The Procedure

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Micrus MicroCoil Guide to Using the Frame and Fill Concept

It is important to size the first MicroCoil precisely to the aneurysm's diameter to take advantage of the following frame and fill concept:

Concept	Technique	Reasoning
Frame Spherical MicroCoils	Match MicruSphere to aneurysm: •Equal to the diameter of the aneurysm • greater than neck diameter Deploy Spherical MicroCoil	Do not over size • To frame precisely • To prevent migration To form basket-shape
Fill Helical MicroCoils	Deploy progressively smaller HeliPaq™ MicroCoils	To occlude aneurysm

Embolization Procedure
All Neuroradiology teams typically follow the same embolization procedure:

1. Evaluate the aneurysm radiologically
2. Position a commercially available microcatheter at mouth of aneurysm
3. Feed MicroCoil System through the microcatheter
   • Deploy 1st coil: spherical shape and sized to match the aneurysm's
    diameter to form a basket-shaped frame within the aneurysm. In
    aneurysms > 4 mm, a second spherical coil (one size smaller) is
    usually deployed to strengthen the frame.
   • Deploy subsequent coils: helical shape (each, progressively smaller
    in size) to fill aneurysm. (Note: Micrus is compatible with all other coils
    on the market at this time.)
5. Evaluate degree of aneurysm occlusion
6. End of procedure.