Variable stiffness optical fiber shaft

Information

  • Patent Grant
  • 6352531
  • Patent Number
    6,352,531
  • Date Filed
    Wednesday, March 24, 1999
    25 years ago
  • Date Issued
    Tuesday, March 5, 2002
    22 years ago
Abstract
The variable stiffness optical fiber shaft includes an optical fiber and a reinforcing tube with apertures formed around the surface of the reinforcing tube, and at least one coaxial outer layer of a polymer, metal, or both for providing desired variations in stiffness along at least a portion of the length of the shaft. The apertures can be formed as axial or helical slits in the surface of the reinforcing tube, and the reinforcing tube can also be formed to be tapered at the point where the apertures are formed in the reinforcing tube to provide an optical fiber shaft that is torqueable and pushable at the proximal end, yet soft and flexible at the distal end.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




This invention relates generally to interventional medical devices, and more particularly concerns an optical fiber composite shaft having variable stiffness for enhanced performance of the composite shaft when used with or without a guide catheter, or as a stand-alone flow directed device for use in the vascular system as part of an imaging system, a therapeutic system or for delivery of medical devices.




2. Description of Related Art




Conventional minimally invasive catheter based therapies typically require guide wires that are one to two meters long extending through a longitudinal lumen in the catheter, and that are torqueable and pushable at the proximal end, yet soft and flexible at the distal end. Many such guidewires are made of stainless steel or the like, and are ground to tapers which provide the desired bending properties along the guidewire. Recently, numerous minimally invasive sensing and actuation procedures have been developed which benefit from the unique qualities of an optical fiber to deliver optical light or power to the distal tip of the optical fiber. For example, optical fiber based technology can be used for imaging, treatments such as “thrombolyzing” blood or cutting tissue by use of high energy light delivered through the end of the optical fibers, and for the delivery of therapeutic agents, such as timed release agents or embolics. However, conventional optical fiber technology has not been easily adaptable to such applications, particularly when the optical fiber must also act as a guidewire, either within a catheter or as a stand-alone device, since optical fibers, when used alone, are not very torqueable, pushable or resilient when compared to guide wires made from a variety of other, more rigid, materials. Also, small diameter optical fibers are quite “floppy”, while larger diameter fibers can be too stiff to maneuver through sharp bends, and the use of optical fibers as guidewires or pushers within catheters can thus be difficult and quite technique sensitive.




An abdominoscope is known that includes a tubular sheath having a series of strips separated by longitudinal slots, and an elongate, steerable, flexible medical implement is also known that has a tubular body with a controllable steering region formed from flexible steering ribbons made of flexible materials, such as Nitinol, spring steel, nylon, or other plastic material. In addition, a steerable medical probe is also known that has a torque tube with spaced apart slots to impart additional flexibility to the torque tube, with a thin-walled connecting portion serving as a rib or backbone. However, there remains a need for a way of creating variable stiffness along an optical fiber shaft, without a decrease in the torquability, pushability and resistance to fracture of the optical fiber shaft.




It would also be desirable to provide an optical fiber shaft with variable stiffness to allow optical fibers to be more pushable at the proximal end and more trackable at the distal end, and to make the use of optical fibers in catheter-based therapies more straight forward and less technique sensitive. The present invention addresses these and numerous other needs.




SUMMARY OF THE INVENTION




Briefly, and in general terms, the present invention provides for a variable stiffness optical fiber shaft formed from an optical fiber and a reinforcing tube over at least a portion of the optical fiber, with apertures being formed around the surface of the reinforcing tube and extending in a direction between the proximal and distal ends of the optical fiber, to provide variable stiffness to the optical fiber shaft. By use of the invention, a variable stiffness shaft can be made which is more pushable at the proximal end and more trackable at the distal end, with the capability to provide a wide range of predictable variations in stiffness and other structural parameters over the length of the shaft. A variable stiffness optical fiber shaft constructed according to the invention can be used in conjunction with a guide catheter or as a flow directed, stand alone catheter.




By using the construction according to the invention, coating or heat shrinking a heat shrinkable material on the outside diameter of the optical fiber will improve tracking of the device, and a taper can also be ground onto the optical fiber shaft to yield a shaft with a stiffer, more manageable, proximal end and a softer, more maneuverable, distal tip. The variable stiffness optical fiber shaft advantageously can also thus be constructed from a minimum number of components, with the apertures in the reinforcing tube eliminating the need for a braid or transitional sections from the stiffer proximal zone to the softer distal zone.




The invention accordingly provides in a presently preferred embodiment for a variable stiffness optical fiber shaft for use in vascular interventional therapy, such as for use within a tortuous, small diameter vessel such as those found in the vasculature of the brain. The variable stiffness optical fiber shaft comprises an optical fiber having a proximal end and a distal end, a reinforcing tube attached to the optical fiber, with the optical fiber extending through the reinforcing tube, and the reinforcing tube having a surface defining a plurality of apertures extending in a direction between said proximal and distal ends of said optical fiber, and at least one coaxial outer layer of a polymer, metal, or both provided over at least a portion of the reinforcing tube and the optical fiber, for providing desired variations in stiffness along at least a portion of the length of the shaft. The reinforcing tube is preferably a metal tube, such as a hypo tube, and can be formed of stainless steel or an alloy of nickel and titanium, for example.




In one presently preferred embodiment, the apertures can be formed as longitudinal, axial slits, slots, channels, or grooves in the surface of the reinforcing tube, and in an alternate preferred embodiment, the apertures can be formed as helical or radial slits, slots, channels, or grooves in the surface of the reinforcing tube, providing variable stiffness to the optical fiber shaft. The outer surface of the reinforcing tube can also be formed to be tapered at the point where the apertures are formed in the reinforcing tube, particularly at a distal portion of the optical fiber, to provide an optical fiber shaft that is torqueable and pushable at the proximal end, yet soft and flexible at the distal end. Alternatively, the apertures can be formed transversely in the surface of the reinforcing tube in an area where such a configuration will produce desired results.




The one or more coaxial layers can be formed of heat shrink polymeric material, such as polyethylene, polytetrafluoroethylene (PTFE) polyethylene terephthalate (PET), polyetherethylketone (PEEK), polyphenylenesulfide (PPS), or any of a variety of other polymers which can be fabricated into a structure and necked or shrunk over a shaft, or can be formed of metal. While the invention can effectively use tubes which are placed over the exterior of the optical fiber shaft and then heat shrunk or bonded by adhesive to the fiber, it is also contemplated that the shaft can be reinforced by other longitudinally extending additional structures with varying cross sections for certain specific applications.




The heat shrink tubing is placed on the fiber, and then heat can be applied to the heat shrink tubing, resulting in shrinkage of the heat shrink tubing to encapsulate the fiber. The structure formed by the apertures in the surface of the reinforcing tube, in combination with the distal taper of the reinforcing tube and outer coaxial sheath, allows the proximal part of the composite shaft to be relatively stiff, and the distal tip to be flexible and soft. A variety of other techniques can be used within the scope of the invention to accomplish the variable stiffness of the optical fiber shaft.




Those skilled in the art will also recognize that, while the invention has been described in the context of optical fibers, other, equally non-structural fibers used for therapeutic or measurement purposes may also benefit from the invention.




These and other aspects and advantages of the invention will become apparent from the following detailed description and the accompanying drawings, which illustrate by way of example the features of the invention.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1A

is a schematic view of a first preferred embodiment of a variable stiffness optical fiber shaft according to the invention.





FIG. 1B

is a schematic view of a first preferred embodiment of a variable stiffness optical fiber shaft according to the invention.





FIG. 2A

is a schematic view of an alternate preferred embodiment of a variable stiffness optical fiber shaft according to the invention.





FIG. 2B

is a schematic view of an alternate preferred embodiment of a variable stiffness optical fiber shaft according to the invention.





FIG. 3A

is a schematic view of another alternate preferred embodiment of a variable stiffness optical fiber shaft according to the invention.





FIG. 3B

is a schematic view of another alternate preferred embodiment of a variable stiffness optical fiber shaft according to the invention.





FIG. 3C

is a schematic view of another alternate preferred embodiment of a variable stiffness optical fiber shaft according to the invention.





FIG. 4A

is a schematic view of another alternate preferred embodiment of a variable stiffness optical shaft according to the invention.





FIG. 4B

is a schematic view of another alternate preferred embodiment of a variable stiffness optical shaft according to the invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




Modern interventional medical procedures have relied on ever smaller and more flexible devices to reach areas requiring treatment which were previously inaccessible to conventional devices, such as by the placement of vasoocclusive devices in tiny areas of damaged vasculature such as aneurysms or ruptures in arteries in the brain. Some devices to treat such areas use optical fibers to carry light energy to remote locations at the distal end of the optical fiber, but certain limitations have been found in currently available optical fibers for those purposes.




For example, conventional optical fiber technology has not been easily adaptable to catheter based imaging, treatments such as “thrombolyzing” blood or cutting tissue, or to the delivery of therapeutic agents, such as timed release agents, or embolics, since optical fibers, when used as a stand alone structural device, are not very torqueable, pushable or resilient. Small diameter optical fibers of the type most useful for such therapies frequently can become too floppy, while larger diameter fibers can be too stiff to maneuver through sharp bends, and for these reasons, the use of optical fibers as stand alone guidewires or catheters can be difficult and technique sensitive. Also, since there are practical limits to the diameter of the fiber for specific applications, the use of reinforced guide catheters with longitudinal lumens through which the optical fiber passes can place important restrictions on how small such an assembly can be. Further, if the optical fiber is to be used with both a guidewire and a guiding catheter, there are limits imposed on the techniques that can be employed because of the necessarily larger diameter of such an assembly to accommodate the requirements of the two different shafts within the catheter.




As is illustrated in the drawings, which are provided for the purposes of illustration and not by way of limitation, one preferred embodiment of the invention illustrated in

FIGS. 1 and 2

is embodied in a variable optical fiber shaft


10


that comprises an optical fiber


12


having a proximal end


14


and a distal end


16


. The optical fiber


12


is surrounded by a reinforcing tube


18


, such as a metal tube, which can for example be a stainless steel hypo tube, although the reinforcing tube may also be formed of a nickel titanium alloy, such as NITINOL. The reinforcing tube can be cylindrical as shown in

FIG. 1

, or may be tapered along its length, either in steps or continuously in order to provide a desired and pushability. In one presently preferred embodiment, the reinforcing tube is advantageously provided with a plurality of longitudinal, axially oriented apertures, such as slits, slots, channels, or grooves


20


formed around the surface of a portion of the reinforcing tube to provide an optical fiber shaft that is torqueable and pushable at the proximal end, yet soft and flexible at the distal end. As is illustrated in

FIG. 1A

, the apertures can be formed in the surface of the reinforcing tube, such as by laser cutting, for example, and allow the reinforcing tube to have the same diameter, or a tapering diameter, with variable stiffness. In a presently preferred alternate embodiment illustrated in

FIG. 1B

, in which like elements are designated with like reference numerals, the apertures can be formed as groups


20


′ of round holes


21


, arranged so as to be longitudinal, and axially oriented around the surface of a portion of the reinforcing tube, so as to provide an optical fiber shaft that is torqueable and pushable at the proximal end, yet soft and flexible at the distal end.




Alternatively, as is illustrated in

FIG. 2A

, in which like elements are designated with like reference numerals, the apertures can be formed in the surface of the reinforcing tube by grinding. In another presently preferred aspect illustrated in

FIG. 2A

, the outer surface of the reinforcing tube can also be formed to have a taper


22


at the point where the apertures are formed in the reinforcing tube, such as by grinding or laser cutting, particularly at a distal portion of the optical fiber, to provide an optical fiber shaft that is torqueable and pushable at the proximal end, yet soft and flexible at the distal end. In a presently preferred alternate embodiment illustrated in

FIG. 2B

, in which like elements are designated with like reference numerals, the apertures can be formed as groups


20


′ of round holes


21


, such as by laser cutting, at a distal portion of the optical fiber, to provide an optical fiber shaft that is torqueable and pushable at the proximal end, yet soft and flexible at the distal end.




Referring to

FIGS. 1A

,


1


B,


2


A and


2


B, in a currently preferred embodiment, at least one coaxial outer covering or sheath


24


is also provided over at least a portion of the optical fiber and reinforcing tube, for providing desired variations in stiffness along at least a portion of the length of the shaft. Such an outer sheath is currently preferably a heat shrink polymer, such as polyethylene, PTFE, PEEK, PET or PPS, for example, although other similar heat shrink polymers may also be suitable. Alternatively, the outer sheath can be a metal tube, such as a metal tube formed from a nickel titanium alloy, for example, that can be bonded adhesively over the outer surface of the optical fiber, such as by cyanoacrylate adhesive. Alternatively, where the reinforcing tube is sufficient to provide the desired variable stiffness characteristics to the optical fiber, the outer sheath may be omitted.




In another presently preferred embodiment, illustrated in

FIG. 3A

, a variable stiffness optical fiber shaft


30


is provided that comprises an optical fiber


32


having a proximal end


34


and a distal end


36


. The optical fiber


32


is surrounded by a reinforcing tube


38


, such as a metal tube, which can for example be a stainless steel hypo tube, although the reinforcing tube may also be formed of a nickel titanium alloy, such as NITINOL. The reinforcing tube can be cylindrical as shown in

FIGS. 1A and 1B

, or may be tapered along its length, either in steps or continuously in order to provide a desired stiffness and pushability. At least one coaxial outer covering of sheath


24


is also provided over at least a portion of the optical fiber and reinforcing tube, as discussed above. In one presently preferred embodiment, the reinforcing tube is advantageously provided with a plurality of helically arranged apertures


40


formed as slits, channels or grooves around the surface of a portion of the reinforcing tube to provide an optical fiber shaft that is torqueable and pushable at the proximal end, yet soft and flexible at the distal end. Alternatively, the apertures may be radially arranged apertures formed as slits, channels or grooves. In another presently preferred embodiment, illustrated in

FIG. 3B

, the apertures


40


′ can be axially oriented, helically arranged apertures formed as slits, channels or grooves. The apertures can be formed in the surface of the reinforcing tube by grinding or laser cutting, and allow the optical fiber shaft to have a constant diameter, or a tapering diameter, from the proximal to the distal end of the shaft. In a presently preferred alternate embodiment illustrated in

FIG. 3C

, in which like elements are designated with like reference numerals, the apertures can be arranged in a pattern of a varying density, such as in a gradient, of round holes


41


, which can be formed such as by laser cutting, helically arranged so as to provide an optical fiber shaft that is torqueable and pushable at the proximal end, yet soft and flexible at the distal end. In another presently preferred aspect, the outer surface of the reinforcing tube can also be formed to have a taper (not shown) at the point where the helical apertures are formed in the reinforcing tube, such as by grinding or laser cutting, particularly at a distal portion of the reinforcing tube, to provide an optical fiber shaft that is torqueable and pushable at the proximal end, yet soft and flexible at the distal end.




In a further aspect of the invention illustrated in

FIG. 4A

, all or a portion of the shaft


42


can be formed with alternating laterally arranged apertures or cuts, slits, channels or grooves


44


,


46


in the reinforcement tube to produce a composite shaft that has desired flexibility in a specific area of the shaft. Such a configuration can include variable width and depth of the apertures


44


,


46


in order to vary the flexibility, torqueability and pushability of the shaft. In a presently preferred alternate embodiment illustrated in

FIG. 4B

, the laterally arranged apertures can be formed as groups


44


′,


46


′ of round apertures


47


, formed such as by laser cutting, for example.




As described above, at least one coaxial outer covering or sheath


24


is also provided over at least a portion of the optical fiber and the reinforcing tube, for providing desired variations in stiffness along at least a portion of the length of the shaft. Such an outer sheath is currently preferably a heat shrink polymer, such as polyethylene, PTFE, PEEK, PET or PPS, for example, although other similar heat shrink polymers may also be suitable. Alternatively, the outer sheath can be a metal tube, such as a metal tube formed from a nickel titanium alloy, for example, that can be bonded adhesively over the outer surface of the optical fiber, such as by cyanoacrylate adhesive.




The one or more coaxial layers can be formed of heat shrink polymeric material, such as polyethylene, polytetrafluoroethylene (PTFE) polyethylene terephthalate (PET), polyetherethylketone (PEEK), polyphenylenesulfide (PPS), or any of a variety of other polymers which can be fabricated into a structure and necked or shrunk over a shaft, or can be formed of metal. While the invention can effectively use tubes which are placed over the exterior of the optical fiber shaft and then heat shrunk or bonded by adhesive to the fiber, it is also contemplated that the shaft can be reinforced by other longitudinally extending additional structures with varying cross sections for certain specific applications.




The heat shrink tubing is placed on the fiber, and then heat can be applied to the heat shrink tubing, resulting in shrinkage of the heat shrink tubing to encapsulate the fiber. The structure formed by the apertures in the surface of the reinforcing tube, in combination with the distal taper of the reinforcing tube and outer coaxial sheath, allows the proximal part of the composite shaft to be relatively stiff, and the distal tip to be flexible and soft. A variety of other techniques can be used within the scope of the invention to accomplish the variable stiffness of the optical fiber shaft.




For neurovascular use, the overall length of an optical fiber pusher can be, for example, from 100 to 300 cm, with the outer diameter being less than about 1 French (0.0135 inch). For peripheral use, the overall length of the catheter can be, for example, from 100 to 300 cm, with the outer diameter of the distal 25 to 45 cm being less than about 5 French (0.063 inch), and the outer diameter of the proximal 100 cm being less than about 6 French (0.075 inch). For cardiovascular use, the overall length of the catheter can be, for example, from 150 to 175 cm, with the outer diameter of the distal 25 cm being less than about 3 French (0.038 inch), and the outer diameter of the proximal 100 cm being less than about 4 French (0.050 inch). These dimensions are approximate, and in practical terms, depend upon sizes of shrink tubing that are commercially available.




In practice, optical fibers used for micro-coil delivery and the like are approximately 0.003 to approximately 0.014 inches in diameter, with the outer buffer comprising a layer of approximately 0.0005 to 0.002 inches in thickness of a polymer over a thin layer of cladding used to limit the dissipation of light out of the shaft. In one presently preferred embodiment, the outer buffer can be centerless ground to provide a variable thickness characteristic and the fiber can be manufactured with a thicker than normal buffer to facilitate grinding of the buffer to provide a desired bending stiffness either with or without additional layers of stiffening polymers over the outer surface of the fiber.




In one example of the method of manufacturing the variable stiffness optical fiber shaft of the invention, the shaft can be assembled by sliding and centering a polyethylene coaxial heat shrink tube, which can be, for example, 200 cm in length, over a optical fiber, which can be, for example, 205 cm long. The ends of the optical fiber are then clamped, and tension is applied to keep the optical fiber taut. The proximal end of the polyethylene heat shrink tube is placed into the working area of a heat gun, although other means of controllably heating the heat shrink polymeric sheath may be used. The temperature of the polyethylene heat shrink tube is heated to approximately 650 F, and the rest of the heat shrink tube is heated by sliding the heat gun along the axis of the heat shrink tube at about three inches per second, for example, until the heat gun has traveled the length of the polymeric material and the polyethylene has encapsulated the optical fiber. This method is repeated for 150 cm and 100 cm lengths of polymeric tubing, and any further heat shrink tubing to be used for varying the stiffness of the optical fiber shaft, until the outside diameter of the shaft is built up to the desired dimensions to yield the desired degrees of stiffness.




Those skilled in the art will recognize that a variety of polymers, including those filled with reinforcing fibers or other material may be used to reinforce an optical fiber so that it can be more effectively used as a pusher within a catheter lumen or as a free therapeutic member. For example, the characteristics of the materials to be used may be optimized by use of abutting adjacent covers of different materials against one another longitudinally in end to end fashion to thus provide a constant outer diameter. In such a construction, the outer sheath is joined by heat and/or pressure or adhering bonded sections surrounding specific portions of the optical fiber, to provide a smooth overall exterior to the finished composite shaft.




It will be apparent from the foregoing that while particular forms of the invention have been illustrated and described, various modifications can be made without departing from the spirit and scope of the invention. For example, some of the various techniques of the invention can be advantageously combined for certain applications, while others are effectively met by only one aspect of the embodiments discussed. Accordingly, it is not intended that the invention be limited, except as by the appended claims.



Claims
  • 1. A variable stiffness optical fiber shaft for use in interventional vascular therapy, comprising:an optical fiber having a proximal end and a distal end; a reinforcing tube bonded to the optical fiber, the optical fiber extending through said reinforcing tube, and said reinforcing tube having an outer surface including a plurality of apertures to provide variations in stiffness along the length of the optical fiber.
  • 2. The variable stiffness optical fiber shaft of claim 1, further comprising at least one outer coaxial sheath over at least a portion of said optical fiber and said reinforcing tube.
  • 3. The variable stiffness optical fiber shaft of claim 2, wherein said outer coaxial sheath is formed from a material selected from the group consisting of a polymer, metal, or a combination thereof.
  • 4. The variable stiffness optical fiber shaft of claim 3, wherein said polymer comprises heat shrink polymeric material.
  • 5. The variable stiffness optical fiber shaft of claim 4, wherein said polymer is selected from the group consisting of polyethylene, polytetrafluoroethylene, polyethylene terephthalate, polyetherethylketone, and polyphenylenesulfide.
  • 6. The variable stiffness optical fiber shaft of claim 1, wherein said plurality of apertures comprise axial slits formed in the surface of the reinforcing tube.
  • 7. The variable stiffness optical fiber shaft of claim 1, wherein the apertures can be formed as helical slits in the surface of the reinforcing tube.
  • 8. The variable stiffness optical fiber shaft of claim 1, wherein the outer surface of the reinforcing tube is tapered along its length.
  • 9. The variable stiffness optical fiber shaft of claim 8, wherein the outer surface of the reinforcing tube is tapered at the point where the apertures are formed in the reinforcing tube.
  • 10. The variable stiffness optical fiber shaft of claim 9, wherein the outer surface of the reinforcing tube is tapered at a distal portion of the reinforcing tube, whereby said optical fiber is torqueable and pushable at the proximal end, yet soft and flexible at the distal end.
  • 11. The variable stiffness optical fiber shaft of claim 1, wherein the apertures comprise a plurality of lateral slits formed in the surface of the reinforcing tube.
  • 12. A variable stiffness optical fiber shaft for use in interventional vascular therapy, comprising:an optical fiber having a proximal end and a distal end; a reinforcing tube attached to the optical fiber, the optical fiber extending through said reinforcing tube, and said reinforcing tube having an outer surface including a plurality of apertures extending in a direction between said proximal and distal ends of said optical fiber; and at least one outer coaxial sheath bonded over at least a portion of said optical fiber and said reinforcing tube, to provide variations in stiffness along the length of the optical fiber.
  • 13. The variable stiffness optical fiber shaft of claim 12, wherein said plurality of apertures comprise axial slits formed in the surface of the reinforcing tube.
  • 14. The variable stiffness optical fiber shaft of claim 12, wherein the apertures can be formed as helical slits in the surface of the reinforcing tube.
  • 15. The variable stiffness optical fiber shaft of claim 12, wherein the outer surface of the reinforcing tube is tapered along its length.
  • 16. The variable stiffness optical fiber shaft of claim 15, wherein the outer surface of the reinforcing tube is tapered at the point where the apertures are formed in the reinforcing tube.
  • 17. The variable stiffness optical fiber shaft of claim 16, wherein the outer surface of the reinforcing tube is tapered at a distal portion of the reinforcing tube, whereby said optical fiber is torqueable and pushable at the proximal end, yet soft and flexible at the distal end.
  • 18. The variable stiffness optical fiber shaft of claim 12, wherein the apertures comprise a plurality of lateral slits formed in the surface of the reinforcing tube.
  • 19. The variable stiffness optical fiber shaft of claim 12, wherein said outer coaxial sheath is formed from a material selected from the group consisting of a polymer, metal, or a combination thereof.
  • 20. The variable stiffness optical fiber shaft of claim 19, wherein said polymer comprises heat shrinkable polymeric material.
  • 21. The variable stiffness optical fiber shaft of claim 20, wherein said polymer is selected from the group consisting of polyethylene, polytetrafluoroethylene, polyethylene terephthalate, polyetherethylketone, and polyphenylenesulfide.
US Referenced Citations (252)
Number Name Date Kind
679671 Hannigan Jul 1901 A
1341052 Gale May 1920 A
1621159 Evans Mar 1927 A
1667730 Green May 1928 A
2078182 MacFarland Apr 1937 A
2549335 Rahthus Apr 1951 A
3334629 Cohn Aug 1967 A
3417746 Moore et al. Dec 1968 A
3428611 Brotherton et al. Feb 1969 A
3572891 Longenecker Mar 1971 A
3649224 Anderson et al. Mar 1972 A
3670721 Fukami et al. Jun 1972 A
3788304 Takahashi Jan 1974 A
3868956 Alfidi et al. Mar 1975 A
4176662 Frazer Dec 1979 A
4241979 Gagen et al. Dec 1980 A
4248910 Pedain et al. Feb 1981 A
4327734 White, Jr. May 1982 A
4341218 Ü Jul 1982 A
4402319 Handa et al. Sep 1983 A
4441495 Hicswa Apr 1984 A
4450246 Jachimowicz May 1984 A
4473665 Martini-Vvedensky et al. Sep 1984 A
4494531 Gianturco Jan 1985 A
4503569 Dotter Mar 1985 A
4512338 Balko et al. Apr 1985 A
4522195 Schiff Jun 1985 A
4545367 Tucci Oct 1985 A
4585000 Hershenson Apr 1986 A
4638803 Rand Jan 1987 A
RE32348 Pevsner Feb 1987 E
4655771 Wallsten Apr 1987 A
4690175 Ouchi et al. Sep 1987 A
4692139 Stiles Sep 1987 A
4718907 Karwoski et al. Jan 1988 A
4748986 Morrison et al. Jun 1988 A
4753222 Morishita Jun 1988 A
4753223 Bremer Jun 1988 A
4768507 Fischell et al. Sep 1988 A
4791913 Maloney Dec 1988 A
4795458 Regan Jan 1989 A
4800882 Gianturco Jan 1989 A
4808164 Hess Feb 1989 A
4813925 Anderson, Jr. et al. Mar 1989 A
4820298 Leveen et al. Apr 1989 A
4830003 Wolff et al. May 1989 A
4850960 Grayzel Jul 1989 A
4856516 Hillstead Aug 1989 A
4873978 Ginsburg Oct 1989 A
4884579 Engelson Dec 1989 A
4902129 Siegmund et al. Feb 1990 A
4904048 Sogawa et al. Feb 1990 A
4913701 Tower Apr 1990 A
4944746 Iwata et al. Jul 1990 A
4954126 Wallsten Sep 1990 A
4957479 Roemer Sep 1990 A
4957501 Lahille et al. Sep 1990 A
4969709 Sogawa et al. Nov 1990 A
4969890 Sugita et al. Nov 1990 A
4976690 Solar et al. Dec 1990 A
4984581 Stice Jan 1991 A
4990155 Wilkoff Feb 1991 A
4994069 Ritchart et al. Feb 1991 A
5002556 Ishida et al. Mar 1991 A
5026377 Burton et al. Jun 1991 A
5034001 Garrison et al. Jul 1991 A
5037404 Gold et al. Aug 1991 A
5037427 Harada et al. Aug 1991 A
5041084 DeVries et al. Aug 1991 A
5055101 McCoy Oct 1991 A
5064435 Porter Nov 1991 A
5071407 Termin et al. Dec 1991 A
5089005 Harada Feb 1992 A
5100429 Sinofsky et al. Mar 1992 A
5104404 Wolff Apr 1992 A
5108407 Geremia et al. Apr 1992 A
5122136 Guglielmi et al. Jun 1992 A
5133364 Palermo et al. Jul 1992 A
5133731 Butler et al. Jul 1992 A
5133732 Wiktor Jul 1992 A
5135517 McCoy Aug 1992 A
5141502 Macaluso, Jr. Aug 1992 A
5143085 Wilson Sep 1992 A
5147370 McNamara et al. Sep 1992 A
5151105 Kwan-Gett Sep 1992 A
5151152 Kaeufe et al. Sep 1992 A
5160341 Brenneman et al. Nov 1992 A
5160674 Colton et al. Nov 1992 A
5170801 Casper et al. Dec 1992 A
5171233 Amplatz et al. Dec 1992 A
5176625 Brisson Jan 1993 A
5176661 Evard et al. Jan 1993 A
5181921 Makita et al. Jan 1993 A
5183085 Timmermans Feb 1993 A
5184627 de Toledo Feb 1993 A
5186992 Kite, III Feb 1993 A
5192290 Hilal Mar 1993 A
5197978 Hess Mar 1993 A
5203772 Hammerslag et al. Apr 1993 A
5211658 Clouse May 1993 A
5217440 Frassica Jun 1993 A
5217484 Marks Jun 1993 A
5222969 Gillis Jun 1993 A
5222970 Reeves Jun 1993 A
5224953 Morgentaler Jul 1993 A
5226911 Chee et al. Jul 1993 A
5228453 Sepetka Jul 1993 A
5230348 Ishibe et al. Jul 1993 A
5234456 Silvestrini Aug 1993 A
5250071 Palermo Oct 1993 A
5258042 Mehta Nov 1993 A
5261916 Engelson Nov 1993 A
5266608 Katz et al. Nov 1993 A
5304194 Chee et al. Apr 1994 A
5308342 Sepetka et al. May 1994 A
5312415 Palermo May 1994 A
5336205 Zenzen et al. Aug 1994 A
5342387 Summers Aug 1994 A
5350397 Palermo et al. Sep 1994 A
5354295 Guglielmi et al. Oct 1994 A
5354309 Schnepp-Pesch et al. Oct 1994 A
5358493 Schweich, Jr. et al. Oct 1994 A
5360835 Sato et al. Nov 1994 A
5366442 Wang et al. Nov 1994 A
5372587 Hammerslag et al. Dec 1994 A
5378236 Seifert Jan 1995 A
5382259 Phelps et al. Jan 1995 A
5409453 Lundquist et al. Apr 1995 A
5411475 Atala et al. May 1995 A
5413597 Krajicek May 1995 A
5423773 Jimenez Jun 1995 A
5423829 Pham et al. Jun 1995 A
5425723 James Jun 1995 A
5425806 Doolan et al. Jun 1995 A
5437632 Engelson Aug 1995 A
5441516 Wang et al. Aug 1995 A
5443478 Purdy Aug 1995 A
5443498 Fontaine Aug 1995 A
5472017 Kovalcheck Dec 1995 A
5480382 Hammerslag et al. Jan 1996 A
5484424 Cottenceau et al. Jan 1996 A
5499973 Saab Mar 1996 A
5507769 Marin et al. Apr 1996 A
5507995 Schweich, Jr. et al. Apr 1996 A
5514128 Hillsman et al. May 1996 A
5514176 Bosley, Jr. May 1996 A
5522836 Palermo Jun 1996 A
5525334 Ito et al. Jun 1996 A
5531685 Hemmer et al. Jul 1996 A
5531716 Luzio et al. Jul 1996 A
5533985 Wang Jul 1996 A
5536235 Yabe et al. Jul 1996 A
5540680 Guglielmi et al. Jul 1996 A
5540712 Kleshinski et al. Jul 1996 A
5540713 Schneff-Pesch et al. Jul 1996 A
5545210 Hess et al. Aug 1996 A
5549109 Samson et al. Aug 1996 A
5549624 Mirigian et al. Aug 1996 A
5554181 Das Sep 1996 A
5562641 Flomenblit et al. Oct 1996 A
5562698 Parker Oct 1996 A
5569245 Guglielmi et al. Oct 1996 A
5571848 Mortensen et al. Nov 1996 A
5578074 Mirigian Nov 1996 A
5582619 Ken Dec 1996 A
5601593 Freitag Feb 1997 A
5603991 Kupiecki et al. Feb 1997 A
5605162 Mirzaee et al. Feb 1997 A
5607445 Summers Mar 1997 A
5614204 Cochrum Mar 1997 A
5622665 Wang Apr 1997 A
5624461 Mariant Apr 1997 A
5624685 Takahashi et al. Apr 1997 A
5636642 Palermo Jun 1997 A
5637086 Ferguson et al. Jun 1997 A
5637113 Tartaglia et al. Jun 1997 A
5638827 Palmer et al. Jun 1997 A
5639277 Mariant et al. Jun 1997 A
5643251 Hillsman et al. Jul 1997 A
5643254 Scheldrup et al. Jul 1997 A
5645558 Horton Jul 1997 A
5645564 Northrup et al. Jul 1997 A
5649909 Cornelius Jul 1997 A
5649949 Wallace et al. Jul 1997 A
5653691 Rupp et al. Aug 1997 A
5660692 Nesburn et al. Aug 1997 A
5662621 Lafontaine Sep 1997 A
5662622 Gore et al. Sep 1997 A
5662712 Pathak et al. Sep 1997 A
5666968 Imran et al. Sep 1997 A
5667522 Flomenblit et al. Sep 1997 A
5669924 Shaknovich Sep 1997 A
5670161 Healy et al. Sep 1997 A
5676697 McDonald Oct 1997 A
5685480 Evans et al. Nov 1997 A
5690643 Wijay Nov 1997 A
5690666 Berenstein et al. Nov 1997 A
5690671 McGurk et al. Nov 1997 A
5693086 Goicoechea et al. Dec 1997 A
5695111 Nanis et al. Dec 1997 A
5695482 Kaldany Dec 1997 A
5695517 Marin et al. Dec 1997 A
5695518 Laerum Dec 1997 A
5700253 Parker Dec 1997 A
5702361 Evans et al. Dec 1997 A
5702414 Richter et al. Dec 1997 A
5709704 Nott et al. Jan 1998 A
5711909 Gore et al. Jan 1998 A
5716365 Goicoechea et al. Feb 1998 A
5716410 Wang et al. Feb 1998 A
5718711 Berenstein et al. Feb 1998 A
5722989 Fitch et al. Mar 1998 A
5723004 Dereume et al. Mar 1998 A
5725546 Samson Mar 1998 A
5725568 Hastings Mar 1998 A
5733294 Forber et al.. Mar 1998 A
5733329 Wallace et al. Mar 1998 A
5733400 Gore et al. Mar 1998 A
5735816 Lieber et al. Apr 1998 A
5738666 Watson et al. Apr 1998 A
5741323 Pathak et al. Apr 1998 A
5741325 Chaikof et al. Apr 1998 A
5743905 Eder et al. Apr 1998 A
5746765 Kleshinski et al. May 1998 A
5746769 Ton et al. May 1998 A
5749837 Palermo et al. May 1998 A
5749849 Engelson May 1998 A
5749894 Engelson May 1998 A
5749921 Lenker et al. May 1998 A
5755773 Evans et al. May 1998 A
5759173 Preissman et al. Jun 1998 A
5766151 Valley et al. Jun 1998 A
5766167 Eggers et al. Jun 1998 A
5769796 Palermo et al. Jun 1998 A
5769828 Jonkman Jun 1998 A
5782809 Umeno et al. Jul 1998 A
5788626 Thompson Aug 1998 A
5788653 Lorenzo Aug 1998 A
5792124 Horrigan et al. Aug 1998 A
5797842 Plumares et al. Aug 1998 A
5797920 Kim Aug 1998 A
5797957 Palmer et al. Aug 1998 A
5800445 Palermo et al. Sep 1998 A
5800508 Goicoechea et al. Sep 1998 A
5807354 Kenda Sep 1998 A
5807398 Shaknovich Sep 1998 A
5814016 Valley et al. Sep 1998 A
5814062 Septka et al. Sep 1998 A
5817126 Imran Oct 1998 A
5817152 Birdsall et al. Oct 1998 A
5830209 Savage et al. Nov 1998 A
6074374 Fulton Jun 2000 A
Foreign Referenced Citations (7)
Number Date Country
680 041 Jun 1992 CH
4102550 Aug 1991 DE
0 183 372 Jun 1986 EP
0 382014 Aug 1990 EP
592.182 Jul 1925 FR
2 066 839 Jul 1981 GB
WO 8702473 Apr 1987 WO
Non-Patent Literature Citations (18)
Entry
Christos A. Athanasoulis, M.D., The New England Journal Of Medicine, May 15, 1980, “Therapeutic Applications Of Angiography” pp. 1117-1125 (1 Of 2).
Christos A. Athanasoulis, M.D., The New England Journal Of Medicine, May 22, 1980, “Therapeutic Applications Of Angiography” pp. 1174-1179 (2 Of 2).
Alex Berenstein, M.D. and Irvin I. Kricheff, M.D., “Catheter And Material Selection For Transarterial Embolization: Technical Considerations” Radiology, Sep. 1979; pp. 631-639.
O.A. Battista, et al. Journal Of Applied Polymer Science 1967 “Colloidal Macromolecularphenomena. Part II. Novel Microcrystals of Polymers” pp. 481-498.
Sadek K. Hilal, M.D. et al. Journal Of Neurological Surgery “Therapeutic Percutaneous Embolization For Extra-Axial Vascular Lesions Of The Head, Neck And Spine”Sep., 1975; pp. 275-287.
Stephen L. Kaufman, M.D. et al. Investigative Radiology, May-Jun. 1978, “Transcatheter Embolization With Microfibrillar Collagen In Swine”, pp. 200-204.
Ashok J. Kumar, et al., Journal Of Neuroradiology (1982) “Preoperative Embolization Of Hypervascular Head And Neck Neoplasms Using Microfibrillar Collagen”, pp. 163-168.
Richard E. Latchaw, M.D. et al., Radiology (1979) “Polyvinyl Foam Embolization Of Vascular And Neoplastic Lesions Of The Head, Neck And Spine” pp. 669-679.
Stewart R. Reuter, M.D. et al. American Journal Of Radiology, Sep. 1975, “Selective Arterial Embolization For Control Of Massive Upper Gastrointestinal Bleeding” pp. 119-126.
Glenn H. Roberson, et al., American Journal Of Radiology, Oct. 1979, “Therapeutic Embolization Of Juvenile Angiofibroma” pp. 657-663.
Sidney Wallace, M.D. et al., Cancer; Oct. 1979, “Arterial Occlusion Of Pelvic Bone Tumors”, pp. 322-325 & 661-663.
“Mechanical Devices For Arterial Occlusion” By C. Gianturco, M.D., et al., Jul. 1975, pp. 428-435.
“Therapeutic Vascular Occlusion Utilizing Steel Coil Technique: Clinical Applications” By Sidney Wallace, et al., AM J. Roentgenol (1976); pp. 381-387.
“Transcatheter Intravascular Coil Occlusion Of Experimental Arteriovenous Fistulas”, By James H. Anderson, et al., AM. J. Roentgenol, Nov. 1977, pp. 795-798.
“‘Mini’Gianturco Stainless Steel Coils For Transcatheter Vascular Occlusion” By James H. Anderson, et al., From The Department Of Diagnostic Radiology At The University Of Texas System Cancer Center, Aug. 1978, pp. 301-303.
“A New Improved Coil For Tapered-Tip Catheter For Arterial Occlusion” By Vincent P. Chuang, M.D., et al., May 1980. pp. 507-509.
International Search Report Dated Jun. 10, 1999.
Copy Of Saint Côme Advertisement For Crisco Endoprosthesis For Microaneurysm Embolization.