Patent Publication Number: US-2021187264-A1

Title: Neurovascular insertion tool

Description:
CROSS REFERENCE 
     This application claims priority of U.S. Provisional Application No. 62/951,742 filed Dec. 20, 2019. The entire contents of which are hereby incorporated by reference. 
    
    
     FIELD OF INVENTION 
     The present invention generally relates to intravascular medical treatments, and more particularly, to an insertion apparatus for introducing a neurovascular device into a microcatheter via a hemostasis valve. 
     BACKGROUND 
     Typically, during a thrombectomy procedure, an insertion tool is used to introduce a neurovascular device into a microcatheter via a hemostasis valve, such as a rotating hemostasis valve (RHV). Examples of the neurovascular device include, but not limited to, a mechanical thrombectomy device, a neurovascular access device, a neurovascular balloon device, a neurovascular assist device, and a neurovascular clot removal/flow device. 
     The hemostasis valve is attached to a proximal end of the microcatheter. The proximal end of the microcatheter includes a microcatheter hub that allows for the attachment of the hemostasis valve. The geometry of these microcatheter hubs vary in design and dimensions across commercial microcatheter designs. The neurovascular device is loaded into the microcatheter via the hemostasis valve by using the insertion tool. The insertion tool is advanced through the hemostasis valve into the microcatheter hub until it cannot be advanced any further. The neurovascular device is then tracked to the treatment location through the microcatheter. When loading the neurovascular device, the neurovascular device should not expand. In other words, the neurovascular device should remain in a wrapped state as it transitions from the insertion tool to the microcatheter. 
     However, it has been observed that during introduction of the neurovascular device, if the insertion tool is not positioned correctly, the neurovascular device does not load correctly into the microcatheter. For example, the insertion tool is prone to moving when introducing the neurovascular device into the microcatheter, when the hemostasis valve is not tight enough. 
     Further, the different microcatheter hub geometries result in a large variation in the distance that the insertion tool can be advanced into the microcatheter hub. If the insertion tool is too distal in the microcatheter, it can result in failed delivery of the neurovascular device which can potentially damage the neurovascular device. The different proximal hub geometries and hemostasis valve seals can also result in the insertion tool being pushed distally back out of the microcatheter hub. This can result in premature deployment of the neurovascular devices in the hemostasis valve resulting in a failed introduction, potentially damaging the device. 
     Due to the inaccurate placement of the insertion tool, the neurovascular device becomes damaged when being deployed in a hub of the microcatheter, rather than transitioning directly into a shaft of the microcatheter. The neurovascular device is then either thrown in the trash or returned to the manufacturer as a complaint unit. 
     There is a need for an improved insertion tool design that possesses geometric features that will make the insertion tool more universal and compatible with a range of microcatheter hub geometries that are commercially available. There is a need for an improved insertion tool design that reduces a gap between a distal tip of the insertion tool and the microcatheter in order to prevent potential snagging of the neurovascular device in the microcatheter hub. There is a need for an improved insertion tool design that reduces the possibility of the insertion tool backing out of the hemostasis valve during the introduction of the neurovascular device into the microcatheter. For example, there is a need for an improved surface finish of the insertion apparatus to improve grip on the hemostasis valve. 
     SUMMARY 
     It is an object of the present invention to provide systems, devices, and methods to meet the above-stated needs. Generally, it is an object of the present invention to provide an improved insertion apparatus that simplifies loading of neurovascular device into microcatheter. In one example, the insertion apparatus can include a tapered distal tip, allowing the insertion apparatus to reach the microcatheter with no gap. In another example, the insertion apparatus can include an uneven outer surface along its longitudinal body through laser ablation of material to form protrusions, forming taper features, forming wave patterns or thread extrusions. 
     An example insertion apparatus can introduce a neurovascular device into a microcatheter via the RHV. The example insertion apparatus can include a longitudinal body. The longitudinal body can define a lumen therethrough that allows the neurovascular device to pass through. The longitudinal body can include a proximal portion. The proximal portion can include a first color. The longitudinal body can include a distal portion. The distal portion can include a second color different from the first color. The longitudinal body can include a boundary between the proximal portion and the distal portion. The microcatheter can be first coupled to the RHV before introducing the insertion apparatus into the microcatheter. When the insertion apparatus is correctly positioned relative to the microcatheter and the RHV, the boundary can be aligned with a proximal end of the RHV 
     Another example insertion apparatus for introducing a neurovascular device into a microcatheter via an RHV can include a longitudinal body. The longitudinal body can define a lumen therethrough that allows the neurovascular device to pass through. The insertion apparatus can include a ledge disposed on an outer surface of the longitudinal body that prevents a complete entry of the insertion apparatus into a proximal end of the RHV. The microcatheter can be first coupled to the RHV before introducing the insertion apparatus into the microcatheter. When the insertion apparatus is correctly positioned relative to the microcatheter and the RHV for introducing the neurovascular device into the microcatheter, the ledge can be aligned with the proximal end of the RHV. 
     The ledge can include a width greater than a diameter of an opening of the proximal end of the RHV. The diameter of the opening can allow a partial entry of the insertion apparatus into the proximal end of the RHV. 
     The ledge can be disposed towards a distal end of the longitudinal body. The insertion apparatus can include a second ledge disposed towards a proximal end of the longitudinal body. 
     Yet another example insertion apparatus for introducing a neurovascular device into a microcatheter via an RHV can include a longitudinal body. The longitudinal body can include a lumen therethrough that allows the neurovascular device to pass through. The longitudinal body can include a tapered distal portion sized to allow partial entry into a proximal end of a microcatheter shaft. The tapered distal portion can include an outer diameter sized to prevent complete deployment into the microcatheter. The outer diameter can be greater than 0.021 inches. The longitudinal body can include a tapered proximal portion. The tapered distal portion can include a length of approximately 10 mm. 
     A further example insertion apparatus for introducing a neurovascular device into a microcatheter via an RHV can include a longitudinal body. The longitudinal body can define a lumen therethrough that allows the neurovascular device to pass through. The insertion apparatus can include an uneven outer surface. The uneven outer surface can prevent a backward movement of the insertion apparatus from the microcatheter when introducing the neurovascular device into the microcatheter. A distal portion of the longitudinal body can include a distalmost taper to allow the distal portion to advance partially into the microcatheter. The uneven outer surface can include a sealing relationship with respect to a seal of the RHV. The uneven outer surface can define a plurality of tapers along a length of the longitudinal body to reduce movement of the insertion apparatus during introduction of the neurovascular device into the microcatheter. The plurality of tapers can include a first plurality of tapers inclined in a first direction at a first side of the insertion apparatus. The plurality of tapers can include a second plurality of tapers inclined in a second direction at a second side of the insertion apparatus. The second direction can be opposite from the first direction. The longitudinal body can define a length in a range from about 410 mm to about 600 mm. The RHV can further include a seal. The seal can include a recess formed in the seal. The uneven outer surface can include at least one threaded extrusion engaging with the recess formed in the seal of the RHV. The threaded extrusion can include a thickness less than a width of the recess formed in the seal of the RHV. The uneven outer surface can include a plurality of protrusions. At least one protrusion can include a length from about 2 mm to about 3 mm. The uneven outer surface can include a knurled surface. The uneven outer surface can include a wave pattern along a length of the longitudinal body. The RHV can further include a recess of a seal. The recess of the seal can include a complementary profile engaging with the uneven outer surface. 
     An example method for introducing a neurovascular device into a microcatheter via an RHV can include one or more of the following steps presented in no particular order. The method can include applying the RHV to the microcatheter. The method can include inserting an insertion apparatus into the microcatheter through the RHV. The method can include matching a boundary between a proximal portion and a distal portion of the insertion apparatus with a proximal end of the RHV. The proximal portion can include a first color. The distal portion can include a second color different from the first color. The method can include inserting the neurovascular device into the microcatheter through a lumen defined in the insertion apparatus. 
     Another example method for introducing a neurovascular device into a microcatheter via an RHV can include one or more of the following steps presented in no particular order. The method can include applying the RHV to the microcatheter. The method can include inserting an insertion apparatus into the microcatheter through the RHV. The method can include contacting a ledge disposed on an outer surface of a longitudinal body of the insertion apparatus to a proximal end of the RHV. The method can include inserting the neurovascular device into the microcatheter through a lumen defined in the insertion apparatus. The method can include defining a width of the ledge greater than a diameter of an opening of the proximal end of the RHV. The method can include allowing a partial entry of the insertion apparatus into the proximal end of the RHV based on the diameter of the opening. 
     Yet another example method for introducing a neurovascular device into a microcatheter via an RHV can include one or more of the following steps presented in no particular order. The method can include applying the RHV to the microcatheter. The method can include inserting a tapered distal portion of an insertion apparatus into a proximal end of a microcatheter shaft through the RHV. The method can include configuring the tapered distal portion to restrict full insertion of the tapered distal portion into the microcatheter. The method can include inserting the neurovascular device into the microcatheter through a lumen defined in the insertion apparatus. 
     A further example method for introducing a neurovascular device into a microcatheter via an RHV can include one or more of the following steps presented in no particular order. The method can include applying the RHV to the microcatheter. The method can include inserting a longitudinal body of an insertion apparatus into the microcatheter through the RHV. The method can include preventing a backward movement of the insertion apparatus from the microcatheter when introducing the neurovascular device into the microcatheter using an uneven outer surface of the longitudinal body. The method can include inserting the neurovascular device into the microcatheter through a lumen defined in the insertion apparatus. 
     All the example methods described above can include additional steps as would be appreciated and understood by a person of ordinary skill in the art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and further aspects of this invention are further discussed with reference to the 
       following description in conjunction with the accompanying drawings, in which like numerals indicate like structural elements and features in various figures. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating principles of the invention. The figures depict one or more implementations of the inventive devices, by way of example only, not by way of limitation. 
         FIG. 1  is an illustration of an example insertion apparatus for introducing the neurovascular device into the microcatheter via the RHV according to aspects of the present invention. 
         FIG. 2  is an illustration of another example insertion apparatus for introducing the neurovascular device into the microcatheter via the RHV according to aspects of the present invention. 
         FIG. 3  is another illustration of the example insertion apparatus of  FIG. 2  according to aspects of the present invention. 
         FIG. 4  is an illustration of yet another example insertion apparatus for introducing the neurovascular device into the microcatheter via the RHV according to aspects of the present invention. 
         FIG. 5  is another illustration of the example insertion apparatus of  FIG. 4  according to aspects of the present invention. 
         FIG. 6A  is an illustration of still another example insertion apparatus for introducing the neurovascular device into the microcatheter via the RHV according to aspects of the present invention. 
         FIG. 6B  is another illustration of the example insertion apparatus of  FIG. 6A  according to aspects of the present invention. 
         FIG. 6C  is still another illustration of the example insertion apparatus of  FIG. 6A  according to aspects of the present invention. 
         FIG. 6D  is yet another illustration of the example insertion apparatus of  FIG. 6A  according to aspects of the present invention. 
         FIG. 7  is an additional illustration of the example insertion apparatus of  FIG. 6A  according to aspects of the present invention. 
         FIG. 8  is an illustration of a further example insertion apparatus for introducing the neurovascular device into the microcatheter via the RHV according to aspects of the present invention. 
         FIG. 9  is an illustration of a certain example insertion apparatus for introducing the neurovascular device into the microcatheter via the RHV according to aspects of the present invention. 
         FIG. 10  is an illustration of an additional example insertion apparatus for introducing the neurovascular device into the microcatheter via the RHV according to aspects of the present invention. 
         FIG. 11  is an illustration of a still further example insertion apparatus for introducing the neurovascular device into the microcatheter via the RHV according to aspects of the present invention. 
         FIG. 12  is a flow chart illustrating steps for introducing the neurovascular device into the microcatheter via the insertion apparatus according to aspects of the present invention. 
         FIG. 13  is another flow chart illustrating steps for introducing the neurovascular device into the microcatheter via the RHV according to aspects of the present invention. 
         FIG. 14  is yet another flow chart illustrating steps for introducing the neurovascular device into the microcatheter via the RHV according to aspects of the present invention. 
         FIG. 15  is still another flow chart illustrating steps for introducing the neurovascular device into the microcatheter via the RHV according to aspects of the present invention. 
         FIG. 16  is an additional flow chart illustrating steps for introducing the neurovascular device into the microcatheter via the RHV according to aspects of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     As used herein, the terms “about” or “approximately” for any numerical values or ranges indicate a suitable dimensional tolerance that allows the part or collection of components to function for its intended purpose as described herein. More specifically, “about” or “approximately” can refer to the range of values ±20% of the recited value, e.g. “about 90%” can refer to the range of values from 71% to 99%. 
     An example of an insertion apparatus  110  is illustrated in  FIG. 1  for introducing a neurovascular device  170  into a microcatheter  130  via an RHV  140 . The microcatheter  130  can include a microcatheter shaft  131  and a microcatheter hub  132  that are all part of the same microcatheter assembly. Examples of the neurovascular device  170  can include, but not limited to, a mechanical thrombectomy device, a neurovascular access device, a neurovascular balloon device, a neurovascular assist device, and a neurovascular clot removal/flow device. 
     The insertion apparatus  110  can have a longitudinal body  150 . The longitudinal body  150  can define a lumen  152  therethrough that allows the neurovascular device  170  to pass through. The longitudinal body  150  can include a proximal portion  154  having a first color and a distal portion  156  having a second color different from the first color. The longitudinal body  150  can include a boundary  158  between the proximal portion  154  and the distal portion  156 . The boundary  158  can be aligned with a proximal end  160  of an RHV  140  when the insertion apparatus  110  is correctly positioned relative to the microcatheter  130  and the RHV  140 , when the microcatheter  130  is coupled to the RHV  140 . 
     Each end of the insertion apparatus  110  can be dyed a different color. This color change can allow the physician to know when the insertion apparatus  110  has been correctly positioned into the microcatheter hub  132 . During loading, the physician can see if the insertion apparatus  110  begins to slip out of location based on color change. The color change can signify correct seating. 
     Another example of an insertion apparatus  210  is illustrated in  FIG. 2  for introducing a neurovascular device  270  into a microcatheter  230  via an RHV  240 . The insertion apparatus  210  can include a longitudinal body  250  defining a lumen  252  therethrough that allows the neurovascular device  270  to pass through. The insertion apparatus  210  can include a ledge  254  disposed on an outer surface  256  of the longitudinal body  250 . Before introducing the neurovascular device  250  into the microcatheter  230 , the microcatheter  230  can be first coupled to the RHV  240 . When the insertion apparatus  210  is correctly positioned relative to the microcatheter  230  and the RHV  240  for introducing the neurovascular device  270  into the microcatheter  230 , the ledge  254  can prevent a complete entry of the insertion apparatus  210  into a proximal end  260  of the RHV  240 , when the ledge  254  is aligned with the proximal end  260  of the RHV  240 . 
     As illustrated in  FIG. 2 , the ledge  254  can include a width “W” greater than a diameter “d” of an opening  262  of the proximal end  260  of the RHV  240 . The diameter “d” of the opening  262  can allow a partial entry of the insertion apparatus  210  into the proximal end  260  of the RHV  240 . 
     In one example as illustrated in  FIG. 3 , the ledge  254  can be disposed towards a distal end  272  of the longitudinal body  250 . A second ledge  258  can be disposed towards a proximal end  274  of the longitudinal body  250 . As such, the ledge can be positioned at each end of the insertion apparatus  210  to allow the physician to know when the insertion apparatus  210  has been correctly seated in the microcatheter hub  232 . During loading, the physician can see if the insertion apparatus  210  begins to slip out of location when the ledge  254  or  258  does not sit directly at the correct location. In one example, at least one of the ledges  254 ,  258  can sit on the RHV  240 . 
     Yet another example of an insertion apparatus  410  is illustrated in  FIG. 4  for introducing a neurovascular device  470  into a microcatheter  430  via an RHV  440 . The insertion apparatus  410  can include a longitudinal body  450 . The longitudinal body  450  can include a lumen  452  therethrough that allows the neurovascular device  470  to pass through. The longitudinal body  450  can include a tapered distal portion  456  sized to allow partial entry into a proximal end  432  of a microcatheter shaft  431 . 
     In one example as illustrated in  FIG. 5 , the tapered distal portion  456  can include an outer diameter “d 1 ” sized to prevent complete deployment into the microcatheter  430 . 
     In one example, the outer diameter “d 1 ” can be greater than 0.021 inches, while an inner diameter of the microcatheter  430  can be approximately 0.021 inches or greater, so that the insertion apparatus  410  can be inserted into the microcatheter  430 . The outer diameter “d 1 ” can be greater than the inner diameter of the microcatheter  430  to prevent the insertion apparatus  410  sliding into the microcatheter  430 . Preferably, an inner diameter of the insertion apparatus  410  can be greater than 0.021 inches to minimize loading forces. In one embodiment, the inner diameter of the microcatheter  430  can be in a range from 0.016 inches to 0.027 inches. 
     In one example, the tapered distal portion  456  can have a length “TL” of approximately 10 mm. 
     In one example as seen in  FIG. 5 , the longitudinal body  450  can include a tapered proximal portion  458 . 
     The insertion apparatus  450  can be tapered on each end so that that each end can have an outer diameter “d 1 ”. The outer diameter “d 1 ” can be greater than 0.021 inches to allow it to sit inside a lumen of the microcatheter  430 . This can prevent the insertion apparatus  410  being inadvertently deployed in the microcatheter hub. 
     Referring to  FIG. 5 , the insertion apparatus  410  can have a length “L” in a range between approximately 410 mm and approximately 600 mm. The longitudinal body  650 ,  1150  can define the same length “L” in a range from about 410 mm to about 600 mm. In one example, the length “L” can be approximately 600 mm. Physicians can prefer to wrap the insertion apparatus around their hand while gripping the RHV. The length “L”, such as 600 mm, can allow for a more secure grip while introducing the neurovascular device into the microcatheter. 
     A still another example of an insertion apparatus  610 ,  810 ,  910 ,  1010 ,  1110  is illustrated in  FIGS. 6A-11  for introducing a neurovascular device  670  into a microcatheter  630  via an RHV  640 . The insertion apparatus  610  can include a longitudinal body  650 ,  1150 . The longitudinal body  650 ,  1150  can define a lumen  652 ,  852 ,  1152  therethrough that allows the neurovascular device  670  to pass through. The longitudinal body can include an uneven outer surface  654 ,  854 ,  954 ,  1154  preventing a backward movement of the insertion apparatus  610  from the microcatheter  630  when introducing the neurovascular device  670  into the microcatheter  630 . 
       FIG. 6B  can represent a longitudinal cross section of a full assembly of the insertion apparatus  610 , the microcatheter  630  and the neurovascular device  670 . As illustrated in  FIG. 6B , the neurovascular device  670  can move forward into a microcatheter shaft  631  in a direction as represented by an arrow “F”. In  FIG. 6B , a shaded or hatched region enclosing the microcatheter shaft  631  and the microcatheter hub  632  can represent a microcatheter hub wall  633 . As seen in  FIG. 6B , the microcatheter shaft  631  can define a microcatheter shaft lumen  634  for receiving the neurovascular device  670 . 
     In one example as illustrated in  FIG. 6D , the insertion apparatus  610  can define a lumen  652  therein for accommodating the neurovascular device  670 . 
     Preferably, the lumen  652  can have an inner diameter greater than 0.021 inches to minimize loading forces. In one embodiment, the lumen  652  can have an inner diameter of about 0.024 inches. 
     The insertion apparatus  610 ,  810 ,  910 ,  1010 ,  1110  can have one or more geometric features along its outer surface  654 ,  854 ,  954 ,  1154  to improve the contact between an RHV seal  642 ,  842 ,  1142  and the insertion apparatus. These geometric features can be a roughened outer surface on the insertion apparatus. The roughened outer surface can prevent the insertion apparatus  610 ,  810 ,  910 ,  1010 ,  1110  from moving distally back out of the microcatheter hub  632 , therefore significantly reducing the possibility of a failed introduction or premature deployment of the neurovascular device  670 . 
     In one example, a distal portion  656  of the longitudinal body  650  can include a distalmost taper  671  to allow the distal portion  656  to advance partially into the microcatheter  630 . As shown in  FIG. 6D , the distalmost taper  671  can form an angle θ in a range of approximately 10°-20° with respect to a longitudinal axis “A” of the insertion apparatus  610 . The distalmost taper  671  can enable a distal tip of the insertion apparatus  610  to further advance into the microcatheter hub  632 . The distalmost taper  671  can allow the insertion apparatus  610  to advance to a most distal end of the microcatheter hub  632 , therefore significantly reducing the possibility of a failed delivery of the neurovascular device  670  into the microcatheter  630 , which can otherwise occur due to a geometry of the microcatheter hub  632  or a partial deployment of the neurovascular device  670  in the microcatheter hub  632 . 
     In one example, with reference to  FIG. 7 , the longitudinal body  650  can have a proximal most taper  673 . The distalmost taper  671  and the proximal most taper  673  each can have a length “TL” greater than 8.5 mm. In one example, the length “TL” can be approximately 10 mm. Each of the distalmost taper  671  and the proximal most taper  673  can taper from a maximum outer diameter of approximately 0.045 inches to a minimum outer diameter of approximately 0.035 inches as illustrated in  FIGS. 6D, 8 and 11 . 
     In one example, the uneven outer surface  654 ,  854  can form a sealing relationship with respect to a seal  642 ,  842 ,  1142  of the RHV  640 . 
     In one example, the uneven outer surface  654  can include a plurality of tapers  672 ,  674  along the length of the insertion apparatus outer surface  654  to reduce movement of the insertion apparatus  610  during introduction of the neurovascular device  670  into the microcatheter  630 . The plurality of tapers  672 ,  674  can be applied to both sides of the insertion apparatus to allow the insertion apparatus to be used from both sides. In one example, the plurality of tapers can include a first plurality of tapers  672  inclined in a first direction at a first side of the insertion apparatus  610 , and a second plurality of tapers  674  inclined in a second direction at a second side of the insertion apparatus. The second direction can be opposite from the first direction. The tapers  672 ,  674  can server to reduce movement of the insertion apparatus when introducing the neurovascular device into the microcatheter. 
     In one example, the tapers  672  can be positioned at a distal end of the insertion apparatus  610 , while tapers  674  can be positioned at a proximal end of the insertion apparatus  610 . As illustrated in  FIG. 7 , the taper directions of tapers  672 ,  674  can be mirrored at a midpoint of the insertion apparatus, so that the insertion apparatus  610  can be used either way. 
     Each of the tapers  672 ,  674  along the length of the insertion apparatus can have a length shorter than the length “TL” of the distalmost taper  671  or the proximal most taper  673  in order to improve the grip the closed RHV seal  642  has on the insertion apparatus  610 . 
     In one example as illustrated in  FIG. 6C , when the RHV seal  642  closes on the insertion apparatus  610 , tapers  672  or tapers  674  can be locked or gripped by the RHV seal  642  or embedded into the RHV seal  642  to provide additional grip, preventing the insertion apparatus  610  from backing out of RHV  640  during device delivery. The RHV seal  642  can close tight to the insertion apparatus outer diameter. The RHV seal  642  can deform to form a tight grip on the outer surface of the insertion apparatus  610 . The RHV seal  642  can deflect to conform with the outer surface of the insertion apparatus  610 . At this point, the RHV seal  642  can be tightened down onto the insertion apparatus  610  to aid holding it in place in the microcatheter hub. As a result, the insertion apparatus  610  can be prevented from backing out of the RHV  640  when introducing the neurovascular device  670  into the microcatheter  630 . 
     With reference to  FIG. 6C , tapers  672  or  674  can prevent the insertion apparatus  610  moving backwards in a direction as represented by an arrow “B” when introducing the neurovascular device  670  into the microcatheter shaft  631 . 
     With reference to  FIGS. 6D, 8 and 11 , when the RHV seal  642  closes on the insertion apparatus  610 , the RHV seal  642  can deform around the insertion apparatus  610  to form a firm grip on the insertion apparatus  610 . As a result, the RHV seal  642  can prevent the insertion apparatus  610  from backing out of the RHV  640  when introducing the neurovascular device  670  into the microcatheter shaft  631 . 
     In one example as illustrated in  FIG. 8 , the RHV  640  can include a seal  842 . The seal  842  can include a recess  844  formed in the seal  842 . The uneven outer surface  854  can include at least one threaded extrusion  856  engaging with the recess  844  formed in the seal  842  of the RHV  640 . 
     In one example, the threaded extrusion  856  can include a thickness “T 1 ” less than a width “W 1 ” of the recess  844  formed in the seal  842  of the RHV  640 . 
     In one example as illustrated in  FIG. 9 , laser engraved pattern on an outer surface of the insertion apparatus  910  can improve RHV grip, preventing movement. The uneven outer surface  954  can include a plurality of protrusions  980 . At least one protrusion  980  can include a length “PL” from about 2 mm to about 3 mm. The length “PL” can be slightly small than an approximate size of the RHV seal. 
     Referring to  FIG. 8 , the threaded extrusion  856  can be formed along the outer surface of the insertion apparatus to improve tightness between the RHV seal and the insertion apparatus when the RHV seal grips the insertion apparatus. 
     In one example as illustrated in  FIG. 10 , the uneven outer surface  1054  can include a knurled surface to improve RHV grip. 
     In one example as illustrated in  FIG. 11 , the uneven outer surface  1154  can include a wave pattern  1160  along a length of the longitudinal body  1150  to improve grip of RHV on the insertion apparatus. The RHV seal  1142  can include a recess  1144 . The recess  114  can include a complementary profile  1170  engaging with the uneven outer surface  1154 . The RHV seal  1142  can be closed tight to the insertion apparatus  1110 . The RHV seal  1142  is deformable to conform with the wave pattern  1160 . 
       FIG. 12  is a flow diagram illustrating an example method  1200  for inserting the neurovascular device  670  into the microcatheter  630 . The method  1200  can include one or more of the following steps presented in no particular order. 
     At step  1202 , the neurovascular device  670  can be loaded into the insertion apparatus  610 . 
     At step  1204 , the RHV  640  can be attached to the microcatheter hub  632 . A physician can apply the RHV  640  to the microcatheter hub  632  before inserting the insertion apparatus  610  into the microcatheter  630 . In one example, in order to ensure that the below designs work correctly the RHV  640  of a specific length must be provided. 
     At step  1206 , the insertion apparatus  610 , with the neurovascular device  670  preloaded therein, can be introduced into the RHV  640 . 
     At step  1208 , the insertion apparatus  610  can be positioned tight against a proximal end  635  of a microcatheter shaft  631  as illustrated in  FIG. 6B . 
     At step  1210 , the RHV seal  642  can be closed down on the insertion apparatus  610  to hold the insertion apparatus  610  in place. 
     At step  1212 , the neurovascular device  670  can be moved forward from the insertion apparatus  610  into the microcatheter  630  until the neurovascular device  670  is fully introduced into the microcatheter  630 . 
     At step  1214 , once the neurovascular device  670  is fully introduced into the microcatheter  630 , the RHV seal  642  can be loosened in order to remove the insertion apparatus  670 . 
     At step  1216 , the insertion apparatus  670  can be pulled proximally off a shaft  675  of the neurovascular device  670 . 
       FIG. 13  is another flow diagram illustrating an example method  1300  for inserting the neurovascular device  170  into the microcatheter  130  via the RHV  140 . The method  1300  can include one or more of the following steps presented in no particular order. 
     At step  1302 , the RHV  140  can be applied to the microcatheter  130 . 
     At step  1304 , the insertion apparatus  110  can be inserted into the microcatheter  130  through the RHV  140 . 
     At step  1306 , the boundary  158  between the proximal portion  154  and the distal portion  156  of the insertion apparatus  110  can be matched with the proximal end  160  of the RHV  140 . The proximal portion  154  can include a first color. The distal portion  156  can include a second color different from the first color. 
     At step  1308 , the neurovascular device  170  can be inserted into the microcatheter  130  through the lumen  152  defined in the insertion apparatus  110 . 
       FIG. 14  is yet another flow diagram illustrating an example method  1400  for inserting the neurovascular device  270  into the microcatheter  230  via the RHV  240 . The method  1400  can include one or more of the following steps presented in no particular order. 
     At step  1402 , the RHV  240  can be applied to the microcatheter  230 . 
     At step  1404 , the insertion apparatus  210  can be inserted into the microcatheter  230  through the RHV  240 . 
     At step  1406 , the ledge  254  disposed on the outer surface  256  of the longitudinal body  250  of the insertion apparatus  210  can be contacted to the proximal end  260  of the RHV  240 . 
     At step  1408 , the neurovascular device  270  can be inserted into the microcatheter  230  through the lumen  252  defined in the insertion apparatus  210 . 
     In one example, the ledge  254  can have a width “W” greater than a diameter “d” of the opening  262  of the proximal end  260  of the RHV  240 , allowing a partial entry of the insertion apparatus  210  into the proximal end  260  of the RHV  240  based on the diameter “d” of the opening  262 . 
       FIG. 15  is a flow diagram illustrating an example method  1500  for introducing the neurovascular device  470  into the microcatheter  430  via the RHV  440 . The method  1500  can include one or more of the following steps presented in no particular order. 
     At step  1502 , the RHV  440  can be applied to the microcatheter  430 . 
     At step  1504 , the tapered distal portion  456  of the insertion apparatus  410  can be inserted into the proximal end  432  of the microcatheter shaft  431  through the RHV  440 . 
     At step  1506 , the tapered distal portion  456  can be configured to restrict full insertion of the tapered distal portion  456  into the microcatheter  430 . 
     At step  1508 , the neurovascular device  470  can be inserted into the microcatheter  430  through the lumen  452  defined in the insertion apparatus  410 . 
       FIG. 16  is a flow diagram illustrating an example method  1600  for introducing the neurovascular device  670  into the microcatheter  630  via the RHV  640 . The method  1600  can include one or more of the following steps presented in no particular order. 
     At step  1602 , the RHV  640  can be applied to the microcatheter  630 . 
     At step  1604 , the longitudinal body  650 ,  1150  of the insertion apparatus  610 ,  810 ,  910 ,  1010 ,  1110  can be inserted into the microcatheter  630  through the RHV  640 . 
     At step  1606 , a backward movement of the insertion apparatus  610 ,  810 ,  910 ,  1010 ,  1110  can be prevented from the microcatheter  630  when introducing the neurovascular device  670  into the microcatheter  630  using the uneven outer surface  654 ,  854 ,  954 ,  1154  of the longitudinal body  650 ,  1150 . 
     At step  1608 , the neurovascular device  670  can be inserted into the microcatheter  630  through the lumen  652 ,  852 ,  1152  defined in the insertion apparatus  610 ,  810 ,  910 ,  1010 ,  1110 . 
     Any of the example methods  1200 ,  1300 ,  1400 ,  1500  and  1600  can include additional steps as would be appreciated and understood by a person of ordinary skill in the art. The example method can be performed by an example system or a physician as disclosed herein, a variation thereof, or an alternative thereto as would be appreciated and understood by a person of ordinary skill in the art. 
     In one embodiment, the insertion apparatus may have a protrusion disposed on an outer surface of the insertion apparatus. The protrusion can form a spiral profile on the outer surface of the insertion apparatus. Both ends of the insertion apparatus may have a tapered profile to enhance ease of use and microcatheter capability. 
     The descriptions contained herein are examples of embodiments of the invention and are not intended in any way to limit the scope of the invention. As described herein, the invention contemplates many variations and modifications of the insertion apparatus. These modifications would be apparent to those having ordinary skill in the art to which this invention relates and are intended to be within the scope of the claims which follow.