Abstract:
The releasable torque device obviates the need for removal of the wire introducer in order to torque or manipulate a vascular or other guide wire and/or catheter in a medical procedure, and further obviates the need to remove the torque device for wire and/or catheter introduction. The device may include a base cylinder and an inflation cylinder defining a variable fluid volume therebetween. As the inflation cylinder is pushed toward the base cylinder, the fluid is forced through a port in the inner wall of the inflation cylinder and between a tubular inner cylinder and an inflatable guide wire grip within the inner cylinder to squeeze the grip onto the guide wire passing axially therethrough. Alternatively, the device only has a central tube and an inflatable guide wire grip therein, using a remotely disposed fluid pump and reservoir supplying fluid to the tube and guide wire grip.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates generally to medical devices and instruments, and particularly to a releasable torque device that selectively grips and releases a guide wire passing through the device to provide for both introduction and torsional manipulation of the guide wire. 
         [0003]    2. Description of the Related Art 
         [0004]    Guide wires are frequently used in various endovascular surgical fields to guide and position a catheter, stent, or other tubular device (lumen) in the body of a patient. These guide wires must be manipulated as they are passed through the vascular, urinary, or other system in the body, in order to position the distal end of the guide wire (and thus the catheter or other lumen) properly in the body. This is generally done by twisting or torqueing the guide wire to steer it through the vascular system as desired. 
         [0005]    Guide wires are generally introduced into a catheter and into the body by a device known as an introducer. The conventional introducer is a separate component from the torque device used to torque or steer the guide wire and catheter. Conventional torque devices must be removed from the guide wire and catheter in order for the introducer to be used, and the introducer must be removed from the guide wire and catheter assembly in order for the torque device to be secured to the guide wire and/or catheter for their manipulation. 
         [0006]    Thus, a releasable torque device solving the aforementioned problems is desired. 
       SUMMARY OF THE INVENTION 
       [0007]    The releasable torque device is a rigid tubular component having an elongate, cylindrical, selectively inflatable guide wire grip therein. The rigid tube and guide wire grip together define an axially elongate toroidal configuration. The guide wire grip may be selectively expanded inside the surrounding tube to squeeze the guide wire grip onto a guide wire inserted through the axially open center of the guide wire grip, thereby permitting the guide wire to be torqued by rotating the releasable torque device. 
         [0008]    In one embodiment, the releasable torque device includes a base cylinder, the wall of the cylinder having an annular slot formed therein that extends axially for a portion of the length of the cylinder. An inflation cylinder has parallel and coaxial cylindrical walls and an annular closed end between the coaxial walls, the outer cylindrical wall fitting closely within and sliding telescopically in the slot defined in the base cylinder. The inner cylindrical wall of the inflation cylinder is the rigid tube surrounding the inflatable guide wire grip. The inner cylindrical wall has a port defined therein, permitting fluid flow through the inner cylindrical wall to inflate the guide wire grip. As the inflation cylinder is pushed toward the base cylinder, the volume of space between the two coaxial walls and annular closed end of the inflation cylinder is compressed by the base cylinder, forcing any fluid therein through the port to inflate the inflatable guide wire grip. This squeezes the guide wire grip onto the guide wire to permit the guide wire to be torqued by rotating the introducer. 
         [0009]    Another embodiment dispenses with the base cylinder and inflation cylinder, leaving only the rigid tube having the inflatable guide wire grip therein. A remotely located fluid pump and reservoir is actuated to supply fluid pressure to the volume between the tube and the guide wire grip for operation of the device. 
         [0010]    The guide wire grip may have a high friction guide wire contact surface to enhance the clamping action of the guide wire grip on the guide wire. Also, instead of surrounding the guide wire, the guide wire grip may subtend only a portion of the inner wall of the surrounding tube, clamping the guide wire against the wall of the tube when inflated. These various embodiments may be combined in any practicable manner as desired. 
         [0011]    These and other features of the present invention will become readily apparent upon further review of the following specification and drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1A  is an enlarged environmental perspective view in section of a releasable torque device according to the present invention, shown with a guide wire freely passing therethrough, the grip being deflated. 
           [0013]      FIG. 1B  is an enlarged environmental perspective view in section of the releasable torque device of  FIG. 1A , showing the grip inflated to clamp the guide wire for manipulation thereof. 
           [0014]      FIG. 1C  is a detail view of area  1 C of  FIG. 1B . 
           [0015]      FIG. 2  is an enlarged environmental perspective view in section of the releasable torque device of  FIG. 1 , wherein the inwardly facing surface of the guide wire grip is provided with a high friction surface and an optional second inflation port. 
           [0016]      FIG. 3  is an enlarged environmental perspective view in section of an alternative embodiment of a releasable torque device according to the present invention, wherein the guide wire grip subtends only a portion of the inner wall of the central passage. 
           [0017]      FIG. 4  is an enlarged environmental perspective view in section of another alternative embodiment of a releasable torque device according to the present invention, having a single rigid cylinder and an external inflation pump. 
           [0018]    Similar reference characters denote corresponding features consistently throughout the attached drawings. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0019]    The releasable torque device provides for the manipulation of a catheter guide wire without need to remove the introducer to apply a separate guide wire torqueing device. Various embodiments are described herein. 
         [0020]      FIGS. 1A and 1B  of the drawings illustrate two different operative states for a releasable torque device  10 , hereinafter referred to as “device  10 .” It will be understood that the device  10 , as shown in  FIGS. 1A and 1B , is greatly enlarged for clarity in the drawings. The device  10  comprises an elongate rigid central tube  12  having a first end  14 , an opposite second end  16 , and an inner surface  18  (the tube  12  is “rigid” in the sense that it is made from an inflexible material; the tube  12  may be slidably disposed as part of an assembly). An inflation port  20  is defined in the wall of the tube  12  adjacent its first end  14 , the function of the inflation port  20  being described further below. 
         [0021]    An elongate, tubular, inflatable guide wire grip  22  is installed concentrically within the rigid central tube  12 , forming an inner liner that subtends substantially the entire inner surface  18  of the tube  12 . The guide wire grip  22  has an elongate toroid configuration when inflated, defining an axially open guide wire passage  24  that extends completely through the length of the guide wire grip  22  and the surrounding rigid tube  12 . The guide wire grip  22  has mutually opposed first and second ends  26  and  28  that are sealed to the inner wall  18  of the rigid tube  12  at the respective first and second ends  14  and  16  thereof.  FIG. 1C  is a detail view showing attachment of the first end  26  of the guide wire grip to the inner wall or surface  18  of the rigid tube. The guide wire grip  22  is formed of a suitable elastomeric material, such as the material used in the manufacture of balloons used in vascular medical procedures. The guide wire grip  22  includes a guide wire contact surface  30 , which preferably has sufficient friction to grip a guide wire  32  removably disposed through the center of the rigid tube  12  and the guide wire grip  22 . The guide wire grip  22  and the surrounding tube  12  are of substantially identical configurations in  FIGS. 1A ,  1 B,  1 C,  2 , and  4 . An alternative guide wire grip configuration is shown in  FIG. 3 , discussed below. 
         [0022]    The guide wire grip  22  and the surrounding rigid tube  12  define a toroidal, variable volume guide wire grip inflation chamber  34  therebetween. In  FIG. 1A  the inflation chamber  34  is shown in its minimal volume state, thus allowing the elastomer grip  22  to relax outward toward the inner surface  18  of the rigid tube  12 . This maximizes the diameter of the guide wire passage  24  through the grip  22 , thus allowing the guide wire  32  to be inserted, withdrawn, and/or otherwise manipulated independently of the device  10 . When a fluid (e.g., air or other gas, or liquid) is passed through the inflation port  20  of the tube  12 , the fluid causes the inflation chamber  34  to expand, generally as shown in  FIG. 1B , thereby forcing the guide wire grip  22  radially inward due to the inelasticity of the rigid tube  12 . The inward movement of the guide wire grip  22  results in the guide wire contact surface  30  of the grip  22  contacting the guide wire  32  (if installed). This eliminates any chance of relative movement between the guide wire  32  and surrounding guide wire grip  22 , clamping the guide wire  32  in the guide wire grip  22  and allowing the practitioner to manipulate the guide wire  32  by maneuvering the device  10 , whether by pushing, pulling, or twisting movement. 
         [0023]    In the embodiments of  FIGS. 1A through 3 , the variable volume master inflation chamber  36  comprises two components that concentrically surround the central tube  12  and its guide wire grip  22 . The first end  14  of the rigid tube  12  has an annular end wall  38  that extends outward therefrom. A coaxial cylindrical outer wall  40  extends from the outer edge  42  of the end wall  38  parallel to the central tube  12 . The central tube  12 , end wall  38 , and outer cylindrical wall  40  comprise an annular inflation cylinder  44 . 
         [0024]    A base cylinder  46  is coupled with the inflation cylinder  44 . The base cylinder  46  has an outer surface  48  and mutually opposed first and second ends  50 ,  52  defining a base cylinder length  54 . A coaxial passage  56  extends completely through the length of the base cylinder  46 . The rigid tube  12  of the inflation cylinder  44  telescopes within the base cylinder passage  56 . An annular slot  58  is formed coaxially in the base cylinder  46  between the outer surface  48  and the passage  56 . The slot  58  extends from the first end  50  for the substantial majority of the length  54  of the base cylinder  46  to a depth short of the second end  52  of the base cylinder  46 , i.e., the slot  58  is “blind” and does not extend completely through the entire length  54  of the base cylinder  46 . The outer wall  40  of the inflation cylinder  44  telescopes within the slot  58  of the base cylinder  46 . The rigid tube  12 , end wall  38 , and outer wall  40  of the inflation chamber  44 , and the first end  50  of the base cylinder  44  define the master inflation chamber  36 . 
         [0025]    It will be seen that as the inflation cylinder  44  telescopes relative to the base cylinder  46 , the volume of the master inflation chamber  36  will vary. When the inflation cylinder  44  is pushed toward the base cylinder  46 , as shown in  FIG. 1B , the internal volume of the master inflation chamber  36  is reduced. This causes any working fluid therein (liquid, air or other gas, etc.) to be forced from the master inflation chamber  36  through the inflation port  20  into the guide wire grip inflation chamber  34 . The fluid flowing into the guide wire grip inflation chamber  34  causes the elastomer guide wire grip  22  to distend radially inward to the central axis of the rigid tube  12  due to the rigidity of the tube  12  in which the guide wire grip  22  is installed. This results in the guide wire contact or gripping surface  30  being forced into contact with the guide wire  32 , as shown in  FIG. 1B , thus clamping or gripping the guide wire  32  within the device  10  to allow the guide wire  32  to be maneuvered by manipulating the device  10 . When the inflation cylinder  44  is pulled away from the base cylinder  46 , the volume of the master inflation chamber  36  will expand and the elastomeric nature of the guide wire grip  22  causes the grip to contract against the wall of the rigid tube  12  so that when the inflation cylinder  36  is pulled out far enough, the device reverts to the configuration of  FIG. 1A . 
         [0026]      FIG. 2  shows a modification of the device  10  illustrated in  FIGS. 1A through 1C . The device  110  of  FIG. 2  is configured nearly identically to the device  10  of  FIGS. 1A and 1B  with correspondingly numbered components, the primary exception being the guide wire contact surface of the guide wire grip. In  FIG. 2 , the guide wire grip is designated by the reference numeral  122 , as it differs from the corresponding component  22  of  FIGS. 1A and 1B  by having a different guide wire contact surface ( 130 , in  FIG. 2 , as opposed to the surface  30  of the device  10  of  FIGS. 1A and 1B ). The guide wire contact surface  130  has a high friction coefficient surface, provided by a large number of small protuberances. These protuberances may be formed of the same material as the guide wire grip  122 , i.e., a relatively soft and resilient rubberized or plastic material, or may comprise harder, tooth-like structures projecting inwardly toward the guide wire  32 . (Alternatively, the surface  30  of the device of  FIGS. 1A-1C  may be coated with or comprise a material having a high coefficient of friction.) When the guide wire grip  122  is inflated to grip the guide wire  32 , as described above, the high friction surface  130  provides enhanced grip of the guide wire  32  to further limit or preclude any slippage between the high friction gripping surface  130  and the guide wire  32 . It will also be noted that two inflation ports  20  are provided in the device  110  of  FIG. 2 , an option that may also be provided with the device  10  of  FIGS. 1A through 1C . 
         [0027]      FIG. 3  of the drawings illustrates another slightly different embodiment from the device  10  of  FIGS. 1A and 1B , and the device  110  of  FIG. 2 . The device  210  of  FIG. 3  is configured nearly identically to the devices  10  of  FIGS. 1A and 1B  and  110  of  FIG. 2  with correspondingly numbered components, the exception being the configuration of the guide wire grip. In the device  210  of  FIG. 3 , the guide wire grip  222  does not have a completely cylindrical configuration, but rather has a crescent or C-shaped cross section and subtends only an arcuate portion of the inner surface  18  of the tube  12 . The two opposed edges  60  and  62  limiting the arcuate extent of the grip  222  are shown clearly in the cross-sectional view of  FIG. 3 . Otherwise, the grip  222  extends axially through the tube  12  to a similar extent as the grips  22  and  122  in their respective embodiments. The grip  222  has a first end  226  at the first end  14  of the tube  12  and an opposite second end  228  at the second end  16  of the tube  12 . The configuration of the grip  222  defines an open-sided guide wire passage  224  and semicylindrical guide wire gripping or contact surface  230  within the grip  222 . While the guide wire grip  222  of  FIG. 3  is shown subtending approximately 180° of the inner surface  18  of the tube  12 , it will be seen that the guide wire grip may be configured to extend about a greater or lesser circumferential expanse of the tube  12 , as desired. It will also be noted that this semicircumferential guide wire grip  22  may be incorporated in any of the other embodiments of the device. 
         [0028]      FIG. 4  illustrates an additional embodiment, designated as device  310 . It will be seen that the device  310  of  FIG. 4  is devoid of the base cylinder and most of the inflation cylinder components of other embodiments, generally comprising only the central rigid tube  12  and the internal tubular guide wire grip  22 . The tube  12  and guide wire grip  22  define a guide wire grip inflation chamber  34 , as described above. However, a separate, remotely located fluid pump and reservoir  64  define the master inflation chamber for the device  310  of  FIG. 4 . The pump and reservoir  64  communicate fluidly with the inflation port  20  of the tube  12  by a fluid transfer line  66 . The fluid pump and reservoir  64  are shown only generally in  FIG. 4 , as they may be conventional small devices, as used in the medical and other fields, e.g., aquarium pumps, etc. 
         [0029]    It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims.