Vaso-occlusive coil delivery system

The art of the invention generally relates to systems and supply devices for implanting vascular occlusion devices to achieve embolization or occlusion in blood vessels of human or veterinary patients.

Vascular closure devices or implants are used for a variety of reasons, including the treatment of intravascular aneurysms. A typical vascular closure device takes the form of a flexible spiral wound coil formed by winding a platinum (or platinum alloy) wire strand around a first mandrel. The relative stiffness of the coil will depend, in particular, on its composition, the diameter of the wire strands, the diameter of the first mandrel and the pitch of the first mandrel. The coil is then wrapped around a larger second mandrel and heat treated to give it a second shape. For example, U.S. Pat. No. 4,994,069 issued to Ritchart et al., When stretched for the lumen-mediated placement of the delivery catheter, forms a linear, spiral first shape and is released from the delivery catheter. Disclosed is a vascular closure coil that bends and bends into a second shape when placed in a vascular structure.

To carry the vascular closure device to a desired site within the vascular structure, such as an aneurysm, a small external delivery catheter or microcatheter may first be placed at that site using an operable guide wire. Well known. Typically, the distal end of the microcatheter is a preformed bend selected by either the physician or the manufacturer, depending on the specific biostructure of the patient, eg, 45 °, 90 °. , "J-shaped", "S-shaped" or other bent shape, and as a result, when the guide wire is pulled out, one or more vascular closure coils are desired to be released within the aneurysm. It will stay in position. The feed or "push" wire then travels through the microcatheter until the vascular closure coil attached to its distal end extends from the distal end opening of the microcatheter into the aneurysm. The vascular closure device is then released or "separated" from the end push wire, which is pulled back through the catheter. Another closure device can then be pushed through the catheter and released at the same site, depending on the patient's specific needs.

One of the known methods of releasing the vascular closure coil from the end of the indentation wire is to use an electrolyzable joint that is a small exposed section or separation area located along the distal end of the indentation wire. It is due to doing. The separation region is typically formed of stainless steel and is located immediately proximal to the vascular closure device. Electrolytically separable connections are prone to electrolysis and decompose when the indentation wire is charged in the presence of an ionic solution such as blood or other body fluid. Thus, when the separation area exits the distal end of the catheter and is exposed to the blood pool of the patient's blood vessels, the current applied to the conductive indentation wire is removed from the electrode attached to the patient's skin. A circuit is formed at the site with a conductive needle inserted through the skin, and the separated area collapses due to electrolysis.

A known problem with current blockage separation schemes is that the coupling between the delivery wire and the blockage member (eg, the coil) can be relatively long and stiff. For example, various intermediate coils and PET couplings between the distal end of the delivery wire and the closing coil add rigidity to the overall structure. The rigid bond between the delivery wire and the closure member makes it difficult to accurately position the feed system in the desired position. For example, the rigid portion of the delivery wire or delivery wire / coil joint can cause the preformed microcatheter to bounce or recoil from the aneurysm upon release of the coil.

Another known problem with one current blockage isolation device is the use of separate return or ground electrodes to complete the electrical circuit between the external power supply and the coil separable by electrolysis. .. This separate return or ground electrode can be a patch placed on the patient's body or a needle inserted into the patient's groin. However, the use of separate returns or ground electrodes causes variations in the separation time of the closed coil. This variation is caused by the different tissue types and densities that exist between the closure device and the return electrode. In addition, some patients may feel uncomfortable or painful due to the grounding needle placed in the patient's groin.

In one embodiment, the closed coil feeding system comprises a closed coil having multiple windings, the closed coil having a proximal end and a distal end, the proximal end of the closed coil having a plurality of spaced openings. Includes open pitched windings. The system also includes a delivery wire adapter with a proximal end and a distal end so that the distal end of this adapter is coupled between adjacent spaced windings of the proximal end of the closure coil. It has a plurality of configured fingerers. The system further includes a delivery wire secured to the proximal end of the delivery wire adapter, the delivery wire comprising a sacrificial detachment region in part thereof. The sacrificial separation region can be broken or otherwise decomposed in response to electrical energy (eg, electrolytic separation region) or thermal energy (eg, thermal separation region).

According to yet another embodiment, a delivery wire adapter having a proximal end and a distal end is used to secure the delivery wire to the closing coil, wherein the distal end of the delivery wire adapter is closed. Disclosed is a method comprising a plurality of finger-like portions configured to be coupled between adjacent spaced winding portions at the proximal end of the coil. This method involves forming a spaced winding at the proximal end of the closure coil and rotating at least one of the closure coil and delivery wire adapter around multiple fingerpieces to rotate the closure coil and delivery. Includes a step of forming a coupling with the wire adapter. The coupling portion between the closing coil and the delivery wire adapter may be fixed by the use of an adhesive such as epoxy. The delivery wire is then secured to the proximal end of the delivery wire adapter.

According to another embodiment, the closed coil feeding device comprises a closed coil having a plurality of windings, the proximal end thereof having a plurality of spaced windings. The feeding device also includes a delivery wire assembly having a proximal tubular portion and a distal coil portion, and at least partially penetrating lumens. The delivery wire forming the first conductive path extends through the lumen from the proximal end of the delivery wire assembly to a position distal to the distal coil portion. The distal extension contains the electrolytic separation region. The delivery wire assembly further includes a second conductive path formed by a proximal tubular portion and a distal coil portion. The feed device further includes a delivery wire adapter with a proximal end and a distal end so that the distal end of this adapter is coupled between adjacent spaced windings of the proximal end of the closing coil. It includes a plurality of configured finger-shaped portions. The proximal end of the delivery wire adapter is secured to the distal portion of the delivery wire.

In yet another embodiment, the system for supplying the closure coil comprises a delivery catheter having proximal and distal ends and lumens extending between the proximal and distal ends. The delivery catheter may include, for example, a microcatheter. The system includes a delivery wire assembly having a proximal end and a distal end, which delivery wire assembly includes a proximal tubular portion and a distal coil portion. The delivery wire, which is configured as part of the delivery wire assembly, forms a first conductive path and extends from the proximal end of the delivery wire assembly to a position distal to the distal coil portion, which is distal. A portion extending distal to the coil portion has an electrolytic separation region. The delivery wire assembly further includes a second conductive path formed by a proximal tubular portion and a distal coil portion. The second conductive path is electrically insulated from the first conductive path.

In one embodiment, the system comprises a closure coil with multiple windings, the closure coil having a proximal end and a distal end, the proximal end of the closure coil being a plurality of spaced windings. Including the wire part. The system further includes a delivery wire adapter with a proximal end and a distal end, the distal end of the delivery wire adapter coupling between adjacent spaced windings of the proximal end of the closing coil. It is provided with a plurality of finger-shaped portions configured as described above. The proximal end of the delivery wire adapter is configured to attach to the distal portion of the delivery wire. The system includes a power supply configured to electrically connect the first and second conductive paths. The power supply supplies an electric current to the delivery wire and the electrolytic sacrificial link contained therein, which is electrolyzed in the presence of body fluid (or wash solution).

<figref num="1">FIG. 1 shows a closed coil supply system according to an embodiment.</figref><figref num="2">FIG. 2 is a plan view of the transmission wire adapter according to the embodiment.</figref><figref num="3">FIG. 3 shows a delivery wire secured to the distal end of the delivery wire adapter of the type shown in FIG. The distal end of the delivery wire adapter is secured to the proximal end of the closing coil.</figref><figref num="4">FIG. 4 shows an alternative embodiment. As shown in FIG. 4, the delivery wire is secured to the proximal end of the delivery wire adapter of the type shown in FIG. The distal end of the delivery wire adapter is secured to the proximal end of the closing coil. In this embodiment. An outer retaining sleeve is arranged around the outer circumference of a portion of the closing coil.</figref><figref num="5">FIG. 5 shows a cross-sectional view of the delivery wire assembly according to the embodiment.</figref><figref num="6">FIG. 6A shows a cross-sectional view of the coupling portion between the distal end of the delivery wire assembly and the closing coil according to one embodiment. FIG. 6B shows a vertical cross section (relative to FIG. 6A) of the junction between the distal end of the delivery wire assembly and the closing coil.</figref><figref num="7">FIG. 7A shows a cross-sectional view of the closed coil along the AA line of FIG. 6A. FIG. 7B shows a detailed view of region B shown in FIG. 6B. FIG. 7C shows a detailed view of region C shown in FIG. 6A.</figref><figref num="8">FIG. 8 shows a closed coil in the natural state mode in which an example of an exemplary second configuration is shown.</figref><figref num="9">FIG. 9A shows multiple delivery wire adapters formed on a single substrate. FIG. 9B shows a delivery wire adapter according to an embodiment.</figref><figref num="10">FIG. 10 shows the separation of the closing coil from the delivery wire assembly into the aneurysm according to one embodiment.</figref>

FIG. 1 shows a closed coil supply system 10 according to an embodiment. This system 10 contains a number of subsystems or subsystems. These include a delivery catheter 100, a delivery wire assembly 200, a closure coil 300 and a power supply 400. The delivery catheter 100 includes a proximal end 102, a distal end 104, and a lumen 106 extending between the proximal end 102 and the distal end 104. The lumen 106 of the delivery catheter 100 is sized to provide axial movement of the delivery wire assembly 200. Further, the lumen 106 is sized according to the passage of the guide wire (not shown). The guide wire can optionally be used to properly guide the delivery catheter 100 to a suitable supply site. The delivery catheter 100 can include a stainless steel flat wire braided shaft configuration encapsulated or surrounded by a polymeric coating. For example, HYDROLENE® is one of the exemplary polymeric coatings that can be used to coat the outer portion of the delivery catheter 100. Of course, the system 10 is not limited to the delivery catheter 100 of any particular structure or type, and other structures known to those of skill in the art can also be used for the delivery catheter 100.

The inner lumen 106 is preferably covered with a lubricating coating such as PTFE to reduce the frictional force between the device moving axially within the lumen 106 and the delivery catheter 100. The delivery catheter 100 may include any one or more marker bands 108 formed from an x-ray opaque material, which uses imaging techniques (eg, x-ray fluoroscopic images) to vascularize the patient. It can be used to locate the delivery catheter 100 in the system. The length of the delivery catheter 100 can be varied depending on the specific application, but is generally about 150 cm in length. Of course, delivery catheters 100 of other lengths can also be used with the system 10 described herein.

The delivery catheter 100 can include a straight distal end 104, as shown in FIG. Alternatively, the distal end 106 can be preformed into a particular geometry or orientation. For example, the distal end 104 can be shaped into a "C" shape, an "S" shape, a "J" shape, a 45 ° bend shape, and a 90 ° bend shape. The dimensions of the lumen 106 can vary depending on the dimensions of the delivery wire assembly 200 and the closure coil 300, but in general, the diameter lumen 106 of the delivery catheter 100 (ID (inner diameter) of the delivery catheter 100) is approximately. Less than 0.02 inch. In some embodiments, the delivery catheter 100 is known to those of skill in the art as a microcatheter. Although not shown in FIG. 1, the delivery catheter 100 can be used with a separate guide catheter (not shown) that helps guide the delivery catheter 100 to an appropriate location within the patient's blood vessels.

Further referring to FIG. 1, the system 10 includes a delivery wire assembly 200 configured for axial movement within the lumen 106 of the delivery catheter 100. The delivery wire assembly 200 generally includes a proximal end 202 and a distal end 204. In one embodiment, the delivery wire assembly 200 includes a proximal tubular portion 206 and a distal coil portion 208. The proximal tubular portion 206 can be formed, for example, from a stainless steel hypotube. As described in more detail herein, the distal coil portion 208 can be joined to the proximal tubular portion 206 in an end-to-end arrangement. The sending wire assembly 200 further includes a sending wire 210, which extends from the proximal end 202 of the sending wire assembly 200 to a position distal to the distal end 204 of the sending wire assembly 200. The delivery wire 210 is located within a lumen 212 extending within an inner portion of the delivery wire assembly 200.

The delivery wire 210 is made of a conductive material such as a stainless steel wire. The proximal end 214 (shown in perspective) of the sending wire 210 is electrically connected to an electrical contact 216 located at the proximal end 202 of the sending wire assembly 200. The electrical contacts 216 can be formed from metal solder (eg, gold) configured to couple with the corresponding electrical contacts (not shown) of the power supply 400. Part of the delivery wire 210 is preferably covered with an insulating coating 218. The insulating coating 218 can include polyimide. In one embodiment, the delivery wire 210 is coated with an insulating coating 218 over its entire length, except for a small area 220 located in a portion of the delivery wire 210 that extends distal to the distal end 204 of the delivery wire assembly 200. Has been done. This "exposed" portion of the delivery wire 210 forms an electrolytic separation region 220 that dissolves upon application of a current from the power supply 400.

In an alternative embodiment, the sacrificial moiety can be configured to break or dissolve in response to thermal energy instead of the electrolytic separation region 220. For example, the separation region 220 can be formed from a polymer link (eg, a fiber) that melts or melts in response to externally applied thermal energy or heat. The polymer link can be formed from a thermoplastic material (eg, polyethylene) that has a high tensile strength and a suitable melting temperature. The heat-sensitive sacrificial portion may be one that reacts to an electrical resistance heating coil configured to apply to the separation region 220. Such a heating coil operates by generating heat in response to an applied electric current. Alternatively, electromagnetic or RF energy can be used to destroy or dissolve the sacrificial part. U.S. Pat. No. 7,198,613 discloses further details regarding the various thermooperated separation modes.

Further referring to FIG. 1, the distal end 222 of the delivery wire 210 ends in a hook or "J" shape. The closing coil 300 is shown in FIG. 1 in a state of being fixed to the distal end 222 of the delivery wire 210 via the delivery wire adapter 230. The delivery wire adapter 230 includes a proximal end 232 and a distal end 234. The proximal end 232 of the delivery wire adapter 230 includes an opening 236 (as seen in FIG. 2) sized to receive the distal end 222 of the delivery wire 210. At that time, in order to fix the sending wire 210 to the proximal end 232 of the sending wire adapter 230, the hook portion of the sending wire 210 passes through the opening 236. The middle and distal ends 234 of the delivery wire adapter 230 include multiple finger or protrusions 238 (most commonly seen in FIG. 2). The finger-shaped portion 238 provided on the delivery wire adapter 230 is configured to be coupled to the closing coil 300.

In particular, the closure coil 300 includes a proximal end 302, a distal end 304, and a lumen 306 extending between those ends. The closed coil 300 is generally made of a biocompatible metal such as platinum or a platinum alloy (eg, platinum tungsten alloy). The closure coil 300 generally includes a linear configuration (as shown in FIG. 1) when the closure coil 300 is mounted within the delivery catheter 100. When released, the closing coil 300 generally takes a second shape, including a two-dimensional or three-dimensional configuration as shown in FIG. As a matter of course, the system 10 described herein can be used with the closing coil 300 having various configurations, and is not limited to the particular closing coil 300 having a particular size and configuration.

The closed coil 300 includes a plurality of coil windings 308. The coil winding 308 is generally spiral around the central axis arranged along the lumen 306 of the closed coil 300. As seen in FIG. 1, the proximal end 302 of the closed coil 300 comprises a coil winding 308 with a spaced configuration. For example, some proximal coil windings 308 are spaced apart in a spaced configuration (shown by arrow A in FIG. 1). The remaining distal portion of the closure coil 300 may have a spaced (closed pitch) configuration as shown in FIG. Of course, the distal portion of the closure coil 300 can include one or more spaced segments or regions (or the entire closure coil 300 can be an spaced configuration). ). The spaced proximal coil winding 308 provides a threaded-like recess in the joint where the corresponding finger 238 of the delivery wire adapter 230 is attached.

The finger-shaped portion 238 of the sending wire adapter 230 secures the closing coil 300 to the sending wire adapter 230, but adheres to the coupling portion between the sending wire adapter 230 and the coil winding 308 proximal to the closing coil 300. It is desirable to apply agent 240. The adhesive 240 can also cover the joint formed between the distal end 222 of the delivery wire 210 and the proximal end 232 of the delivery wire adapter 230. Adhesive 240 can include an epoxy material that is solidified or cured through heating or UV radiation. For example, Adhesive 240 can include a thermosetting two-part epoxy such as EPO-TEK® 353ND-4 available from Epoxy Technology, Inc., located at Fortune Drive 14 in Bill Rica, Massachusetts. The adhesive 240 encloses the delivery wire adapter 230 and arranges it substantially concentrically with the closing coil 300, and prevents the tangential movement caused by the axial tensile load of the closing coil 300.

Instead of using adhesive 240, adjacent coil windings 308 on any side of the finger 238 can also be joined by laser tack, spot welding or continuous welding. Alternatively, the laser melting of the finger 238 on the coil winding 308 can be used to mechanically couple the delivery wire adapter 230 to the closing coil 300.

Continuing with reference to FIG. 1, the proximal tubular portion 206 and the distal coil portion 208 form the return electrode of the supply system 10. At that time, the delivery wire 210 forms a first conductive path 242 between the electrical contact 216 and the electrolytic separation region 220. The first conductive path 242 can form the anode (+) of the electrolytic circuit when the delivery wire assembly 200 is operably connected to the power supply 400. The second conductive path 244 is formed by a proximal tubular portion 206 and a distal coil portion 208 of the delivery wire assembly 200. The second conductive path 244 is electrically insulated from the first conductive path 242. The second conductive path 244 can form a cathode (-) or a ground electrode of an electric circuit. The electrical contact 246 of the second conductive path 244 can be located at the proximal end of the tubular portion 206. In one embodiment, the tubular portion 206 is part of the second conductive path 244, so that the electrical contact 246 is simply an exposed portion of the tubular portion 206. For example, the proximal portion of the tubular portion 206 adjacent to the electrical contact 216 may be covered with an insulating coating 207 such as polyimide, as shown in FIG. The exposed area of the tubular portion 206 without the insulating coating can form an electrical contact 246. Alternatively, electrical contacts 246, ring electrodes, or other contact and be formed outside of the tubular portion 206 may Rukoto.

The electrical contact 246 is configured to couple with a corresponding electrical contact (not shown) within the power supply 400 when the proximal end 202 of the delivery wire assembly 200 is inserted into the power supply 400. The electrical contact 246 of the second conductive path 244 is, of course, electrically insulated from the electrical contact 216 of the first conductive path 242.

Further referring to FIG. 1, the system 10 includes a power supply 400 for supplying direct current to the delivery wire 210 including the electrolytic separation region 220. In the presence of a conductive fluid (including a physiological solution such as blood or a washing solution such as saline), when the power supply 400 is activated, it enters the circuits in the first conductive path 242 and the second conductive path 244. Current flows. After a few seconds (typically less than about 10 seconds), the sacrificial electrolytic separation region 220 dissolves and the closed coil 300 separates from the delivery wire 210.

The power supply 400, along with the drive circuit 402, will include a built-in energy source such as a battery (eg, two AAA batteries). Drive circuit 402 can include one or more microcontrollers or processors configured to output drive current. The power supply 400 shown in FIG. 1 includes a receptacle 404 configured to accept and couple the proximal end 202 of the delivery wire assembly 200. When the proximal end 202 is inserted into the receptacle 404, the electrical contacts 216,246 provided in the delivery wire assembly 200 are electrically connected to the corresponding contacts (not shown) located in the power supply 400. Visible indicator 406 (eg, LED light) can indicate when the proximal end 202 of the delivery wire assembly 200 is properly inserted into the power supply 400. Another visible indicator 407 can also be activated if the battery needs to be replaced. The power supply 400 typically includes an actuating trigger or button 408 pressed by the user to apply an electric current to the sacrificial electrolytic isolation region 220. Typically, when the actuating trigger 408 is actuated, the drive circuit 402 automatically supplies current until separation occurs. The drive circuit 402 typically operates by applying a nearly constant current (eg, about 1.5 mA).

The power supply 400 may include any detection circuit 410 configured to detect when the closing coil 300 is separated from the delivery wire 210. The detection circuit 410 can identify the separation based on the measured impedance value. The visible indicator 412 can indicate when the power supply 400 is supplying current to the sacrificial electrolytic separation region 220. Another visible indicator 414 can indicate when the closure coil 300 is separated from the delivery wire 210. Upon separation, an acoustic signal (eg, beep) or tactile signal (eg, vibration or buzzer) can be generated instead of the visible indicator 414. The detection circuit 410 can be configured to invalidate the drive circuit 402 when it detects the separation of the closing coil 300.

The power supply 400 may also include another visible indicator 416 that indicates to the operator when the traditional non-bipolar sending wire assembly is inserted into the power supply 400. As mentioned in the background art, conventional devices use a separate return electrode, which typically takes the form of a needle that is inserted into the patient's groin. The power supply 400 is configured to detect the insertion of any of the older non-bipolar sending wire assemblies. Under such circumstances, the visible indicator 416 (eg LED) is lit and the user has a separate return electrode (not shown in FIG. 1) in port 418 where the power supply 400 is located. You will be notified to insert it.

FIG. 2 shows an enlarged side view of the transmission wire adapter 230 according to the embodiment. FIG. 2 shows an opening 236 located at the proximal end 232 of the delivery wire adapter 230. FIG. 2 also shows any opening 250 formed at the distal end 234 of the delivery wire adapter 230. Any opening 250 can be used to secure the distal end 234 of the delivery wire adapter 230 to a stretch resistant member, as will be shown in more detail later. As a matter of course, the opening 250 is completely optional and may be omitted in some embodiments. The openings 236,250 can be smoothed by applying a small drop of adhesive. Alternatively, the inner surface of the openings 236,250 can be chamfered by an electric discharge machine (EDM).

Further, FIG. 2 shows four separate finger portions 238a, 238b, 238c and 238d provided on the transmission wire adapter 230, of which two finger portions 238a, 238b are the transmission wire adapters. It is located on one side of the 230 and the other two finger parts 238c, 238d are located on the other side. In other embodiments, as long as at least one finger-shaped portion 238 is provided on the first side of the sending wire adapter 230 and at least one other finger-shaped portion 238 is provided on the second side opposite the sending wire adapter 230. Can include different quantities of fingertips 238 in the delivery wire adapter 230. For example, in one alternative embodiment, it has two finger portions 238a, 238b on the first side and only one finger portion (either 238c or 238d) on the opposite second side. The sending wire adapter 230 is used. The configuration of this delivery wire adapter 230 is shown, for example, in FIG. 9B (before the excess material is cut off).

The delivery wire adapter 230 can be formed from a biocompatible metal material such as a cured stainless steel 304 alloy. Of course, other metallic materials can also be used. A large number of delivery wire adapters 230 can be formed from a single sheet or substrate, as described in more detail with respect to FIGS. 9A and 9B.

The finished delivery wire adapter 230, as shown in FIG. 2, can have a length of less than 0.03 inches. For example, in one embodiment, the delivery wire adapter 230 can have a length in the range of about 0.02 inches to about 0.03 inches. The thickness of the delivery wire adapter 230 is a function of the thickness of the sheet or substrate on which it is made, but is typically less than 0.003 inches. As a matter of course, it is expected that dimensions other than those explicitly mentioned above are also included in the scope of the present invention.

FIG. 3 shows a coupling portion formed between the delivery wire adapter 230 and the proximal end 302 of the closing coil 300. As can be seen in FIG. 3, finger-shaped portions 238a, 238b, 238c, 238d of the delivery wire adapter 230 are located between adjacent coil windings 308 in the spaced region A. To attach the delivery wire adapter 230 to the proximal end 302 of the closing coil 300, some coil windings 308 (eg 2-3 windings) at the proximal end 302 are pulled axially. , Open so that the configuration is as shown in Fig. 3. One or both of the delivery wire adapter 230 and the closing coil are rotated around the finger portions 238a, 238b, 238c, 238d until the delivery wire adapter 230 progresses to the mounted configuration shown in FIG. At that time, the finger-shaped portions 238a, 238b, 238c, and 238d are joined between the adjacent wound winding portions 208 having an interval. Adhesive 240 is applied over the joint between the finger parts 238a, 238b, 238c, 238d and the coil winding 308 to form a tight and fixed bond between the two components. May be good. FIG. 3 shows beads of adhesive 240 covering the distal end 222 of the delivery wire 210 and the proximal end 232 of the delivery wire adapter 230. The sticky beads 240 may be separated from the adhesive 240 applied over the coil winding 308, or, as an alternative, the two may be combined into one joint, as shown in FIG. It may be.

FIG. 4 shows an alternative embodiment in which any outer sleeve 252 is placed around the perimeter of the coil winding 308 in the spaced region A. The outer sleeve 252 acts as a containment sleeve to prevent movement of the closure coil 300 from the delivery wire adapter 230. The sleeve 252 can also be formed from a metallic material or, if strong enough, a polymer. The sleeve 252 prevents radial displacement of the coil winding 308 when the joint is mounted axially.

FIG. 5 shows a cross-sectional view of the delivery wire assembly 200 according to the embodiment. Similar components of this embodiment are specified with the same reference numerals as those described above with respect to FIGS. 1 to 4. The delivery wire assembly 200 includes a proximal end 202 and a distal end 204 and has a length dimension between about 183 cm and about 187 cm. The delivery wire assembly 200 includes a proximal tubular portion 206 and a distal coil portion 208. The proximal tubular portion 206 may be formed from a 304 stainless steel hypotube having an OD (outer diameter) of 0.0125 inches and an ID (inner diameter) of 0.00825 inches. The length of the hypotube portion can be between about 140 cm and about 150 cm, but other lengths can be used.

As can be seen in FIG. 5, the distal coil portion 208 is joined end-to-end to the distal surface of the proximal tubular portion 206. Joining can be achieved using welding or other joining. The distal coil portion 208 can have a length of about 39 cm to about 41 cm. The distal coil portion 208 can include a 0.0025 inch x 0.006 inch coil. This dimension generally refers to the inner mandrel used to wind a coil wire to form multiple coil windings and is the nominal ID of that coil. One or more coils 310 of the distal coil portion 208 can be formed from an X-ray opaque material (shown as the solid coil 310 of the distal coil portion 208). For example, the distal coil portion 208 includes a portion of the stainless steel coil (eg, 3 mm in length), followed by a portion of the platinum coil (X-ray opaque, also 3 mm in length), and then: It may be followed by a portion of a stainless steel coil (eg, 3 mm in length).

The delivery wire 210 forms a first conductive path 242, ends at an electrical contact 216 at one end, and extends distal to the distal coil portion 208 of the delivery wire assembly 200. The delivery wire 210 is covered with an insulating coating 218 such as polyimide, except for the electrolytic separation region 220 and the proximal portion connected to the electrical contact 216. The delivery wire 210 can have an OD (outer diameter) of about 0.0125 inches. The central coil 260 is attached to the delivery wire 210 in place within the distal coil portion 208. The center coil 260 causes the delivery wire 210 to be properly positioned within the delivery wire assembly 200. The center coil 260 can be joined directly to the delivery wire 210 using an adhesive 240, such as the adhesive described herein. To that end, an adhesive 240 is applied to secure the delivery wire 210 and the central coil 260 to the distal coil portion 208. Adhesive 240 includes EPO-TEK® 353ND-4, described in more detail above.

Continuing with reference to FIG. 5, the outer sleeve 262 or jacket surrounds a portion of the proximal tubular portion 206 and the distal coil portion 208. The outer sleeve 262 covers a joint or joint formed between the proximal tubular portion 206 and the distal coil portion 208. The length of the outer sleeve 262 can range from about 50 cm to about 54 cm. The outer sleeve 262 can be formed from a polyether blockamide plastic material (eg, PEBAX7233 lamination). The outer sleeve 262 can include a laminate of PEBAX and HYDROLENE®. The outer diameter (OD) of the outer sleeve 262 can be less than 0.02 inches, more preferably less than 0.015 inches.

As seen in FIG. 5, a small portion 209 of the distal coil portion 208 is exposed distally beyond the outer sleeve 262. During use, this small portion 209 is exposed to a conductive fluid and acts as a contact for a second conductive path 244 (eg, return or ground path) of the circuit. This distal overhang may be longer than about 0.03 inches. The electrolytic separation region 220 is located approximately 2 millimeters (or less in some embodiments) distal to the distal coil portion 208.

6A and 6B show a vertical cross-sectional view of the closed coil 300 according to one embodiment. In this embodiment, the extension resistance member 270 is fixed to the delivery wire adapter 230 at one end and to the distal end 304 of the closing coil 300 at the other end. Stretch resistance member 270 includes a distal cap or end 272, as is most commonly seen in FIG. 7B. The stretch resistance member 270 further includes a connecting portion 274 that takes the form of a filament or the like. For example, the joint 274 can be formed from a polymer material such as a suture filament material. During the assembly of the closure coil 300, the extension resistance member 270 initially exists as a mere single joint 274 extending from the distal cap 271. The free end of this junction 274 is provided by an opening 250 located at the distal end 234 of the delivery wire adapter 230. The free end of the junction 274 is then pulled back towards the distal end 304 of the closing coil 300, where it is joined to the distal cap 272 to complete the structure as shown in FIGS. 6A, 6B and 7B. The body is formed. Thermal bonding can be used to bond or secure the free end of the joint 274 to the distal cap 272. Of course, other joining techniques can also be used depending on the nature of the material used for the stretch resistance member 270. They include, for example, welding, adhesive junctions and the like. However, the use of the stretch resistance member 270 is completely optional. In other embodiments, the closing coil 300, which does not include the extension resistance member 270, can be utilized.

FIG. 7A shows a cross-sectional view of the closing coil 300 along the line segment AA of FIG. 6A. The two joints 274 of the extension resistance member 270 are depicted in the lumen 306 of the closing coil 300. FIG. 7B is an enlarged detailed view of detail B of FIG. 6B. The distal cap 272 of the extension resistance member 270 is depicted on the distal end 304 of the closing coil 300. FIG. 7C is an enlarged detailed view of detail C of FIG. 6A. The delivery wire adapter 230 is shown as connecting the closing coil 300 and the delivery wire 210.

FIG. 8 shows an exemplary configuration of the closed coil 300 in its natural state. In the natural state, the closed coil 300 deforms from, for example, the linear configuration shown in FIGS. 6A and 6B to a second shape. The second shape can include various two-dimensional and three-dimensional shapes. FIG. 8 is merely an example of the second shape of the closed coil 300, and other shapes and configurations are expected to be included within the scope of the present invention. Also, the closed coil 300 can incorporate synthetic fibers on all or part of the closed coil 300, as is conventionally known. These fibers may be attached directly to the coil winding 308, or may be integrated within the closed coil 300 using a woven or braided construction.

The delivery wire adapter 230 offers a number of advantages over previous embolic coil feeding systems. First, the delivery wire adapter 230 is a relatively short but durable coupling between the delivery wire 210 and the closing coil 300. There are no longer any long, stiff parts of the feed assembly that are prone to kick-back. Therefore, the delivery wire adapter 230 reduces or eliminates repulsion or bounce of the delivery wire assembly 200. The delivery wire adapter 230 also reduces the risk of the closure coil 300 escaping into the parent vessel. In addition, the delivery wire adapter 230 can be used with closure coils 300 of various sizes. Relatively easy adjustment of the dimensions of the delivery wire adapter 230 can be made to provide closing coils 300 of various dimensions.

The small size delivery wire adapter 230 provides greater flexibility of the coil within the aneurysm, thus reducing the delivery force required for sufficient deployment of the closure coil 300. Finally, the delivery wire adapter 230 provides a strong bond between the delivery wire 210 and the closing coil 300. For example, a strong axial force (eg, a force that pulls the delivery wire assembly 200 and the closure coil 300 proximally when the closure coil 300 is fixed) is a junction between the delivery wire 210 and the closure coil 300. Will not cause any problems. Rather, the delivery wire adapter 230 is strong enough so that any failure mode occurs at the closing coil 300 for small coil wire diameters, or the delivery wire / adapter junction for large coil wire diameters.

Another advantage of the system 10 described herein is that it utilizes a bipolar arrangement of conductive paths 242,244 in the actual delivery wire assembly 200. There is no longer a need to use a separate needle electrode that is inserted into the patient's inguinal region. Instead, a return or ground electrode is integrated with the delivery wire assembly 200. This results in a more reproducible separation time, not only because of the need for needle electrodes, but also because there is no longer a large amount of tissue through which the current must pass.

The delivery wire adapter 230 can be manufactured using a sheet or substrate 280 on which a plurality of delivery wire adapters are formed. FIG. 9A shows that multiple delivery wire adapters 230 are formed on a single substrate 280. The sheet or substrate 280 can include stainless steel, such as a hardened stainless steel 304 alloy. Its thickness can vary depending on the desired thickness of the delivery wire adapter 230, but is generally less than 0.003 inches. The delivery wire adapter 230 can be formed on the substrate 280 by photochemical etching. Of course, various delivery wire adapters 230 can be formed on the substrate 280 through laser cutting, EDM processing, electroplating or other processes. As can be seen in FIGS. 9A and 9B, the delivery wire adapter 230 is initially provided with extra material 282 on one side of the delivery wire adapter 230. The excess material 282 is cut along the cut 284, whereby the final delivery wire adapter 230 is manufactured. A clipper or the like may be used to cut off excess material. The sharp edges formed on the delivery wire adapter 230 can be reduced by grit blasting, tumbling or electropolishing.

FIG. 10 shows the closure coil 300 away from the delivery wire 210 of the delivery wire assembly 200. Specifically, the delivery wire assembly 200 is located within a delivery catheter 100 located within the blood vessel 502. The delivery catheter 100 is typically advanced and placed in place under fluoroscopy by a physician. Once in place, the delivery wire assembly 200 can be advanced distally through the lumen 106 of the delivery catheter 100. Once the delivery wire assembly 200 is advanced and the closure coil 300 is placed within the aneurysm 500, the physician activates the power supply 400 by pressing trigger 408, causing a current flow along the delivery wire 210. be able to. After a few seconds, the electrolytic separation region 220 exposed to the conductive solution (physiological solution or saline wash) dissolves. The power supply device 400 detects the destruction of the electrolytic separation region 220 and stops the current supply. FIG. 10 shows the separation of the closing coil 300 from the delivery wire assembly 200.