Abstract:
A device for gripping a catheter, including a first jaw having a first exterior side and a first radial passage. The device has a second jaw having a second exterior side, opposite the first exterior side, and a second radial passage. The device also has a resilient joint connecting the first and second jaws so that manual compression of the first exterior side toward the second exterior side causes relative rotation between the first and second jaws that mutually aligns the first and second radial passages, such that the catheter can be inserted through the first and second radial passages, and so that releasing the manual compression causes the first and second jaws to rotate so that the first and second radial passages are no longer mutually aligned and so that the catheter passes through and is gripped by the device along mutually aligned first and second central axes.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application 61/935,932, filed Feb. 5, 2014, which is incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates generally to a catheter, and specifically to facilitating rotation and translation of the catheter while the catheter is inserted into a patient. 
       BACKGROUND OF THE INVENTION 
       [0003]    It is advantageous that catheters have as small a diameter as possible, in order to reduce the trauma to a patient into whom the catheter is inserted. Such catheters may be difficult for a physician using the catheter to manipulate. 
         [0004]    Methods for manipulating a catheter, such as the narrow diameter catheter referred to above, are known in the art. For example, U.S. patent application Ser. No. 2005/0096688, to Slazas et al., whose disclosure is incorporated herein by reference, describes a gripper for a catheter shaft which is a flexible tube that surrounds a portion of the shaft. A physician can move the gripper to a selected position on the catheter shaft, and then squeeze the outer surfaces of the gripper, which resiliently collapses around the catheter shaft. When squeezed, an inner surface of the gripper contacts the catheter shaft and can transmit forces applied by the physician to the outside of the gripper, including rotating of the catheter shaft or longitudinal pushing or pulling. 
         [0005]    Documents incorporated by reference in the present patent application are to be considered an integral part of the application except that, to the extent that any terms are defined in these incorporated documents in a manner that conflicts with definitions made explicitly or implicitly in the present specification, only the definitions in the present specification should be considered. 
       SUMMARY OF THE INVENTION 
       [0006]    An embodiment of the present invention provides a device for gripping a catheter, the device including: 
         [0007]    a first jaw having a first grip surface on a first exterior side of the device and containing a first radial passage extending through the first jaw between a first central axis of the first jaw and a first exit point on an outer surface of the device; 
         [0008]    a second jaw having a second grip surface on a second exterior side of the device, opposite to the first exterior side, and containing a second radial passage extending through the second jaw between a second central axis of the second jaw and a second exit point on the outer surface of the device; and 
         [0009]    a resilient joint connecting the first and second jaws so that manual compression of the first exterior side toward the second exterior side causes a relative rotation between the first and second jaws that mutually aligns the first and second radial passages and the first and second exit points, such that the catheter can be inserted through the first and second radial passages to the first and second central axes, and so that releasing the manual compression causes the first and second jaws to rotate so that the first and second radial passages are no longer mutually aligned while the first and second central axes are in mutual alignment, and so that the catheter passes through and is gripped by the device along the mutually aligned first and second central axes. 
         [0010]    Typically, the first jaw includes a first plurality of first jaw leaves, and the second jaw includes a second plurality of second jaw leaves which interleave with the first jaw leaves. 
         [0011]    In a disclosed embodiment the first and second jaws have identical geometric forms. 
         [0012]    In a further disclosed embodiment the first grip surface includes a first set of ridges and indentations, and the second grip surface includes a second set of ridges and indentations. Typically, the first set and the second set align in a region in proximity to the first exit point and the second exit point on release of the manual compression. 
         [0013]    The first jaw, the second jaw, and the resilient joint connecting the jaws may form a catheter grip, the device may further include a cradle which is configured to receive the catheter grip. Typically, the cradle includes a pawl which is configured to engage with the indentations so as to lock the catheter grip in place in the cradle. 
         [0014]    In a yet further disclosed embodiment release of the manual compression causes the device to form an opening having an axis of symmetry corresponding to the mutually aligned first and second central axes, and the opening has a diameter configured to grip the catheter. 
         [0015]    In an alternative embodiment the catheter has a catheter diameter, and release of the manual compression causes the first and second exterior sides to form a curved surface having a diameter at least 15 times greater than the catheter diameter. 
         [0016]    There is further provided, according to an embodiment of the present invention, a method for gripping a catheter, including: 
         [0017]    providing a first jaw having a first grip surface on a first exterior side of the first jaw and containing a first radial passage extending through the first jaw between a first central axis of the first jaw and a first exit point on an outer surface of the first jaw; 
         [0018]    providing a second jaw having a second grip surface on a second exterior side of the second jaw, opposite to the first exterior side, and containing a second radial passage extending through the second jaw between a second central axis of the second jaw and a second exit point on an outer surface of the second jaw; and 
         [0019]    connecting the first and second jaws with a resilient joint so that manual compression of the first exterior side toward the second exterior side causes a relative rotation between the first and second jaws that mutually aligns the first and second radial passages and the first and second exit points, such that the catheter can be inserted through the first and second radial passages to the first and second central axes, and so that releasing the manual compression causes the first and second jaws to rotate so that the first and second radial passages are no longer mutually aligned while the first and second central axes are in mutual alignment, and so that the catheter passes through and is gripped by the first and second jaws along the mutually aligned first and second central axes. 
         [0020]    The present disclosure will be more fully understood from the following detailed description of the embodiments thereof, taken together with the drawings, in which: 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]      FIG. 1  is a schematic exploded view of a catheter device, according to an embodiment of the present invention; 
           [0022]      FIG. 2  is a schematic view of the assembled device in an open state, according to an embodiment of the present invention; 
           [0023]      FIG. 3  is another schematic view of the assembled device in the open state, according to an embodiment of the present invention; 
           [0024]      FIG. 4  is a schematic view of the catheter device in a closed state, according to an embodiment of the present invention; 
           [0025]      FIG. 5  is another schematic view of the catheter device in the closed state, according to an embodiment of the present invention; and 
           [0026]      FIGS. 6A and 6B  are schematic views of the grip in a closed state; according to embodiments of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Overview  
       [0027]    It is advantageous that a catheter that is inserted into a patient during a medical procedure has a diameter that is as small as possible, to reduce trauma to the patient. However, the small diameter of the catheter, together with its length which is typically of the order of 1 meter, determines that the catheter is inherently flexible. While the flexibility may be an advantage, allowing, for example, the catheter to be inserted into a non-linear lumen, the small diameter of the catheter and its relatively long length typically makes the catheter difficult to manipulate. 
         [0028]    Embodiments of the present invention facilitate the manipulation by providing a physician manipulating the catheter with a device that grips the catheter and which has a large mechanical advantage. A disclosed embodiment uses a pair of jaws, typically multi-ridged interleaved jaws, connected by a resilient joint such as a spring, as a catheter grip. Manual compression of the jaws aligns passages in the jaws so that a catheter can be inserted into a central region of the jaws. Releasing the manual compression, so that the spring of the grip returns to a “rest” condition, puts the grip into a relaxed state, herein also termed a grip uncompressed state, which is configured to automatically grasp the catheter. 
         [0029]    An external diameter of the grip is considerably larger than the small diameter of the catheter, providing a mechanical advantage to the physician corresponding to the ratio of the two diameters. Consequently, in the grip relaxed-state virtually no effort is required by a physician in holding the catheter, and the relaxed-state grip may be easily grasped by the physician, enabling the physician to rotate and/or translate the catheter with very little effort. 
         [0030]    In its relaxed-state the grip may be inserted into a free-standing cradle, relieving the physician of the need to hold the grip or the catheter. In its relaxed state the multiple ridges of the interleaved elements may be configured to align, forming ridges and intermediary indentations across the grip. A spring-loaded stopper may be attached to the cradle, so that, in a pawl-like manner, while the grip is in the cradle the stopper is able to engage with the aligned ridges and indentations of the grip. Alternatively, other indentations may be configured in the grip, and the stopper may be configured to engage with these indentations. 
         [0031]    Typically, the free-standing cradle is attached to an adjustable arm, usually an articulated arm, which enables the cradle to be located in any orientation and/or location that is suitable for accepting the grip. The combination of the adjustable arm together with spring-loaded stopper, enables adjustments to made to orientation and location of the grip, and thus to the orientation and location of the catheter. Once the adjustments have been made, the stopper may engage with the indentations referred to above in order to lock the grip and the catheter in place. 
       DETAILED DESCRIPTION 
       [0032]      FIG. 1  is a schematic exploded view of a catheter device  10 ,  FIG. 2  is a schematic view of the assembled device in an open state, and  FIG. 3  is another schematic view of the assembled device in the open state, according to an embodiment of the present invention. Device  10  is configured to grip a catheter, and is also herein termed grip  10 . Grip  10  is comprised of three entities: a pair of ridged jaws  12 ,  14 , and a resilient joint  16 , herein assumed to comprise a spring and also referred to as spring  16 . Jaws  12  and  14  are configured to interleave with each other in the assembled form of the grip, and are sized so that the assembled grip is conveniently grasped between the thumb and fingers of one hand of an operator of the grip. By way of example, ridged jaws  12  and  14  are also substantially similar in form, although this is not a necessity. In some embodiments the two jaws have identical geometric forms. Typically, jaws  12  and  14  are unitary pieces of plastic, which may conveniently made by a plastic forming method such as injection molding. In its assembled state, grip  10  has an approximately circular cross-section. 
         [0033]    For simplicity, the following description of the ridged jaws is written for jaw  12 , and except where otherwise noted the same description applies for jaw  14 . To differentiate corresponding parts of the two jaws the letter A is added to the identifying numeral of jaw  14 . Thus, jaw  12  comprises a holding portion  20 , and jaw  14  comprises a holding portion  20 A. Holding portions  20  and  20 A are also termed exterior sides  20  and  20 A of their respective jaws. Portions  20  and  20 A may be used by an operator of the grip to manually grasp the grip using the fingers and thumb of one hand. 
         [0034]    Exterior side  20  is bounded by a generally arcuate section  24 , and ridges  28  and indentations  30  substantially traverse the complete width of the side. Apart from arcuate section  24 , exterior side  20  is also bounded by a pair of generally linear elements  34 ,  36 . A groove  40 , shaped to accept a corresponding portion  42  of spring  16 , is formed in an outer surface  44  of side  20 . 
         [0035]    Jaw  12  also comprises a leafed portion  50  which is attached to holding portion  20 . Leafed portion  50  comprises a plurality of generally similar leaves  54 , assumed herein by way of example to comprise five leaves  54 , four of which have similar widths, and a fifth, outer, leaf being thicker than the other leaves. Where the leaves are not attached to holding portion  20 , they are each bounded by a generally arcuate section  56 , the arc of section  56  continuing the arc of arcuate section  24 . The leaves are also bounded by two generally linear sections  60 ,  62 . Ridges  28  and indentations  30  are formed in arcuate section  36 . In addition, a passage  70  is formed in each of the leaves, the passage having a width somewhat greater than the diameter of a catheter to be held by grip  10 . Passage  70  is formed in each of leaves  54  as a generally radial element, each passage extending approximately from the equivalent of a center  72  of a circle  73  defined by the arcs of sections  24  and  56 , to the equivalent of an exit point  75  of the circle. At its termination at center  72 , passage  70  is configured as two half-circles  74 ,  76 , separated by a preset distance approximately equal to the width of the passage. Half-circles  74 ,  76  have equal diameters, corresponding to the diameter of a catheter to be grasped by grip  10 . Half-circles  74 A have a common central axis  77 ; half-circles  74  have a common central axis  79 . Axes  77  and  79  are referred to further below. 
         [0036]    Grip  10  is assembled by inserting ridged jaws  12  and  14  so that their leaves  54 ,  54 A interleave, and so that spring portions  42 ,  42 A of spring  16  respectively mate with grooves  40 ,  40 A. 
         [0037]      FIG. 2  and  FIG. 3  schematically illustrate grip  10  after assembly, and when spring  16  has been compressed. The state of the grip in this case, caused by manual compression of the grip, is termed the compressed grip state. The compressed grip state is typically achieved by grasping exterior sides  20  and  20 A with the fingers and thumb of one hand, and squeezing the fingers towards the thumb. Such a motion causes a relative rotation of jaws  12  and  14  about an axis  80  of spring  16 . The rotation rotates linear elements  60 A and  62 A until they respectively meet linear elements  34  and  36 . The rotation also rotates linear elements  60  and  62  until they respectively meet linear elements  34 A and  36 A. 
         [0038]    In the compressed grip state passages  70  and  70 A, and centers  72  and  72 A, align with each other, so that in this state an operator of the grip is able to transfer a catheter to and from centers  72 ,  72 A via passages  70 ,  70 A. However in a region  78  ( FIG. 3 ) corresponding to aligned exit points  75 ,  75 A, in proximity to the circumferential termination of passages  70 ,  70 A, ridges  28  and  28 A, and indentations  30  and  30 A, do not align. 
         [0039]    Grip  10  may transfer from its compressed state to an uncompressed state by the grip operator relaxing his/her hold on portions  20  and  20 A. The operator relaxing his grip causes jaws  12  and  14  to rotate around axis  80  in a direction opposite to the rotation direction to achieve the compressed state. 
         [0040]      FIGS. 4 and 5  are two schematic views of grip  10  in its uncompressed state, according to an embodiment of the present invention. In the uncompressed state passages  70  and  70 A move out of alignment, as do sets of half-circles  74  and sets of half-circles  76 A, and half-circles  74 A and  76 . However the rotation into its uncompressed state aligns the centers of half-circles  74 A and half-circles  74 , so that axes  77  and  79  align, and so that the two sets of half-circles form a cylindrical tube-like opening  82 . If a catheter  90  has been placed within passages  70 ,  70 A of grip  10  in its compressed state, then the catheter moves to opening  82  along aligned axes  77  and  79 , and is grasped there by the grip, when the grip rotates to its uncompressed state. In addition, in contrast to the compressed state, in the uncompressed state ridges  28 ,  28 A and indentations  30 ,  30 A align in region  78 . 
         [0041]    By virtue of the external diameter of grip  10 , it is significantly easier for a physician to rotate and/or translate catheter  90  grasped by grip  10 , as compared to the physician attempting to rotate or translate the catheter by grasping the catheter directly. Typically, an external diameter D ( FIG. 5 ) of a curved surface of grip  10 , corresponding to exterior side  20  of jaw  12  and exterior side  20 A of jaw  14 , is configured to be at least 15 times the diameter of the catheter held by the grip. In some embodiments of the present invention, a number of grips, generally similar to grip  10  but having different external diameters, may be made available to the physician, enabling the physician to select a grip most suitable for manipulating the catheter. In an alternative embodiment, the external diameter of grip  10  may be custom-formed according to the requirement of a specific physician. 
         [0042]      FIG. 6A  is a schematic drawing of grip  10 , in its uncompressed state, as it is held by a physician  100  during a medical procedure, and  FIG. 6B  is a schematic drawing of the grip mounted in a cradle during the procedure, according to embodiments of the present invention. A typical medical procedure where grip  10  may be used comprises an ablation procedure performed by physician  100  on a patient  102 , although other medical procedures where the grip could be used will be apparent to those having ordinary skill in the art. During the procedure physician  100  inserts catheter  90  into the patient, and at any convenient time after an initial insertion the physician may grasp the catheter with grip  10 . The grasping of the catheter by grip  10  is performed by inserting the catheter into passages  70 ,  70 A while the physician compresses the grip to its compressed state, then relaxing the compression of the grip so that the grip returns to its uncompressed state. 
         [0043]    Using grip  10  in its uncompressed state the physician manipulates the catheter into a desired position, as is illustrated in  FIG. 6A . Once in position, the grip, with the grasped catheter may be placed in a cradle  110  as is illustrated in  FIG. 6B . Cradle  110  comprises a generally U-shaped element  112  having an internal diameter approximately equal to the external diameter of grip  10 . Two plane elements  116 ,  118 , approximately semicircular in shape, close off the ends of element  112 . 
         [0044]    Plane elements  116 ,  118  respectively have narrow U-shaped openings  122 ,  124  formed in the elements. U-shaped openings  122 ,  124  are configured to allow catheter  90  to freely move in the openings, so that when grip  10 , with its grasped catheter  90 , is placed in the cradle, there is very little force exerted on the catheter by the cradle. 
         [0045]    Cradle  110  comprises a spring-loaded stopper  130 , which typically has a head  132  having a shape matching the shape of indentations  30  and  30 A. Element  112  comprises an opening allowing head  132  to contact the periphery, i.e., sides  20 ,  20 A, of grip jaws  12 ,  14 . Stopper  130  also has a base  136  and the stopper may typically be operated by the operator pressing on base  136 . A stopper-disengaged state occurs when the operator presses on base  136 , so that head  132  does not engage with ridges  28 ,  28 A or with indentations  30 ,  30 A. A stopper-engaged state occurs when the operator releases the pressure on base  136 , so that head  122  contacts ridges  28 ,  28 A, or engages indentations  30 ,  30 A. If the stopper head engages indentations  30 ,  30 A, then it effectively locks grip  10 , and catheter  90 , in place. Thus, stopper  130  and grip  10  act as a pawl and ratchet combination. 
         [0046]    By way of example the description above of stopper  130  assumes that the stopper is mounted on U-shaped element  112  of cradle  110 . However, it will be understood that stopper  130  may be mounted on any other convenient element of the cradle such as on plane elements  116  or  118 . If the stopper is mounted on an element other than U-shaped element  112 , those having ordinary skill in the art will be able to adapt the above description for the operation of the stopper, mutatis mutandis, to accommodate changes that may be required for the operation. Such changes may include, but are not limited to, incorporating ridges and/or indentations, engadgeable by the stopper, in outer leaves  54  and/or  54 A if the stopper is mounted on elements  116  or  118 . 
         [0047]    Cradle  100  may typically be mounted on an adjustable arm  140  which may be fixed at its base, or which may have its base adjustable, such as by mounting the base on a rail. The cradle mounting is configured so that the cradle may be conveniently fixedly positioned in any location selected by the physician. Once the grip is fixed in position, the physician has his/her hands free for other tasks. 
         [0048]    It will be appreciated that the embodiments described above are cited by way of example, and that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and subcombinations of the various features described hereinabove, as well as variations and modifications thereof which would occur to persons skilled in the art upon reading the foregoing description and which are not disclosed in the prior art.