of preventing a trocar from coming off, by expanding an expanding portion in a body cavity.
BRIEF SUMMARY OF THE INVENTION
• A trocar according to the invention includes a guide tube for introducing a medical instrument into a living body and a flange provided on an outer circumference of the guide tube at a location other than opposite ends thereof, the flange having a surface which comes into contact with an outer surface of the living body and which is oblique with respect to an axis of the guide tube.
• In addition, it is preferable that at least a part of the trocar be formed of an elastic material so that the trocar can follow the movement of the medical instrument.
• In the trocar, it is general to integrate the guide tube and the flange, but the guide tube and the flange may also be constructed to be removably secured to each other so that the trocar can be conveniently cleaned and stored. In addition, this construction makes it easy to manufacture trocars.
• In addition, in order to increase the adhesion between the flange and the outer surface of the living body, it is preferable to provide a fixing portion (for example, an adhesive layer provided on the surface of the flange which comes into contact with the outer surface of the living body, an adhesive sheet wider in area than the flange and stuck to the surface of the flange opposite to the surface which comes into contact with the outer surface of the living body, or a fixing band extending from the flange). Holes through which to pass sutures may also be provided in the flange in order to fix the trocar to the living body.
• In the guide tube, a gastightness retaining member (for example, an O-ring or a valve) may also be provided so that the gastightness of a body cavity can be efficiently retained.
• It is preferable that the wall thickness of the guide tube be made a thickness suited for the insertion of the guide tube and the wall thickness of the flange be made a thickness which enables the flange to easily adhere to the body surface. Accordingly, in general, both wall thicknesses differ from each other, and in many cases, the flange is thinner in wall thickness than the guide tube.
• Some of the above-described additional features of the invention can also be applied to known trocars.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
• These and other features, aspects, and advantages of the apparatus and methods of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where:
• FIG. 1 is an exploded side view of a blood vessel harvester including a trocar according to a first embodiment of the invention;
• FIG. 2A is a perspective view of the trocar according to the first embodiment, andFIG. 2B is a longitudinal sectional view of the same trocar;
• FIG. 3 is a view showing the state in which a dissected portion of skin is formed in a lower limb according to the first embodiment;
• FIG. 4 is a cross-sectional view showing the state in which the trocar according to the first embodiment is fitted into the dissection portion of skin of the lower limb and a dissector is inserted into a cavity by using the trocar as a guide;
• FIG. 5 is a general construction diagram showing the state in which a therapeutic sheath is inserted into the cavity by using the trocar in the first embodiment as a guideFIG. 6 is a perspective view of a trocar according to a second embodiment of the invention;
• FIG. 7 is a cross-sectional view showing the manner in which the trocar shown inFIG. 6 is used
• FIG. 8 is a perspective view of a trocar according to a third embodiment of the invention
• FIG. 9 is a cross-sectional view showing the manner in which the trocar shown inFIG. 8 is used;
• FIG. 10 is a perspective view of a trocar according to a fourth embodiment of the invention
• FIG. 11 is a cross-sectional view showing the manner in which the trocar shown inFIG. 10 is used
• FIG. 12 is a perspective view of a trocar according to a fifth embodiment of the invention;
• FIG. 13 is a cross-sectional view showing the manner in which the trocar shown inFIG. 12 is used;
• FIG. 14 is a perspective view of a trocar according to a sixth embodiment of the invention
• FIGS. 15A to15C are perspective views showing a plurality of trocars which differ in the inclination angles of their guide tubes to their flanges;
• FIG. 16 is a perspective view showing the manner in which the trocars shown inFIGS. 15A to15C are used;
• FIG. 17 is a perspective view showing the manner in which the trocars shown inFIGS. 15A to15C are used; and
• FIG. 18A is a perspective view of a trocar according to a seventh embodiment of the invention, andFIG. 18B is a cross-sectional view of the trocar shown inFIG. 18A.
DETAILED DESCRIPTION OF THE INVENTION
• Preferred embodiments of the invention will be described below with reference to the accompanying drawings.
• FIG. 1 shows an endoscopic blood vessel harvester including a trocar for endoscopic operation according to a first embodiment of the invention. As shown, the endoscopic blood vessel harvester is made of atrocar1, atherapeutic sheath2, adissector3 which serves as expanding means, and a rigid scope4 which serves as an endoscope.
• As shown inFIGS. 2A and 2B, thetrocar1 comprises aflange5 which has an approximately disk-like shape and is provided with acylindrical guide tube6 in such a manner that theguide tube6 is obliquely inserted through theflange5. In many cases, trocars are integrally molded from a synthetic resin material (for example, polysulfone), or formed of a metal (for example, SUS 304 stainless steel). In the first embodiment, thetrocar1 is formed of an elastic material (for example, silicone rubber) so that thetrocar1 has elasticity. As a matter of course, when thetrocar1 is to be given elasticity, the whole of thetrocar1 need not be formed of an elastic material, and only the necessary part of thetrocar1 may be formed of an elastic material. In many cases, the portions of guide tubes that are to be inserted into the bodies of patients do not need great elasticity, but flange portions which come into contact with the body surfaces of patients need great elasticity. In view of this situation, an elastic material can also be used mainly for the flange portions.
• The outer surface of theguide tube6 is covered with a lubricating coating for improving the smoothness of insertion of theguide tube6. Atip6aof thisguide tube6 is cut at an acute angle, and the end surface of thetip6ais formed approximately in parallel with theflange5.
• In addition, the inner circumferential surface of the proximal end of theguide tube6 is integrally provided with agastight ring portion7 which serves as a gastightness retaining member (a sealing member), and an intermediate portion of theguide tube6 is integrally provided with a gasfeed connecting portion8. The gastightness retaining member is provided on a side closer to the proximal end than the gas feed connecting portion8 (on a side far from the interior of a patient). This construction aims to prevent a gas fed into thetrocar1 through the gasfeed connecting portion8 from leaking out of thetrocar1 at the proximal end. In addition, the bottom or contact surface of the flange5a(the surface of theflange5 which comes into contact with the patient) is provided with an adhesive layer9 (for example, adhesive tape) so that thetrocar1 can be adhesively fixed to the skin of the patient.
• As shown inFIG. 1, thetherapeutic sheath2 has asheath body10. Thesheath body10 has the form of a straight cylinder made of a synthetic resin material or the like, and the outer surface of thesheath body10 is covered with a lubricating coating for improving the smoothness of insertion of thesheath body10. Thesheath body10 is constructed so that a rigid scope4 can be freely inserted into and extracted from the interior of thesheath body10. In addition, thesheath body10 is provided with a first therapeutic instrument channel and a second therapeutic instrument channel. Abipolar cutter18 is inserted through the first therapeutic instrument channel as a high-frequency therapeutic instrument. Thebipolar cutter18 is constructed to move axially back and forth when a therapeuticinstrument manipulating portion19 is slid axially back and forth. In addition, ablood vessel holder21 is inserted through the second therapeutic instrument channel, and is constructed to move axially back and forth when aholder manipulating portion22 is slid axially back and forth.
• Thedissector3 has a straightcylindrical inserting tube36, as shown inFIG. 1. An axial portion of this insertingtube36 is provided with an inserting passage through which to insert an insertingportion35 of the rigid scope4. The outer surface of the insertingtube36 is covered with a lubricating coating for improving the smoothness of insertion of the insertingtube36. A dissectingportion38 made of a transparent synthetic resin material formed into a conical shape is fixed to the distal end of the insertingtube36.
• The rigid scope4 has the insertingportion35 and aneyepiece portion31, and a lightguide connecting portion33 is provided on the side of the rigid scope4.
• A case where the blood vessel harvester constructed in the above-described manner is used to extract an extraction target blood vessel (hereinafter referred to simply as a blood vessel) along the full length thereof will be described below with illustrative reference to a great saphenous vein which extends from the inguinal region of the thigh to the ankle of either of the lower limbs.
• FIG. 3 shows alower limb60, andreference numeral61 denotes a blood vessel. A dissected portion ofskin64 is provided between aknee62 and aninguinal region63. As shown, when an operator is to extract theblood vessel61 between theknee62 and theinguinal region63, the operator provides the dissected portion ofskin64 at one location of theknee62 immediately above theblood vessel61 by means of a scalpel or the like.
• Then, the operator exposes theblood vessel61 in the dissected portion ofskin64 by means of thedissector3 or the like. Further, the operator dissects tissues immediately above theblood vessel61 by means of thesimilar dissector3 or the like over a distance from the dissected portion ofskin64, which distance is observable with the naked eyes.
• FIG. 5 shows the manner in which thetherapeutic sheath2 having the rigid scope4 inserted inside is inserted through thetrocar1. In the combination shown inFIG. 5, thedissector3 may also be substituted for thetherapeutic sheath2. In this substituted combination, the operator proceeds dissection with thedissector3. An image of the status of dissection through the dissectingportion38 of thedissector3 is picked up by aTV camera75 via aTV camera head74 connected to theeyepiece portion31 of the rigid scope4, and the picked-up image is displayed on amonitor76 as a monitor image.
• Then, as shown inFIG. 4, the operator inserts the dissectingportion38 along theblood vessel61, and when the dissectingportion38 is inserted to a small extent, the operator inserts theguide tube6 of thetrocar1 toward theinguinal region63 obliquely (approximately in parallel with the blood vessel61). When thetip6aof thetrocar1 is turned downward, theadhesive layer9 on the bottom surface5aof theflange5 is adhesively fixed toskin65. In this state, the operator connects agas feed tube67 connected to agas feed pump66 to the gasfeed connecting portion8.
• In this case, since the outer circumferential surface6fthe insertingtube36 of thedissector3 adheres closely to thegastight ring portion7, the interior of theguide tube6 and the interior of acavity69 is placed in a gastight state, and agas feed passage68 is established in an annular space between an inner surface of theguide tube6 and the outer circumferential surface of the insertingtube36.
• The lightguide connecting portion33 of the rigid scope4 is connected to alight source device78 via alight guide cable57. Accordingly, illuminating light can be projected from a tip portion of the rigid scope4 to illuminate the interior of thecavity69. When thegas feed pump66 is driven, a gas is fed into thecavity69 via thegas feed tube67, the gasfeed connecting portion8 and thegas feed passage68, whereby thecavity69 is expanded.
• At this time, in thecavity69, asubcutaneous tissue70 and a connective tissue ofblood vessel71 lie under theskin65, and ablood vessel61 exists under the connective tissue ofblood vessel71. Theblood vessel61 has a plurality ofside branches72, and the branch ends of therespective side branches72 are connected to the connective tissue ofblood vessel71.Subcutaneous fat73 adheres to the connective tissue ofblood vessel71.
• Subsequently, the operator inserts the dissect or 3 more deeply in the expandedcavity69 while guiding thedissector3 by means of theguide tube6. At this time, since theguide tube6 is formed to extend obliquely with respect to theflange5, theguide tube6 can guide thedissector3 obliquely with respect to the body surface, thereby successfully introducing thedissector3 along the running direction of theblood vessel61.
• During the insertion of thedissector3, while the operator is observing thecavity69 on themonitor76 to take care not to injure theblood vessel61 nor theside branches72, the operator gradually advances thedissector3 by repeating the manipulation of pushing thedissector3 to a small extent to dissect the connective tissue ofblood vessel71 from theblood vessel61 and theside branches72 by means of the dissectingportion38 and then pull ng thedissector3 to a small extent. During this time, even if thedissector3 is oscillated vertically and horizontally, thetrocar1 does not at all come off theskin65, because thetrocar1 is fixed to theskin65 by theadhesive layer9. In addition, since the trocar1 (theguide tube6 and the flange5) is formed of an elastic material, thetrocar1 can smoothly follow the movement of thedissector3 owing to its elastic deformation (thetrocar1 can absorb the deformation of the body surface due to the movement of the dissector3).
• After the operator has inserted thedissector3 along theblood vessel61 from theknee62 toward theinguinal region63 and completed a dissecting operation with thedissector3 in the above-described manner, the operator extracts thedissector3 from thetrocar1. Then, as shown inFIG. 5, the operator inserts thetherapeutic sheath2 in which the rigid scope4 is inserted, into theguide tube6 of thetrocar1. At this time as well, theguide tube6 which is formed to extend obliquely with respect to theflange5 can guide thetherapeutic sheath2 obliquely with respect to the body surface, thereby successfully introducing thetherapeutic sheath2 along the running direction of theblood vessel61.
• When the operator grips thetherapeutic sheath2 in one hand and advances theholder manipulating portion22 by using, for example, the thumb of the one hand, theblood vessel holder21 projects from the tip of thesheath body10. In addition, when the operator advances the therapeuticinstrument manipulating portion19 by using the index finger of the one hand in which thetherapeutic sheath2 is gripped, thebipolar cutter18 projects from the tip of thesheath body10. Namely, the operator can move theblood vessel holder21 and thebipolar cutter18 back and forth while gripping thesheath body10 in only one hand. Accordingly, the operator can easily sever theside branches72 by means of thebipolar cutter18 while holding theblood vessel61 to be extracted, by means of theblood vessel holder21. At this time as well, the trocar1 (theguide tube6 and the flange5) which is formed of an elastic material can smoothly follow the movement of thetherapeutic sheath2 owing to its elastic deformation.
• The operator repeats the operation of severing each of theside branches72 to dissect theblood vessel61 from the connective tissue ofblood vessel71, and when the operation advances up to theinguinal region63, the operator completes severing theside branches72. Then, the operator forms a small dissected portion of skin in theinguinal region63 immediately above theblood vessel61 by means of a scalpel or the like, and draws out theblood vessel61 through this dissected portion ofskin64. The operator can sever the drawn portion of theblood vessel61, and ligates both severed ends of theblood vessel61 with a suture. Then, the operator performs the operation of extracting the portion of theblood vessel61 that extends from the dissected portion ofskin64 of theknee62 toward the ankle of thelower limb60, thereby finally extracting a single blood vessel (about 60 cm long). The method of manipulation is basically the same as the above-described method of harvesting the portion of theblood vessel61 that extends from theknee62 to theinguinal region63, and detailed explanation is omitted. The vessel which is cut its both sides is removed from the dissected portion ofskin64.
• As described above, thetrocar1 according to the first embodiment is provided with theflange5 which is to be adhesively fixed to the body surface. Accordingly, thetrocar1 does not need to have a complicated stopper structure such as a balloon or an expanding portion, and makes it possible to prevent theguide tube6 from coming off, merely by adhesively fixing theflange5 to the body surface. Namely, thetrocar1 according to the first embodiment is inexpensive in that theguide tube6 can be effectively prevented from coming off, by means of a simple construction.
• In addition, in thetrocar1 according to the first embodiment, theflange5 is provided on theguide tube6 so as to make a predetermined angle (except zero degrees) with a plane approximately perpendicular to the axial direction of theguide tube6. In other words, theguide tube6 extends through theflange5 obliquely with respect to the extending direction of theflange5. Accordingly, theguide tube6 can guide an endoscope, a therapeutic instrument and the like obliquely with respect to the body surface. Therefore, the operator can make observations in various directions through an endoscope inserted through theguide tube6, and can also guide an endoscope and a therapeutic instrument in various directions as occasion demands. Particularly in the case of the first embodiment used for the extraction of a blood vessel, thedissector3 can be guided obliquely with respect to the body surface, thereby successfully introducing thedissector3 along the running direction of theblood vessel61.
• In addition, since theflange5 is provided on the outer circumference of theguide tube6 at a location other than the opposite ends thereof, a part of theguide tube6 is exposed outside the body of the patient when thetrocar1 is inserted in the patient. Accordingly, the operator can easily grip thetrocar1 with good operability.
• Thetrocar1 according to the first embodiment is provided with, in addition to the stopper structure (the flange5), the gastightness retaining member (sealing member)7 which retains the gastightness of the gap between the circumferential surface of the internal hole of theguide tube6 and an outer surface of an endoscope or a therapeutic instrument inserted in the internal hole (or conduit) of theguide tube6. Accordingly, thetrocar1 can reliably retain the gastightness of a body cavity, this feature is particularly important for endoscopic surgical operation.
• In addition, since thetrocar1 according to the first embodiment is formed of an elastic material, the whole of thetrocar1 can smoothly follow the movement of the dissect or3 owing to its elastic deformation (thetrocar1 can absorb the deformation of the body surface due to the movement of the dissector3).
• Furthermore, since thetrocar1 is formed of an elastic material, the angle made by theflange5 with the axis of theguide tube6 is variable within an elastically allowable range. Accordingly, when thetrocar1 is inserted in the patient, theflange5 can easily adhere to the body surface of the patient. As a matter of course, the angle made by theflange5 with the axis of theguide tube6 can also be made variable by using a mechanical joint (for example, theguide tube6 is inserted through a spherical member and a flange having a center opening which diameter is smaller than the diameter of the spherical member and larger than the diameter of theguide tube6 is fitted onto theguide tube6 as the flange5).
• Incidentally, in the first embodiment, the whole of thetrocar1 is formed of an elastic material, but at least one of theflange5 and theguide tube6 or at least a part of theflange5 or at least a part of theguide tube6 may be formed of an elastic material. Means for fixing the flange to the body surface is not limited to adhesion, and any fixing means that can easily fix theflange5 to the body surface may be used. In addition, the gastightness retaining member (sealing member)7 need not be an O-ring such as that used in the first embodiment, and may have any construction that can retain the gastightness of the body cavity.
• FIGS.6 to18 show other embodiments of the invention (a second embodiment to a seventh embodiment). In these embodiments, constituent portions common to the first embodiment are denoted by the same reference numerals as those used in the first embodiment, and the description of the same constituent portions is omitted.
• FIGS. 6 and 7 show atrocar1A according to the second embodiment of the invention. Thetrocar1A according to the second embodiment does not have theadhesive layer9 provided on the bottom surface5aof theflange5. Instead, anadhesive seal100 having an adhesive layer10ais stuck to theflange5, and as shown inFIG. 7, theflange5 is fixed to the body surfaces65 and70 by using theadhesive seal100. Incidentally, the constructions of the other portions are the same as those in the first embodiment.
• According to the construction of the second embodiment, since theadhesive layer9 is not provided, it is possible to produce thetrocar1A itself more easily, and as long as theadhesive seal100 has elasticity, thetrocar1A can follow the movement of an endoscope and a therapeutic instrument to some extent even if neither theflange5 nor theguide tube6 has elasticity. For example, theseal100 is a polyurethane film on one side of which hypoallergenic acrylic adhesive is applied. In this case, theseal100 has elasticity since polyurethane is used as a base material.
• FIGS. 8 and 9 show atrocar1B according to the third embodiment of the invention. As shown inFIG. 8, thetrocar1B according to the third embodiment is constructed so that theflange5 and theguide tube6 can be separated from each other. Specifically, a fixedring105 is provided on the inner circumference of the ring-shapedflange5, and an engaginggroove6bwhich engages with the fixedring105 is formed on the outer circumferential surface of theguide tube6. The engaginggroove6bobliquely extends to make a predetermined angle with a plane perpendicular to the direction of the longitudinal axis of theguide tube6, and the engaginggroove6bis arranged to direct theguide tube6 obliquely with respect to the extending direction of theflange5 when the engaginggroove6bengages with the fixed ring105 (theflange5 is arranged to be directed by the engaginggroove6bso that theflange5 makes a predetermined angle with a plane approximately perpendicular to the axial direction of the guide tube6). In addition, since the engagement is so tight, a seal capable of fully retaining the gastightness of a body cavity is formed when the engaginggroove6band the fixedring105 are engaged with each other. Incidentally, the constructions of the other portions are the same as those in the first embodiment. Theflange5 and fixedring105 are elastomers or a soft thermoplastic which can be plastically deformed to stretch over the guide tube. When theflange5 is fixed to theguide tube6, theflange5 and fixedring105 are extended until the fixedring105 corresponds with thegroove6b, at which point, the flange is relaxed and the fixedring105 engages with thegroove6b.
• FIG. 9 shows the state in which theguide tube6 which is fitted in theflange5 is fixed to the body surface s65 and70. As shown, theguide tube6 extends obliquely with respect to the body surfaces65 and70, whereby the third embodiment can serve effects and advantages similar to those of the first embodiment.
• According to the third embodiment, since theguide tube6 and theflange5 can be separated in the above-described manner, thetrocar1B is superior in ease of cleaning and ease of storage, and is also easy to manufacture. In addition, thetrocar1B is useful in that theflange5 and theguide tube6 can be formed of different materials. In addition, the engaging portion of theguide tube6 may use spaced projections (not shown) instead of the engaginggroove6bwhere the fixedring105 is captured between the spaced projections.
• FIGS. 10 and 11 show atrocar1C according to the fourth embodiment of the invention. As shown inFIG. 10, thetrocar1C according to the fourth embodiment does not have theadhesive layer9 provided on the bottom surface of theflange5. Instead, a plurality ofholes110 for tying sutures are formed in theflange5. Incidentally, the constructions of the other portions are the same as those in the first embodiment.
• According to the construction of the fourth embodiment, as shown inFIG. 11 by way of example, after a needle (not shown) with asuture112 has been stuck into the body surface s65 and70, the needle is passed through one of theholes110 of theflange5 and both ends of thesuture112 are tied together, whereby theflange5 can be fixed to the body surfaces65 and70 by thesutures112.
• FIGS. 12 and 13 show atrocar1D according to the fifth embodiment of the invention. As shown inFIG. 12, thetrocar1D according to the fifth embodiment has a construction in which aband129 extending from theflange5 has a Hook-and-Loop fastener (for example, Velcro® fastener)121 whose fastening halves are respectively provided at the opposite ends of theband129. Namely, theflange5 and theband129 form a fixingbelt120 for fixing theguide tube6 to a living body. Incidentally, the constructions of the other portions are the same as those in the first embodiment. Theband129 is made of elastomer or soft thermoplastic, and is attached to theguide tube6 likeflange5 in the third embodiment.
• According to the construction of the fifth embodiment, as shown inFIG. 13, it is possible to prevent theguide tube6 from coming off, by winding the fixingbelt120 around, for example, theknee62 of thelower limb60.
• Accordingly, since thetrocar1D according to the fifth embodiment has belt-like stopper means, thetrocar1D can be reliably fixed, and is particularly suited to an arm, a leg and the like.
• FIG. 14 shows atrocar1E according to the sixth embodiment. In thetrocar1E according to the sixth embodiment, the gastightness retaining member (sealing member) provided in theguide tube6 is formed as avalve7A. Specifically, atubular support portion125 which supports a valve flap151 in a turnable manner extends to project into theguide tube6 from the operator side of theguide tube6, and a member (for example, an elastic body)150 which comes into pressure contact with the outer circumferential surface of an endoscope or a therapeutic instrument to be inserted into theguide tube6 is fitted to the external end of thesupport portion125. Incidentally, the valve flap151 can open and close the passage of theguide tube6 by turning about apivot127 provided in thesupport portion125. In addition, the valve flap151 is biased in the closing direction by aspring152. The constructions of the other portions are the same as those in the first embodiment.
• According to the construction of the sixth embodiment, when an endoscope or a therapeutic instrument is inserted into thesupport portion125 to press the valve flap151, the valve flap151 is turned and opened against the urging force of thespring152, whereby the endoscope or the therapeutic instrument can be inserted through theguide tube6. In this case, since theelastic body150 comes into pressure contact with the outer circumferential surface of the endoscope or the therapeutic instrument, the gastightness of the body cavity can be retained. In addition, even after the endoscope or the therapeutic instrument has been removed from theguide tube6, the gastightness of the body cavity can still be retained, because the valve flap151 is closed by the biasing force of thespring152.
• FIGS. 15A to15C respectively show a plurality oftrocars1F,1G and1H which differ in the inclination angle of theguide tube6 to theflange5. Thesetrocars1F,1G and1H are used for introducing a plurality ofoperating instruments130,2, and132, respectively, into the body of a patient, and the operatinginstruments130,2, and132 differ in access direction relative to a therapeutic target part (affected part) O (hence, in inclination angle relative to the body surface) as shown inFIG. 16. The therapeutic target part O to be accessed may be an organ inside anabdominal wall140 as shown inFIG. 17, or may also be theblood vessel61 inside thelower limb60 as described previously. Accordingly, the kind of area to which the trocar according to the invention can be applied is not at all be limited.
• FIGS. 18A and 18B show a trocar1I according to the seventh embodiment of the invention. As clearly shown inFIG. 18A, in the trocar1I according to the seventh embodiment, a wall thickness t2 of theflange5 is set to be thinner than a wall thickness t1 of theguide tube6. Incidentally, the constructions of the other portions are the same as those in the first embodiment.
• Incidentally, in the case where the wall thickness of theflange5 is not constant or the wall thickness of theguide tube6 is not constant, the wall thickness of theguide tube6 may be determined from the average wall thickness of the portion of theguide tube6 that is to be inserted into a living body, while the wall thickness of theflange5 may be determined from the average wall thickness of the portion of theflange5 that is to come into contact with a living body.
• According to the construction of the seventh embodiment, theguide tube6 can be easily inserted into a dissected portion of skin, and theflange5 can be easily made to adhere to the skin.
• While there has been shown and described what is considered to be preferred embodiments of the invention, it will, of course, be understood that various modifications and changes in form or detail could readily be made without departing from the spirit of the invention. It is therefore intended that the invention be not limited to the exact forms described and illustrated, but should be constructed to cover all modifications that may fall within the scope of the appended claims.

Claims (3)

1-37. (canceled)

38. A method of inserting a trocar into a living body, comprising the steps of:

inserting at least a portion of the trocar into the living body;

causing at least a portion of a flange of the trocar and an outer surface of the living body to adhere to each other; and

adhering an adhesive sheet having at least a portion wider in area than the flange to the flange as well as the outer surface of the living body to fix the trocar to the living body.

39. A method of inserting a trocar into a living body, comprising the steps of:

inserting at least a portion of the trocar into the living body; and

fixing the trocar to the living body by securing a band extending from the trocar around a portion of the living body.

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