Cordis PRECISE Gebrauchsanleitung Seite 7

3. Select Stent Size
Measure the length of the target stricture to determine the
length of stent required. Allow for the area proximal and
distal to the tumor to be covered with the stent to protect
against impingement from further tumor growth.
Measure the diameter of the reference bile duct (proximal
and distal to the stricture). It is necessary to select a stent
which has an unconstrained diameter at least 1 mm larger
than the largest reference duct diameter to achieve secure
placement according to the following Stent Size Selection
Table.
Stent Size Selection Table
Lumen Unconstrained
Diameter Stent Diameter
5.5F Delivery System
3.0-4.0 mm
4.0-5.0 mm
5.0-6.0 mm
Refer to product labeling for stent length.
Note: The percent foreshortening of stent length is based
upon a mathematical calculation.
4. Preparation of Stent Delivery System
CAUTION: The 5.5F stent delivery system is shipped with
the Tuohy Borst valve OPEN. Be careful not to prematurely
deploy the stent during preparation. Prep the device in the
tray per instructions below. Close the Tuohy Borst valve
prior to removing the device from the tray.
a. Open the outer box to reveal the pouch containing the
stent and delivery system.
b. Check the temperature exposure indicator on the
pouch to confirm that the black dotted pattern with a grey
background is clearly visible. See Warnings section.
c. After careful inspection of the pouch looking for
damage to the sterile barrier, carefully peel open the
pouch and remove the tray. If it is suspected that
the sterility or performance of the device has been
compromised, the device should not be used.
d. While in the tray, attach a stopcock to the Y connection
on the Tuohy Borst valve.
e. Attach a 3-cc syringe filled with heparinized saline to the
open stopcock and apply positive pressure until
heparinized saline weeps from the proximal end of the
Tuohy Borst valve. Lock the Tuohy Borst valve and
continue to flush until heparinized saline weeps from the
distal catheter end.
f. Close the stopcock attached to the Tuohy Borst Y
connection.
g. Extract the stent delivery system from the tray. Examine
the device for any damage. Evaluate the distal end of the
catheter to ensure that the stent is contained within the
outer sheath. Do not use if the stent is partially deployed.
If a gap between the catheter tip and outer sheath tip
exists, open the Tuohy Borst valve and gently pull the
inner shaft in a proximal direction until the gap is closed.
Lock the Tuohy Borst valve after the adjustment by
rotating the proximal valve end in a clockwise direction.
Stent Deployment Procedure
1. Insertion of Introducer Sheath and Guidewire
a. Gain access at the appropriate site utilizing a 6F
(2.0 mm) or larger introducer sheath with a hemostatic
valve.
b. Insert a .018" (0.46 mm) guidewire of appropriate
length across the stricture to be stented via the
introducer sheath.
% Length
Foreshortening
5.0 mm 1.2%
6.0 mm 2.4%
7.0 mm 4.1%
2. Dilation of Stricture
Generally, no predilation is done with malignant strictures.
However, if the physician determines that predilation is
necessary, standard PTA techniques may be used. Remove
the PTA balloon catheter from the patient maintaining
stricture access with the .018" (0.46 mm) guidewire.
CAUTION: During dilation, never expand the balloon such
that bleeding or dissection complications could occur.
3. Introduction of Stent Delivery System
a. Flush the guidewire lumen of the stent delivery system
with heparinized saline utilizing a 10-cc syringe to expel
the air.
b. Ensure that the Tuohy Borst valve connecting the inner
shaft and outer sheath is locked by rotating the proximal
valve end in a clockwise direction to prevent premature
stent deployment.
c. Advance the device over the guidewire through the
hemostatic valve and sheath introducer.
NOTE: If resistance is met during delivery system
introduction, the system should be withdrawn and
another system should be used.
CAUTION: Always use an introducer sheath for the
implant procedure, to protect both the liver tract and
puncture site. An introducer sheath of a 6F (2.0 mm) or
larger size is recommended.
4. Slack Removal
a. Advance the stent delivery system past the lesion site.
b. Pull back the stent delivery system until the radiopaque
inner shaft markers (leading and trailing ends) move in
position so that they are proximal and distal to the target
lesion.
c. Ensure the device outside the patient remains flat and
straight.
CAUTION: Slack in the catheter shaft either outside or
inside the patient may result in deploying the stent
beyond the lesion site.
5. Stent Deployment
a. Verify that the delivery system's radiopaque inner
shaft markers (leading and trailing ends) are proximal
and distal to the target stricture.
b. Unlock the Tuohy Borst valve connecting the inner shaft
and outer sheath of the delivery system.
c. Ensure that the access sheath or guiding catheter does
not move during deployment.
d. Initiate stent deployment by retracting the outer sheath
while holding the inner shaft in a fixed position.
Deployment is complete when the outer sheath marker
passes the proximal inner shaft stent marker.
NOTE: The mechanism for stent deployment is outer
sheath retraction. Deployment is completed by
maintaining inner shaft position while retracting the
outer sheath and allowing the stent to expand.
NOTE: When more than one stent is required to open
the stricture, the more distal stent should be placed first.
Overlap of sequential stents is necessary but the amount
of overlap should be kept to a minimum.
6. Post-deployment Stent Dilatation
a. While using fluoroscopy, withdraw the entire delivery
system as one unit, over the guidewire, into the catheter
introducer sheath and out of the body. Remove the
delivery device from the guidewire.
NOTE: If any resistance is met during delivery system
withdrawal, advance the outer sheath until the outer
sheath marker contacts the catheter tip and withdraw the
system as one unit. (Do not remove guidewire.)
b. Using fluoroscopy, visualize the stent to verify full
deployment.
c. If incomplete expansion exists within the stent at any
point along the stricture, post deployment balloon
dilatation (standard PTA technique) can be performed.
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