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Year : 2019  |  Volume : 67  |  Issue : 6  |  Page : 1480--1481

Commentary on An Institutional Retrospective Study of Coil Loop Herniation and Its Management

Gaurav Goel, Anshu Mahajan 
 Department of Neurosciences, Medanta, The Medicity, Gurugram, Haryana, India

Correspondence Address:
Dr. Gaurav Goel
Department of Neurosciences, Medanta, The Medicity, Gurugram - 122 001, Haryana

How to cite this article:
Goel G, Mahajan A. Commentary on An Institutional Retrospective Study of Coil Loop Herniation and Its Management.Neurol India 2019;67:1480-1481

How to cite this URL:
Goel G, Mahajan A. Commentary on An Institutional Retrospective Study of Coil Loop Herniation and Its Management. Neurol India [serial online] 2019 [cited 2020 Feb 23 ];67:1480-1481
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Full Text

Despite the technical advances in the detachable coils for the treatment of intracranial aneurysm, technical complications, especially herniation of coil in the parent artery still occurs. This can lead to parent vessel occlusion and thromboembolic complications if not managed immediately and properly.[1] This complication is more commonly seen with the endovascular treatment of a wide-neck aneurysm and with the narrow-neck aneurysm occasionally. To prevent this, the stable basket should be achieved by using appropriate, longer, and stiffer first coil followed by shorter and softer coils later.[2] Various bailout strategies to deal with this feared complication have been described in the literature including balloon remodelling, stent remodelling, manual aspiration and several types of snares, merci devices, stentrievers, and alligator clamps.[1],[2],[3],[4] Microsurgical extraction of the coil has also been described in the literature in case of failed endovascular removal. However, all these endovascular techniques of coil retrieval can result in more intimal damage and further thromboembolic complication and also further increases the cost of the procedure.[4] We congratulate the authors of “An institutional retrospective study of coil loop herniation and its management” for describing specific rescue strategies according to proper selection criteria.[6] The authors are to be commended for the thoughtful way of describing the three bailout strategies for coil prolapse. Coil prolapse is more commonly seen during the placement of the final coils, but it can also occur during the first coil placement, especially in case of a small aneurysm.[3] Small coil prolapse with no evidence of any vessel occlusion and thromboembolism can be managed by anticoagulation and antiplatelet therapy.[3],[4] The stability and positioning of microcatheter is a key factor for successful coiling without intraprocedural complication. Therefore, it is recommended to use preshaped or adopted-shaped microcatheter to achieve intraaneurysmal stability of microcatheter, which may decrease the chance of coil prolapse.[5] The blank roadmap image can be created with the balloon inflation and deflation which can detect the subtle shift of coil loop and coil mass. If it is evident, it can be repositioned by readjustment of the remaining coil, by balloon inflation and subsequent insertion of additional coils that can displace the loops of previously inserted coils.[3] The third rescue technique although very effective, described to tackle the protrusion of coil loop using the stent for trapping should be cautiously used in the acutely ruptured aneurysms cases which require the administration of anticoagulation and dual antiplatelet therapy (DAT) especially, if the aneurysm starts filling after the coil protrusion which may increase the risk of re-rupture. Sometimes this may also further complicate, with multiple issues such as extra ventricular drain (EVD) placement, ventriculoperitoneal (VP) shunting and craniotomy for decompression, and hematoma evacuation being required in these patients, as the complication with bailout stent strategy was not anticipated before the start of the procedure. This is a worthwhile contribution from the authors for describing the bailout strategies for coil prolapse. However, the experience of the neuro interventionist is always critical to the final outcome.


1Yoo E, Kim DJ, Kim DI, Lee JW, Suh SH. Bailout stent deployment during coil embolization of intracranial aneurysms. AJNR Am J Neuroradiol 2009;30:1028-4.
2Luo CB, Chang FC, Teng MM, Guo WY, Chang CY. Stent management of coil herniation in embolization of internal carotid aneurysms. AJNR Am J Neuroradiol 2008;29:1951-5.
3Ding D, Liu KC. Management strategies for intraprocedural coil migration during endovascular treatment of intracranial aneurysms. J Neurointerv Surg 2014;6:428-31.
4Ishihara H, Ishihara S, Niimi J, Neki H, Kakehi Y, Uemiya N, et al. Risk factors for coil protrusion into the parent artery and associated thrombo-embolic events following unruptured cerebral aneurysm embolization. Interv Neuroradiol 2015;21:178-83.
5Kwon BJ, Im SH, Park JC, Cho YD, Kang HS, Kim JE, et al. Shaping and navigating methods of microcatheters for endovascular treatment of paraclinoid aneurysms. Neurosurgery 2010;67:34-40.
6Bishnoi I, Ohshima T, Ishikawa K, Yamamoto T, Goto S, Kato Y. An Institutional Retrospective Study of Coil Loop Herniation and its Management. Neurol India 2019;67:1474-9.