Abstract:
A magnet assisted surgical device, system, and method employs magnetic sections, catheters, and guidewires to modify tubular stentgrafts in-situ. One example application provides a more reliable way for surgeons to modify stentgrafts insitu to allow blood flow to continue to branching blood vessels that would otherwise be blocked by the stentgraft itself. One such method includes placing a tip section of the device in the desired location, deploying a stentgraft, placing a magnetic device inside the stentgraft, connecting the magnetic device to the tip section, and excising the portion of the stentgraft held between the magnet and the tip section.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of priority of U.S. Provisional Patent Application No. 62/089,592 to Gilani et al. filed on Dec. 9, 2014 and entitled “Magnetic Assisted In-Situ Tubular Stentgraft Fenestration,” which is incorporated by reference. 
     
    
     FIELD OF THE DISCLOSURE 
       [0002]    The instant disclosure relates to the use of magnetism to assist in the in-situ fenestration of a tubular stentgraft. 
       BACKGROUND 
       [0003]    An aortic aneurysm refers to the expanding or ballooning of the aorta, the major artery that delivers blood from the heart to the rest of the body. This expansion can result from various genetic conditions, diseases, or some underlying weakness in the wall of the aorta, often as a result of buildup of artheriosclerotic plaque. These aneurysms usually do not initially produce symptoms, however further enlargement can result in pain, numbness, embolism, or rupture often resulting in death. Over ten thousand deaths each year are directly attributable to aortic aneurysms in the United States. 
         [0004]    Aneurysms may be treated with the prescription of beta blockers, cessation of smoking, or conventional blood pressure regulation methods, among other treatments. These measures merely slow the growth of the aneurysm, but generally do not totally stop expansion. When the risks associated with surgery are outweighed by the risk of rupture, aortic aneurysms are treated via surgery. Surgical options for the treatment of an aortic aneurysm include traditional open procedures and endovascular therapy. Open surgery involves replacing the affected portion of the aorta with a synthetic graft. Often times, open surgery becomes the only repair option due to various anatomic and patient related factors. However, open surgery of the aorta can have significant physiologic impact which for some patients becomes beyond the threshold of tolerance. 
         [0005]    As an alternative to open surgery, endovascular therapy involves the placement of an endovascular stent in the aneurysm. This procedure involves the insertion of the stent into the femoral artery through an incision in the patient&#39;s thigh, and from there, into the aorta. The less invasive nature of endovascular therapy results in a reduced physiological impact when compared to open surgery. Generally, the stents used for this procedure are generalized, off-the-shelf products that can be implemented in a standard aortic aneurysm. However, when the aneurysm exists at or near a point in the aorta where a branching artery connects to the aorta, a standard stent is generally not feasible because the stent, in circumventing the aneurysm also circumvents the branch artery as well. 
         [0006]    Current solutions for this issue include custom endografts based on precise measurements obtained from CT imaging. These custom endografts generally take weeks to be manufactured and therefore are not a viable option for urgent or emergent cases. Another solution currently available to surgeons is to modify the endograft themselves prior to implantation based on similar precise CT imaging. This process can be difficult and oftentimes imprecise in practice, thus leading to challenges when the modified endograft is introduced. Further, another options available to solve this issue involves the use of chimney, periscope, snorkel, and sandwich graft techniques, commonly referred to as “CHIMPS.” This option involves the use of a variety of prefabricated grafts that include additional portions that may be used to route blood to the branch arteries. Although these techniques can achieve repair, they provide less structural stability and can be prone to failure. These problems underscore the need for a fast, reliable method of modifying stents in-situ. 
       SUMMARY 
       [0007]    The present invention is directed to apparatus, methods, and systems for magnetic assisted in-situ fenestration of tubular stentgrafts. Using the apparatuses described herein, a physician who is treating a patient diagnosed with an abdominal aortic aneurysm may insert a magnetic tip section into an artery branching off from the affected artery, inset a stentgraft into the affected artery, insert a magnetic docking section into the stentgraft causing the two magnetic sections to connect, and excise the portion of the stentgraft held between the two magnets thus allowing blood to flow from the affected artery into the branch artery despite the presence of a stentgraft that would otherwise be blocking the branch artery. The in-situ nature may allow for valuable time to be saved without the need for complex, precise CT measurements. 
         [0008]    In one embodiment, the fenestration device includes a tip section with two ends and two guidewires. The tip section may be magnetic, with one guidewire running through the tip section from one end to the opposite end, and with the other guidewire attached to the tip section. The tip section may be ogive-shaped, and may comprise neodymium, cobalt, iron, samarium, cobalt, copper, zirconium, alnico, ferrite, or some combination thereof. The guidewires may have a diameter between 0.021 inches and 0.038 inches, or a diameter between 0.014 inches and 0.021 inches. In certain embodiments there may be two catheters, one of which fits around one of the guidewires while the other catheter fits around the other guidewire. 
         [0009]    In another embodiment, the fenestration device includes a tip section, a docking section, and a guidewire attached to the tip section. Both the tip section and the docking section have a proximal and a distal end. Further, the tip section has a magnetic distal end, while the docking section has a magnetic proximal end such that the distal end of the tip section and the proximal end of the docking section can be magnetically docked. A catheter may be attached to the distal end of the docking section. Further, the guidewire used may be between 0.014 inches and 0.038 inches. Additionally, a second guidewire may run through both the tip section and the docking section. 
         [0010]    Another embodiment of the invention is a system including a tip section with a magnetic distal end, a docking section with a magnetic proximal end, three guidewires, and two catheters. The tip section slidably receives the first guidewire, allowing the first guidewire to run through its central axis. Further, the tip section attaches to the second guidewire, detachably connects to the first catheter, magnetically docks with the proximal end of the docking section which is connected to the second catheter, and slidably receives the third guidewire, allowing the third guidewire to run through its central axis. An electric hot-wire loop may be included that surrounds and is guided by the second catheter, travels along the second catheter up to the docking section, and excises a round section from the material sandwiched between the tip section and the docking section. Further, the tip section may be ogive-shaped; the tip section and the docking section may be made out of neodymium, cobalt, iron, samarium, cobalt, copper, zirconium, alnico, ferrite, or some combination thereof; the guidewires may have a diameter of between 0.021 inches and 0.038 inches or between 0.014 inches and 0.021 inches; or the second guidewire may be attached to the side of the tip section. 
         [0011]    Another embodiment of the invention is a method for the in-situ fenestration of tubular stentgrafts through the use of a magnetically assisted fenestration device. The method includes several steps. First, a magnetic tip section is placed into a vessel that branches off of a main vessel. Next, a stentgraft is deployed into the main vessel so the branching vessel is blocked by the stent. A magnetic docking section is then placed inside of the stentgraft. Next, the magnetic tip section is pulled towards the stentgraft enabling it and the magnetic docking station to magnetically dock. The two docked sections are then used as a guide to navigate a fenestration element to the stentgraft where the fenestration element then excises a portion of the stentgraft. 
         [0012]    The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter that form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. The novel features that are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    For a more complete understanding of the disclosed system, apparatus, and methods, reference is now made to the following descriptions taken in conjunction with the accompanying drawings. 
           [0014]      FIG. 1  is an illustration showing a tip section of a fenestration device configured to aid in the in-situ fenestration of tubular stentgrafts according to one embodiment of the disclosure. 
           [0015]      FIG. 2  is an illustration showing a tip section of a fenestration device connected to a catheter according to one embodiment of the disclosure. 
           [0016]      FIG. 3  is an illustration showing a tip section of a fenestration device detached from a catheter according to one embodiment of the disclosure. 
           [0017]      FIG. 4  is an illustration showing a tip section of a fenestration device according to one embodiment of the disclosure wherein an inner catheter, an outer catheter, and an inner channel within the tip section are visible. 
           [0018]      FIG. 5  is an illustration showing a tip section of a fenestration device according to one embodiment of the disclosure wherein an outer catheter has been detached while an inner catheter remains connected to the tip section. 
           [0019]      FIG. 6  is an illustration showing a tip section of a fenestration device according to one embodiment of the disclosure wherein both an outer catheter and an inner catheter have been detached from the tip section. 
           [0020]      FIG. 7  is an illustration showing a docking section of a fenestration device according to one embodiment of the disclosure wherein the docking station is connected to an inner catheter and an outer catheter. 
           [0021]      FIG. 8  is an illustration showing an electric hot-wire loop of a fenestration device according to one embodiment of the disclosure. 
           [0022]      FIG. 9  is an illustration showing the interaction between an electric hot-wire loop section and a docking section of a fenestration device according to one embodiment of the disclosure. 
           [0023]      FIG. 10  is an illustration showing the interaction between a tip section of a fenestration device, a docking section of a fenestration device, an electric hot-wire loop section of a fenestration device, and a stentgraft, according to one embodiment of the disclosure. 
           [0024]      FIG. 11  is an illustration showing the configuration of a fenestration device at the time where a portion of a stentgraft is excised, according to one embodiment of the disclosure. 
           [0025]      FIG. 12  is a block diagram explaining the steps involved in magnet assisted in-situ fenestration of a stentgraft according to one embodiment of the disclosure. 
           [0026]      FIG. 13  is an illustration showing a tip section of a fenestration device being positioned in the desired location in vivo, according to one embodiment of the disclosure. 
           [0027]      FIG. 14  is another illustration showing a tip section of a fenestration device being positioned in the desired location in vivo, according to one embodiment of the disclosure. 
           [0028]      FIG. 15  is yet another illustration showing a tip section of a fenestration device being positioned in the desired location in vivo, according to one embodiment of the disclosure. 
           [0029]      FIG. 16  is an illustration showing the placement of a stentgraft and the use of a docking section of a fenestration device, according to one embodiment of the disclosure. 
           [0030]      FIG. 17  is an illustration showing the final configuration of a fenestration device before a portion of the stentgraft is excised, according to one embodiment of the disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0031]      FIG. 1  is an illustration showing a tip section of a fenestration device configured to aid in the in-situ fenestration of tubular stentgrafts according to one embodiment of the disclosure. An in-situ fenestration device may include a guidewire  102  that enters the proximal end  104  of the tip section  120  and runs through the body of a tip section  120  of the fenestration device. The guidewire  102  is fed into the vessel where the physician desires to place the tip section  120  and is used to guide the tip section  120  into said vessel. The tip section  120  may comprise a plurality of sub-sections  122 ,  124 ,  126 . The portion  122  may be made of soft material similar to current catheters to not injury the artery it is being advanced into the artery. The portion  122  may be used to guide a dilator similar to that of a sheath of conventional stents. The portion  124  may serve as the junction between the portions  122  and  126 . A second guidewire  106  may be mounted to the tip section  120 , and may be affixed to any part of the tip section  120 . The second guidewire  106  may be used, once the tip section  120  is in place, to pull the tip section  120  back out its initial placing. One embodiment is shown in  FIG. 1  wherein the guidewire  106  is attached to the side of the tip section  120 . The guidewire  102  may exit the tip section  120  at the distal end  108 . 
         [0032]    The in-situ fenestration device may include additional elements such as catheters to aid in the insertion of guidewires into a patient.  FIG. 2  is an illustration showing a tip section of one such fenestration device configured to aid in the in-situ fenestration of tubular stentgrafts according to one embodiment of the disclosure. In this embodiment, the fenestration device may include a catheter  202  which is detachably connected to the tip section  120 . The catheter  202  is used by the physician to help guide the tip section  120  along the guidewire  102  so that the tip section can be initially placed in the desired location. 
         [0033]    The tip section  120 , in order to be positioned in the desired location, may be detachable from the catheter(s) themselves. For example,  FIG. 3  is an illustration showing a tip section of a fenestration device configured to aid in the in-situ fenestration of tubular stentgrafts according to one embodiment of the disclosure wherein, the tip section  120  is shown detached from the catheter portion  202  of the device. The detachment of the catheter allows for the tip section  120 , once in the desired location to be left there, while the catheter  202  is then removed from the patient. 
         [0034]    Further, the tip section  120  and any accompanying catheters may allow for guidewires to pass coaxially through them. For example,  FIG. 4  is an illustration showing a tip section of a fenestration device configured to aid in the in-situ fenestration of tubular stentgrafts according to one embodiment of the disclosure in which the tip section  120  may have having a proximal end  104  and a distal end  108 . A tubular lumen  402  may extend through the tip section  120  from the proximal end  104  to the distal end  108 . The tubular lumen  402  would allow for guidewires to be passed coaxially through the tip section  120  and any attached catheters. Two coaxial catheters  404 ,  202  may be detachably connected to the distal end  108  of the tip section  120  of the fenestration device. The smaller catheter  404  may be either independent from or attached to the larger catheter  202 . These catheters  404 ,  202  allow for a guidewire  102  to be passed through up the catheters  404 ,  202  and the tip section  120  in order to aid the physician in placing the tip section  120  into the desired location before detaching the catheters and removing them from the patient. The catheters  404  (and catheter  706  described below) ay be sized such that their lumen is completely occluded by the guide wire, such as sizes of 0.035 or 0.038. 
         [0035]    The present invention may include features that provided flexibility and options to physicians when practicing the disclosed fenestration device. For example,  FIG. 5  is an illustration showing a tip section  120  configured so that it may be detached from a catheter  202 . The proximal end of the detached catheter  502 , and the catheter itself  202 , may still surround the coaxial inner catheter  404 . In this depiction of an embodiment, the inner catheter  404  may still be detachably connected to the distal end  108  of the tip section  120  of the fenestration device. The independent detachability may allow physicians more options to handle their patient&#39;s individual needs or more effectively respond to situations that arise during the procedure. 
         [0036]    Each element of the apparatus may be independent from each other element, while simultaneously allowing for them to interact, connect to, or be guided by other elements. For example,  FIG. 6  is an illustration showing a tip section  120  according to one embodiment of the disclosure that has been detached from both the proximal end of the inner catheter  602  and the proximal end of the outer catheter  502 . Therefore, the inner catheter  404  and the outer catheter  202  may both be independent and detachable from the tip section  120  of the fenestration device. 
         [0037]    In reference to the guidewires, in one embodiment of the disclosure, the first guidewire  102  may have a diameter of 0.035 inches (0.89 mm), but in other embodiments the first guidewire  102  may have a diameter of 0.014 inches (0.36 mm), 0.018 inches (0.46 mm), 0.021 inches (0.53 mm), 0.025 inches (0.64 mm), 0.032 inches (0.81 mm), or 0.038 inches (0.97 mm). Further, in one embodiment of the disclosure, the second guidewire  106  may have a diameter of 0.014 inches (0.36 mm), but in other embodiments the second guidewire  106  may have a diameter of 0.018 inches (0.46 mm), 0.021 inches (0.53 mm), 0.025 inches (0.64 mm), 0.032 inches (0.81 mm), 0.035 inches (0.89 mm), or 0.038 inches (0.97 mm). Because all guidewire sizes are viable, all suitable guidewires are contemplated and the choice of which to use depends on the specific patient being treated and the specifics of that patient&#39;s condition. 
         [0038]    With regards to the tip section  120 , the first guidewire  102  runs coaxially through the tubular lumen  402  of the tip section  120 . In this embodiment, the first guidewire  102  is not connected to the tip section  120 , thus allowing the tip section to slide freely along the guidewire  102 . Also according to this embodiment, the second guidewire  106  is permanently affixed to the side of the tip section  120 . The second guidewire  106  may be attached at such an angle to easily allow for the second guidewire to extend distally along the same path as the first guidewire  102 , large catheter  202 , and small catheter  404 . In one embodiment, the second guidewire  106  is attached to the tip section via vibration welding. However, all suitable methods of attachment are contemplated. For example, in one embodiment of the disclosure, the second guidewire  106  is attached by inserting the guidewire  106  into a channel on the tip section and kinking the guidewire  106  such that the guidewire  106  cannot be removed from the tip section  120  when force is applied to either. In yet another embodiment, the guidewire  106  may be glued to the tip section  120 . 
         [0039]    The distal end  108  may be magnetic. The tip section  120  might not be a homogeneous material, but instead may have the distal end  108  alone made of a magnetic material. Alternatively, the tip section  120  as a whole may be magnetic and thus may be made of a single material. In one embodiment, the magnetic portion of the tip section  120  is comprised of one or more rare earth metals. One skilled in the art would understand rare earth metals to identify a type of strong permanent magnets made from combinations or alloys of rare earth elements. Such rare earth elements include, but are not limited to Scandium (Sc), Yttrium (Y), Lanthanum (La), Cerium (Ce), Praseodymium (Pr), Neodymium (Nd), Promethium (Pm), Samarium (Sm), Europium (Eu), Gadolinium (Gd), Terbium (Tb), Dysprosium (Dy), Holmium (Ho), Erbium (Er), Thulium (Tm), Ytterbium (Yb), and Lutetium (Lu). Additionally, one skilled in the art would understand that in addition to these rare earth elements, rare earth magnets may comprise additional elements including, but not limited to, Iron (Fe), Nickel (Ni), Cobalt (Co), Aluminum (Al), Copper (Cu), Titanium (Ti), and Boron (B). These magnetic characteristics may allow the tip section  120  to further interact and magnetically dock with other portions. 
         [0040]    The tip section may be ogive-shaped. A person having ordinary skill in the art would understand the description “ogive” to refer to an object having a roundly tapered end. For example, the tip section  120  of the device is in the shape of a bullet. This shape allows the bullet to more easily pass within vessels by reducing the risk of the vessels being damaged. Additionally, the tip section  120  may include a tubular lumen  402  running coaxially from its proximal end  104  to its distal end  108 . The tubular lumen  402  may have a diameter of 0.035 inches, but may alternatively have a diameter of 0.014 inches (0.36 mm), 0.018 inches (0.46 mm), 0.021 inches (0.53 mm), 0.025 inches (0.64 mm), 0.032 inches (0.81 mm), or 0.038 inches (0.97 mm) to fit the various guidewire sizes that may be used in conjunction with the tip section  120 . 
         [0041]    In reference to the catheters, the small catheter  404  may run coaxially with the larger catheter  202 . Both the small catheter  404  and the larger catheter  202  may be detachably connected from the tip section  120 . The size of the larger catheter  202  (and larger catheter  708  shown below) may be dependent upon the diameter of the magnets that are selected and based on a diameter of the vessel being cannulated. In one embodiment, the small catheter  404  is French gauge  4  catheter, but in other embodiments the small catheter  404  may be French gauge  3 ,  5 ,  6 , or  7 . Because all catheter sizes are viable, all suitable catheters are contemplated and the choice of which to use depends on the size guidewires being used, the specific patient being treated, and the specifics of that patient&#39;s condition. 
         [0042]    In addition to the tip section  120 , the apparatus may include a complementary docking section that magnetically interacts with the tip section. These two sections, when acting together, may be used to isolate a portion of the stentgraft such that the portion may be excised. 
         [0043]      FIG. 7  is an illustration showing a docking section of a fenestration device configured to aid in the in-situ fenestration of tubular stentgrafts according to one embodiment of the disclosure. A docking section  704  is connected to two coaxial catheters: a large catheter  708  and a smaller catheter  706 . The lumen of the smaller catheter continues through the tubular lumen  702  that runs through the docking section  704  such that a guidewire may coaxially run thought both the docking section  704  and the catheters  706 ,  708 . The large catheter  708  connects to the docking station and surrounds the smaller catheter  706 . 
         [0044]    As with the tip section  120 , the docking section  704  may be magnetic. In one embodiment, the docking section  704  is comprised of one or a combination of rare earth metals. One skilled in the art would understand rare earth metals to identify a type of strong permanent magnets made from combinations or alloys of rare earth elements. Such rare earth elements include, but are not limited to Scandium (Sc), Yttrium (Y), Lanthanum (La), Cerium (Ce), Praseodymium (Pr), Neodymium (Nd), Promethium (Pm), Samarium (Sm), Europium (Eu), Gadolinium (Gd), Terbium (Tb), Dysprosium (Dy), Holmium (Ho), Erbium (Er), Thulium (Tm), Ytterbium (Yb), and Lutetium (Lu). Additionally, one skilled in the art would understand that in addition to these rare earth elements, rare earth magnets may comprise additional elements including, but not limited to, Iron (Fe), Nickel (Ni), Cobalt (Co), Aluminum (Al), Copper (Cu), Titanium (Ti), and Boron (B). These magnetic characteristics allow the docking section to further magnetically interact with a tip section  120 . 
         [0045]    The docking section  704  may have a cylindrical shape and connect with catheters  706 ,  708  on one of the two flat cylinder faces. The docking section  704  may additionally have a tubular lumen  702  that runs from one cylinder face to the opposite face in order to allow guidewires to be passed through it. In one embodiment, the tubular lumen  702  has a diameter of 0.035 inches, but may alternatively have a diameter of 0.014 inches (0.36 mm), 0.018 inches (0.46 mm), 0.021 inches (0.53 mm), 0.025 inches (0.64 mm), 0.032 inches (0.81 mm), or 0.038 inches (0.97 mm) to fit the various guidewire sizes that may be used in conjunction with the docking section  704 . 
         [0046]    In reference to the catheters that could be used in connection with a docking section  704 , in one embodiment, the small catheter  706  runs coaxially with the larger catheter  708 . Both the small catheter  706  and the larger catheter  708  may be permanently attached to the docking section  704 . In one embodiment, the small catheter  706  is French gauge  4  catheter, but in other embodiments the small catheter  706  may be French gauge  3 ,  5 ,  6 ,  7 , or  8 . Because all catheter sizes are viable, all suitable catheters are contemplated and the choice of which to use depends on the size guidewires being used, the specific patient being treated, and the specifics of that patient&#39;s condition. 
         [0047]    The apparatus may additionally include an element that has the capability of excising a portion of the surgical stentgrafts used by the physician to treat an aneurysm.  FIG. 8  in an illustration showing an electric hot-wire loop section of a fenestration device configured to aid in the in-situ fenestration of tubular stentgrafts according to one embodiment of the disclosure. The fenestration portion of the electric hot-wire loop  802  may be located at the proximal end of the body of the fenestration section  804 . The electric hot-wire loop section of the fenestration device creates heat for the purpose of cutting material by applying an electrical current across an exposed wire loop  802  thereby causing the wire loop  802  to generate heat. The current necessary to cause the fenestration portion of the electric hot-wire loop  802  to be used as a cutting implement is fed to the loop  802  through wires running up the body of the fenestration section  804 . The loop form of the fenestration portion  802  allows for a guidewire or catheter to run through the loop and thus guide the loop to a desired location. 
         [0048]    The electric hot-wire loop and the docking section may be configured to interact with one another.  FIG. 9  is an illustration showing an embodiment of such an interaction configured to aid in the in-situ fenestration of tubular stentgrafts. A fenestration portion of an electric hot-wire loop  802  surrounds and is guided by a catheter  708  attached to a docking section  704  of the device. The body of the fenestration section  804  extends distally, approximately parallel to the catheter  708 . In one embodiment, the fenestration portion of the electric hot-wire loop  802  may be larger in diameter than the outer diameter of the catheter  708  so that the hot-wire loop  802  fits around and can be slid along the catheter  708 . 
         [0049]    Bringing many of the described components together,  FIG. 10  is an illustration showing an embodiment of the interaction between a tip section  120 , a docking section  704 , and a hot-wire loop section of a fenestration device  802  configured to aid in the in-situ fenestration of tubular stentgrafts according to one embodiment of the disclosure. A tip section  120  is positioned on the exterior of a tubular stentgraft  1004 . The tip section  120  is magnetically docked with a docking section  704  which is positioned on the interior of the tubular stentgraft  1004  directly opposite the tip section  120 . A catheter  708  is attached to the docking section  704  and said catheter  708  extends out the distal end of the tubular stentgraft  1004 . The fenestration portion of an electric hot-wire loop  802  surrounds and is guided by the catheter  708 . The body of the fenestration potion  804  may extend distally from the fenestration portion of the electric hot-wire loop  802 , and runs approximately parallel to the catheter  708 . The fenestration portion of the electric hot-wire loop  802  may be fed up along the catheter  708  until it comes into contact with the portion of the stentgraft nearby the docking section  704 . Once the fenestration portion  802  comes into contact with the stentgraft, the hot-wire loop  802  may be activated, thereby excising the portion of the stentgraft held between the tip section  120  and the docking section  704 . A sharp-tipped guidewire  1002  runs through the tip section  120 , the tubular stentgraft  1004 , the docking section  704 , and the catheter  708 . The sharp-tipped guidewire  1002  is used to ensure that the tip section  120 , and the docking section  704  are lined up in a desired configuration such that the lumen within each piece allows for the sharp-tipped guidewire  1002  to run through both sections. 
         [0050]    Further illustrating the interaction between certain components,  FIG. 11  shows an embodiment of how a hot-wire loop section of a fenestration device excises a portion of a tubular stentgraft. A tip section  120  is situated directly opposite from a magnetically docked docking section  704 , with only a tubular stentgraft  1004  separating the two sections. A fenestration portion of an electric hot-wire loop  802  has advanced along the catheter  708  it surrounds such that the fenestration portion makes contact with the tubular stentgraft  1004 , thus excising a portion of the stentgraft. The body of the fenestration section  804  runs distally away from the fenestration portion  802  approximately parallel to the catheter  708 . A sharp-tipped guidewire  1002  runs coaxially through the tip section  120 , the tubular stentgraft  1004 , the docking section  704 , and the catheter  708 . 
         [0051]    A method of magnet assisted in-situ fenestration of a stentgraft may be described with respect to the flow chart of  FIG. 12 . A tip section  120  is placed into a branch vessel at block  1202 . A surgical stentgraft  1004  is deployed into the main vessel at block  1204  thereby blocking the branch vessel containing the tip section  120 . Next, the docking station  704  is placed into the stentgraft  1004  at block  1206 . The tip section  120  is then pulled towards the stentgraft  1004  such that it causes the tip section  120  and the docking section  704  to magnetically dock at block  1208 . Next, an electric hot-wire loop  802  is guided at block  1210  to the location where the tip section  120  and the docking section  704  are docked. Then, the electric hot-wire loop is used to excise the stentgraft portion held between the tip section  120  and the docking section  704  at block  1212 . 
         [0052]    Further explaining initial steps of the method in certain embodiments,  FIG. 13  illustrates how and where the tip section  120  is placed into the desired location according to one embodiment of the disclosure. Initially, a guidewire  102  may be passed up an entry vessel  1308 , through the main vessel  1302 , and into a branching vessel  1304 . Then, a tip section  120  along with any detachably connected catheters  202  may be passed along the guidewire  102 . A guidewire  106  may be attached to the side of the tip section  120 .  FIG. 14  continues the illustration of  FIG. 13  according to one embodiment of the disclosure. In  FIG. 14 , the tip section  120  may be detached from both a small catheter  404  and a larger catheter  202 . Next, the two catheters  202 ,  404  may then be removed from the patient&#39;s body.  FIG. 15  continues the illustration of  FIG. 13  and  FIG. 14 , and demonstrates the side-attached guidewire  106  being used to advance the tip section  120  along the guidewire  102  until the tip section  120  is placed as deeply into the branching vessel  1304  as the vessel diameter will permit. A catheter may then be placed over the side-attached guidewire  106  in order to increase column strength to further enable the advancement of the tip section  120  along the guidewire  102 . Once the tip section  120  is in the desired location, the guidewire  102  may be withdrawn from the branching vessel and removed from the patient&#39;s body. 
         [0053]      FIG. 16  further illustrates how to excise the desired portion of the stentgraft  1004  once the tip section is in place, according to one embodiment of the disclosure. Once the tip section  120  is in place in the branching vessel  1304 , a stentgraft  1004  may be deployed in a position to bypass the aneurysm  1602  that has occurred in the main vessel  1302 . Once the stentgraft  1004  is in place, a docking section  704  along with at least one attached catheter  708  may be passed into the stentgraft.  FIG. 17  continues the illustration of  FIG. 16 . In  FIG. 17 , one embodiment of the disclosure is shown as the side-mounted guidewire  106  is pulled causing the tip section  120  to be pulled towards the stentgraft  1004 . As the tip section  120  comes into contact with the stentgraft  1004 , it may magnetically dock with the docking section  704  with only a portion of the stentgraft  1004  held between the tip section  120  and the docking section  704 . Once the magnetic docking as occurred, a sharp-tipped guidewire  1002  may be passed through any catheter  708  attached to the docking section  704 , the docking section  704 , the portion of the stentgraft held between the two magnets, and the tip section  120 . The sharp-tipped guidewire  1002  in this context is used to ensure that the tip section  120  and the docking section  704  are lined up in the desired configuration. Lastly, an electric hot-wire loop  802 ,  804  may be passed over the catheter  708  until it comes into the contact with the stentgraft  1004 , where it excises the portion held between the tip section  120  and the docking section  704 . 
         [0054]    According to one embodiment of the disclosure, the main vessel  1302  is the patient&#39;s aorta. The branching vessel  1304  may be a renal artery, but in other embodiments the branching vessel  1304  may include the gonadal arteries, lumbar arteries, inferior or superior mesenteric arteries, median sacral artery, or the celiac trunk. In one embodiment, the entry vessel  1308  refers to one of the common iliac arteries. 
         [0055]    Although the present disclosure and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the disclosure as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the present invention, disclosure, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present disclosure. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.