Patent Application
20130184805
The disclosure here generally pertains to an introducer sheath and a placement device for a blood vessel treatment instrument. More specifically, the disclosure involves an introducer sheath whose overall length can be shortened, a placement device for a blood vessel treatment instrument, and a method for shortening an introducer sheath.
At the time of inserting a catheter into a blood vessel for diagnosis or treatment, in general, an introducer sheath is used as an access route which interconnects the exterior of the living body and the inside of the blood vessel. A primary purpose of this is to reduce the damage to a blood vessel which damage is generated, at the time of sequentially using a plurality of catheters, due to the process in which the catheters different in diameter are inserted into and withdrawn from a blood vessel puncture part a plurality of times. A secondary purpose is to ensure relatively easy insertion at the time of inserting a catheter having a non-smooth surface, such as a large-diameter balloon catheter or a balloon-expandable stent, and to avoid damage to a blood vessel.
On the other hand, in the case of a stent graft system used for treatment of aortic aneurysm (hereinafter referred also to simply as “system”), an introducer sheath is rarely used and the system is often inserted directly into a blood vessel. The stent graft system is a treatment device used in a stent graft insertion procedure in which a stent graft is carried to a treatment site where the aneurysm is present, then the stent graft is allowed to expand by its self-expanding force and is placed indwelling in situ. The stent graft system is by far larger than common catheters in shaft outside diameter, and this is why the introducer sheath is rarely used therewith.
A general stent graft system has an outer tube for housing a stent graft on the inner circumference of a distal portion thereof, and an inner tube slidably inserted inside the outer tube. The general stent graft system is so configured that with the outer tube slid proximally relative to the inner tube, the stent graft is allowed to expand radially by its self-expanding force, to be placed indwelling in a blood vessel. An example is disclosed in Japanese Patent Laid-open No. 2005-270395.
Most of the products of stent graft are of self-expanding type. As for the outer surface of the stent graft's shaft section to be inserted into the living body, in many cases, the stent part is also housed in a smooth tube, like in the cases of other self-expandable stents. Therefore, non-use of an introducer sheath at the time of inserting a stent graft system into a blood vessel would not produce the problem of damage to the blood vessel.
In the stent graft insertion procedure, however, there are cases where after the placement of a stent graft, another stent graft is added as an extension graft. There are also cases where a balloon catheter is inserted for the purpose of fixing the stent graft to the blood vessel more firmly. Therefore, there still remains the problem of damage to the blood vessel due to the repetition of insertion and withdrawal.
To address such a problem, there is a method in which the outer tube of the system is employed as an introducer sheath for other treatment device(s). In this method, after the first stent graft is inserted and placed indwelling, the outer tube (and the guide wire) of the system is left in the blood vessel, whereas the other component parts (inner tube, etc.) constituting the system are all pulled out. Then, the outer tube thus left in the blood vessel is used as an introducer sheath at the time of inserting other treatment device(s). This prevents spreading of the damage to the blood vessel puncture part at the time of inserting additional stent graft(s) or balloon catheter(s).
In most of the stent graft systems according to the art as above-described, it is necessary to insert the outer tube to the position (depth) where the stent graft is to be actually placed indwelling. Therefore, the overall length of the system inclusive of the outer tube is greater, as compared with common introducer sheaths. Therefore, in the case of using the outer tube of the system as it is as an introducer sheath at the time of inserting other treatment device, the treatment device must have an overall length not less than the overall length of the outer tube. Thus, treatment devices which are short in overall length cannot be used. In addition, a treatment device with an excessively large length is difficult to manipulate.
The disclosure here provides an introducer sheath which can be used as an introducer sheath for a short treatment device and which eliminates the need to use an excessively long treatment device, and also to provide a placement device for a blood vessel treatment instrument, and a method for shortening an introducer sheath.
The introducer sheath into which a long shaft is inserted, includes: a flexible tube-shaped sheath body; and a hub into which a proximal portion of the sheath body is inserted, wherein the hub takes-up a proximal portion of the sheath body into the hub while slitting the proximal portion of the sheath body, whereby the length of extension of the sheath body from the hub can be shortened.
It is possible, after the introducer sheath is employed as an outer tube of a blood vessel treatment instrument placement device to be used for placing a blood vessel treatment instrument (stent graft), to shorten the overall length of the sheath body of the introducer sheath. Therefore, a treatment device shorter than the overall length of the original introducer sheath can be inserted into a blood vessel by utilizing the introducer sheath. In addition, it is unnecessary to use an excessively long treatment device.
The hub preferably has a cutting section by which slits along an axial direction are formed in the sheath body; and a plurality of take-up shafts are preferably provided to respectively take-up terminal pieces of the sheath body separated by the slits.
By taking-up the terminal portions of the sheath body using the take-up shafts, it is possible to draw the sheath body into the hub and simultaneously to form slits in the sheath body by the cutting section. Therefore, take-up of the sheath body and formation of the slits are concurrently carried out by rotating the take-up shafts, so that the effective length of the sheath body can be easily shortened by a single operation (rotating operation).
The cutting section preferably forms the slits in portions of the sheath body which are on opposite sides with respect to a circumferential direction, and the plurality of take-up shafts are two take-up shafts disposed at positions spaced from each other along the direction of splitting of the sheath body by the slits.
The proximal portion of the sheath body is cut into two by the cutting section, and the resulting terminal ends are taken up by the two take-up shafts spaced from each other in the direction of splitting of the sheath body. Therefore, the sheath body can be rather smoothly taken up with a small number of component parts.
The cutting section preferably includes a plurality of cutting blades by which the slits are formed in circumferential-directionally different portions of the sheath body. The cutting resistance at the time of drawing the sheath body into the hub can thus be reduced. This helps ensure that the torque required at the time of taking up the terminal portions of the sheath body can be reduced, and the taking-up operation can be carried out more easily.
The hub preferably has an interlocking mechanism by which the plurality of take-up shafts are rotated in an interlocked manner. This allows all the take-up shafts to be rotated simultaneously, so that the separated terminal portions, resulting from cutting of the sheath hub, can be taken up in a well-balanced manner.
The hub preferably has rotation restraining mechanisms for inhibiting the take-up shafts from rotating in an unwinding direction. The take-up shafts are thus not rotated in the direction for unwinding the terminal portions of the sheath body having once been taken up, so that the sheath body is inhibited from moving in the extending direction relative to the hub. Therefore, the slits formed by the cutting section would not be exposed to the outside of the hub, so that blood can be prevented from leaking to the exterior of the hub through the slits.
The hub also preferably includes a hub body provided with a hollow section in which the take-up shafts and the proximal portion of the sheath body are housed. A rotational operating section which is rotationally operated from outside of the hub body can also be provided to thereby rotate the take-up shafts. The hub body is preferably configured to be liquid-tight so that a liquid flowing into the inside of the hub through the sheath body does not leak to the exterior. This helps ensure that even when blood flows into the hub through the sheath body, the blood is prevented from leaking to the exterior of the hub.
In accordance with the disclosure here, an introducer sheath into which is insertable an elongated shaft includes a hub possessing a distal end, a flexible tubular sheath body possessing a proximal-most portion and a distal-most portion; and movable shortening member mounted on the hub. The proximal-most portion of the sheath body includes a plurality of axially extending slits which circumferentially separate a plurality of terminal portions of the sheath body, with at least one of the terminal portions being connected to the shortening member, and the distal-most portion of the sheath body extending distally beyond the distal end of the hub. The shortening member is movable relative to the hub to move the sheath body relative to the hub and shorten an axial extent to which the distal-most portion of the sheath body extends distally beyond the distal end of the hub.
Another aspect of the disclosure here involves a blood vessel treatment instrument placement device by which a self-expanding blood vessel treatment instrument is delivered to and placed indwelling in a desired treatment site in a blood vessel. The blood vessel treatment instrument placement device comprises an introducer sheath having a sheath body for housing the blood vessel treatment instrument on an inner circumference of a distal portion of the sheath body, and an inner tube slidably positioned inside the sheath body. The introducer sheath comprises: a flexible tube-shaped sheath body possessing a proximal portion and a distal portion; and a hub in which the proximal portion of the sheath body is positioned with the distal portion of the sheath body extending distally beyond a distal end of the hub; with the hub being configured to take-up the proximal portion of the sheath body into the hub while slitting the proximal portion of the sheath body to shorten a length of the sheath body extending distally beyond the distal end of the hub.
After placing the blood vessel treatment instrument, it is possible, by pulling the inner tube out of the sheath body and shortening the effective length of the sheath body, to employ the introducer sheath as an introducer sheath for a treatment device which is shorter than the overall length of the original introducer sheath. In addition, it is unnecessary to use an excessively long treatment device.
Another aspect of the disclosure involves a method for shortening an introducer sheath in which a long shaft is inserted. The method includes slitting a proximal portion of a sheath body positioned in a hub to form at least two terminal portions at the proximal portion of a sheath body, drawing the sheath body into the hub in which the proximal portion of the sheath body is positioned, and taking up the terminal pieces of the sheath body.
Set forth below is a description of an introducer sheath, a blood vessel treatment instrument placement device, and a method for shortening an introducer sheath according to the disclosure here. For convenience of description, the right side in
The blood vessel treatment instrument placement device 10 (hereinafter referred also to simply as “placement device 10”) shown in
As shown in
The introducer sheath 14 has a sheath body 18 and a hub 20. The sheath body 18 is an outer tube which houses the stent graft 12 on an inner circumference of a distal portion of the outer tube. The sheath body 18 is formed from a flexible (elastic) material, and has a lumen having a substantially constant inside diameter along the axial direction of the sheath body. Examples of the material of the sheath body 18 include bio-compatible synthetic resins selected from among polyamides, polyethylene, fluoro-resins, polyimides and the like.
The hub 20 is a hollow member provided at (connected to) a proximal portion of the sheath body 18, and the hollow part of the hub 20 communicates with the lumen of the sheath body 18. The configuration of the hub 20 will be described in more detail below.
The inner tube 16 is inserted in the introducer sheath 14 in an axially slidable manner, and includes an inner tube body 22 and a hub 24. The inner tube body 22 is a flexible pipe-shaped body longer than the sheath body 18, and is provided therein along its axial direction with a guide wire lumen in which a guide wire is inserted. The inner tube body 22 has a maximum outside diameter not greater than the inside diameter of the sheath body 18 of the introducer sheath 14. Therefore, the inner tube body 22 can be pulled out of the sheath body 18 and the hub 20.
The inner tube body 22 is formed, in an outer circumferential portion near a distal portion of the inner tube body 22, with an annular groove 26 functioning as a housing section in which the stent graft 12 is housed or positioned. In
In performing a stent graft insertion procedure by use of the placement device 10 configured as above, the placement device 10 in the state as shown in
The introducer sheath 14 is so configured that the inner tube 16 can be pulled out. Further, in order that the introducer sheath 14 is applicable also to short other treatment devices (for example, a balloon catheter), it is so configured that the effective length of the sheath body 18 (the length of extension of the sheath body 18 from the hub 20) can be shortened. In
As shown in
So that the amount by which the effective length of the sheath body 18 has been shortened can be seen, graduations 36 with numerals (numerical indicia) are provided on the outer circumferential surface of a proximal portion of the sheath body 18. The graduations, in cooperation with a distal member 40 which will be described later, indicate the length by which the sheath body 18 has been shortened. This point will be described later.
The hub body 31 includes a trunk member 38, the distal member 40, and a proximal member 42. The trunk member 38 has a hollow configuration. As shown in
The distal-side opening 46 is a cylindrical hole which extends toward the distal side from the hollow section 44 and is approximately equal in diameter to the outer shape of the sheath body 18. The proximal side of the sheath body 18 is inserted through the distal-side opening 46. The proximal-side opening 48 is a cylindrical hole which extends toward the proximal side from the hollow section 44 and is approximately equal in diameter to the outer shape of the inner tube 16. The distal-side opening 46 and the proximal-side opening 48 are coaxial with each other, for permitting the inner tube 16 to be inserted through the distal-side opening 46 and the proximal-side opening 48.
The distal member 40 is a hollow cylindrical member having an inside diameter approximately equal to the diameter of the outer shape of the sheath body 18, and has a flange section 52 on the proximal side. The flange section 52 is fixed to the distal component section 50 by a fixing part or parts 51 such as a screw or screws.
The distal end face of the distal member 40 indicate the length by which the sheath body 18 has been shortened, in cooperation with the graduations 36 imparted to the outer circumferential surface of the sheath body 18. Specifically, when the sheath body 18 is in the initial state, a zero position of the graduations 36 (the graduation at the most proximal side) coincides with the distal end face of the distal member 40.
Between the flange section 52 of the distal member 40 and the distal component section 50, there is disposed a ring-shaped seal member 54 formed of an elastic material. An inner circumferential surface of the seal member 54 and an outer circumferential surface of the sheath body 18 are in secure contact with each other, over the whole circumference of the inner circumferential surface of the seal member 54 and the outer circumferential surface of the sheath body 18. This helps ensure liquid-tight sealing between the inner circumferential surface of the hub body 31 and the outer circumferential surface of the sheath body 18, at a distal-side portion of the hub body 31.
The material constituting the seal member 54 is not particularly restricted. Examples of the material which can be used include various rubbers such as natural rubber, butyl rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, and silicone rubber. Incidentally, for seal members 56, 58 and 60 which will be described later, also, the materials mentioned above as material for the seal member 54 can be used.
The proximal member 42 is a circular disk-shaped member having an opening 62 approximately equal in diameter to the outer shape of the inner tube 16. The proximal member 42 is fixed to a rear wall 64 of the trunk member 38 by a fixing part or parts 66 such as a screw or screws. Between the proximal member 42 and the rear wall 64 is disposed a ring-shaped seal member 56 which is formed from an elastic material. An inner circumferential surface of the seal member 56 and an outer circumferential surface of the inner tube 16 are in secure contact with each other, over the whole circumference of the inner circumferential surface of the seal member 56 and the outer circumferential surface of the inner tube 16. This helps ensure liquid-tight sealing between the inner circumferential surface of the hub body 31 and the outer circumferential surface of the inner tube 16, at a proximal-side portion of the hub 31.
In order that another treatment device is smoothly guided to the distal-side opening 46 at the time of inserting the treatment device from the proximal side, the trunk member 38 is provided with a tubular guide member 68 in the hollow section 44 of the trunk member 38. A proximal portion 68a of this guide member 68 is formed in a flare shape spreading toward the proximal side so that the distal end of the treatment device is smoothly inserted through the proximal portion 68a of this guide member 68. To simplify the illustration in
When the inner tube 16 is pulled out of the introducer sheath 14 in the condition where the introducer sheath 14 is inserted in a blood vessel, blood flows into the hollow section 44 through the sheath body 18. In view of this, as shown in
In the condition where the inner tube body 22 is inserted, as indicated by solid lines in
Materials for forming the trunk member 38, the distal member 40 and the proximal member 42 are not particularly limited. For example, various metallic materials and various plastics and the like can be used singly or in combination.
As shown in
The two cutting blades 72, 74 are disposed at positions between which the sheath body 18 interposed, with their cutting edges oriented toward the side (outer surface) of the sheath body 18. The cutting edges cut slits along the axial direction (axially extending slits) in the sheath body 18. The material constituting the cutting blades 72, 74 is not specifically restricted; for example, various metallic materials (stainless steel, etc.) can be used. With the cutting blades 72, 74 formed from a metallic material, it is easy to form the cutting edges.
As shown in
The cutting edges of the cutting blades 72, 74 protrude from the inner ends of the through-holes 76, 78 (namely, from the inner surface of the distal-side opening 46) by an amount corresponding roughly to the material thickness (pipe wall thickness) of the sheath body 18, while also not making contact with the inner tube body 22. When the sheath body 18 is moved proximally, therefore, the sheath body 18 is cut by the cutting blades 72, 74 along the axial direction, but the inner tube body 22 is not cut.
Thus, the cutting blades 72, 74 are positioned by being inserted into and fixed in the through-holes 76, 78; therefore, the amounts of protrusion of the cutting edges from the inner circumferential surface of the distal-side opening 46 can be accurately set, and this state can be securely maintained. While each of the through-holes 76, 78 in the example shown extends in a direction orthogonal to the axis of the distal-side opening 46, it may extend in a direction inclined relative to the axis.
The configuration for disposing and fixing the cutting blades 72, 74 in the trunk member 38 is not restricted to the one shown in
As shown in
The two take-up shafts 30, 32 in the example shown are arranged at positions spaced from each other along the direction of splitting or separation (the vertical direction in
As shown in
As shown in
In addition, at the other-side end portions of the take-up shafts 30, 32, an operating section 34 to be operated to rotate the take-up shafts 30, 32 is provided outside of the hub body 31. In the configuration shown, the operating section 34 includes two operating wheels 100 and 102 which can be rotationally operated. As shown in
In this embodiment, the hub 20 further has an interlocking mechanism 106 by which rotations of the take-up shafts 30, 32 are interlocked with each other. In the configuration shown, the interlocking mechanism 106 includes intermeshing gears 107, 108 at outer circumferential portions of the operating wheels 100, 102. This ensures that when one of the two operating wheels 100, 102 is rotated, the other is rotated in the reverse direction.
The introducer sheath 14 configured as above-described can, after a stent graft insertion procedure, be used as an introducer sheath for other treatment device (for example, a balloon catheter) by a method in which the inner tube 16 is pulled off on the proximal side and then the effective length of the sheath body 18 is shortened. Before using the introducer sheath 14 disclosed here by way of example, the introducer sheath 14 is configured in the manner shown in
In order to shorten the effective length of the sheath body 18, it is necessary only to rotate the operating section 34. Specifically, when the operating wheels 100, 102 are rotated, the take-up shafts 30, 32 connected to the operating wheels 100, 102 rotate and the terminal pieces 28a, 28b are taken up on the take-up shafts 30, 32, simultaneously when the slits are formed by the two cutting blades 72, 74. That is, the cutting blades 72, 74 cut the sheath body 18 so that the axial extent of the slits, originally existing on the proximal portion of the sheath body 18 as shown in
As has been described above, the introducer sheath 14 ensures that after it is employed as an outer tube of the placement device 10 used for placement of the blood vessel treatment instrument (stent graft 12), the overall length of the sheath body 18 can be shortened. Therefore, a treatment device shorter than the overall length of the original introducer sheath 14 can be inserted into a blood vessel by utilizing the introducer sheath 14 shortened in effective length. In addition, it is unnecessary to employ a treatment device that is longer than needed.
According to the introducer sheath 14, it is possible, by taking up the terminal pieces 28a, 28b of the sheath body 18 by the plurality of take-up shafts 30, 32, to draw the sheath body 18 into the hub 20 and simultaneously form a cut or cuts in the sheath body 18 by the cutting section 28. Therefore, by rotating the take-up shafts 30, 32, take-up of the sheath body 18 and formation of the slits can be carried out concurrently. Accordingly, the effective length of the sheath body 18 can be relatively easily shortened by a single operation (rotating operation).
In addition, in the introducer sheath 14, a proximal portion of the sheath body 18 is torn up or split into two by the cutting section 28, and the terminal ends thus torn or split apart are taken up by the two take-up shafts 30, 32 spaced from each other in the direction of splitting of the sheath body 18. Therefore, the sheath body 18 can be relatively smoothly taken up by a small number of component parts.
The sharp cutting blades 72, 74 in the introducer sheath 14 are used as the cutting section 28, whereby the cutting resistance at the time of drawing the sheath body 18 into the hub 20 can be reduced. This helps make it possible to reduce the torque required for taking up the terminal pieces 28a, 28b of the sheath body 18, and to perform the taking-up (winding) operation more easily.
Furthermore, in the introducer sheath 14, the action of the interlocking mechanism 106 helps ensure that all the take-up shafts 30 and 32 can be simultaneously rotated by only rotationally operating either one of the operating wheels 100 and 102. Consequently the terminal pieces 28a and 28b torn apart can be taken up in a well-balanced manner. Accordingly, the sheath body 18 can be smoothly drawn into the inside of the hub body 31, and the taking-up operation can be carried out more easily.
In the introducer sheath 14, each part is sealed liquid-tight by the seal members 54, 56, 58, 60. Therefore, even when blood flows into the hub 20 through the sheath body 18, the blood is prevented from leaking to the exterior of the hub 20.
The introducer sheath 14a shown in
In the case of this embodiment, the take-up shafts 30, 32 are interlocked with each other through the gears 107, 108. Therefore, it is possible to employ a construction in which only one of the one-way clutches 104A, 105A is provided.
In the introducer sheath 14a configured as above-mentioned, the take-up shafts 30, 32 are inhibited by the rotation restraining mechanisms 104, 105 from rotating in the unwinding direction. This helps ensure that the terminal pieces 28a, 28b of the sheath body 18 which have once been taken up would not be unwound, so that the sheath body 18 is inhibited from moving in the extending direction (distal or forward direction) relative to the hub 20. Therefore, the slits formed by the cutting section 28 would not be exposed to the outside of the hub 20. Accordingly, blood can be prevented from leaking to the exterior of the hub 20 through the slits.
The configuration of the rotation restraining mechanisms 104, 105 is not restricted to the one-way clutches 104A, 105A. The configuration may be a ratchet mechanism having an engagement section for engagement with at least one of the gears 107, 108. The ratchet mechanism in this case is so configured that the engagement section is elastically displaced to ride over teeth of the gear(s) 107, 108 at the time of rotation in the winding direction of the take-up shafts 30, 32, whereas the engagement section does not ride over the teeth of the gear(s) 107, 108 at the time of rotation in the reverse direction to the winding direction. This configuration inhibits the take-up shafts 30, 32 from reverse rotation.
The introducer sheaths 14, 14a described above is configured so that the number of portions in which the slits are formed by the cutting section 28 is two, but the introducer sheaths are not limited in this regard. It is possible that the introducer sheaths 14, 14a can be configured so that the number of slits and the number of divided portions formed by the cutting section 28 is three or more. In other words, the proximal portion of the sheath body 18 may be taken up after being torn up or split into (divided into) three or more portions with three or more slits. Where the slits formed are three or more, the number of terminal pieces formed from the sheath body 18 is the same as the number of slits. In this case, a configuration may be adopted in which two take-up shafts 30, 32 are provided in the same manner as above, and two of the plural (three or more) terminal pieces are taken up by the take-up shafts 30, 32. Alternatively, a plurality of take-up shafts can be provided that are equal in number to the number of terminal pieces and the number of slits. In this case, the axes (rotational center lines) of the take-up shafts may not necessarily be parallel to one another.
In the introducer sheath 14b shown in
In a hub body 31 in the example shown, two linear (filamentous) members 122, 124 are disposed substantially in parallel so that plural (four) slits are formed in the sheath body 18 on the side of the distal end of the hub body 31 relative to take-up shafts. Therefore, a proximal portion of the sheath body 18 is split into four terminal pieces 126a, 126b, 126c, 126d.
In the example shown, the two linear members 122, 124 are fixed to a distal-side wall surface 128 of a trunk member 38 in an appropriate manner, and are disposed to traverse a distal-side opening 46 (shown in
In the condition where an inner tube body 22 is inserted in the sheath body 18, a part between both ends of each of the linear members 122, 124 is interposed between the sheath body 18 and the inner tube body 22. The two linear members 122, 124 are disposed at positions spaced from each other in the axial direction of the take-up shafts 30, 32 in such a manner as to extend in a direction substantially orthogonal to the axial direction of the take-up shafts 30, 32. Therefore, as shown in
In order to shorten the effective length of the sheath body 18 in the introducer sheath 14b, it suffices to rotate an operating section 34, like in the introducer sheath 14 shown in
While the terminal pieces 126a, 126c are taken up by the take-up shafts 30, 32 as above-mentioned, the other terminal pieces 126b, 126d are not taken up. However, the terminal pieces 126b, 126d are flexible and can be rather easily deformed when an external force acts on the terminal pieces 126b, 126d. Therefore, the terminal pieces 126b, 126d are deformed inside the hollow section 44 upon making contact with an inner wall constituting the hollow section 44, during when the terminal pieces 126a, 126c are taken up by the take-up shafts 30, 32. Accordingly, take-up of the terminal pieces 126a, 126c by the take-up shafts 30, 32 would not be hampered.
In order to respectively take up the terminal pieces 126b, 126d, the hub body 31 may be further provided with other two take-up shafts. In this case, the take-up shafts for taking up the terminal pieces 126b, 126d are provided at positions which are on the side of the distal end or proximal end of the hub body 31 in relation to the take-up shafts 30, 32 and which are on opposite sides with reference to the axis of the hub 20 (the axis of the distal-side opening 46 and the proximal-side opening 48 (see
In
The introducer sheath 14b shown in
The detailed description above describes features and aspects of embodiments, disclosed by way of example, of an introducer sheath, a placement device for a blood vessel treatment instrument, and a method for shortening an introducer sheath. But the invention is not limited to the precise embodiments and variations described and illustrated. Various changes, modifications and equivalents could be effected by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims. It is expressly intended that all such changes, modifications and equivalents which fall within the scope of the claims are embraced by the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2010-217881 | Sep 2010 | JP | national |
This application is a continuation of International Application No. PCT/JP20011/065757 filed on Jul. 11, 2011 and claims priority to Japanese Application No. 2010-217881 filed on Sep. 28, 2010, the entire content of both of which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2011/065757 | Jul 2011 | US |
| Child | 13785491 | US |
