10
spin echo and gradient echo pulse sequence in a MR 3.0 Tesla system (General
Electric Healthcare Excite, HDx). Therefore, it may be necessary to optimize
MR imaging parameters for the presence of this metallic embolization coil.
For US Patients Only
Cook recommends that the patient register the MR conditions disclosed in
this IFU with the MedicAlert Foundation. The MedicAlert Foundation can be
contacted in the following manners:
Mail:
MedicAlert Foundation International
2323 Colorado Avenue
Turlock, CA 95382
Phone: 888-633-4298 (toll free)
209-668-3333 from outside the US
Fax:
209-669-2450
Web: www.medicalert.org
INSTRUCTIONS FOR USE
1. Perform an angiogram and measure the diameter of the vessel to be
occluded.
2. Firmly grasping the loading cartridge between thumb and forefinger,
introduce the metal end of the loading cartridge into the base of the
catheter hub. Lock the loading cartridge onto the catheter hub by turning
the Luer lock adapter clockwise. (Fig. 3)
3. Unlock the white safety clip and advance at least 30 cm of the delivery
wire into the catheter so that the coil is fully loaded in the catheter.
(Fig. 4)
4. Unlock the loading cartridge from the catheter hub by turning the Luer
lock adapter counter-clockwise.
5. Remove the delivery wire holder and the metal loading cartridge from
the catheter hub while holding the delivery wire stationary. Remove the
torque device and reserve it for use later in the procedure.
6. Under fluoroscopic visualization, slowly advance the delivery wire until
the entire length of the coil exits the distal end of the catheter. Ensure
that the junction remains positioned just inside the catheter tip. (Fig. 5)
NOTE: Advancing the delivery wire slowly allows the junction to be seen
more easily and reduces the risk of damaging it.
NOTE: If significant resistance is encountered during coil advancement,
do not continue advancing. Retract the delivery wire slightly, then gently
re-advance it. If there is still significant resistance, withdraw the delivery
wire from the catheter and try using a new coil with a shorter length.
NOTE: Do not turn the delivery wire counterclockwise during
advancement; the coil may be unintentionally detached.
7. Verify correct position of the coil fluoroscopically. If coil position or
placement is not satisfactory, the coil may be retracted into the catheter
and re-deployed so long as there is no significant resistance.
NOTE: It may be possible to perform a test injection of contrast media
using a Tuohy-Borst Sidearm Adaptor while the delivery wire is in the
catheter.
NOTE: If the size of the coil is not correct, gently remove the entire
delivery wire and coil. Do not use the coil again.
8. If the coil position is correct, use the torque device to turn the delivery
wire counterclockwise 8-10 times, until coil detachment can be either felt
or visualized under fluoroscopy. (Fig 6)
NOTE: It is recommended that the junction remain just inside the tip of
the catheter.
NOTE: Do not advance the delivery wire after the coil is detached.
9. Gently remove the delivery wire after coil detachment.
10. Additional Retracta or pushable coils may be required to achieve
permanent occlusion of the vessel.
Coil Delivery Technique and Coil Size Selection
Long-term occlusion depends on achieving cross sectional occlusion of the
blood vessel, and coaxial catheters provide the ability to control placement
of coils and permanent occlusion. The combination of the coaxial technique
and either the anchor or scaffold technique significantly enhances stability of
coil deployment.
• Coaxial technique: The use of outer guiding sheath/catheter is the most
important step in preventing coil elongation and uncertain long-term
occlusion. The outer guiding sheath/catheter provides support, and the
inner catheter provides finer selective maneuvers. (Fig. 7)
• Anchor technique: The anchor technique provides safe and distal
occlusion when there is a question about instability of coils. At least 2 cm
of a coil is advanced into the side branch, which is normally sacrificed.
The rest of the coil is then deployed just proximal to that side branch, and
additional coils are packed. (Fig. 8)
• Scaffold technique: The scaffold technique is used for high-flow vessels
when there is concern about migration of a softer coil. A high radial force
coil is placed initially. Then, several high radial force coils or soft coils may
be packed within the scaffold. (Fig. 9)
