Abstract:
A system which facilitates the closure of puncture wounds in the vasculature of a patient by helping locate and isolate the site of the puncture wound in the patient. A tube or catheter having an indicator hole for aspirating blood assists in locating the exact site of the wound. A retractor moves the surrounding tissue laterally forming an access path to the wound, and acts as a guide for the wound closure device. The retractor and accessories are preferably used in combination with a surgical clip applicator which delivers clips to the site of the wound, but can also be used with other methods of wound closure such as suturing and stapling.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. application Ser. No. 08/943,369, filed Oct. 3, 1997, now abandoned, which is a continuation-in-part of U.S. application Ser. No. 08/764,611, filed Dec. 5, 1996, now U.S. Pat. No. 6,004,341, which claims the benefit of U.S. Provisional Application Ser. No. 60/009,643 filed Dec. 7, 1995. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a system which assists in the closure of puncture or other wounds in the vasculature of a patient. Specifically, the invention relates to devices which aid in locating and isolating the wound in the vasculature and guiding an appropriate wound closure device to the site, so that the wound may be closed using surgical clips, sutures, or staples. 
     BACKGROUND OF THE INVENTION 
     Transluminal balloon angioplasty is used in the treatment of peripheral vascular disease to increase or restore blood flow through a significantly narrowed artery in a limb; it is also used in the treatment of blockage of the coronary arteries. In fact, coronary angioplasty has emerged as a major viable alternative to bypass surgery for revascularization of stenotic and occluded coronary arteries. Unlike bypass surgery, angioplasty does not require general anesthesia, opening of the chest wall, use of a heart-lung machine, or transfusion of blood. Angioplasty is not only less invasive and less traumatic to the patient, it is also less expensive because of the shorter hospital stay and shorter recovery time. 
     Transluminal balloon angioplasty is performed by first inserting a hollow needle through the skin and into the patient&#39;s femoral artery. A guidewire is advanced through the hollow needle and into the artery, then along the patient&#39;s vasculature toward the site of the blocked blood vessel or heart valve to be treated. X-ray imaging is used to help move the guidewire through the vascular system and into position just past the stenosis to be treated. A balloon catheter is then threaded over the guidewire and advanced until the deflated balloon is within the stenosis. The balloon is then repeatedly inflated to widen the narrowed blood vessel. After the procedure is complete, the catheter and guidewire are withdrawn from the blood vessels and the patient. 
     Angiography, which is used to detect diseases that alter the appearance of blood vessels, is performed in a similar manner. A hollow needle is first inserted through the skin and into the femoral artery, and a guidewire is then inserted through the needle and into the affected blood vessel. A catheter is then threaded over the guidewire and into the blood vessel to be examined, using x-ray imaging to guide the catheter to the desired position. Contrast medium is then injected, and a rapid sequence of x-ray pictures are taken so that blood flow along the affected vessel can be studied. Once complete, the catheter and guidewire are removed from the patient&#39;s body. 
     After the catheter and guidewire used during angioplasty or angiography are removed, the puncture wound in the femoral artery must be closed and the bleeding through the puncture site in the artery stopped. Currently, ice packs and/or pressure are applied to the artery for a period lasting up to several hours in an attempt to stop the bleeding. There exists, however, a significant chance that upon movement by the patient, the wound will reopen and begin bleeding again. Although efforts have been made to close the puncture wound using staples, clips, and sutures, they have been unsuccessful, largely due to the inability to clearly locate and visualize the puncture wound in the femoral artery. 
     Other wounds in the vasculature of a patient can also be difficult to locate and access. Thus, a device and method to facilitate the closure wounds in the vasculature of a patient, such as femoral artery puncture wounds following transluminal balloon angioplasty and angiography, would be extremely beneficial. A device having the ability to aid in locating the puncture wound and facilitating the closure of the wound using staples, clips, or sutures would eliminate the prolonged bleeding currently associated with such wounds. 
     SUMMARY OF THE INVENTION 
     The wound closure system of the present invention aids in locating and isolating a puncture wound in the vasculature of a patient. The system can be used in conjunction with a guidewire which is normally inserted into the vasculature during diagnostic and therapeutic procedures. The devices of the present invention aid the physician in closing the wound, thus eliminating prolonged bleeding associated with these procedures. 
     In accordance with one aspect of the present invention, there is provided a device to facilitate the closure of wounds in the femoral artery. This retractor comprises a body portion separable into two halves, each of the halves having a flat internal surface with a groove, such that when the internal surfaces abut one another, the grooves form a channel through the entire length of the body portion. The retractor has a collar portion at one end, having at least one guide passage which traverses both halves of the body portion, and at least one pin which is insertable into the guide passage. A handle extends laterally from the pin to allow the user to easily manipulate the device. At least one set screw hole can be provided in the collar portion at a right angle to the guide passage, and at least one set screw inserted into the set screw hole to secure the device to the pins. 
     The device can be made of a biocompatible engineering polymer, such as polypropylene, polyethylene, or polyterephthalate. Alternatively, an elastomer or a metal can be used to make the device. 
     A hollow dilator adapted to receive a guidewire is preferably used in conjunction with the retractor. The dilator is inserted through the channel in the body portion of the retractor, and extends past the distal end of the reactor. The dilator preferably includes at least one indicator hole located at the distal end, which extends past the end of the retractor. The dilator has a double-sleeved inflatable balloon mounted on its distal end just proximal to the indicator hole, and a second inflatable balloon mounted just distal to the indicator hole. These balloons help anchor the dilator in place, and provide access to the puncture wound from the surface of the patient&#39;s body. A guidewire is used to help guide the insertion of the dilator. The guidewire is inserted through the hollow dilator, and the dilator advanced over the guidewire into its proper position. 
     Another aspect of the present invention includes a system for facilitating the closure of wounds in the vasculature of a patient. The system includes a retractor as described above, a hollow dilator adapted to receive a guidewire, and a guidewire. The guidewire is inserted through the dilator, and the dilator is inserted through the channel in the retractor. Preferably, a guide assembly adapted to be reversibly attached to a surgical clip applicator is used. The guide assembly receives the guidewire to help guide the clip applicator to the site of the puncture wound. 
     The dilator preferably has a source of negative pressure connected to its proximal end in fluid communication with the hollow dilator. The source of negative pressure can be a syringe or any other appropriate source. 
     A method for facilitating the closure of a wound in the vasculature of a patient is also described. A guidewire is first inserted into the patient&#39;s vasculature through the wound, until the distal end of the guidewire is within the vasculature and the proximal end remains outside the patient&#39;s body. The proximal end of the guidewire is inserted into the distal end of a hollow dilator having a double-sleeved balloon and a second balloon distal the double-sleeved balloon mounted on it. The dilator is advanced over the guidewire until it reaches the wound. The balloons are inflated to anchor the dilator in position, and the proximal end of the dilator is inserted into the distal end of a retractor. The retractor is advanced between the two sleeves of the double-sleeved balloon. The two halves of the retractor are separated and the dilator and the inner sleeve of the double-sleeved balloon are removed from the patient. Using the retractor and the outer sleeve of the balloon as a guide, the wound is accessed and closed by means such as clipping, stapling, or suturing. 
     Preferably, a source of negative pressure is provided on the proximal end of the dilator during insertion, until blood is drawn into the dilator from the vasculature. This assists the user in determining when the dilator is properly positioned. 
     A hollow indicator tube mounted on a surgical clip applicator is preferably used to close the wound. The applicator is advanced over the guidewire and through the channel in the retractor until the applicator contacts the wound. To aid proper insertion, a source of negative pressure is provided at the proximal end of the indicator tube, until blood is drawn into the indicator tube from the vasculature. 
     In yet another embodiment of the retractor used to facilitate wound closure, the retractor has a body portion and a handle portion. At its distal end, the body portion has a retracting portion having two movable halves which extend away from the body portion. The halves are formed such that when the internal surfaces abut one another, a channel is formed which extends completely through the retracting portion. The handle portion connects to the body portion and controls the movement of the two moveable halves. Preferably, the handle portion comprises two handles, and a loop extending from one handle to the other. This loop surrounds a screw mounted on the other handle. This locking mechanism acts to secure the position of the handles and the retracting portion of the retractor. 
     A hollow catheter having an open proximal end and an open distal end, adapted to receive a guidewire therethrough, is used in conjunction with the retractor. The hollow catheter is inserted through the channel in the retracting portion of the retractor. The catheter is preferably a dual-lumen catheter, having an inner lumen adapted to receive a guidewire, and an outer lumen which surrounds the inner lumen. The outer lumen has at least one indicator hole located in an outer wall to allow for the aspiration of blood through the outer lumen. This helps position the catheter properly within the patient&#39;s body. 
     The retractor and dual-lumen catheter are used in the following manner. The retractor is mounted on the outside of the distal end of the catheter, approximately 0.5 mm behind the indicator hole located in the outside wall of the catheter. The proximal end of a guidewire which is already in place in the patient as a result of a diagnostic or therapeutic procedure, is inserted into the distal end of the inner lumen of the dual-lumen catheter, and the catheter and retractor are advanced as a single unit over the guidewire. 
     Preferably, a source of negative pressure is provided at the proximal end of the outer lumen of the dual-lumen catheter during its advancement. As soon as blood is drawn into the outer lumen through the indicator hole, advancement of the catheter and retractor are stopped. The two halves of the retracting portion are then separated to expose the wound, the catheter and guidewire are removed, and the wound is closed. 
     Further, a second catheter having an inflatable balloon on its distal end may be used. Once the retractor and double-lumen catheter are in place, the guidewire is removed from the patient through the inner lumen of the dual-lumen catheter. The inner catheter having an inflatable balloon mounted on its distal end is inserted through the inner lumen of the dual-lumen catheter and into the patient. Once inside the vasculature, the balloon is inflated and drawn in a proximal direction until resistance is felt. This helps to anchor the catheter in place as well as stop the bleeding during the closing of the wound. The dual-lumen catheter is removed, and the inner catheter is used to guide a closing device to the wound. The wound is closed as the balloon is deflated and the inner catheter is removed. Finally, the retractor is removed. 
     The present invention advantageously provides a simple and safe method of facilitating the closure of a wound in the vasculature of a patient, and the devices which facilitate this method. A retractor, used in conjunction with a guidewire, dilator or catheter, helps locate and isolate the site of the puncture wound in the patient. The retractor moves the surrounding tissue laterally as it is advanced into the patient, and acts as a guide for the physician in locating the exact site of the wound. The retractor is preferably used in combination with a surgical clip applicator which delivers clips to the site of the wound, but can also be used with other methods of wound closure such as suturing and stapling. The present invention eliminates the prolonged bleeding associated with current cardiac diagnostic and therapeutic procedures, and provides a significant advancement in the medical field. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of a portion of a human body, showing the site where the femoral artery is typically accessed and punctured during angioplasty or angiography. 
     FIG. 2 is a perspective view of one embodiment of the wound closure device of the present invention. 
     FIG. 3 is an exploded perspective view of the wound closure device of the present invention. 
     FIG. 4 is a cross-sectional view of a portion of a human body, showing the femoral artery accessed via a hollow needle, and a guidewire having an inflatable balloon attached, inserted through the hollow needle and into the femoral artery. 
     FIG. 5 is a side view of the distal end of a surgical clip applicator to be used in conjunction with the wound closure device of the present invention. 
     FIG. 6 is a partial cross-sectional view of a portion of a human body, showing the femoral artery having a guidewire positioned therein, and a perspective view of the retractor of the present invention positioned over the guidewire, with its distal tip at the site of the puncture in the femoral artery. 
     FIG. 7 is a side view of the retractor with its cap removed and the wings of the surgical clip applicator inserted into the grooves within the retractor. 
     FIG. 8 is a cross-sectional view of the clip applicator and retractor taken along line  8 — 8  in FIG.  7 . 
     FIG. 9 is a perspective view of an alternate embodiment of a femoral artery closure device in accordance with the present invention. 
     FIG. 10 is an exploded perspective view of the alternate embodiment of the femoral artery closure device illustrated in FIG.  9 . 
     FIG. 11 is a side view of the 2 halves of the retractor of FIGS. 9 and 10 separated slightly and having a dilator inserted therethrough. 
     FIG. 12 is a cross-sectional view of the distal end of the retractor having a dilator and a guidewire inserted therethrough. 
     FIG. 13 is a side view of the components of the femoral artery localization and closure assembly. 
     FIG. 14 is a side view of the 2 halves of the retractor separated slightly and having a surgical clip applicator with an applicator guide and a guidewire inserted therethrough. 
     FIG. 15 is a top view of the surgical clip applicator guide of the present invention. 
     FIG. 16 is a side view of the clip applicator guide, having a guidewire inserted therethrough. 
     FIG. 17 is an enlarged perspective view of a dilator having a removable double-sleeved balloon at its distal end. 
     FIG. 18 is an enlarged perspective view of the dilator of FIG. 17 with the sleeves of the balloon inflated. 
     FIG. 19 is an enlarged perspective view of the dilator of FIG. 18 having the retractor inserted between the sleeves of the balloon. 
     FIG. 20 is an enlarged perspective view of the dilator and retractor of FIG. 19 with the dilator removed, illustrating the tunnel formed by the retractor and the outer sleeve of the balloon. 
     FIG. 21 is a perspective view of another alternate embodiment of a retractor in accordance with the present invention. 
     FIG. 22 is an exploded perspective view of the alternate embodiment of the retractor illustrated in FIG.  21 . 
     FIG. 23 is a perspective view of an alternate embodiment of a dilator having a double-sleeved balloon and a distal balloon mounted thereon in accordance with the present invention. 
     FIG. 24 is a top view of another embodiment of the double-sleeved balloon, illustrating the I-shaped inner sleeve. 
     FIG. 25 is a perspective view of the alternate embodiment of the dilator of FIG. 23, showing the balloons inflated. 
     FIG. 26 is a cross-sectional view of the dilator of the present invention, illustrating the various lumens in the dilator. 
     FIG. 27 is a side view of the distal end of a surgical clip applicator with an indicator tube mounted thereon. 
     FIG. 28 is a perspective view of an alternate embodiment of a retractor of the present invention, shown in a closed position. 
     FIG. 29 is a perspective view of an alternate embodiment of a retractor of the present invention, shown in an open position. 
     FIG. 30 is a side view of a dual-lumen indicator tube of the present invention, having a guidewire inserted through its central lumen. 
     FIG. 31 is a side view of the dual-lumen indicator tube of the present invention, with the retractor mounted thereon. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Introduction 
     Although the description which follows details the closure of a puncture wound in a femoral artery, the present invention is not intended to be limited to use only with the femoral artery. Rather, the description which follows is exemplary only, and those of skill in the art can readily modify the method described below to use with other types of wounds to the vascular system. 
     Referring first to FIG. 1, there is shown a side view of a portion of a human body, showing a site  5  where a femoral artery  10  is typically accessed and punctured during angioplasty or angiography. During these procedures, a hollow needle  15  is first inserted through the skin and into the femoral artery  10 . A guidewire  20  is then inserted through the proximal end of the hollow needle  15  and into the artery  10 , as illustrated in FIG. 4, and the needle  15  is withdrawn from the patient. The guidewire  20  is advanced through the patient&#39;s vasculature, often using x-ray imaging as an aid in directing the guidewire  20  to the desired location. 
     Once the guidewire  20  is in the desired location, a catheter is used. The proximal end of the guidewire  21  is inserted into the distal end of the catheter, and the catheter is threaded over the guidewire  20  and advanced to the desired location. In the case of angioplasty, the catheter has an inflatable balloon attached at its distal end. Once in position within the stenosis, the balloon is repeatedly inflated and deflated to widen the narrowed blood vessel. In the case of angiography, a catheter is threaded over the guidewire  20  as just described and into the blood vessel to be examined. Contrast medium is then injected, and a rapid sequence of x-ray pictures are taken so that blood flow along the affected vessel can be studied. 
     After either of these procedures is completed, the catheter and guidewire  20  are withdrawn from the blood vessel and the patient. The puncture wound  25  in the femoral artery  10  caused by the insertion of the hollow needle  15 , guidewire  20  and catheter must be closed and the bleeding through the puncture site  25  in the artery  10  stopped. 
     Construction of the Retractor 
     In order to facilitate the closure of the wound  25  in the femoral artery  10 , a retractor  30  is employed. The retractor  30 , illustrated in FIGS. 2 and 3, comprises a body portion  35  and a cap  40 . The body  35  of the retractor  30  has a narrow, tapered distal end  37 , and a broader circular proximal end  41 . The device  30  has two handles  43 ,  45  located on its body  35 , one on each half  35   a ,  35   b . The handles  43 ,  45  are positioned approximately one-third of the way from the proximal end of the retractor  41 , and extend laterally from the body of the retractor  35 . These handles  43 ,  45  assist the user in handling the device  30 . The retractor  30  also comprises a circular cap  40  at its proximal end  41 , having a hole  47  therethrough. This hole  47  extends into a channel  50  which runs the entire length of the device  30 . 
     As illustrated in FIG. 3, the cap  40  and body  35  of the retractor  30  comprise three separable pieces: the cap portion  40  and the two halves of the body portion  35   a ,  35   b . The removable cap  40  is internally threaded  55 . The proximal end  39  of the two halves of the body  35   a ,  35   b  are externally threaded  60 , and are adapted to removably receive the cap  40 . Each half of the body of the retractor  35   a ,  35   b  has a semi-circular groove  65  on its flat internal surface  67 . When the cap  40  is securely screwed onto the two halves of the body  35   a ,  35   b  as illustrated in FIG. 2, the three pieces are joined together, and the semi-circular grooves  65  form a channel  50  running through the interior of the device  30 , which starts at the hole in the cap  47  at the proximal end  41  and continues through the body  35 , ending at a small hole  49  in the distal end of the retractor  37  where the two halves of the body  35   a ,  35   b  come together. When the cap  40  is unscrewed from the body  35 , the two halves of the body  35   a ,  35   b  may be moved apart from one another, as illustrated in FIG.  3 . 
     Alternate Embodiment of the Retractor 
     Another preferred embodiment of the invention is illustrated in FIGS. 9-10. In this embodiment, the retractor  100  includes a retraction mechanism whereby the two halves  102   a ,  102   b  of the retractor body  102  can be moved apart from one another a desired distance, while maintaining their alignment. The retractor again comprises a body portion  102 , and an annular cap  104 . The two halves  102   a ,  102   b  of the body are initially held together by the internally threaded  105  cap  104 . This cap  104  is screwed on and off the externally threaded halves  102   a ,  102   b  of the retractor body. The outer surface of the cap  106  can be textured to ease hand tightening and loosening of the cap  106 . As illustrated in FIG. 10, each half  102   a ,  102   b  of the retractor body again has a semicircular groove  126  running longitudinally down the center of its flat internal surface  128 . When the cap  104  is securely screwed onto the two halves  102   a ,  102   b  of the retractor body, such that the internal surfaces  128  abut one another, the semicircular grooves  126  form a channel  108 . The cap  104  is open on both ends and through its center to permit access to the channel  108 . 
     The retractor  100 , as illustrated in FIGS. 9-10, further comprises a collar  110  located on the retractor body  102  just distal to the externally threaded proximal end  103 ; a pin assembly  116 , comprising two parallel pins  116   a ,  116   b  attached at one end to a perpendicular handle  116   c ; and two set screws  120   a ,  120   b . As illustrated in FIG. 10, the pins  116   a ,  116   b  traverse guide passages  118   a ,  118   b  bored through the collar region  110   b  of one half  102   b  of the retractor body and are insertable within holes  124   a ,  124   b  in the collar region  110   a  of the other half  102   a  of the retractor body, such that one half  102   b  of the retractor body can slide apart from the other half  102   a  on the pins  116   a ,  116   b . The collar  110   b  includes internally threaded holes  122   a ,  122   b  adapted to receive externally threaded set screws  120   a ,  120   b . The set screw holes  122   a ,  122   b  enter the collar region  110   a  at right angles to the pin guide passages  118   a ,  118   b , such that when the set screws  120   a ,  120   b  are advanced, they tighten upon the pins  116   a ,  116   b  and thus, fix the distance between the two halves  102   a ,  102   b  of the retractor body. 
     Second Alternate Embodiment of the Retractor 
     Yet another embodiment of the retractor of the present invention is illustrated in FIGS. 21 and 22. The retractor  200  comprises a body portion  202  having a distal end  204 , and a broader, collar portion  206  at its proximal end  205 . Like the embodiment described above, this retractor  200  is formed in two halves  202   a ,  202   b  and preferably has a tapered distal end  204 . Each half of the body of the retractor  202   a ,  202   b , has a semi-circular groove  208  on its flat internal surface  209 . When the two halves  202   a ,  202   b  are joined together, the semi-circular grooves  208  form a channel  210  running through the interior of the device  200 , extending from the proximal end  205  to the distal end  204 . 
     The collar  206  of the device  200  includes a pin assembly  212  comprising two parallel pins  212   a ,  212   b  attached at one end to a handle  212   c , and two set screws  214   a ,  214   b . As illustrated in FIG. 22, the pins  212   a ,  212   b  traverse guide passages  216   a ,  216   b  bored through the collar region  206  of one half of the retractor body  202   b , and are insertable within holes  218   a ,  218   b  in the collar region  206  of the other half of the retractor body  202   a , such that one half of the retractor body  202   b  can slide apart from the other half  202   a  on the pins  212   a ,  212   b . The collar  206  also includes internally threaded holes  220   a ,  220   b  adapted to receive externally threaded set screws  214   a ,  214   b . The set screw holes  220   a ,  220   b  enter the collar region  206  at right angles to the pin guide passages  216   a ,  216   b  such that when the set screws  214   a ,  214   b  are advanced, they tighten upon the pins  212   a ,  212   b  and thus, fix the distance between the two halves of the retractor body  202   a ,  202   b.    
     Third Alternate Embodiment of the Retractor 
     Still another embodiment of the retractor of the present invention is illustrated in FIGS. 28 and 29. The retractor  300  comprises a distal body portion  302 , and a proximal handle portion  304 . The distal body portion  302  of the retractor  300  is formed in two portions or halves  302   a ,  302   b . At the distal end  306  of the body portion  302 , a retracting portion  308  extends away from, and at an angle to the body portion  302 . Preferably, the retracting portion  308  extends substantially perpendicular to the body portion  302 . The retracting portion  308  is also formed in two separable portions or halves  308   a ,  308   b . Each of these portions  308   a ,  308   b  can be semi-circular in shape, or have a semi-circular groove  312  in its flat, internal surface (FIG.  29 ). The external surfaces are preferably rounded, and tapered toward the distal end  310 . When the two portions  308   a ,  308   b  are brought together such that the two portions abut one another, as seen in FIG. 28, a channel  314  is formed through the interior of the retracting portion  308  of the retractor  300 . 
     Handles  316   a ,  316   b  are located at the proximal end  304  of the retractor  300 . The handles  316   a ,  316   b  are preferably elongate and of a dimension sufficient to permit manipulation by hand. The handles  316   a ,  316   b  are securely connected to the body portion  302  of the retractor  300 . The handles  316   a ,  316   b  are used to control the movement of the retracting portion  308  of the retractor  300 . 
     FIGS. 28 and 29 also illustrate a loop  320  extending from one of the handles  316   a  in the direction of the other handle  316   b . The other handle  316   b  has a screw  322  inserted therethrough. The loop  320  surrounds the screw  322 , such that when the screw  322  is tightened, the loop  320  is held securely between the screw  322  and the underlying surface. This mechanism acts to control the distance between the handles  316   a ,  316   b  thereby controlling the distance between the two halves of the retracting portion  308   a ,  308   b . The handles  316   a ,  316   b , and the corresponding retracting portions  308   a ,  308   b  may be locked into any position by sliding the loop  320  along the screw  322 , then tightening the screw  322  to securely fix the loop  320  in the desired position. Of course, other locking mechanisms well known to those of skill in the art may also be used to control the positioning of the retractor  300 . 
     The retractors of the present invention are preferably formed of one of many strong, biocompatible engineering polymers. Plastics such as polypropylene, polyethylene, or polyterephthalate, are preferred. Elastomers such as silastics or silicones can also be used. Most preferably, metals such stainless or surgical steel, or titanium, are used to form the retractor. 
     Construction of the Dilator 
     As illustrated in FIGS. 11-13, the retractor  100  is preferably used in conjunction with a dilator  150 . As is known to those of ordinary skill in the art, the hollow dilator  150  preferably includes a standard male connector  149 , such as a Luer connector, at its proximal end and is narrowly tapered at its distal end  151 . The inside diameter of the dilator channel  160  is large enough to accommodate a guidewire  144 , so that the dilator  150  can be fed along the guidewire  144  and into the lumen of the femoral artery. Dilators are commonly used in procedures such as angioplasty and angiography to enlarge the puncture site and provide improved access to the femoral artery. 
     In one embodiment of the present invention, the dilator is preferably notched  152  near its distal end  151  around its entire circumference. This notch  152  provides a seat for the tapered distal tips of the two halves  102   a ,  102   b  of the retractor body, such that when the retractor  100  is closed upon the dilator  150 , the sharp distal tip of the retractor body  112  is buried in the notch  152  of the dilator. This forms a smooth transition between the dilator  150  and retractor  100  (FIG.  12 ). As will be explained more fully below, when the guidewire  144  is inserted through the dilator  150  and the dilator  150  is then inserted through the retractor  100 , (FIGS.  12 - 13 ), the dilator  150  lies securely within the interior circular channel  108  (FIG. 9) running the length of the retractor body  102 . 
     The dilator  150  also preferably includes at least one indicator hole  154 . The dilator  150  illustrated in FIGS. 11-13 includes two indicator holes  154  directly opposed to one another, located a few millimeters distal to the notch  152 ; the distance X between the holes  154  and the notch  152  is preferably only slightly larger than the thickness of the wall of the femoral artery. 
     Alternatively, a transducer-tipped pressure monitoring catheter, mounted to the outside of the dilator  150 , may be used in conjunction with the dilator  150  and indicator holes  154 . Use of the indicator holes  154  and pressure sensor will be described in detail below. 
     Dilator/Retractor Assembly 
     Another embodiment of the present invention comprises an entire femoral artery localization and closure assembly illustrated in FIG.  13 . The guidewire  144  which emerges from the original puncture wound is fed through the dilator  150 , and then the dilator  150  is inserted through the retractor  100 . The retractor  100  is advanced along the dilator  150  until the distal tips of the retractor  112  stop within the notch  152  in the dilator  150 . Preferably, the male fitting  149  on the proximal end of the dilator  150  is connected to one port of a commercially available 3-way Y-connector  156 . A syringe  158  or other means of applying negative pressure is connected to one of the other ports on the Y-connector  156  and the proximal end of the guidewire  144  exits the Y-connector  156  via the remaining port. The Y-connector  156  therefore acts as a seal at the proximal ends of dilator  150  and guidewire  144 . 
     Alternate Embodiments of the Dilator 
     In another embodiment of the invention, a modified dilator  150  is used. As illustrated in FIG. 17, a double-sleeved balloon  170  is removably attached to the dilator  150  near its distal end  151 , proximal to a single indicator hole  154 . Preferably, the balloon  170  is placed a distance from the indicator hole  154  which is approximately the width of the arterial wall, e.g., about 1.5 mm. The inflatable, double-sleeved balloon  170  is angled at its distal end  172  to allow the balloon to better fit the femoral artery  10 . The balloon  170  includes inflation means which allow the balloon to be inflated and deflated from the proximal end of the dilator  150 . Use of the double-sleeved balloon  170  will be described in detail below. 
     In yet another embodiment, illustrated in FIGS. 23-25, the dilator  220  has both a double-sleeved balloon  222  and a second inflatable balloon  224  mounted on its distal end  226 . The double-sleeved balloon  222  is removably attached to the dilator  220  near its distal end  226 , proximal to the single indicator hole  228 . The second inflatable balloon  224  is mounted on the dilator  220  just distal to the indicator hole  228 . When inflated, this second balloon  224  helps anchor the dilator  220  in place in the femoral artery  10 , preventing the dilator  220  from being pulled out of the artery  10  during the procedure. Thus, the distal, second balloon  224  is positioned together with the indicator hole  228 , within the artery  10 , while the double-sleeved balloon  222 , proximal to the indicator hole  228 , remains outside of the artery  10  as illustrated in FIG.  25 . The balloons  222 ,  224  assist in the proper positioning of the dilator  220 , and help anchor the dilator  220  once it is properly positioned, as will be explained in detail below. 
     The inner sleeve  230  of the double-sleeved balloon  222  is preferably shaped to facilitate the insertion of the retractor  200  between the two sleeves  229 ,  230 , as will be described in more detail below. As illustrated in FIG. 24, the inner sleeve  230  can be in the shape of an “I”, thus providing additional space between the inner surface of the outer sleeve  229 , and the outer surface of the inner sleeve  230 . This allows the two halves of the retractor body  202   a ,  202   b  to be inserted between the two sleeves  229 ,  230  more easily. The two sleeves of the balloon  229 , 230  can be shaped in any form that would help facilitate insertion of the retractor  220 . 
     The dilator  200  having both a double-sleeved balloon  222  and a second, distal balloon  224 , is further illustrated in FIG.  26 . As can be seen from the drawing, the dilator  200  has  4  different lumens  232 ,  234 ,  236 ,  238  extending from the proximal end of the dilator  225  to the distal end of the dilator  226 . A guidewire  240  is inserted through one of the lumens  236 . Another lumen  232  is used to inflate the double-sleeved balloon  222 , while a third lumen  238  is used to inflate the second balloon  224  at the distal end of the dilator  226 . The fourth lumen  234  is used to aspirate blood through the indicator hole  228  at the distal end of the dilator  226 . Syringes are preferably used to provide the aspiration and inflation pressure through these lumens  232 ,  234 ,  236 ,  238 . The proximal end of the dilator  225  is preferably adapted to allow for fluid communication between the syringes and the various lumens  232 ,  234 ,  236 ,  238  in the dilator. Of course, other means of aspirating blood and inflating the balloons may also be used, and connectors specifically adapted for these devices can be attached at the proximal end of the dilator  225  to accommodate the means chosen. 
     Dual Lumen Catheter 
     In yet another embodiment of the invention, a dual-lumen catheter is used to locate the exact site of the puncture wound. As illustrated in FIGS. 30 and 31, the catheter  340  has an inner lumen  342  which extends from the proximal end of the catheter  344  all the way to the distal end of the catheter  346 . This inner lumen  342  is adapted to receive an inner catheter  360  or guidewire  350 , as will be explained in more detail below. 
     The outer lumen of the dual-lumen catheter  340  surrounds the inner lumen  342 , and also extends from the proximal end of the catheter  344  to the distal end  346 . Near the distal end of the catheter  346 , at least one indicator hole  352  is positioned in the outer wall of the catheter  340 . The indicator hole  352  provides fluid communication between the area outside of the catheter  340  and the outer lumen. The outer surface of the catheter  354  surrounding the indicator hole  352  is preferably raised, acting as a stop. Preferably, the distance between the indicator hole  352  and the proximal end of the raised surface of the retractor  354 , is approximately the same as the thickness of the wall of the femoral artery. As will be explained below, the retractor  300  is first mounted on the distal end of the catheter, and positioned such that the distal tip of the retracting portion  310  stops just proximal to the raised surface  354 , about 0.5 mm proximal to the indicator hole  352 . This assures that the distal tip of the retracting portion  310  will be properly positioned inside the patient&#39;s body at the site of the wound in the artery. 
     At the proximal end of the catheter  344 , the proximal end  358  of the outer lumen is preferably joined to a connector  364 , such as a Luer-type connector, which is adapted to receive a syringe  360  or other source of negative pressure, as will be explained in more detail below. 
     The Surgical Clip Applicator 
     The retractor of the present invention is used to facilitate closure of wounds to the vasculature of a patient using surgical clips, staples, or sutures. One aspect of the present invention therefore includes the use of a surgical clip applicator  70 . A surgical clip applicator  70  for use with the retractor  30  of the present invention is illustrated in FIG.  5 . As shown in this figure, the distal end of the clip applicator  75  is fitted with two triangular protrusions or wings  77   a ,  77   b  that extend laterally from the sides of the distal end of the clip applicator  75 . These wings  77   a ,  77   b  are configured to fit within the grooves  65  located on the interior surface of the two halves  35   a ,  35   b  of the body of the retractor  30 , as is best seen in FIG.  8 . With the wings  77   a ,  77   b  of the clip applicator  70  in the grooves  65  in the two halves of the body of the retractor  35   a ,  35   b , the clip applicator  70  is guided into proper position within the patient&#39;s body, as will be discussed in more detail below. In addition, the surgical clip applicator  70  preferably has a guide  80  attached to its distal end  75 . The guide  80  preferably extends laterally from the side of the clip applicator  70 , and is open at its proximal and distal ends such that a guidewire  20  may be threaded therethrough. This guide  80  is used in combination with the guidewire  20  to accurately guide the clip applicator  70  to the site of the vascular puncture  25 , as will be described below. 
     The surgical clip applicator  70  preferably also has a stop  85  located proximal of the distal end  75 , at the point where the proximal ends of the wings of the applicator  77   a ,  77   b  end. As will be explained, the stop  80  also aids in the proper positioning of the clip applicator  70  at the site of the vascular puncture  25 , and prevents the clip applicator  70  from being inserted too far into the patient&#39;s body. 
     Alternate Surgical Clip Applicator Assembly 
     Referring now to FIGS. 14-16, there is illustrated an alternate embodiment of a surgical clip applicator assembly  130 . The clip applicator assembly  130  incorporates a standard commercially available surgical clip applicator  132 . In accordance with the present invention, the applicator is modified to include a guide assembly  134  reversibly fastened near its distal end. The guide assembly comprises a winged guide plate  138  which is reversibly secured to a body  140 . In the embodiment illustrated in FIGS. 14-16, allen screws  142  are used to attach the guide plate  138  but other well known means of attachment can also be used. The distal end of the surgical clip applicator  132  slides within the channel  148  (FIG. 15) formed when the winged guide plate  138  is fastened to the guide body  140 . 
     Attached to the guide body  140  is a guidetube  136  which is adapted to accept the guidewire  144 . A preferred embodiment of said guidetube  136  includes a mechanism to close the guidetube  136  once the guidewire  144  has entered. Such a mechanism may involve a second partially open tube which fits within said guidetube  136 . This second tube can be rotated within the guidetube  136  to open the guidetube  136  when the openings in both tubes are aligned or close the guidetube  136  when the openings of the tubes are offset. To facilitate the opening and closing, the inner tube preferably includes a handle that passes through a slot in the outer guidetube  136 . This mechanism can be spring-loaded like the closures commonly used on pieces of jewelry. 
     The surgical clip applicator guide assembly  134 , together with the retractor  100  and the guidewire  144 , is designed to accurately guide the clip applicator  132  to the site of the femoral artery puncture as detailed below. As explained above, the lateral edges of the winged guide plate  138  are configured to fit within the groove  126  (FIG. 10) located on the interior surface of each half of the retractor body  102   a ,  102   b . The surgical clip applicator  132  is guided between the retracted halves of the retractor body  102   a ,  102   b  following the guidewire  144  which passes through the guidetube  136  at the distal most end of the surgical clip applicator  132 . 
     Second Alternate Surgical Clip Applicator Assembly 
     An alternate embodiment of the surgical clip applicator assembly  250  is illustrated in FIG.  27 . Again, the clip applicator assembly  250  incorporates a standard commercially available surgical clip applicator  252 . The applicator  252  is modified to include a guide assembly  254  reversibly fastened near its distal end  256 . The guide assembly  254  is adapted to receive an indicator tube  260 . The indicator tube  260  is a hollow tube having an indicator hole  264  near its distal end  262 . The indicator tube  260  is adapted to receive a guidewire  240  therethrough, and to be connected to a source of negative pressure at its proximal end. This source of negative pressure, such as a syringe, is used to provide aspiration through the indicator hole  264 . When properly positioned on the clip applicator  252 , the distal end of the indicator tube  262  and the indicator hole  264  extend past the distal end of the clip applicator  256 . Preferably, the distance between the indicator hole  264  and the distal tip of the clip applicator  256  is approximately equal to the width of the arterial wall, e.g., about 1.5 mm. 
     Methods of Use 
     Referring first to FIGS. 4-8, a first method of use of the retractor  30  in conjunction with a surgical clip applicator  70  to close a wound  25  in the femoral artery  10  will now be described. As noted above, during angioplasty or angiography, the femoral artery  10  is first punctured with a hollow needle  15  and a guidewire  20  is inserted therethrough (FIG.  4 ). A proximal portion of the guidewire  21  remains outside the patient&#39;s body. After the distal end of the guidewire  23  is in position within the femoral artery  10 , the hollow needle  15  is removed. A catheter (not shown) is then threaded over the guidewire  20 , and inserted into the patient&#39;s body. 
     In a preferred embodiment, a specially designed guidewire  20  having an inflatable balloon  24  located near its distal end  23  is used for the diagnostic or therapeutic procedure. The guidewire  20  is threaded through the hollow needle  15  and into the patient&#39;s vasculature. Alternatively, such as for balloon angioplasty procedures, a standard guidewire well known to those of skill in the art can be used in conjunction with a balloon catheter. The balloon on the distal end of the catheter can be used in place of the balloon  24  located on the guidewire  20 . 
     Following completion of the therapeutic or diagnostic procedure, the catheter used during the procedure is removed. The guidewire  20  remains in place in the patient&#39;s vasculature. (Note that when a balloon catheter is used in place of a guidewire having a balloon on its distal end, the catheter is left inside the patient, and use of its balloon is identical to the use of the balloon  24  on the guidewire  20  described below). 
     When the physician desires to close the wound  25  in the femoral artery  10 , he or she first withdraws the guidewire  20  and/or catheter through the patient&#39;s vasculature using the portion of the guidewire  20  and/or catheter that remains outside the patient&#39;s body  21 , until the distal end  23  of the guidewire  20  and/or catheter is within the femoral artery  10  close to the femoral artery puncture site  25 . The balloon  24  on the distal end  23  of the guidewire  20  or catheter is then inflated, and the guidewire  20  or catheter is withdrawn further until the physician feels some resistance. This will indicate that the balloon  24  is inside the femoral artery  10  and at the site of the puncture wound  25 . The physician then threads the proximal end of the guidewire  21  into the hole  49  located at the distal end  37  of the fully assembled retractor  30  (FIGS. 2,  3  and  6 ). The guidewire  20  is threaded through the channel  50  formed in the body of the retractor  35 , until the proximal end of the guidewire  21  emerges through the hole  47  in the cap  40  at the proximal end of the retractor  41  (FIG.  6 ). The retractor  30  is then slowly advanced along the guidewire  20  and into the patient&#39;s body, until resistance is felt. This resistance indicates that the distal tip of the retractor  37  is contacting the inflated balloon  24  in the femoral artery  10 . The distal tip of the retractor  37  therefore will be properly located at the site of the puncture in the femoral artery  25 , as is shown in FIG.  6 . 
     In a preferred embodiment, the guidewire  20  used in conjunction with the femoral artery closure retractor  30  has a marking  27  on it which also helps to indicate when the retractor  30  has been properly positioned (FIG.  6 ). This marking  27  preferably consists of a tiny bead or colored line on the guidewire  20 . The marking on the guidewire  27  is placed proximal of the proximal end of the balloon  26 . The length of the retractor  30  is measured, and the marking  27  is made at least that same length in a proximal direction on the guidewire  20 , measured from the proximal end of the balloon  26 . Thus, when the retractor  30  is advanced over the guidewire  20  and resistance is felt, the physician checks to see if the marking on the guidewire  27  has emerged through the proximal end of the retractor  41 , as is illustrated in FIG.  6 . If the marking  27  is not yet visible, the physician must advance the retractor  30  further to ensure that it contacts the femoral artery puncture site  25 . 
     Once the retractor  30  is properly positioned within the patient&#39;s body, the surgical clip applicator  70  or other method of closing the puncture wound  25  is used. The cap  40  on the retractor  30  is first removed from the body by unscrewing (FIG.  3 ). The proximal end of the guidewire  21  emerging from the proximal end of the retractor  41  is threaded through the guide  80  located on the outer surface of the applicator  70 , as illustrated in FIG.  7 . The wings on the surgical clip applicator  77   a ,  77   b  are inserted into the hole  90  formed at the proximal end of the body of the retractor  39 , by lining up the wings  77   a ,  77   b  on the applicator  30  with the grooves  65  located on the inner surface  67  of the retractor body halves  35   a ,  35   b  (FIGS.  7  and  8 ). The wings on the clip applicator  77   a ,  77   b  are sized to fit within the grooves  65  of the retractor  30 , as is best illustrated in FIG.  8 . The clip applicator  70  is then advanced, which causes the two halves of the body of the retractor  35   a ,  35   b  to separate, as shown in FIG.  7 . As the two halves  35   a ,  35   b  separate, the patient&#39;s tissue is displaced laterally, allowing better access to the puncture site  25  in the femoral artery  10  below the overlying tissues. The clip applicator  70  is advanced through the retractor  30  until the stop on the applicator  85  contacts the proximal end of the retractor  39 . At this time, the balloon on the guidewire  24  or catheter is deflated, and the catheter and/or guidewire  20  is removed from the patient. The surgical clips located at the distal tip of the clip applicator  75  are applied to the puncture wound  25 , using the method well known to those of ordinary skill in the art. Once the femoral artery puncture wound  25  is closed, the clip applicator  70  and retractor  30  are removed from the patient. 
     First Alternate Method 
     Referring now to FIGS. 9-16, a method of using the alternate embodiment of the retractor  100  in conjunction with the dilator  150  and surgical clip applicator assembly  130  to localize and close the femoral artery puncture wound is now described. As described above, following completion of the angioplasty or angiography, the catheter used during the procedure is removed from the patient&#39;s body, leaving only the guidewire threaded into the femoral artery. If desired, before the retractor-dilator assembly  101  (FIG. 13) is used, a standard dilator of a smaller diameter than that  150  incorporated into the retractor-dilator assembly  101  can be fed onto the proximal end of the guidewire and advanced down the guidewire and into the artery. This preliminary step dilates the overlying tissue if necessary, making it easier to subsequently pass the larger retractor-dilator assembly  101  through the surrounding tissue. 
     If the tissue has been dilated as above, the smaller bore standard dilator is first removed. The proximal end of the guidewire  144  is first inserted into the distal channel  160  (FIG. 11) of the dilator  150 . The dilator  150  has been previously inserted through the internal channel of the retractor  100 , and the retractor  100  advanced over the dilator  150  until the distal tip  112  comes to rest in the notch  152  on the distal tip of the dilator  150 . The Y-connector  156  is then attached to the proximal end of the dilator  150  and a syringe  158  attached to one of the ports of the connector  156 . The retractor-dilator assembly  101  is then advanced over the guidewire  144  into the patient&#39;s body. 
     While the retractor-dilator assembly  101  is advanced into the patient&#39;s body, suction is continuously applied via the syringe  158  or other means of negative pressure (FIG. 13) to the dilator  150 . At the moment the indicator holes  154  enter the lumen of the femoral artery, blood is aspirated into the syringe  158 , indicating that the dilator  150  has been inserted through the puncture site into the femoral artery. Thus, the distal tip of the retractor  112 , still buried within the notch  152  in the dilator  150 , is located just proximal or outside the artery wall at the site of the puncture wound and the indicator holes  154  in the dilator  150  are located just distal or inside the artery lumen. 
     Alternatively, the dilator  150  includes a pressure sensor (not shown) such as a fiber optic pressure sensor, near its distal tip. The sensor is preferably mounted to the outside wall of the dilator  150 . In a preferred embodiment, a transducer-tipped pressure monitoring catheter, such as the Camino Catheter available from Camino Laboratories, San Diego, Calif., is used. The pressure sensor, mounted on the outside of the dilator  150 , is inserted over the guidewire  144  and into the femoral artery. The pressure sensor, in conjunction with a pressure monitoring system, will indicate an increase in pressure when it is inserted into the femoral artery. At that point, the advancement of the retractor  100  is stopped, such that the distal tip of the retractor  112  is located just proximal the artery wall  10  at the site of the puncture wound. This allows the physician to properly locate the site of the femoral artery puncture wound in the patient. 
     Once the dilator  150  and retractor  100  are in proper position, the cap  104  is removed from the retractor  100  and the two halves  102   a ,  102   b  of the retractor body are separated slightly (FIG. 10) by loosening the set screws  120   a ,  120   b  and sliding the two halves  102   a ,  102   b  of the retractor laterally away from one another. This causes the distal tips  112  of two halves  102   a ,  102   b  to emerge from the notch  152  in the dilator  150  (FIG. 11) and straddle the puncture site. The set screws  120   a ,  120   b , are then tightened to hold the two halves  102   a ,  102   b  of the retractor  100  in this separated position. While pressing the retractor  100  down against the outer wall of the femoral artery, the dilator  150  is withdrawn, leaving only the retractor  100  and the guidewire  144  in position at the site of the puncture wound in the artery. 
     To close the wound, the retractor  100  must be retracted far enough to allow the surgical clip applicator assembly  130  to access the puncture site. Upon loosening the set screws  120   a ,  120   b , the two halves  102   a ,  102   b  of the retractor are further separated by applying pressure on the retractor pin handle  116   c  (FIGS.  9 - 10 ). When sufficiently retracted, the set screws  120   a ,  120   b  on the retractor assembly  100  are tightened to maintain the proper distance between the retractor halves. If necessary, a separate retractor, having a thickness suited for sliding within the grooves  126  in each half  102   a ,  102   b  of the retractor body, and a width equal to that of the winged guide plate  138  (FIG. 14) of the surgical clip applicator guide assemble  134 , can be used to open the retractor body to the proper distance. 
     Second Alternate Method 
     In an alternate embodiment illustrated in FIG. 17, the modified dilator  150  having a double-sleeved inflatable balloon  170  removably attached to the distal end of the dilator  151 , just proximal to the indicator hole  154 , is used. The balloon dilator apparatus  175  is inserted over the guidewire  144  into the patient&#39;s body. As described above, as the balloon-dilator apparatus  175  is advanced, negative pressure is applied to the system via the syringe or other source. The advance of the balloon-dilator apparatus  175  is stopped as soon as blood is aspirated. The double-sleeved balloon  170  is then inflated to form a tunnel  176  between the femoral artery puncture wound and the surface of the patient&#39;s body, as illustrated in FIG.  18 . 
     The double-sleeved balloon  170  advantageously prevents the femoral artery closure retractor  100  from entering the femoral artery  10  and damaging it. Should the deflated balloon  170  be advanced into the femoral artery  10 , the process of inflating the balloon  170  will pull the balloon  170  out of the artery  10 , thereby safely creating a tunnel  176  used to access the artery  10 . 
     The balloon  170  is preferably angled at its distal end  172  to allow the balloon  170  to “fit” the femoral artery  10 , as shown in FIGS. 17-19. 
     Once the balloon  170  is inflated (FIG. 18) the retractor  100  is advanced between the two sleeves of the balloon  170 , until the distal tip of the retractor  112  reaches the distal end of the double sleeved balloon  170 . Once the retractor  100  is positioned between the two sleeves of the balloon  170 , the two halves of the retractor  102   a ,  102   b  are moved laterally away from one another, as described above. The inner sleeve  178  and the dilator  150  are removed from the patient, leaving the separated retractor  100  and the outer sleeve  180  of the balloon  170  in the patient. The dilator  150  and the inner sleeve  178  are removed from the patient along the guidewire  144 . 
     The retractor  100  and the outer sleeve of the balloon  180  form an access tunnel  182  between the femoral artery puncture wound and the surface of the patient&#39;s body, as illustrated in FIG.  20 . This tunnel  182  allows for the introduction of the wound closure device to seal the femoral artery puncture wound. 
     At this point, with the retractor providing access to the femoral artery, the proximal end of the guidewire  144  is inserted into the guidetube  136  on the surgical clip applicator assembly  130  and the wings on the guide plate are fitted within the grooves  126  of the opened retractor body  102  (FIGS.  14 - 16 ). The clip applicator assembly  130  can now be advanced toward the puncture wound, sliding within the grooves  126  in the retractor body  102 , guided by the guidewire  144  passing through the guidetube  136  at the distal tip of the surgical clip applicator assembly  130 . When the distal tip of the surgical clip applicator  130  has reached the outer wall of the femoral artery  10 , at the site of the puncture wound, the surgeon withdraws the guidewire  144  from the patient&#39;s body and immediately deploys a surgical clip. A second clip can then be deployed a millimeter or two away from the first clip in order to ensure that the wound is closed. 
     In a preferred embodiment, just prior to closure of the puncture site, the flexible guidewire  144  used during the primary procedure is replaced with a commercially available guidewire that can become rigid at its distal end, forming a hook. The hooked distal end can be pulled back, “hooking” the puncture wound in the artery. As the guidewire is pulled back further, the puncture wound is stretched into a linear slit, making it more amenable to closure by surgical clips. 
     Third Alternate Method 
     Referring now to FIGS. 21-27, a method of using the alternate embodiment of the retractor  200  in conjunction with the dilator  220  and surgical clip applicator assembly  250  to localize and close the femoral artery puncture wound is now described. As described above, following completion of the angioplasty or angiography, the catheter used during the procedure is removed from the patient&#39;s body, leaving only the guidewire  240  threaded into the femoral artery  10 . 
     The proximal end of the guidewire  240  is first inserted into the distal lumen  236  (FIG. 26) of the dilator  220 . The dilator  220  is advanced over the guidewire  240  into the patient&#39;s body. As described above, as the balloon-dilator apparatus  250  is advanced, negative pressure is applied to the system via the syringe or other source connected at the proximal end of the dilator  225 . The advance of the dilator  220  is stopped as soon as blood is aspirated through the indicator hole  228 , thus indicating that the distal end of the dilator  226  is positioned within the femoral artery  10 . The distal balloon  224  and the double-sleeved balloon  222  are then inflated to anchor the dilator  220  in place and to form a tunnel between the femoral artery puncture wound and the surface of the patient&#39;s body. 
     Once the balloons  222 ,  224  are inflated, the retractor  200  is advanced between the two sleeves  229 ,  230  of the double sleeved balloon  222 . As illustrated in FIG. 24, the inner sleeve  230  of the double sleeved balloon  222  can be in an “I” shape, which provides more space between the two sleeves to insert the two halves  202   a ,  202   b  of the reactor  200 . The retractor  200  is advanced between the two sleeves  229 ,  230 , as described above, until the distal tip of the retractor  204  is positioned just proximal to the puncture wound in the femoral artery  10 . 
     Once the retractor  200  is positioned between the two sleeves of the balloon  229 ,  230 , the two halves of the retractor  202   a ,  202   b  are moved laterally away from one another. This is done by loosening the set screws  214   a ,  214   b , and sliding one half of the retractor body  202   b  away from the other half  202   a  on the pins  212   a    212   b . The inner sleeve  230  of the double-sleeved balloon  222  and the dilator  220  are removed from the patient along the guidewire  240 , leaving the separated retractor  200  and the outer sleeve  229  of the balloon  222  in the patient. The retractor  200  and the outer sleeve of the balloon  229  form an access tunnel between the femoral artery puncture wound and the surface of the patient&#39;s body. This tunnel allows for the introduction of the wound closure device to seal the femoral artery puncture wound. 
     At this point, with the retractor  200  and outer sleeve of the balloon  229  providing access to the femoral artery  10 , the proximal end of the guidewire  240  is inserted into the distal end  262  of the indicator tube  260  which is mounted on the surgical clip applicator  252 . As described above, the distal end  262  of the indicator tube  260  having an indicator hole  264  in it is positioned so that the indicator hole  264  extends past the distal end  256  of the clip applicator  252 . The indicator tube  260  and the clip applicator  252  are advanced over the guidewire  240  while aspiration pressure is applied to the proximal end of the indicator tube  260 . As soon as blood is aspirated through the indicator hole  264 , the advancement of the indicator tube  260  and clip applicator  256  is stopped. At this point, the distal end of the surgical clip applicator  256  is positioned at the site of the puncture wound in the femoral artery  10 . Surgical clips are then applied to seal the wound. 
     Preferably, the distal end of the indicator tube  262  is curved or hooked. The hooked distal end is used to hook the puncture wound in the artery, bringing the edges of the wound together to facilitate application of the clip. Using the hooked distal end  262  of the indicator tube  260 , the puncture wound is stretched into a linear slit, making it more amenable to closure by surgical clips. 
     Fourth Alternate Method 
     Referring now to FIGS. 28-31, still another method of closing a wound in the femoral artery of a patient will be described. Here again, the femoral artery is first punctured with a hollow needle and a guidewire  350  is inserted therethrough. A proximal portion of the guidewire  351  remains outside the patient&#39;s body. After the distal end of the guidewire  353  is in position within the femoral artery, the hollow needle is removed. Diagnostic and/or therapeutic procedures are then carried out, using the guidewire  350  to guide the insertion of the other medical instruments into the vasculature of the patient. 
     Following completion of the therapeutic or diagnostic procedure, the devices used during the procedure are removed. The guidewire  350  remains in place in the patient&#39;s vasculature. When the physician desires to close the wound in the artery, he or she first mounts the retractor  300  on the distal end of the dual-lumen catheter  340 . This is done by loosening the screw  322  on one of the handles  316   b , and moving the handles  316   a ,  316   b  away from one another to separate the two halves of the retracting portion  308 , and the two parts of the retracting portion  308   a ,  308   b  are positioned around the dual-lumen catheter  340 . The dual lumen catheter  340  fits within the semicircular channel or grooves  312  formed in the inner surface of the retracting portion  308  of the retractor  300 . The two halves of the retracting portion  308   a ,  308   b  are brought together using the handles  316   a ,  316   b  to surround the catheter  340 . The retracting portion  308  is positioned on the catheter  340  just proximal to the raised portion of the catheter  354 , so the distal tip of the retracting portion  310  is located just proximal to the indicator hole  352 . Preferably, the distal tip of the retracting portion  308  will be approximately 0.5 mm behind the indicator hole  352  (see FIG.  31 ). Once in position, the screw  322  is tightened on the loop  320  to lock the two parts of the retracting portion  308   a ,  308   b  in position on the catheter  340 . 
     Once the retractor  300  is properly positioned on the dual-lumen catheter  340 , the physician inserts the proximal end  351  of the guidewire  350  into the distal end of the inner lumen  342  in the dual-lumen catheter  340 . The dual-lumen catheter  340  and retractor  300  are advanced over the guidewire  350  and into the patient. As the catheter  340  and retractor  300  are advanced, negative pressure is applied to the outer lumen of the catheter, for example, through use of a syringe  360  attached to the proximal end of the outer lumen  358 . Once the indicator hole  352  is advanced to a position inside the artery, blood will be drawn through the indicator hole  352  and will become visible in the outer lumen of the catheter  340  and the syringe  360 . At this point, advancement of the catheter  340  and retractor  300  are stopped, as the catheter  340  and retractor  300  are properly positioned in the patient. 
     Once properly positioned at the site of the puncture wound, the two halves of the retracting portion  308   a ,  308   b  are separated slightly, using the handles  316   a ,  316   b  at the proximal end  304  of the retractor  300 . To separate the retracting portions  308   a ,  308   b , the screw  322  is loosened, and the handles  316   a ,  316   b  manipulated into the desired position. The screw  322  is then tightened down upon the loop  320 , prohibiting further movement of the handles  316   a ,  316   b , and the corresponding retracting portions  308   a ,  308   b.    
     At this point, the surrounding tissues have been displaced, forming an access path to the puncture wound, and the puncture wound may be visible. The dual-lumen catheter  340  is removed from the patient by withdrawing it over the guidewire  350 . The guidewire  350  is left in place, and the wound closure device, such as a clip applicator, is inserted over the guidewire  350  to the site of the wound. Clips, such as those made of titanium or a biodegradable material, are applied to the wound, as the guidewire  350  is removed. If necessary, the artery is compressed to stop the flow of blood out of the puncture wound during the closing of the wound. The closing device is removed when the physician is confident that the wound is closed, and the retractor  300  is removed from the patient. 
     Alternatively, a separate inner catheter  360  is used in the system of present invention. In this embodiment, once the retractor  300  and dual-lumen catheter  340  are in place, and the retracting portion  308  is in an open position, the dual-lumen catheter  340  is left in place, and the guidewire  350  is withdrawn from the patient through the inner lumen  342 . An inner catheter  360  having an inflatable balloon  362  at its distal end is inserted through the inner lumen  342  and into the patient. Once the distal balloon  362  is advanced past the distal tip  346  of the dual-lumen catheter  340 , the balloon  362  is inflated. The dual-lumen catheter  340  is removed from the patient, leaving the inner catheter  360  in place. 
     To properly position the balloon inside the patient&#39;s artery, the physician can measure the distance from the distal tip of the dual-lumen catheter  346  to just outside the patient&#39;s body when the catheter  340  is properly positioned. The physician then inserts the inner catheter  360  just slightly more than that distance, to ensure that the distal balloon  362  is within the artery. The physician then pulls the inner catheter  360  in a proximal direction until resistance is felt. This will place the balloon  362  at the site of the puncture would. The balloon  362  is properly positioned just inside the artery of the patient. The balloon  362  helps to stop the flow of blood out of the puncture wound. The inner catheter  360  is used as a guide for the clip applicator or other closing device used to close the wound. The closing device is advanced until it contacts the inflated balloon  362 . As the wound is closed, the balloon  362  is slowly deflated, and the inner catheter  360  is removed from the patient. Finally, once the physician is confident that the wound is closed, the retractor  300  is removed from the patient. 
     The present invention can also be used with surgical staples or sutures. After the retractor is inserted into the patient&#39;s body and positioned at the puncture site as described above, the two halves of the retractor are separated, laterally displacing the tissues surrounding the puncture site. The retractor acts much like a dilator, gradually increasing the displacement of the overlying tissues, until the puncture wound is visible to the physician. The wound can then be closed using any acceptable means for wound closure, including surgical staples and sutures. 
     Although certain embodiments and examples have been used to illustrate and describe the present invention, it is intended that the scope of the invention not be limited to the specific embodiments set forth herein. The scope of the invention is to be defined by the claims which follow.