Aneurysm embolization grade: a predictive tool for aneurysm recurrence after coil embolization
- 743 Downloads
Coil embolization has gained importance in the management of intracranial aneurysms over the past decade. However, the recurrence risk after embolization mandates closer follow-up than surgical clip ligation. Currently, there is no reliable system for predicting aneurysm sac thrombosis. An aneurysm embolization grade (AEG) reported previously by the senior author (EMD) has been proposed as a tool for predicting the durability of aneurysm occlusion based on hemodynamic characteristics. Here, we present our internal validity results.
AEG and Raymond–Roy Occlusion Classification (RROC) scores were prospectively assigned to all aneurysms coiled from June 2008 to June 2011. The prospectively assigned AEG and RROC scores from the cerebral angiograms were collected for data analysis and validity assessment of the AEG system. 110 consecutive patients who had aneurysm coil embolization were included in this study.
The post-coiling AEG significantly predicted follow-up angiographic filling characteristics. Pairwise comparisons revealed that the follow-up AEG for those initially scored ‘A’ (complete obliteration) was significantly better than the contrast-flow groups. Significant differences were also noted between contrast-stasis and contrast-flow groups. A pairwise comparison between RROC scores demonstrated that only the RROC Type 1 could be used to predict follow-up occlusion durability. Stent placement in wide-neck aneurysms had no effect on initial AEG, RROC, or long-term occlusion durability. Packing density significantly predicted initial AEG and RROC, but had no effect on long-term occlusion.
The AEG system is uniquely based on angiographic filling characteristics of the aneurysm, and this study demonstrated its high predictive value for determining aneurysm sac thrombosis. Assigning an AEG to the aneurysm can guide the neurointerventionalist in discussions with the patient regarding the probability of aneurysm recurrence and potential need for retreatment.
KeywordsAneurysm Coils Embolization Occlusion Recurrence
The authors would like to thank Margaret Riordan (Department of Neurosurgery, SUNY Upstate Medical University, Syracuse NY) and Sarah Dewitt (Department of Neurosurgery, SUNY Upstate Medical University, Syracuse NY) for their assistance with the collection of data for this manuscript.
Conflicts of interest
Eric M. Deshaies is a Physician Consultant for eV3/Covidien, Integra, and Microvention.
- 4.Gaba RC, Ansari SA, Roy SS, Marden FA, Viana MAG, Malisch TW (2006) Embolization of intracranial aneurysms with hydrogel-coated coils versus inert platinum coils: effects on packing density, coil length and quantity, procedure performance, cost, length of hospital stay, and durability of therapy. Stroke 37:1443–1450PubMedCrossRefGoogle Scholar
- 11.Molyneux AJ, Kerr RSC, Yu L-M, Clarke M, Sneade M, Yarnold JA, Sandercock P, International Subarachnoid Aneurysm Trial (ISAT) Collaborative Group (2005) International subarachnoid aneurysm trial (ISAT) of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms: a randomised comparison of effects on survival, dependency, seizures, rebleeding, subgroups, and aneurysm occlusion. Lancet 366:809–817PubMedCrossRefGoogle Scholar