Questions And Answers - Stryker Neuroform Instrucciones De Uso

6. Holding the Neuroform™ Microdelivery Stent System in one hand, and the guidewire in the other, advance
the Neuroform Microdelivery Stent System like a typical microcatheter by manipulating the Neuroform
Microdelivery Stent System and the guidewire. Advance the Neuroform Microdelivery Stent System so that the
undeployed Stent crosses the aneurysm neck.
Aneurysm Neck
³ 4 mm
Stent in 3F Microdelivery Catheter
Note: Advancing the 2F Stabilizer Catheter independently from advancing the 3F Microdelivery Catheter may cause
premature deployment of the Stent. Do not use the 2F Stabilizer Catheter to push the Stent out of the delivery system.
Note: Initially during advancement of the Neuroform Microdelivery Stent System, it is helpful to have an assistant
hold the end of the wire while the Neuroform Microdelivery Stent System is advanced into the body. However, as
the stent system approaches the intracranial circulation, a single operator should advance both the stent system
and the guidewire.
7. Gently pull back on the guidewire and Neuroform Microdelivery Stent System until the excess guidewire slack
is removed from the stent system and the tip of the 3F Microdelivery Catheter begins to move. Advance the
2F Stabilizer Catheter (slightly loosening the rotating hemostasis valve may be necessary) so that its tip contacts
the Stent and moves the Stent slightly within the 3F Microdelivery Catheter.
8. While holding the 3F Microdelivery Catheter in one hand and the 2F Stabilizer Catheter in the other hand, carefully
pull both Catheters together as a unit until the Stent is in the desired position. Position the markerband on the
3F Microdelivery Catheter so that it is a minimum of 4 mm distal to the aneurysm neck.
Note: The best fluoroscopic view for positioning the Stent for deployment is the view that shows the vessel distal to
the aneurysm. This view may not be the same view as that used as the working position for aneurysm embolization.
9. When the distal end of the Stent is in the desired location, deploy the Stent by holding the 2F Stabilizer Catheter
steady with one hand while continuing to carefully withdraw the 3F Microdelivery Catheter with other hand.
This will deploy the Stent.
10. As the tip of the 3F Microdelivery Catheter passes the Stent, you will see the markerbands on the distal end of
the Stent spread out from one another. This is the Stent opening. Continue deploying the Stent in one continuous
smooth motion. Do not attempt to move the Stent after it has begun to deploy. Be careful not to advance the
3F Microdelivery Catheter as the Stent is deploying.
11. After the Stent is completely deployed, remove the delivery system.
Aneurysm Embolization
1. The aneurysm embolization can begin immediately. Standard microcatheters accepting 0.25 mm (0.010 in),
0.36 mm (0.014 in), or 0.46 mm (0.018 in) guidewires with distal tip ≤ 2.0F may be carefully placed through the
interstices of the Stent to place embolic coils in the aneurysm.
Note: Carefully watch the Stent markerbands when passing through the deployed Stent with embolic coiling
microcatheters to avoid dislodging the Stent.
2. Perform a standard embolic coiling procedure using accepted embolic coiling practices.
Table 1. Neuroform Microdelivery Stent System Recommended Sizing Guidelines
Self
Labeled Labeled Recommended
Expanded
Stent Stent Vessel
Stent
Diameter Length Diameter Interconnects
1 2
Diameter
(mm) (mm) (mm)
(mm)
2.5 10 3.0 >2.0 and ≤2.5
2.5 15 3.0 >2.0 and ≤2.5
2.5 20 3.0 >2.0 and ≤2.5
3.0 10 3.5 >2.5 and ≤3.0
3.0 15 3.5 >2.5 and ≤3.0
3.0 20 3.5 >2.5 and ≤3.0
3.0 30 3.5 >2.5 and ≤3.0
3.5 10 4.0 >3.0 and ≤3.5
3.5 15 4.0 >3.0 and ≤3.5
3.5 20 4.0 >3.0 and ≤3.5
3.5 30 4.0 >3.0 and ≤3.5
4.0 10 4.5 >3.5 and ≤4.0
4.0 15 4.5 >3.5 and ≤4.0
4.0 20 4.5 >3.5 and ≤4.0
4.0 30 4.5 >3.5 and ≤4.0
4.5 10 5.0 >4.0 and ≤4.5
4.5 15 5.0 >4.0 and ≤4.5
4.5 20 5.0 >4.0 and ≤4.5
4.5 30 5.0 >4.0 and ≤4.5
Select a Stent length that is at least 8 mm longer than the aneurysm neck to maintain a minimum of 4 mm on each side of the aneurysm
1
neck along the parent vessel.
Select a Stent diameter based on the sizing recommendations in Table 1 and based on the larger vessel diameter (proximal or distal
2
reference vessel diameter).
2F Stabilizer Catheter
³ 4 mm
3F Micro- 2F Minimum
delivery Stabilizer Maximum
Number of
Catheter Catheter Guidewire Catheter
Useable Useable Diameter
Length Length Diameter
0.36 mm
3 131 cm 150 cm
(0.014 in) (0.050 in)

QUESTIONS AND ANSWERS

Q: There seems to be binding of the Delivery System with the guidewire, making it difficult to advance the system.
What should I do?
A: Use of soft guidewires rather than support guidewires is recommended because soft guidewires facilitate
placement and deployment of the Stent. Excess tension can build up in the wire resulting in increased friction with
the delivery system.
This can be alleviated by retracting the guidewire and 3F Microdelivery Catheter to remove any accumulated tension.
If excessive friction continues, confirm that the 3F Microdelivery Catheter saline flush is functioning. With use,
guidewires can become kinked and lose their lubricious coatings. If excessive friction persists, consider removing
and discarding the guidewire and Delivery System and replacing it with a new one.
Generally, once the System is tracking forward over the guidewire, the operator should take advantage of the
momentum and continue tracking to a target site that is distal to the aneurysm neck because it is easier to move
the Delivery System from a distal to proximal location across the aneurysm neck instead of trying to reposition by
advancing the Delivery System.
Q: What is the optimal position of the Stent with respect to the aneurysm?
A: Generally, you should try to position the Stent so that each end of the Stent is secured in relatively normal areas of the
parent vessel. The Stent will be more stable if each end of the Stent can be anchored in at least 4-6 mm of normal vessel.
For example, for aneurysms located in the supraclinoid carotid, it may be better to secure the Stent by deploying the
distal end in the M1 than trying to deploy it in the few millimeters between the aneurysm and the ICA bifurcation.
When deploying the Stent, care should be taken to use a view that best shows the parent vessel distal to the
aneurysm, so that the distal end of the Stent can accurately be deployed with respect to the aneurysm. This view
may be different from the view used to advance the Delivery System, or the view used as a working position for
aneurysm embolization.
If you have accurately deployed the distal end of the Stent with respect to the aneurysm neck and you are confident
of the measurement of the neck, then you need not worry about the location of the proximal end of the stent. Just
continue to deploy the Stent, and the proximal end of the Stent will deploy correctly, even if it is difficult to see it
because of curves in the vessel.
Q: Which Stent size should I choose if I intend to place the Stent in a vessel that has a different diameter between the
proximal and distal ends of the Stent? Example: Vessel increases from 2 mm PCA to a 3.4 mm basilar.
A: Choose the Stent sized for the larger vessel. In this example, choose the 3.5 mm Stent. This Stent can be deployed
safely in the smaller PCA and will be well anchored in the basilar artery.
Q: Is there any problem with deploying the Stent across a branch vessel? Can the Stent be safely deployed across the
anterior choroidal artery? What about lenticulostriate arteries or perforators arising from the basilar?
A: No adverse events resulting from branch vessel occlusion or emboli to "jailed" vessels have been observed to
date in the limited clinical trials conducted on this Device (29 patients followed through hospital discharge with
follow-up continued for 6 months on 26 patients). Stents have been placed extending from the M1 to the ICA without
problems.
Q: A coil can be placed only partially into the aneurysm and cannot be retracted back into the embolization
microcatheter. Part of the coil is outside the aneurysm. What should I do?
A: Do not attempt to remove the partially deployed coil in this situation. The best approach is to place a second Stent
by inserting a 3F Microdelivery Catheter in the parent vessel parallel to the embolization microcatheter, gently pull
back the microcatheter containing the coil to unroll, but not stretch, the coil. Then deploy the second Stent to hold the
unrolled coil against the vessel wall, and finally detach the coil. This option is preferable to forcibly removing the coil
and risk dislodging the coil mass and Stent into the parent vessel. Strict attention to heparinization and antiplatelet
medication is important.
Q: A loop, or several loops, of a coil (especially a small diameter coil such as 2 mm) herniated through the interstices
of the Stent, and I am unable to reposition it. What should I do?
A: If the risk of leaving part of the coil in the parent vessel is unacceptable, a second Stent can be placed inside the
first Stent to pin the herniated coil portion against the wall of the vessel. Three-dimensional angiography can be very
useful when assessing whether or not a coil loop is inside the lumen of the Stent and in the parent vessel, or between
the wall of the vessel and the Stent. Strict attention to heparinization and antiplatelet medication is important.
Q: I have accidentally started to deploy the Stent, but it is not in the location that I wanted. What should I do?
A: The recommended course of action is not to try repositioning the Stent, but to continue to deploy the Stent where
it is, and then deploy a second Stent in the desired location. Animal studies have demonstrated that the Stent
endothelializes in less than 30 days.
Q: I misjudged the positioning of the Stent and have deployed it with one end adjacent to the aneurysm rather than in
the normal part of the parent vessel. What should I do?
Guide
A: Leave the wire in place, remove the 3F Microdelivery Catheter and 2F Stabilizer Catheter, and insert and deploy a
Inner
second Stent starting from inside from the first Stent to the normal portion of the parent vessel (telescoping Stents).
The second Stent should be of the same diameter or larger than the first.
WARRANTY
Stryker Neurovascular warrants that reasonable care has been used in the design and manufacture of this instrument.
This warranty is in lieu of and excludes all other warranties not expressly set forth herein, whether express or
implied by operation of law or otherwise, including, but not limited to, any implied warranties of merchantability or
fitness for a particular purpose. Handling, storage, cleaning and sterilization of this instrument as well as other factors
relating to the patient, diagnosis, treatment, surgical procedures and other matters beyond Stryker Neurovascular's
control directly affect the instrument and the results obtained from its use. Stryker Neurovascular's obligation under
this warranty is limited to the repair or replacement of this instrument and Stryker Neurovascular shall not be liable for
any incidental or consequential loss, damage or expense directly or indirectly arising from the use of this instrument.
Stryker Neurovascular neither assumes, nor authorizes any other person to assume for it, any other or additional
1.27 mm
liability or responsibility in connection with this instrument. Stryker Neurovascular assumes no liability with respect
to instruments reused, reprocessed or resterilized and makes no warranties, express or implied, including but not
limited to merchantability or fitness for a particular purpose, with respect to such instruments.
3
Black (K) ∆E ≤5.0