====== Stent-Assisted Coiling for Unruptured Intracranial Aneurysm ====== Stent-assisted coiling may improve angiographic results of endovascular treatment of unruptured intracranial aneurysms compared with coiling alone, but this has never been shown in a randomized trial. Materials and methods: The Stenting in the Treatment of Aneurysm Trial was an investigator-led, parallel, randomized (1:1) trial conducted in 4 university hospitals. Patients with intracranial aneurysms at risk of recurrence, defined as large aneurysms (≥10 mm), postcoiling recurrent aneurysms, or small aneurysms with a wide neck (≥4 mm), were randomly allocated to stent-assisted coiling or coiling alone. The composite primary efficacy outcome was "treatment failure," defined as initial failure to treat the aneurysm; aneurysm rupture or retreatment during follow-up; death or dependency (mRS > 2); or an angiographic residual aneurysm adjudicated by an independent core laboratory at 12 months. The primary hypothesis (revised for slow accrual) was that stent-assisted coiling would decrease treatment failures from 33% to 15%, requiring 200 patients. Primary analyses were intent to treat. Results: Of 205 patients recruited between 2011 and 2021, ninety-four were allocated to stent-assisted coiling and 111 to coiling alone. The primary outcome, ascertainable in 203 patients, was reached in 28/93 patients allocated to stent-assisted coiling (30.1%; 95% CI, 21.2%-40.6%) compared with 30/110 (27.3%; 95% CI, 19.4%-36.7%) allocated to coiling alone (relative risk = 1.10; 95% CI, 0.7-1.7; P = .66). Poor clinical outcomes (mRS >2) occurred in 8/94 patients allocated to stent-assisted coiling (8.5%; 95% CI, 4.0%-16.6%) compared with 6/111 (5.4%; 95% CI, 2.2%-11.9%) allocated to coiling alone (relative risk = 1.6; 95% CI, 0.6%-4.4%; P = .38). Conclusions: The STAT trial did not show stent-assisted coiling to be superior to coiling alone for wide-neck, large, or recurrent unruptured aneurysms ((Boisseau W, Darsaut TE, Fahed R, Drake B, Lesiuk H, Rempel JL, Gentric JC, Ognard J, Nico L, Iancu D, Roy D, Weill A, Chagnon M, Zehr J, Lavoie P, Nguyen TN, Raymond J. Stent-Assisted Coiling in the Treatment of Unruptured Intracranial Aneurysms: A Randomized Clinical Trial. AJNR Am J Neuroradiol. 2023 Mar 16. doi: 10.3174/ajnr.A7815. Epub ahead of print. PMID: 36927759.)) ---- Stent-assisted coiling achieved better complete occlusion rates of aneurysms at 6 months or later after the procedure compared to [[balloon assisted coiling]], without being associated with a higher risk of intraprocedural complications and retreatment ((Wang F, Chen X, Wang Y, Bai P, Wang HZ, Sun T, Yu HL. Stent-assisted coiling and balloon-assisted coiling in the management of intracranial aneurysms: A systematic review & meta-analysis. J Neurol Sci. 2016 May 15;364:160-6. doi: 10.1016/j.jns.2016.03.041. Epub 2016 Mar 25. PubMed PMID: 27084238.)). Stent-assisted coiling (SAC) and balloon-assisted coiling (BAC) were alternative techniques developed to deal with complex aneurysms, but studies have shown their less than expected efficacy given their high rate of recanalization ((Shapiro M, Becske T, Sahlein D, Babb J, Nelson PK. Stent-supported aneurysm coiling: a literature survey of treatment and follow-up. AJNR Am J Neuroradiol (2012) 33(1):159–63.10.3174/ajnr.A2719)) ((Coley S, Sneade M, Clarke A, Mehta Z, Kallmes D, Cekirge S, et al. Cerecyte coil trial: procedural safety and clinical outcomes in patients with ruptured and unruptured intracranial aneurysms. AJNR Am J Neuroradiol (2012) 33(3):474–80.10.3174/ajnr.A2836)) ((White PM, Lewis SC, Gholkar A, Sellar RJ, Nahser H, Cognard C, et al. Hydrogel-coated coils versus bare platinum coils for the endovascular treatment of intracranial aneurysms (HELPS): a randomised controlled trial. Lancet (2011) 377(9778):1655–62.10.1016/S0140-6736(11)60408-X)) ((Piotin M, Pistocchi S, Bartolini B, Blanc R. Intracranial aneurysm coiling with PGLA-coated coils versus bare platinum coils: long-term anatomic follow-up. Neuroradiology (2012) 54(4):345–8.10.1007/s00234-011-0870-2 )). ===== Stent-assisted coiling for wide-neck intracranial aneurysm ===== [[Stent-assisted coiling for wide-neck intracranial aneurysm]]. ===== Dual stent-assisted coil embolization ===== [[Dual stent-assisted coil embolization]]. ===== Middle cerebral artery aneurysm Stent-assisted coiling ===== see [[Middle cerebral artery aneurysm Stent-assisted coiling]]. ===== Case series ===== [[Stent-assisted coiling case series]]. ====In vitro simulator==== There are several complications associated with Stent-assisted Coil Embolization (SACE) in cerebral aneurysm treatments, due to damaging operations by surgeons and undesirable mechanical properties of stents. Therefore, it is necessary to develop an in vitro simulator that provides both training and research for evaluating the mechanical properties of stents. A new in vitro simulator for three-dimensional digital subtraction angiography was constructed, followed by aneurysm models fabricated with new materials. Next, this platform was used to provide training and to conduct photoelastic stress analysis to evaluate the SACE technique. The average interaction stress increasingly varied for the two different stents. Improvements for the Maximum-Likelihood Expectation-Maximization method were developed to reconstruct cross-sections with both thickness and stress information. The technique presented can improve a surgeon's skills and quantify the performance of stents to improve mechanical design and classification. This method can contribute to three-dimensional stress and volume variation evaluation and assess a surgeon's skills ((Shi C, Kojima M, Tercero C, Najdovski Z, Ikeda S, Fukuda T, Arai F, Negoro M. In vitro simulator with numerical stress analysis for evaluation of stent-assisted coiling embolization in cerebral aneurysm treatments. Int J Med Robot. 2014 Dec;10(4):505-15. doi: 10.1002/rcs.1563. Epub 2013 Dec 27. PubMed PMID: 24375971. )).