AneurysmBalloon-expandable stenting with and without coiling for wide-neck and complex aneurysms
Introduction
Subarachnoid hemorrhage from intracranial aneurysm rupture accounts for less than 8% of all strokes, but has a disproportional impact because of its relatively young age of onset and poor outcomes, which renders it comparable to cerebral infarction in terms of loss of productive life years [7], [23]. It is potentially associated with lifestyle modifications, particularly in women, as it is associated with smoking, hypertension, and excessive alcohol intake [7], [8]. The data on treatment of most of these aneurysms are unusually robust. An international, prospective, randomized trial of endovascular coiling versus surgical clipping composed of more than 2000 patients with ruptured aneurysms, for which there was equipoise for either treatment, showed a significant 7.4%, absolute 1-year disability-free survival advantage, favoring coiling, which has persisted for 7 years [20]. The results are thought to be pertinent, by implication, to treating unruptured aneurysms, but the necessity for equipoise caused middle cerebral artery (prevailing opinion—surgery) and posterior circulation aneurysms (prevailing opinion—coiling) to be underrepresented and, hence, probably beyond the purview of the study's generalizeability [4].
Although not specifically stated, wide-neck (>4 mm neck or dome-to-neck ratio <2) aneurysms and fusiform aneurysms, which were problematic for both treatments, were typically not included [19]. The geometry of both is unfavorable for coil retention, hazarding protrusion into the parent artery, and, potentially, embolization [22]. Several strategies have been put forth for managing this hazard, but stenting of the parent vessel and then filling the aneurysm with coils through the stent's interstices, “stent-assisted coiling,” appears to be the most adaptable strategy [2], [6], [10], [11], [12], [13], [14], [15], [17], [18]. Initially, this was done with balloon-expandable stents designed for coronary arteries, but the recent trend has been to use self-expanding stents with their lesser radial strength. There are at least 4 reports of 95% or higher technical success [2], [10], [13], [17]. We have differed and have chosen to use the coronary artery, balloon-expandable, Lekton and subsequently available Lekton Motion stent system (Biotronik, AG, Bülach, Switzerland) for low-retentive-geometry aneurysms to achieve permanent aneurysm-parent-vessel junction remodeling and/or coil retention. We prefer this stent system because of its ease of navigation; its open structure facilitating coil delivery and coil retention; its ability to remodel the aneurysm entrance; its easily visualized markers; its limited shortening during expansion; and its smooth, antithrombogenic coating shown in in vitro and in vivo studies [11].
Section snippets
Patients
This was a longitudinal multicenter, observational study held at 4 centers throughout Brazil and Mexico. Between January 2003 and November 2005, 36 patients were recruited into the study. Patients were included if they had an incidental wide-neck or fusiform aneurysm (n = 14) or if they had bled within the previous 7 days (n = 12) and were willing and capable of giving informed consent in accordance with the treaty of Helsinki and laws of the respective countries. There were 26 women (72%) and
Technical failures
We defined the inability to navigate the device to the site of the aneurysm as a technical failure. Navigation of the balloon-expandable stent could not be accomplished in 2 patients. A second attempt with a self-expanding stent (Neuroform, Boston Scientific) was also not possible. Both aneurysms were located in the ophthalmic segment of the internal carotid artery and were successfully coiled using temporary balloon remodeling. These patients were counted as technical failures but were not
Discussion
Several strategies have been devised to improve immediate and permanent coil retention in wide-necked aneurysms. In 1997, Moret et al [21] introduced a technique using balloon remodeling of the parent artery, temporarily blocking the neck during coiling of the sac. Soon thereafter, 3D Guglielmi coils that expand into a basket shape with loops at 90° angles [3] were developed. The next logical step was to combine 3D coiling and temporary balloon remodeling, accepting a small but definite risk of
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Updates in the Management of Cerebral Infarctions and Subarachnoid Hemorrhage Secondary to Intracranial Arterial Dissection: A Systematic Review
2019, World NeurosurgeryCitation Excerpt :These factors promote thrombosis of the aneurysm and lead to the occlusion of the aneurysm and neointimal growth over the stent scaffold. Several studies have been reported71-77 showing the safety and efficacy of stenting in reconstructing dissected vessels. The procedure also has a lower risk of aneurysm rupture, because no coils are inserted into the thin-walled lesions.
Endovascular Management of Microcerebral Aneurysms with Diameter Smaller than 3 mm: Is It Feasible and Safe?
2018, Journal of Stroke and Cerebrovascular DiseasesCitation Excerpt :Doerfler et al10 suggested that double-stenting represent a therapeutic alternative, especially in cases of microwide-necked aneurysms with unsuitable coil embolization strategy. Because of such double-stenting association with a higher risk of intimal hyperplasia and medical cost in some countries as well as ours,23 we cannot advocate such approach. Early and careful follow-up angiography is necessary for these unsecured aneurysms.
The combined approach to intracranial aneurysm treatment
2009, Surgical NeurologyCitation Excerpt :Recent innovations in endovascular technology, including enhanced coil construction, intracranial stents, balloon remodeling, and the 2-catheter technique, have led to rapid advances in minimally invasive aneurysm treatment [7,28,44,64,67]. It is currently possible to treat even complex intracranial aneurysms both surgically and endovascularly using a wide variety of techniques and devices [39,67]. As current technologies progress, however, endovascular innovation promises to continue its expansion.
Re-treatment of patients with embolized ruptured intracranial aneurysms
2008, Surgical NeurologyCitation Excerpt :Accelerated clot maturation would anchor the coils in place, seal the aneurysmal neck, and facilitate aneurysm retraction as the coils are absorbed through a local inflammatory response. Balloon remodeling and stent-assisted coil embolization techniques have been applied to treat broad-based unruptured aneurysms, and these methods were reportedly useful in addressing recurrent aneurysms [11,28]. The additional treatment of previously coiled aneurysms is safe, and the strategy of regular follow-up is effective.
Endovascular treatment of very small intracranial aneurysms
2008, Surgical NeurologyCitation Excerpt :Doerfler et al [3] suggested that double-stent method may represent a therapeutic alternative, especially in cases of small, wide-necked aneurysms which are unsuitable for coil embolization. The choice of double-stent placement may also be influenced by worry of association with a higher risk of intimal hyperplasia and medical cost in some countries as well as ours [22]. Early and careful follow-up angiography is necessary for these unsecured aneurysms.