JPH04506912A - vascular catheter - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Background of the Invention of an Improved Guidewire Device for Intravascular Catheters 1. Field of invention The present invention relates generally to the construction and use of vascular catheters. Further, in detail, the present invention Both movable and fixed guidewires are used for positioning within the vascular system. The invention relates to intravascular catheters and catheter devices for use.

Arteriosclerosis, also known as atherosclerosis, is the formation of atheromas or small blood vessels on the walls of blood vessels. It is a common human disease caused by the deposition of fatty substances referred to as plaque. Kaka Deposits occur in the peripheral blood vessels that nourish the body's limbs and in the coronary blood vessels that nourish the heart. . When deposits build up in localized areas of blood vessels, blood flow is restricted and a person's health is compromised. fall into a serious crisis.

Balloon-tipped catheters to reduce and remove such vascular deposits Balloon angioplasty, blades or others used to dilate areas of atheroma atherectomy, which uses cutting elements to cut and remove atheroma, and Laser angioplasty that uses laser energy to ablate at least a portion of an atheroma A number of approaches have been proposed, including In addition to such therapeutic attempts, endos Atheroma and other vascular disease areas, including Coop imaging and ultrasound imaging Various techniques have been proposed for transluminal imaging.

All such techniques involve moving a vascular catheter to the desired site within the blood vessel to be treated or imaged. need to be positioned. Conventionally, two types of attempts have been adopted for such positioning. . In a first attempt, a vascular catheter was fitted with a "fixed guide wire" fixed to the distal end. It has "Ya". The fixed guide wire above is coil spring or preformed. It is an elongated flexible member with a curved tip. The above catheters are all catheters. is guided from the branch to the vascular network by rotating the The tip of the ear is advanced into the desired branch while advancing the catheter.

In the second method, a completely separate "movable guide wire" is used. The above movable The guidewire itself may be a coil spring or other flexible elongated member. , having a curved tip similar to that provided on the fixed guidewire described above. position The determined vascular catheter has a wire sized to receive the movable guide wire. It has holes. The movable guidewire first has a distal end thereof extending from the region of interest. positioned within the vascular system so as to Then, insert the vascular catheter into the guide. A guide wire is used to insert it onto the movable guide wire.

The above procedure using a movable guidewire is usually referred to as an “over-the-wire” insertion method. It will be done.

Each attempt at catheter insertion has a number of advantages and disadvantages. Fixed guide wire device The device requires fewer insertion steps and does not interfere with the diagnostic and/or therapeutic procedure being performed. There is no separation guidewire, and the guidewire is used after the catheter procedure step. The advantage is that it is in a position that allows for repositioning.

The movable guidewire described above is difficult to manipulate using a fixed guidewire. This is advantageous in that it facilitates the positioning of large diameter catheters.

The disadvantages of various guidewire devices largely outweigh the advantages described above.

The fixed guidewire systems described above are difficult to manipulate and generally not suitable for large diameter catheters. , on the other hand, the movable guide wire device described above is capable of following the catheter during a diagnostic or therapeutic procedure. Must be maintained in place to allow repositioning. The above movable guide wire The presence of fill a limited space.

Therefore, it has the advantages of combining the fixed guidewire and the movable guidewire device. The present invention provides a flexible catheter structure and method of insertion without attendant disadvantages. is desirable. In particular, if a movable guide wire is used first to determine the °C position, then It would be desirable to provide a catheter that can be positioned even after removal of the movable guidewire. Delicious.

2. Description of conventional technology US Patent No. 4,669.469 and European Patent Application No. 163,502 Each includes a distal housing having an axially movable blade. This article describes a cystectomy catheter consisting of a tube. This catheter It has a fixed guidewire or a movable guidewire, but not both. U.S. special No. 4,794.931 describes an ultrasound imaging catheter and Tel uses a fixed guidewire for positioning. US Patent No. 4.59 No. 7.755 has a large diameter balloon growing a coil spring within its distal end. It describes the catheter. This coil spring prevents twisting of the catheter. The purpose is to prevent catheter positioning and not to position the catheter. US Patent No. No. 4,571.240 discloses a bar with radiographic markers at the distal end of the catheter body. Describes the Rune catheter. The distal tip of this catheter is elongated but fixed. Not suitable for acting as a guidewire. US Patent No. 4.582.181 covers all For balloon catheters with an integral guidewire extending the length of the catheter. Describe it. The guidewire is a helical coil attached to the distal end of the catheter. terminates with an virus. The movable guidewire is described in US Pat. No. 4,724,846, no. , 682,607 and 4,215,703. These patents The contents of this document are referenced here. US Patent No. 4,586.923 is curved a catheter with a tip tip that is equipped with a mechanism for selectively deflecting the tip tip; Ru. US Pat. No. 4,596,563 describes A catheter that develops a flexible tip is described. US Patent No. 4,636,346 Describes a guide catheter intended to facilitate the introduction of lumen catheters . US Patent Nos. 4,775.371, 4,677°436 and 4,62 See No. 7.436.

Summary of the invention In accordance with the present invention, a vascular catheter has the ability to receive a movable guidewire as well as a fixed guidewire. equipped with an id wire. In this way, the vascular catheter is initially ・Using “wire” technology, the position can be adjusted and the diameter of the cable can be adjusted to a very large 7°. Even operations become easier. After initially positioning the catheter Remove the guide wire7. . Subsequently, the fixed guide wall that remains in the record is 1. In this way (=shi), the present invention uses a fixed guide wire and ■Assemble the moving guide 1st wire in advance.

Each catheter configuration has its own benefits.Furthermore, the method of As a result, the above-mentioned Wir, RT, example mail, perfusion map! Ha:ygH-2 1. Other purposes during Kabutol treatment (1, 50-m excision device available) ``Please put it in place.'' - The fixed guide wire (this is the movable force guide wire 1-t) and ・It is hollow to receive) is 9. Historically, the ablation collected at the tip of the catheter: i -1 It acts as a tokup for Koh Mu.

The catheter of the present invention has a catheter main body having a hole extending from a distal end to a proximal end. Consists of the body. A fixed guide wire is fixed to the distal end of the catheter body and is fixed to the distal end of the catheter body. It includes narrow passages extending from it. Both the catheter body and narrow passageway are movable. Facilitate the initial positioning of the catheter device by following instructions. Then, the above catheter For subsequent repositioning of the movable guide, leave the fixed guide wire in place. The wire is removed.

The ability to reposition the catheter after removal of the movable guidewire, in particular, When the catheter causes an ashernic reaction by occluding the coronary artery 17 It's advantageous. Utilization of the fixed guidewire described above may restore blood flow (aschc). mic condition) and immediately by using only the above fixed guide wire. 16. to reposition the catheter. (Doctor) =Return to category-chill-1.

In a first specific embodiment, the L distribution j~/del body is a flexible tube and the iT1' The distal end of the flexible tube includes a housing defined at 11 o, -, Fl. The guide wire is fixed at the distal end of the housing above (the second is fixed, the movable guide wire is the first For initial positioning, insert the tube, the 1-marked screw, and the guide wire into the tube. 11.1 The above housing is a cut lug blade, and 1″ source, ho, j,, 4s,,,) Tsubu, 1 supersonic reduction transducer including interventional or diagnostic elements such as In a second particular embodiment - the C7 inflation balloon is may be provided at the distal end of the catheter device for use without angioplasty. .

Brief description of the drawing FIG. 1 shows an example of a vascular catheter device constructed according to the principles of the present invention. FIG.

2 is a detailed cross-sectional view of the distal end of the catheter of FIG. 1; FIG.

FIG. 3 is a partial cross-sectional view of the distal end of the catheter fF of FIG. 1 shown in place within a blood vessel. ゛Yes FIG. 4 shows the distal end of an angioplasty balloon canal 9 constructed in accordance with the principles of the present invention. FIG.

FIG. 5 is a cross-sectional view of the distal end of an ultrasound imaging catheter constructed according to the principles of the present invention. It is.

Description of specific aspects The present invention provides a method for introducing, positioning, and subsequent repositioning of a catheter device within a caregiver's vascular system. We provide an improved method for making decisions.

The catheter of the present invention includes a catheter body and a fixed guide fixed to the distal end thereof. The fixed guide wire is configured to receive a movable guide wire. Including alleyways. The catheter body typically has a housing fixed to its distal end. The fixed guide wire is made of an elongated flexible tube having a housing. Fixed to A wire hole is formed between the flexible tube and the housing, and the wire hole is formed between the flexible tube and the housing. Ear holes open into the narrow passageway within the fixed guidewire to separate the catheter. Allows insertion onto a movable guidewire.

The method of the present invention first involves the distal end of the movable guidewire being positioned within the vascular system. The movable guide wire is introduced using the conventional method so that it is proximal to the site. Become. The catheter device is then attached to the distal end of the catheter or housing. the movable guidewire until it reaches the site of interest. then on The movable guide wire is removed and the catheter is removed due to the presence of the movable guide wire. Avoid being disturbed. However, under certain conditions, the above movable No guidewire reintroduction required (remaining guidewire Subsequent repositioning of the catheter is possible. Additionally, remove the movable guide wire above. After this, the wire hole can be used for other purposes such as suction or irrigation.

The vascular catheter of the present invention can be used for a wide range of purposes including interventional and diagnostic techniques. . An interventional catheter constructed in accordance with the principles of the present invention [)S Patent No. 4.669.4 No. 69 and European Patent Application No. 163 502. Includes ablation catheter. The disclosures of the above patents and patent applications are incorporated herein by reference. It will be done. Balloon angioplasty catheter of the type described in US Pat. No. 4,323,071 Disclosures regarding Tell are included herein by reference. Also BP Patent Application No. 21755 Disclosure regarding laser ablation catheters of the type described in No. 05A is incorporated herein by reference. It is. A diagnostic catheter constructed in accordance with the principles of the present invention is referred to herein. Endoscopic catheters and ultrasound as described in US Pat. No. 4,794,931 Includes wave imaging catheter.

The movable guide wire used in the catheter device of the present invention is for introducing a vascular catheter. It may be of any standard construction commonly employed for this purpose. Normal, movable guy Dwire consists of a helical coil of wire formed on a tube core or solid wire. Ru. Such structures are described in US Pat. Nos. 4,215,703 and 4,724,846. No. 1, and references cited therein, the disclosures of which are hereby incorporated by reference. It is being done. Further, the above movable guide wire is disclosed in US Pat. No. 4,682,607. can be formed using the standard structures described in , the disclosure of which is incorporated herein by reference. Up In either of these configurations, the stiffness of the guidewire typically varies with length. The guidewire develops more flexibility at the distal tip corresponding to its longitudinal remainder. do. Optionally, the guidewire is made of polytetrafluoroethylene (PTFE). , polyurethane, etc., may be coated with a material that facilitates incorporation.

The length and diameter of the movable guide wire of the present invention may vary depending on the application; The guidewires used in coronary procedures have lengths ranging from approximately 125 to 200 cm. About 0. Grow diameters ranging from Ol to 0.025 inches. used for peripheral treatments The guide wires used have lengths ranging from approximately 60 to 200 cm and approximately 0.014 to 0.0 ,06 inches in diameter. The distal tip of the guidewire is typically Deflection to facilitate manipulation and advance the guidewire into the vasculature by conventional methods Or it can be curved.

The fixed guidewire used in the catheter configuration of the present invention is similar in some respects to the previous configuration. It is similar to this, but may be modified to receive the movable guide wire. especially, The fixed guide wire of the present invention has a wire hole formed in the catheter/chill main body. includes a narrow passageway that opens at the proximal end. This narrow passage is used during the introduction of the above catheter. The entire length of the fixed guide wire and the catheter body is connected to the movable guide wire. It may be open at its distal end to allow passage of.

The outer diameter of the fixed guidewire and the inner diameter of the axial passageway are the same as the intended diameter of the catheter. Depends on the intended purpose. For coronary procedures, the outer diameter of the fixed guidewire is typically It ranges from about 0.016 to 0.05 inches, with an inner diameter of about 0.012 to 0.05 inches. ．． It is in the range of 0.03 inches. For peripheral procedures, the outer diameter of the above fixed guidewire is It ranges from approximately 0.02 to 0.04 inches. The length of the fixed guide wire above is approximately 5cm from the bottom I.

Usually in the range of 2 to 3 cm. Usually, the fixed guide wire is connected to the movable guide wire. substantially straight to facilitate entry onto the dwyer. However, to a certain extent Curvature or deflection of the fixed guide wire when inserted over the movable guide wire It is acceptable as long as the two do not bind or combine. Especially after the fixed guide wire is If it is made of a smooth material such as the plastic mentioned above, the tip may be curved. Finally. However, this curvature is caused by the fact that the fixed guide wire is different from the movable guide wire. Straightens when placed on top. Typically from multiple branches of the vascular system More than within the only branch of the vasculature that is not used to move the catheter above Avoid bending or deflecting the fixed guide wire as it is used for limited movement only. There is no need to give it.

The fixed guidewire is generally more comparable than the catheter body to which it is attached. It has great flexibility. Usually, the fixed guidewire mentioned above is a helical coil, and the Optionally, a flat safety rib further forms a channel for receiving the movable guide wire. formed on a tube or tube. Furthermore, the fixed guide wire may be a metal bellows or thermoplastic or thermoset with radioactive fillers such as barium or bismuth It may be made of plastic.

Referring to FIGS. 1-3, a catheter device lO constructed in accordance with the principles of the present invention From a catheter body that includes a flexible tube 12 extending from a proximal end I4 to a distal end 16. Become. A proximal housing 18 is secured to the proximal end of the flexible tube 12 and includes an inflation boat. 20 and an irrigation boat 22. Distal housing 24 is secured to distal end 16 of tube 12. and the drive member 26 extends through the central hole of the flexible tube 12 from the proximal housing 18. and extends therethrough to the distal housing 24. The driving member 26 is connected to the connecting member 28 and the positioning rail. It terminates within bar 30. A connecting member 28 is provided for rotation of the driving member. No. 4,771.774 (the disclosure of which is hereby incorporated by reference). For installation in a drive unit equipped with a motor such as the one described in The positioning lever 30 is attached to the top of the flexible tube 12 by the user. The drive member can be moved in the axial direction. A circular cutting blade 32 is driven. attached to the distal end of moving member 26 and formed within one side of housing 24; axially elongated opening 34 . inflatable bal A ring 36 is secured to the housing 24 on the opposite side of the opening 34. this bar The horn can be used to force the housing 24 into the atheroma area so that the atherosclerosis The object is inserted into the opening 34. In this way, the cutting blade 32 cuts the atheroma and advances the atheroma to the distal end of the housing 24. It can be used to move. Furthermore, the structure and operation of the cutting 10 will be explained later. Generally used in European Patent Application No. 163 502 and US Patent No. 4.699, No. 469, both inventions are incorporated herein by reference.

According to the invention, fixed guidewire 40 is fixed to the distal end of housing 24. and includes a passageway or hole 42 passing therethrough. The narrow passage 42 is located inside the housing 24. 4 and can be accommodated by the above-mentioned chill 10. Continuous disappearance; Conquest゛ ′　As further illustrated, The movable guide wire 48 passes sequentially through the bore 46 and the interior 44 within the hollow of the drive member 26. go through the department. However, in other configurations, the drive member 26 is not present and the movable guide The wire 48 communicates directly with a wire hole formed in the flexible tube of the catheter body. It may be something that

In particular, with reference to FIG. When positioned proximal to area A, the passageway 42 and the interior 44 of the housing 24 allow The dynamic guidewire 48 is removed. The cutting member 32 is , excise a portion S of the atheroma and deposit that portion at the distal end of the housing 24. It can be used by conventional methods to

The fixed guidewire 40 then acts as a trap to remove the wire from the housing 24. This prevents loss of the atherosclerotic portion S.

This is because the channel in the distal housing that receives the movable guidewire is relatively short. ``Over-the-Wye'' exposes the caregiver to the danger of empoly released from the catheter. After removal of movable guidewire 48, fixed guidewire The housing 24 of the catheter IO also includes a light wave guide for delivering laser energy. to carry other interventional elements such as ids and hot caps for transporting heat. It has become. In either case, the above catheter is used to directly apply heat to the atheroma. It can be used for thermal ablation treatment. The above housing is also fixed above Can be conveniently used for drug injection by releasing the drug from the guidewire into itself. Wear.

FIG. 4 depicts a balloon catheter 50 constructed in accordance with the principles of the present invention. This category US Pat. No. 4,323.0, the disclosure of which is hereby incorporated by reference. The structure is similar to the coaxial balloon catheter described in No. 71. Catheter 50 is medium From a central tube 52 and a second tube 54 expanding at its distal end to form a balloon component. Become. The second tube 54 further includes a balloon to enable inflation of the balloon component 56. forming the proximal end (not shown) of the tube. The second tube 54 is within the balloon component 56. formed around the central tube 52 at its distal tip 60 to enable sealing of the It is. The central hole 62 formed by the central tube 52 is flexible as shown in dotted lines. A wire hole is provided that can receive a dynamic guidewire 64. Fixed guide wire A wire 66 is fixed to the distal tip 60 and for receiving the movable guidewire 64. It also includes a passageway 68 that further defines a hole.

FIG. 5 shows an ultrasound imaging catheter 70 constructed according to the principles of the present invention. Ru. Imaging catheter 70 includes a flexible tube 72 and a distal housing 74. ultrasound The transducer 76 is provided at the front end inside the housing 74 and has a rotating mirror. 77 is located within the housing proximal to the transducer. mirror 77 is mounted on a rotational drive member 78.

The fixed guide wire 80 can be removably fixed to the housing 74 and has a thin wire passing therethrough. 82. The second axial passage 84 is formed within the distal end of the housing 74 and is a passageway. 86 and 88 are formed on both the transducer 76 and the mirror 77, respectively. . The drive member 78 is hollow and the movable guidewire 90 is thus The entire catheter assembly 70 may be accommodated as shown in FIG. Detachable The use of fixed guidewires is dependent on guidewire flexibility, length, and It is advantageous in that it allows you to change the length and diameter. Types listed here, disclosure here It is used as a reference.

The operation and construction of the ultrasound imaging catheter is updated from US Pat. No. 4,794,931. , the disclosure of which is incorporated herein by reference.

Although the above invention has been described in detail for ease of understanding, certain modifications have been appended. It is clear that the invention can be implemented within the scope of the claims.

FIG.

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Claims (49)

[Claims] 1. a catheter body having at least one aperture extending from the proximal end to the distal end; ,and a fixed guidewire fixed to the distal end of the catheter body, the fixed guide; the wire has an axial passage capable of receiving a movable guidewire; A vascular catheter comprising: 2. The catheter body is secured to an elongated flexible tube and a distal end of the flexible tube. the fixed guidewire is secured to the distal end of the housing. The vascular catheter of claim 1, wherein: 3. The fixed guide wire is removably fixed to the housing. Item 2: Vascular catheter. 4. Claim: wherein said fixed guidewire is permanently secured to said housing. 2 vascular catheter. 5. The vascular catheter of claim 2 further comprising an interventional or diagnostic element within the housing. Tell. 6. The vascular catheter of claim 1 further comprising an expansion balloon at its distal end. 7. The vein of claim 1 further comprising means for ablating the atheroma at its distal end. tube catheter. 8. The vascular catheter of claim 1 further comprising means for ultrasound imaging at its distal end. Tell. 9. 6. The vascular catheter of claim 5, wherein the interventional element is a cutting blade. 10. The vascular catheter of claim 5, wherein the diagnostic element is an ultrasound transducer. Le. 11. The vascular catheter of claim 1, wherein the fixed guidewire is a helical coil. 12. The vascular catheter of claim 1, wherein the fixed guidewire is a metal bellows. . 13. The vascular catheter of claim 1, wherein the fixed guidewire is a plastic tube. Le. 14. The fixed guidewire described above has an outer diameter ranging from approximately 0.016 to 0.06 inches. The vascular catheter of claim 1, comprising: 15. The fixed guidewire described above has an inner diameter in the range of approximately 0.012 to 0.04 inches. The vascular catheter of claim 1, comprising: 16. Claim 1, wherein the fixed guidewire has a length in the range of about 1 to 5 cm. vascular catheter. 17. a flexible tube having at least one hole extending from the proximal end to the distal end; the flexible tube has a proximal end and a distal end secured at its proximal end to the distal end of the flexible tube; a housing fixed to the distal end of said housing and having an axial passage passing therethrough; a fixed guidewire, and A movable guide wire extends through the hole of the flexible tube and the axial path of the fixed guide wire. Ya, A vascular catheter device comprising: 18. The fixed guide wire is detachably fixed to the housing. The vascular catheter according to claim 17. 19. The fixed guide wire is permanently fixed to the housing, claim Item 17: Vascular catheter. 20. 18. The vascular catheter of claim 17, further comprising an interventional element within the housing. 21. 18. The vascular catheter of claim 17, further comprising an expansion balloon at its distal end. 22. Claim 17 further comprising means for ablating the atheroma at its distal end. vascular catheter. 23. 18. The vascular cap of claim 17, further comprising means for ultrasound imaging at its distal end. Teter. 24. The vascular catheter of claim 20, wherein the interventional element is a cutting blade. Le. 25. The vascular catheter of claim 20, wherein the interventional element is an ultrasound transducer. Tell. 26. The vascular catheter of claim 17, wherein the fixed guidewire is a helical coil. . 27. The vascular catheter of claim 17, wherein the fixed guidewire is a metal bellows. Le. 28. The vascular catheter of claim 17, wherein the fixed guidewire is a plastic tube. Tell. 29. The fixed guidewire described above has an outer diameter ranging from approximately 0.016 to 0.06 inches. 18. The vascular catheter of claim 17, comprising: 30. The fixed guidewire described above has an inner diameter in the range of approximately 0.012 to 0.04 inches. 18. The vascular catheter of claim 17, comprising: 31. Claim 1, wherein the fixed guidewire has a length in the range of about 1 to 5 cm. 7 vascular catheters. 32. a flexible tube having at least one hole extending from the proximal end to the distal end; a flexible tube having a proximal end and a distal end secured at its proximal end to the distal end of the flexible tube; a housing extending from the proximal end thereof within the bore of the flexible tube to the housing; a drive member, said drive member having all axial and rotational movements relative to said housing; things, an intervention element fixed to the drive member within the housing, the drive member and the upper The interventional elements together form an elongated passageway capable of receiving a movable guidewire. a fixed guide wire secured to the distal end of the housing, a fixed guide wire secured to the distal end of the housing; The guide wire is in line with the passage through the drive member and the intervention element and is connected to the movable guide. having an elongated passageway capable of receiving a wire; A vascular catheter comprising: 33. The vascular catheter of claim 32, wherein the fixed guidewire is a helical coil. . 34. The vascular catheter of claim 32, wherein the fixed guidewire is a metal bellows. Le. 35. The vascular catheter of claim 32, wherein the fixed guidewire is a plastic tube. Tell. 36. The fixed guidewire described above has an outer diameter ranging from approximately 0.016 to 0.06 inches. 33. The vascular catheter of claim 32, comprising: 37. The fixed guidewire described above has an inner diameter in the range of approximately 0.012 to 0.04 inches. 33. The vascular catheter of claim 32, comprising: 38. 3. The fixed guidewire has a length in the range of about 1 to 5 cm. 2 vascular catheter. 39. The fixed guide wire is detachably fixed to the housing. Item 32 vascular catheter. 40. for removing atheroma on or within the housing. 33. The vascular catheter of claim 32, further comprising means. 41. A method for introducing a vascular catheter into a patient, the distal end of which is connected to the patient's pulse. positioning the movable guidewire proximal to the selected site within the ductal system, and The vascular catheter is introduced over the movable guidewire. includes a fixed guidewire at its distal end, said fixed guidewire being connected to said movable guidewire. having an elongated passageway for receiving the wire; A method characterized by: 42. After introducing the vascular catheter, the movable guidewire is removed, and After removal of the movable guidewire, the vascular catheter is opened using the fixed guidewire. 42. The method of claim 41, further comprising repositioning the terminal. 43. Intervention or diagnosis at selected sites within the vascular system using the vascular catheter described above 42. The method of claim 41, further comprising administering a treatment. 44. 42. The method of claim 41, wherein the interventional procedure comprises atherectomy. 45. 42. The method of claim 41, wherein the interventional procedure comprises atheroma expansion. 46. 42. The method of claim 41, wherein the interventional procedure includes imaging of an atheroma. 47. 44. The method of claim 43, wherein the interventional procedure comprises thermal ablation. 48. 44. The method of claim 43, wherein said interventional procedure comprises drug infusion. 49. The interventional procedure is to ablate the atheroma with a blade within the housing. at least a portion of the resected atheroma is connected to the fixed guide wire. 44. The method of claim 43, wherein the method is trapped within an elongated passageway of.