J Cerebrovasc Endovasc Neurosurg.  2022 Mar;24(1):58-62. 10.7461/jcen.2021.E2021.03.005.

Acute frame coil migration during filling coil retrieval in a cerebral aneurysm embolization case: A possible result of a venturi effect?

• Doron O
• Meirowitz E
• Abergel E

• KMID: 2527596
• DOI: http://doi.org/10.7461/jcen.2021.E2021.03.005

Abstract

Coil migration is a known complication of endovascular coiling of cerebral aneurysms. We report an acute coil migration occurring during coiling of an unruptured anterior choroidal aneurysm, while a separate coil was retrieved into the microcatheter concomitantly without direct contact between the coils. The “pulling” of a previously deployed stable coil is presented as an adverse effect that should be noted. This case exemplifies that not only direct entanglement or erroneous malposition can generate acute migration, but possibly, also alteration of physical forces during coil retrieval. A potential mechanism, similar to a venturi effect, caused by a quick suction within the microcatheter at its distal end, is suggested, and the clinical relevance of the case is discussed.

Keyword

Cerebral aneurysm; Coil migration; Venturi effect; Endovascular techniques

Figure

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  Fig. 1. (A) CT angiography on admission showing multiple aneurysms. (B) DSA showing left lateral ICA wall and Pcomm aneurysms as well as M1-2 aneurysm. (C) Right carotid injection revealing the right carotid terminus aneurysm. CT, computed tomography; DSA, diagnostic subtraction angiography; ICA, internal carotid artery; Pcomm, posterior communicating.

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  Fig. 2. (A) Rotational 3D imaging showing the relationship between the Pcomm and the anterior choroidal aneurysms. (B) Pcomm aneurysm blebs secured, as coiling of the anterior choroidal aneurysm is taking place with frame coil buildup. (C) Balloon assisted coiling of the aneurysm. Pcomm, posterior communicating.

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  Fig. 3. (A) Filling coil is retrieved into the microcatheter. Note a slight protrusion of the frame coil at the base of the aneurysm neck. (B) As the coil is further retrieved, simultaneous migration of the frame coil occurs into the catheter lumen. Notice the distance between the filling coil being retrieved and the frame coil, with a clear separation in between. (C) Using the balloon to stabilize further protrusion (see yellow arrow indicating coil protrusion in lateral ICA projection) and to redirect the frame coil free end back into aneurysm sac, a small loop is left adherent to the parent vessel lumen. (D) CT angiography showing final result. ICA, internal carotid artery; CT, computed tomography.

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  Fig. 4. Venturi effect as a suggested mechanism promoting destabilization of the frame coil within the sac. By suction effect created locally by retrieving the coil within the microcatheter, creates vacuum at the relative narrowing site between catheter’s tip and the vessel lumen, which may disrupt frame coil initial position.

Reference

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