| Article Access Statistics|
| Viewed||3044 |
| Printed||105 |
| Emailed||1 |
| PDF Downloaded||77 |
| Comments ||[Add] |
| Cited by others ||6 |
Click on image for details.
|Year : 2012 | Volume
| Issue : 3 | Page : 278-282
Stent-assisted coil embolization of intracranial aneurysms using Solitaire stent
Jingbo Zhang, Xianli Lv, Jun Yang, Zhongxue Wu
Interventional Neuroradiology Department, Beijing Neurosurgical Institute and Beijing Tiantan Hospital, Capital Medical University, Beijing, China
|Date of Submission||06-Mar-2012|
|Date of Decision||05-Apr-2012|
|Date of Acceptance||29-Apr-2012|
|Date of Web Publication||14-Jul-2012|
Beijing Neurosurgical Institute, No.6, Tiantan Xili, Chongwen, Beijing, 100050
Source of Support: None, Conflict of Interest: None
Objective: To report patients with intracranial wide-necked or complex aneurysms who underwent Solitaire stent-assisted coil embolization. Materials and Methods: Retrospective analysis of 28 patients with intracranial wide-necked or complex aneurysms. Eighteen of the patients presented with an acute subarachnoid hemorrhage. Thirty-one aneurysms were treated with the support of different applications (n = 32) of the Solitaire AB stents followed by the standard coiling procedure (n = 30). Results: Successful positioning of the remodeling device was obtained in all the cases. One stent required repositioning after full deployment. There were four thromboembolic complications (12.5%) and two hemorrhagic complications (6.25%), which caused three deaths. No permanent procedural morbidity was observed in the surviving patient. Angiographic results included 26 complete occlusions (83.9%), three neck remnants (9.7%) and two incomplete occlusions (6.4%). Conclusion: Although the initial technical and clinical results of Solitaire stent-assisted coiling of aneurysms was reported to be encouraging in recent reports, we had encountered higher thromboembolic and hemorrhagic complications in our patients.
Keywords: Complex, embolization, intracranial aneurysm, solitaire stent, wide-necked
|How to cite this article:|
Zhang J, Lv X, Yang J, Wu Z. Stent-assisted coil embolization of intracranial aneurysms using Solitaire stent. Neurol India 2012;60:278-82
| » Introduction|| |
A wide aneurysm neck (i.e., 4 mm or more) turned out to be the major limitation for the endovascular coil treatment of intracranial aneurysms. ,, Stent-assisted coil embolization has shown the safety and efficacy for such complex aneurysms. During the last decade, neurovascular remodeling devices from Neuroform stent (Smart Therapeutics, acquired by Boston Scientific) to Enterprise stent (Codman Neurovascular) became widely used and generally accepted for the endovascular treatment of intracranial aneurysms. Among the available self-expandable stents, the Solitaire stent (EV3) is the most recent one. ,, Thrombectomy for acute ischemic stroke with Solitaire was anticipated early in the product history, and is proving to be very effective. ,, The aim of this study was to report patients with intracranial wide-necked or complex aneurysms who underwent Solitaire stent-assisted coil embolization.
| » Materials and Methods|| |
From June 2010 to September 2011, 28 patients with 31 aneurysms were treated by stent-assisted coiling with the Solitaire stent (EV3, Irvine, CA, USA). There were 16 women and 12 men, with a mean age of 49.9 years. Clinical presentation is detailed in [Table 1]. Ten patients had unruptured aneurysms. Seventeen patients presented with grade I subarachnoid hemorrhage (SAH).  One patient had a recanalized aneurysm after initial embolization. Prior to all procedures, patients underwent conventional angiography of both internal carotid arteries (ICA), vertebral arteries (VA) and a three-dimensional angiography. Aneurysm characteristics are detailed in [Table 1], and 29 aneurysms were wide-necked (neck >4 mm or dome/neck ratio <2) and two were dissecting.
|Table 1: Clinical data of patients treated with Solitaire stent-assisted coil embolation|
Click here to view
In 30 cases, endovascular management consisted of stent delivery across the aneurysm and its neck and subsequent coiling of the sac, and only one stent was placed in one case of dissection without aneurismal dilation. Medical premedication was initiated in all but one patient 3 days prior to the procedure with 100 mg of aspirin and 75 mg of clopidogrel per day. In patients who presented with SAH, a loading dose of 300 mg of clopidogrel was administered 2 h before treatment. Endovascular procedures were performed under general anesthesia and systemic heparinization. A baseline activated clotting time (ACT) was obtained prior to the bolus infusion of 3000 IU heparin, and hourly thereafter. The bolus infusion of heparin was followed by a continuous drip (1000 IU/h), with the purpose of doubling the baseline ACT. Systemic heparinization was not prolonged in all patients after embolization. Unilateral femoral access was obtained through a percutaneous femoral artery puncture and one 6-F guide catheter was inserted into the parent vessel. A Rebar microcatheter was then advanced over a 0.014″ Silverspeed microguidewire (EV3) into the normal distal artery beyond the aneurysm by 1-2 cm. Then, the coiling catheter was navigated within the aneurysmal sac in order to jail it with the stent. The stent was introduced into the hub of the Rebar catheter and was then pushed through the microcatheter and aligned directly across the neck of the aneurysm. When proper alignment was achieved, the microcatheter was gently pulled back to unsheath the stent, while forward tension was maintained on the stent system to keep it in place. We always waited for the distal markers to be completely open and then the stent was fully deployed and positioning was confirmed by direct visualization. If the stent required repositioning, it was resheathed, repositioned and then redeployed. Microplex coils (MicroVention, Aliso Vieja, CA, USA) or Axium coils (EV3) were delivered via the second catheter into the aneurysm [Figure 1] and [Figure 2]. After embolization, patients were transferred to the Intensive care unit, and fluid balance, neurological status and blood pressure were carefully monitored. Patients were maintained on dual antiplatelet agents, 75 mg clopidogrel daily and 100 mg aspirin daily for 1 month and aspirin (100 mg/day) for 6 months.
|Figure 1: A 40-year-old woman presented with a wide-necked basilar artery apex aneurysm and the bilateral posterior communicating arteries were small. She denied surgical clipping. After discussion of the treatment alternatives in detail, a Y-stent reconstruction technique using two Solitaire stents was thought to offer the chance for treatment of this aneurysm (a) The left vertebral injection, anteroposterior view, showing the aneurysm (b) Fluoroscopic image shows Y-stent-supported reconstruction of the basilar apex aneurysm (c) Post-procedure angiography shows coil occlusion of the aneurysm|
Click here to view
|Figure 2: A 71-year-old female had an unruptured ophthalmic internal carotid artery (ICA) aneurysm. (a) Three-dimensional reconstruction of the right ICA injection revealed a large aneurysm arising from the ophthalmic segment with proximal torture (b) Post-embolization angiogram demonstrated nearly-complete occlusion of the aneurysm after Solitaire stent-assisted coiling|
Click here to view
Angiographic and clinical results
Patients were evaluated by angiography at the end of the procedure to document aneurysm obliteration. Angiographic results were classified as complete occlusion (no contrast filling the aneurysmal sac), neck remnant (residual contrast filling the aneurysmal neck) and incomplete occlusion (residual contrast filling the aneurysmal body). Angiography and clinical follow- up were obtained at 3-13 months (mean 5.8 months). A senior neurointerventionalist recorded the clinical course, including worsening of symptoms and death. Clinical outcome was graded according to a modified Rankin Scale (mRS). 
| » Results|| |
Aneurysm size and neck size
Of the 31 treated aneurysms, 28 (90.3%) were less than 15 mm in size, one (3.2%) was 15-25 mm and two (6.5%) were larger than 25 mm. Fifteen aneurysms (48.4%) had necks measuring 4 mm or less, 14 (45.4%) had wide necks and two aneurysms (6.5%) were dissecting.
Twenty-five (80.6%) of the 31 aneurysms were located in the anterior circulation, one at the A1 segment of the anterior cerebral artery (ACA), four at the ophthalmic segment of the internal carotid artery (ICA), four at the cavernous segment of the ICA, three at the anterior communicating artery (Acoma), three at the middle cerebral artery (MCA) and 10 at the ICA-posterior communicating artery (Pcoma) junction. Six aneurysms were located in the posterior circulation, three at the basilar artery (BA) apex and three at the vertebral artery-inferior cerebellar artery complex (VA-PICA).
Stent deployment was successful in all the aneurysms. Selective embolization was successfully performed in all but one patient. In one patient with a dissection of vertebral artery without aneurysmal dilation, stent placement was only performed. Y-stent reconstruction technique using two Solitaire stents was performed for a BA apex aneurysm. Angiographic results included 26 complete occlusions (83.9%), three neck remnants (9.7%) and two incomplete occlusions (6.4%).
Four thromboembolic complications (12.5%) were encountered after Solitaire stent deployment when the aneurysmal sac was filled with coils [Table 1]. Local intra-arterial administration of urokinase completely resolved the thrombus without any clinical deficits in three patients, and one patient died of intracranial hemorrhage after thrombolysis. Two delayed intracranial hemorrhages (6.25%), which were not located at the aneurysmal locations, caused two deaths. The cause of the bleeding remains speculative.
Clinical and angiographic follow-up examinations were performed in 23 (82.1%) patients for 24 aneurysms after a mean time of 7.6 months (range 3-13 months). Five patients are waiting for an angiographic follow-up, but assessment of the mRS scale was performed by telephone interview. Twenty-one lesions were unchanged (complete occlusion in 18, residual neck in three and no occlusion in one). One aneurysm exhibited increase in the spontaneous thrombosis after stent deployment with coil embolization done 3 months before. Two (6.5%) recurrences were evident. Subsequently, all of these were completely occluded by coil embolization. The clinical status was mRS = 0 in the surviving 25 patients, and showed resolution of periprocedural deficits in two patients.
| » Discussion|| |
The feasibility and efficacy of stent-assisted coiling in complex intracranial aneurysms has been well described. ,, The first self-expandable intracranial stent is the Neuroform stent (Boston Scientific, Fremont, CA, USA), with proven efficacy and safety, and the procedure-related morbidity-mortality rates were low. ,,, However, the Neuroform stent presents some limiting characteristics, including the impossibility to reposition it when it is partially delivered, a low radial force and some deployment difficulties. ,,, Therefore, new stents have recently been developed to circumvent these limitations. The first retractable stent to be released was the Leo stent, and its limiting characteristic is the need for progressively larger and stiffer delivery catheters to place larger stents. ,, The second retractable and recently released stent is the Enterprise stent, which has been evaluated to be the easiest to navigate. ,, Although some authors report its limitation of poor visibility,  we did not encounter this problem in our center. The Solitaire stent is the first stent that is fully retractable. ,, In our opinion, almost all stents are easy to place and are similar in terms of navigability, including the new generation of Neuroform, which is now delivered through a microcatheter. In terms of precision, Solitaire is the one that can be more precisely place and deployed. The Leo stent has been evaluated in our center, and has shown the major advantage of this retrievability.  Moreover, of the 28 aneurysms treated, there were two stent placement failures and 10.7% thromboembolic complications in that series.
The first generation of Solitaire stent, the so-called SOLO stent (EV3), has already been evaluated in two series. , Very recently, Klisch et al.  reported the first and only series of patients treated with the definitive version of the stent, the so-called Solitaire stent (EV3). These studies showed the safety and efficacy of the stent, and they did not show significant limitations. Even if our study confirms the advantages of this stent, it also pointed out some limitations that must be known when planning to treat patients with this device. First, the stent should be used with caution in the parent artery of a small artery with an acute angle. We would prefer to put an open-cell stent (Neuroform) in this situation. In the present series, we have experienced a significant slow reduction in both anterior cerebral arteries in a case of anterior communicating artery aneurysm, an acute angle was found at the A1 and A2 segments of the ACA. The aneurysm was incompletely embolized and the patient died of intracranial hemorrhage 6 h after treatment. This phenomenon might be related to the higher radial force of the stent when compared with the other available stents. Indeed, a high radial force might be an advantage in some situations (e.g., avoiding dislocation after placement, which has been reported more frequently for the Enterprise stent) or a disadvantage in some other situations, like extreme oversize of a stent-system resulting in permanent vasospasm. However, within these scenarios, a stent should always be used with caution - but retractability of a system is the main advantage to react in this fashion described before. The second limitation concerns the similar thromboembolic complication rate with the Leo stent, which seems to be higher than that of the Enterprise stent. , The third limitation is that an intrinsic hemodynamic effect of the Solitaire is apparently non-existing, mainly due to the large cell size.
In small vessels (<2.5 mm), we are using the Neuroform stent, which has many available diameters.  In large vessels (> 4 mm), we are using the 6-mm Solitaire stent and the Enterprise stent (4.5 mm in diameter) to avoid coil protrusion between the stent and the vessel wall. In medium-sized vessels (between 2.5 and 4 mm), the Enterprise and the Solitaire are the ones we are always choosing. The only available Enterprise stent diameter is 4.5 mm, and it has been successfully used in aneurysms located on a parent artery with a diameter greater than 4 mm or with a diameter between ≥3 and ≤4 mm. , Klisch et al. described 10 A1/Acoma and seven MCA aneurysms treated with Solitaire stent. We used 4 mm stents in A1, AComA and M2 (small parent artery) aneurysms in a 15-year old, where the parent vessel was patent on follow-up angiograms. Solitaire stent is a highly navigable tool in aneurysm treatment even in small vessels such as the M1-M2 segments of the MCA and the A1-A2 segments of the ACA, although a vessel diameter of 3-4 mm is recommended. Reconstructing vessel bifurcations by crossing stent-in-stent deployment (Y-configuration) is possible with the Solitaire, as shown in our patient. From a clinical and anatomical point of view, similar results as those published with this stent and with other available stents were obtained in our study. ,,,,,,,,,,, In our department, patient selection for endovascular treatment with self-expandable stent mostly includes unruptured intracranial aneurysm that cannot safely be treated by the use of the remodeling technique. On the other hand, our study reinforces the idea that stenting is improving, and stabilizing anatomical results of coiled aneurysms have recently been published in three series.  Pipeline device is a different concept and has different indications; its navigability, deployment and placement is not easy. Therefore, each stent has different properties that makes it more appropriate in different situations.
In conclusion, our preliminary study shows that a major advantage of the Solitaire stent is the possibility to fully retrieve the stent whenever necessary. Although the initial technical and clinical results of Solitaire stent-assisted coiling of aneurysms was reported to be encouraging in recent reports, we had encountered a higher thromboembolic and hemorrhagic complication in our patients.
| » References|| |
|1.||Benitez RP, Silva MT, Klem J, Veznedaroglu E, Rosenwasser RH. Endovascular occlusion of wide-necked aneurysms with a new intracranial microstent (Neuroform) and detachable coils. Neurosurgery 2004;54:1359-67. |
|2.||Lubicz B, Bandeira A, Bruneau M, Dewindt A, Balériaux D, De Witte O. Stenting is improving and stabilising anatomical results of coiled intracranial aneurysms. Neuroradiology 2009;51:419-25. |
|3.||Zhang J, Lv M, Lv X, Jiang C, Li Y, Wu Z. Endovascular treatment using stents for cerebral aneurysms. Neuroradiol J 2010;23:730-6. |
|4.||Lubicz B, Collignon L, Raphaeli G, Bandeira A, Bruneau M, De Witte O. Solitaire stent for endovascular treatment of intracranial aneurysms: Immediate and mid-term results in 15 patients with 17 aneurysms. J Neuroradiol 2010;37:83-8. |
|5.||Klisch J, Clajus C, Sychra V, Eger C, Strasilla C, Rosahl S, et al. Coil embolization of anterior circulation aneurysms supported by the Solitaire AB Neurovascular Remodeling Device. Neuroradiology 2010;52:349-59. |
|6.||Sychra V, Klisch J, Werner M, Dettenborn C, Petrovitch A, Strasilla C, et al. Waffle-cone technique with Solitaire AB Remodeling Device: Endovascular treatment of highly selected complex cerebral aneurysms. Neuroradiology 2010 Sep 7. [Epub ahead of print]. |
|7.||Huded V, Rajesh KN, Netravathi S, Iyer R. Endovascular treatment for acute ischemic stroke using solitaire stent: Temporary endovascular bypass, a novel technique. Neurol India 2011;59:401-4. |
|8.||Wehrschuetz M, Wehrschuetz E, Augustin M, Niederkorn K, Deutschmann H, Ebner F. Early single center experience with the solitaire thrombectomy device for the treatment of acute ischemic stroke. Interv Neuroradiol 2011;17:235-40. |
|9.||Castaño C, Dorado L, Guerrero C, Millán M, Gomis M, Perez de la Ossa N, et al. Mechanical thrombectomy with the Solitaire AB device in large artery occlusions of the anterior circulation: A pilot study. Stroke 2010;41:1836-40. |
|10.||Hunt W, Hess R. Surgical risk as related to time of intervention in the repair of intracranial aneurysms. J Neurosurg 1968;28:14-20. |
|11.||Bonita R, Beaglehole R. Modification of Rankin Scale: Recovery of motor function after stroke. Stroke 1988;19:1497-500. |
|12.||Wu Z, Lv X, Yang X, He H. Ruptured vertebro-inferoposterior cerebellar artery dissecting aneurysm treated with the Neuroform stent deployment and vertebral artery occlusion. Eur J Radiol Extra 2009;70: e100-3. |
|13.||Fiorella D, Albuquerque F, Han P, MacDougall C. Preliminary experience using the Neuroform stent for the treatment of cerebral aneurysms. Neurosurgery 2004;54:6-16. |
|14.||Lylyk P, Ferrario A, Pasbon B, Miranda C, Doroszuk G. Buenos Aires experience with the Neuroform self-expanding stent for the treatment of intracranial aneurysms. J Neurosurg 2005;102:235-41. |
|15.||Lv X, Li Y, Jiang C, Yang X, Wu Z. Potential advantages and limitations of the Leo stent in endovascular treatment of complex cerebral aneurysms. Eur J Radiol 2011;79:317-22. |
|16.||Kis B, Weber W, Berlit P, Kuhne D. Elective treatment of saccular and broad-necked intracranial aneurysms using a closed-cell nitinol stent (Leo). Neurosurgery 2006;58:443-50. |
|17.||Lubicz B, Leclerc X, Levivier M, Brotchi J, Pruvo JP, Lejeune JP, et al. Retractable self-expandable stent for endovascular treatment of wide-necked intracranial aneurysms: Preliminary experience. Neurosurgery 2006;58:451-7. |
|18.||Lv X, Li Y, Xinjian Y, Jiang C, Wu Z. Results of endovascular treatment for intracranial wide-necked saccular and dissecting aneurysms using the enterprise stent: A single center experience. Eur J Radiol 2011 May 4. [Epub ahead of print]. |
|19.||Lubicz B, François O, Levivier M, Brotchi J, Balériaux D. Preliminary experience with the Enterprise stent for endovascular treatment of complex intracranial aneurysms: Potential advantages and limiting characteristics. Neurosurgery 2008;62:1063-9. |
|20.||Mocco J, Snyder KV, Albuquerque FC, Bendok BR, Alan SB, Carpenter JS, et al. Treatment of intracranial aneurysms with the Enterprise stent: A multicenter registry. J Neurosurg 2009;110:35-9. |
|21.||Yavuz K, Geyik S, Pamuk AG, Koc O, Saatci I, Cekirge HS.Immediate and midterm follow-up results of using an electrodetachable, fully retrievable SOLO stent system in the endovascular coil occlusion of wide-necked cerebral aneurysms. J Neurosurg. 2007;107:49-55. |
|22.||Liebig T, Henkes H, Reinartz J, Miloslavski E, Kühne D. A novel self-expanding fully retrievable intracranial stent (SOLO): experience in nine procedures of stent-assisted aneurysm coil occlusion. Neuroradiology. 2006;48:471-8. |
[Figure 1], [Figure 2]
|This article has been cited by|
||Extraction of a migrated coil from the Enterprise stent strut using a Solitaire AB stent
| ||Huijian Ge,Hengwei Jin,Youxiang Li,Xianli Lv |
| ||The Neuroradiology Journal. 2016; 29(6): 470 |
|[Pubmed] | [DOI]|
||The Use of Solitaire AB Stents in Coil Embolization of Wide-Necked Cerebral Aneurysms
| ||Teng-Fei Li,Shao-Feng Shui,Xin-Wei Han,Lei Yan,Ji Ma,Dong Guo,Hong-Can Zhu,Shu-Kai Wang,Yuan-Hong He,Wen-Wu Chen,Li-Ping Wei,Ming-Ke Wang,Tai-Min Song,Alberto Aliseda |
| ||PLOS ONE. 2015; 10(10): e0139714 |
|[Pubmed] | [DOI]|
||Complications in Stent-Assisted Endovascular Therapy of Ruptured Intracranial Aneurysms and Relevance to Antiplatelet Administration: A Systematic Review
| ||C.- W. Ryu,S. Park,H. S. Shin,J. S. Koh |
| ||American Journal of Neuroradiology. 2015; 36(9): 1682 |
|[Pubmed] | [DOI]|
||Thromboelastography for monitoring platelet function in unruptured intracranial aneurysm patients undergoing stent placement
| ||H. Yang,Y. Li,Y. Jiang,X. Lv |
| ||Interventional Neuroradiology. 2015; 21(1): 61 |
|[Pubmed] | [DOI]|
||Outcomes of Stent-assisted Coil Embolization of Wide-necked Intracranial Aneurysms Using the Solitaire™ AB Neurovascular Remodeling Device
| ||Hae Woong Jeong,Won-Bae Seung |
| ||Journal of Cerebrovascular and Endovascular Neurosurgery. 2015; 17(4): 301 |
|[Pubmed] | [DOI]|
||Stent-assisted coiling of cerebral aneurysms using the Enterprise and the Solitaire devices
| ||Yong-An Chen,Mohammed Hussain,Jing-Yuan Zhang,Kun-Peng Zhang,Qi Pang |
| ||Neurological Research. 2014; 36(5): 461 |
|[Pubmed] | [DOI]|