Stent-assisted Technique Research Articles

Improved Endovascular Coiling of Wide-Neck Intracranial Aneurysms in Elderly Patients by Double-Microcatheter Technique.

Elderly patients are more susceptible to intracranial aneurysms. However, many of them are poor surgical candidates and often have to undergo endovascular treatment. The purpose of this study was to evaluate the efficacy and safety of double-microcatheter technique as an alternative to a balloon- or stent-assisted techniques for wide-neck aneurysms in elderly patients. A retrospective review of 58 patients with 58 wide-neck aneurysms treated with the double-microcatheter technique between October 2010 and December 2012 was performed. Immediate post-embolization angiograms were evaluated using a conventional angiographic scale, and clinical evaluation was performed using the Glasgow Outcome Scale. Clinical and imaging follow-ups were available in 32 (55%) patients, with a mean of 12.5 months. Post-embolization angiograms demonstrated total occlusion in 46 of 58 (79%) aneurysms, a neck remnant in 7 (13%), and body filling in 5 (8%). The technique-related complication rate was 5% (3/58), and the procedural-related mortality rate was 0. Of the 32 aneurysms with follow-ups, recanalization developed in 3 (9%) aneurysms, and none received re-treatment. Using double-microcatheter technique for embolization of wide-neck intracranial aneurysms is safe and effective in the elderly patients. This technique is feasible and safe for coil embolization of wide-neck aneurysms, especially in cases, which are not suitable for balloon- or stent-assisted techniques.

Endovascular treatment of acute intracranial vertebral artery dissection: long-term follow-up results of internal trapping and reconstructive treatment using coils and stents

BackgroundEndovascular internal trapping is an effective procedure for the treatment of acute vertebral artery dissection (VAD). However, the outcomes of reconstructive treatment have not been well established. The aim of...

Parent artery occlusion in large, giant, or fusiform aneurysms of the carotid siphon: clinical and imaging results.

Parent artery occlusion has long been considered the reference treatment for large/giant or fusiform aneurysms of the carotid siphon. However, meager recent data exist on this technique, which tends to be replaced by stent-assisted reconstructive techniques. In our department since 2004, we have assessed the safety, efficacy, and complication risk factors of parent artery occlusion by using coils for trapping these aneurysms. We determined retrospectively the complication rate, factors associated with the occurrence of an ischemic event, changes in symptoms of mass effect, evolution of the aneurysmal size, and the growth of an additional aneurysm after treatment. Fifty-six consecutive patients were included, with a median age of 54 years (range, 25-85 years; 92% women), 48% with giant aneurysms and 75% with infraclinoid aneurysms. There was a permanent morbidity rate of 5% exclusively due to ischemia, a zero mortality rate, an aneurysmal retraction rate of 91%, and an improvement rate for pain of 98% and for cranial nerve palsy of 72%, with a median follow-up of >3 years. Para-/supraclinoid topography of the aneurysm (P = .043) and the presence of cardiovascular risk factors (P = .024) were associated with an excessive risk of an ischemic event, whereas the presence of a mural thrombus had a protective role (P = .033). In this study, parent artery occlusion by using coils to treat large/giant or fusiform aneurysms of the carotid siphon was safe and effective, especially for giant infraclinoid aneurysms. According to recent meta-analyses, these results suggest that the validation of stent-assisted reconstructive treatments for these aneurysms requires controlled studies with parent occlusion artery.

Single-centre comparison of procedural complications, clinical outcome, and angiographic follow-up between coiling and stent-assisted coiling for posterior communicating artery aneurysms

Aneurysm recurrence is a principle limitation of endovascular coiling procedures, especially in posterior communicating artery aneurysms, with reported recurrence rates of >30%. The adjunctive use of self-expandable stents has revolutionised the treatment of intracranial aneurysms, especially for complex morphologies, wide necks, or unfavourable dome-to-neck ratios. However, there are limited data concerning a direct comparison between simple coiling and stent-assisted coiling in posterior communicating artery aneurysms. This study aimed to compare the durability and outcomes of coiling versus stent-assisted coiling procedures. Imaging data of patients with posterior communicating artery aneurysms treated with coiling or stent-assisted coiling between January 2008 and October 2012 were retrospectively analysed. The initial angiographic results, procedural complications, and clinical outcomes were assessed at discharge. Imaging follow-up was performed with cerebral angiography. Complete aneurysm occlusion was achieved on initial angiography in 23/56 (41.1%) stent and 83/235 (35.3%) non-stent patients. At the latest follow-up (mean follow-up 14.3±10.4months for stent and 13.2±9.5months for non-stent patients), aneurysms had recurred in 5/47 (10.6%) stent and 57/203 (28.1%) non-stent patients (p=0.014). Procedural complications occurred in 6/56 (10.7%) stent and 27/235 (11.5%) non-stent aneurysms. No rebleeding occurred during clinical follow-up (mean duration, 46.7months). Recurrence rates at the latest follow-up were significantly lower in patients undergoing stent-assisted coiling than those undergoing simple coiling. Thus, use of the stent-assisted neck remodelling technique in the treatment of wide-necked posterior communicating artery intracranial aneurysms appears to improve the long-term clinical outcome.

O-001 A Novel Metal Artefact Removal Software for C-arm CT; A Novel Imaging Modality to Analyze Aneurysms Treated with Stent Assisted Coil Embolization

PurposeStent assisted coil embolization recently became a common treatment strategy for the wide neck aneurysms. Normal digital subtraction angiography (DSA), however, does not allow visualization of the deployed stents. With...

Endovascular treatment for superior cerebellar artery aneurysms: morphological features, technique, and outcome.

Superior cerebellar artery (SCA) aneurysms have distinctive morphologic configurations and vascular origins. Herein, we have analyzed the angioarchitectural characteristics of SCA aneurysms and outcomes achieved through endovascular treatment. Data accruing prospectively from January, 2002 to September, 2013 yielded 53 SCA aneurysms in 53 patients. Each lesion was classified as either basilar artery (BA), BA-SCA, or SCA type, according to the nature of incorporated vasculature. Clinical and morphologic outcomes were assessed, with emphasis on technical aspects of treatment. Angles formed by SCA and posterior cerebral artery were obtuse (124.8 ± 29.1°) on sides ipsilateral to aneurysms, differing significantly from contralateral counterparts (44.8 ± 22.0°) (p<0.001). The most common type of aneurysm was BA-SCA (54.7 %), followed by SCA (28.3 %) and BA (17.0 %), and BA type aneurysms were the largest in size. Steam-shaped S-configured microcatheters (n=19, 67.9 %) facilitated aneurysm selection for approach via contralateral vertebral artery (n=28), whereas pre-shaped 45/90/J microcatheters (n=21, 84.0 %) primarily were used for ipsilateral vertebral artery approach (n=25). Single-microcatheter technique (52.8 %) was most often applied, followed by double-microcatheter (34.0 %), stent-assisted (9.4 %), and microcatheter-protection techniques (3.8 %). Aneurysmal occlusion was satisfactorily achieved in 45 lesions (82.1 %), with no procedure-related morbidity and mortality. In follow-up monitoring of 46 patients for a mean period of 25.8 ± 24.4 months, only a single instance of major recanalization (2.2 %) occurred. Coil embolization of SCA aneurysms is a safe and effective treatment modality, enabling individualized procedural strategies to accommodate distinctive angio-anatomic configurations.

Treatment of symptomatic fusiform aneurysm in basilar artery by stenting following coiling technique.

The present stent-assisted coil technique has many limitations especially in treating fusiform aneurysms. We aimed to introduce stenting following coiling technique to treat fusiform aneurysms. From January 2009 to December 2010, we treated 6 patients with fusiform aneurysms in basilar artery (BA) by stenting following coiling technique. The 6 patients included four men and two women (age from 20 to 78 years, mean age 51 years). Two patients had subarachnoid hemorrhage, whereas 4 had unruptured aneurysms with progressive brainstem symptoms. In the procedure of endovascular treatment, the stent was delivered after coiling to compress the coils against the aneurysm wall and form a lumen in basilar artery. Five patients had an excellent recovery with a satisfactory clinical result with an average 15.4 months follow-up. Four patients received follow-up angiographic imaging with an average 13 months, whereas 3 patients demonstrated complete aneurysm occlusion with reconstructive BA patency. Re-growth occurred in one patient, although clinically stable. None had angiographic evidence of in-stent stenosis. Stenting following coiling technique may be a feasible and effective method to reshape parent arteries and to embolize fusiform aneurysms safely. However, this technique may be considered in selected patients.

Temporary Solitaire Stent-Assisted Coiling: A Technique for the Treatment of Acutely Ruptured Wide-Neck Intracranial Aneurysms

Wide-neck intracranial aneurysms in patients with acute SAH are often challenging lesions to treat by neurosurgical and endovascular approaches. The aim of this study was to investigate the feasibility, safety, and efficacy of the use of temporary Solitaire AB stent-assisted technique with coiling for the treatment of acutely ruptured wide-neck aneurysms without perioperative antiplatelet therapy. A retrospective review of our endovascular data base identified all patients treated in the acute phase with a temporary stent-assisted technique by use of a fully resheathable Solitaire AB stent and coiling. One-year clinical and angiographic outcomes were evaluated. Eight patients (5 women and 3 men; mean age, 57.5 years) with 8 ruptured wide-neck aneurysms were treated. There were 3 complications without clinical impact. Postoperative complete occlusion was achieved in 5 aneurysms, and 3 had a neck remnant. Three patients had an mRS score of 0, and 1 an mRS score of 3. Among the 4 patients admitted with a World Federation of Neurological Societies grade of V, 1 died, 1 improved to an mRS score of 1, and the other 2 achieved mRS scores of 4 and 5. Five had a stable occlusion, and 2 of the 3 incompletely occluded aneurysms underwent recanalization. In this small series, temporary placement of the Solitaire AB stent during coiling was a feasible and effective treatment for acutely ruptured wide-neck aneurysms. This technique, avoiding the need for perioperative antiplatelet therapy, could be a valuable option for the treatment of such lesions when the balloon remodeling technique is either not an option or unsuccessful.

Various techniques of stent-assisted coil embolization of wide-necked or fusiform artherosclerotic and dissecting unruptured vertebrobasilar artery aneurysms for reducing recanalization: mid-term results

Coil embolization of wide-necked or fusiform vertebrobasilar aneurysms is challenging and tends to involve frequent recanalization. The aim of our study was to evaluate complications and mid-term outcomes of complex vertebrobasilar artery aneurysms after stent-assisted coiling with various techniques. We retrospectively evaluated 28 cases of unruptured vertebrobasilar aneurysm treated by stent-assisted coiling. Forty-four of the 45 stents placed in 28 patients were deployed at the desired location (97.8 %). Single stent-assisted coiling was performed in 14 aneurysms, a stent-within-a-stent (SWS) technique was used in 12 aneurysms, and Y-stent-assisted coiling was employed in four basilar tip aneurysms. Two basilar tip aneurysms treated by single stent-assisted coiling recurred and were retreated by SWS and Y-stent-assisted coiling. Complete embolization was achieved in 19 aneurysms (67.8 %), and remnant neck persisted in eight aneurysms (28.6 %) and remnant aneurysm was noted in one aneurysm (3.6 %). Permanent neurologic deficit (Modified Rankin Scale 1 and 4) was noted in two patients (7.1 %). Angiographic follow-up (mean follow-up period: 20.8 months) was performed in 20 patients. Major recanalization occurred in two basilar tip aneurysms (10 %) and minor compaction was noted in one superior cerebellar artery aneurysm. The remaining 17 aneurysms were stable or improved (85 %). Complex vertebrobasilar aneurysm embolization with stent-assisted techniques was effective and feasible as a method for reducing recanalization during midterm angiographic follow-up. Large and wide-necked basilar tip aneurysms showed frequent major recanalization, and compact packing with single or Y-stent-assisted coiling is needed to prevent recanalization even if coiling will be done without stenting.

Analysis of Complications and Recurrences of Aneurysm Coiling with Special Emphasis on the Stent-Assisted Technique

Stent-assisted coiling has expanded the treatment of intracranial aneurysms. With the use of continuously compiled data, we reviewed the role and drawbacks of stent-assisted coiling. We compiled data from consecutive patients from 2003-2012 who underwent coiling, with or without stent assistance. Clinical and angiographic results were analyzed retrospectively. Of 1815 saccular aneurysms in 1505 patients, 323 (17.8%) were treated with stents (299 procedures) and 1492 (82.2%) without stents (1400 procedures). Procedure-related complications occurred in 9.4% with stents versus 5.6% without stents (P = .016, relative risk 1.5; 95% CI, 1.1-2.7). Ischemic complications were more frequent in the stent group than in the no-stent group (7.0% versus 3.5%; P = .005; relative risk, 1.7; 95% CI 1.2-2.5), as were hemorrhagic complications (2.3% versus 1.9%, P = .64). Procedure-induced mortality occurred in 2.7% (8/299) with stents versus 1.1% (15/1400) without stents (P = .029; relative risk, 2.0; 95% CI, 1.1-3.5). Logistic regression analysis identified wide-neck aneurysms as the most significant independent predictor of complications. A total of 64.1% (207/323) of aneurysms treated with stents and 70.3% (1049/1492) treated without stents have been followed, disclosing angiographic recurrence in 15.5% (32/207) versus 35.5% (372/1049), respectively (P < .0001). Logistic regression analysis showed that the presence of a stent was the most important factor for the reduction of angiographic recurrence (P < .0001; relative risk, 2.3; 95% CI, 1.6-3.3). The stent-assisted coiling technique is associated with a significant decrease in recurrences but a significant increase in complications. The treatment of wide-neck aneurysms remains hazardous.

Endovascular treatment of ruptured tiny, wide-necked posterior communicating artery aneurysms using a modified stent-assisted coiling technique

The endovascular treatment of patients with tiny, wide-necked aneurysms is technically challenging, due to the small volume for microcatheterization and coil stabilization inside the aneurysm sac. We performed a retrospective study to evaluate the feasibility, effectiveness, and safety of stent-assisted embolization for patients with ruptured, tiny, wide-necked posterior communicating artery (PcomA) aneurysms. Between January 2007 and August 2011, 17 tiny, wide-necked PcomA aneurysms that had ruptured were treated at our institution using a modified stent-assisted technique, with delivery of the first coil inside the aneurysm followed by placement of a self-expanding stent via a second microcatheter. All patients were treated successfully using this modified stent-assisted coiling technique. Initial results showed aneurysm occlusion of Raymond Class 1 in 10 patients, Class 2 in four patients, and Class 3 in three patients. The angiographic follow-up results for 13 patients (mean, 12.5months) showed that all aneurysms remained stable or improved, without any in-stent stenosis or recurrence. Of the other four patients, three refused angiography for economic or personal reasons, and one was lost in follow-up. Clinical follow-up of 16 patients for a mean of 23.8months showed no death or rebleeding. These results imply that endovascular treatment of ruptured tiny, wide-necked PcomA aneurysms using our modified stent-assisted coiling technique is safe and feasible. This technique improves the long-term outcomes of these aneurysms by increasing the packing density and diverting the intra-aneurysmal blood flow.

E-051 Combination of Contrast Enhanced Time-Resolved 3D MRA and 3D Neuroimaging Software for the Evaluation of Brain Aneurysms Treated with Coil Embolisation

PurposeTo improve the visualisation of residual neck in the aneurysms treated with coil embolisation utilising the time-resolved contrast enhanced magnetic resonance angiography (4D MRA).Materials and MethodsA total of 11 patients...

Endovascular Treatment of Ruptured Intracranial Aneurysms

Aneurysmal subarachnoid hemorrhage (SAH) is a catastrophic neurologic event. Early triage of patients with SAH should include cardiopulmonary stabilization, neurologic assessment, and imaging. Conventional angiography with 3-dimensional rendering is necessary to accurately assess aneurysm morphology and location, so that treatment can be planned appropriately. Current evidence suggests that coil embolization can be beneficial for aneurysms amenable to endovascular treatment. The use of remodeling techniques has expanded the range of aneurysms treatable by endovascular means. Balloon remodeling can be a powerful technique for treating ruptured aneurysms with unfavorable morphology. However, stent-assisted technique is associated with significantly higher complication rates in ruptured aneurysms and requires dual antiplatelet agents, and should therefore be considered with great caution for ruptured aneurysms. Complications of ruptured aneurysm embolization include aneurysm perforation, which should be addressed with immediate occlusion of the aneurysm, and thromboembolism, which can be managed most effectively with glycoprotein IIb/IIIa inhibitors.

大型未破裂脳動脈瘤に対するコイル瘤内塞栓術

We retrospectively studied the endosaccular coil embolization of 88 patients with 89 large (maximum diameter ≥10 mm) unruptured intracranial aneurysms (UIAs). The mean aneurysm and neck size were 12.7 ±2.9 mm and 5.7±1.8 mm, respectively. Frequent locations were the paraclinoid segment of the internal carotid artery and posterior communicating artery in the anterior circulation and the basilar artery bifurcation in the posterior circulation. Twenty-one aneurysms (23.6%) presented with the clinical symptoms due to the mass effect. All of the procedures were completed. Embolization techniques used were conventional (simple, balloon-assisted, or double-catheter) techniques in 66 aneurysms and the stent-assisted technique in 23 aneurysms. Overall immediate anatomical outcomes showed complete occlusion (CO) in 50.6%, residual neck (RN) in 29.2%, and residual aneurysm (RA) in 20.2%. Overall radiological follow-up results of the 71 aneurysms showed unchanged in 26.8%, improved in 11.3%, minor recurrence in 22.5%, and major recurrence in 39.4%. The final anatomical outcomes of the aneurysms radiologically followed up were CO in 47.9%, RN in 31.0%, and RA in 21.1%. The stent-assisted technique improved the immediate anatomical outcomes and decreased the risk of recurrence in the short term compared with the conventional techniques. Procedure-related complications occurred in 15.9% of the aneurysms. Four aneurysms (4.5%) had ischemic complications, and two aneurysms (2.2%) had hemorrhagic complications. Only four patients had clinical worsening of the mRS of >1 at the latest clinical follow-up. The permanent morbidity and mortality rates were 3.4% and 1.1%, respectively. The mean clinical follow-up period after endovascular therapy was 34.9±2.9 months (13 days–9.54 years). No patients suffered from aneurysmal subarachnoid hemorrhage (SAH) during the clinical follow-up periods. Permanent clinical worsening of the mass effect occurred in three patients with visual symptoms. Two aneurysms showed transient asymptomatic perianeurysmal edema that improved after administration of steroid therapy. Basilar artery dissection and renal artery injury due to the migration of the femoral sheath guidewire occurred once in each case. Twenty-one aneurysms (23.6%) underwent endosaccular coil re-embolization without any complications. No patients underwent surgical clipping or parent artery scarification. The mean duration between the initial treatment and the first re-embolization was 18.2 months (0.5–48.4 months). Endosaccular coil embolization of the large UIAs is effective and safe. But recurrence and aneurysm growth after endosaccular coil embolization are significant concerns, and patients with visual symptoms may be candidates for parent artery occlusion or surgical clipping.

6FrセルリアンカテーテルDD6を用いたtriple coaxial system

【目的】今回我々が新たに開発した6FrセルリアンカテーテルDD6の有用性について報告する．【方法】未破裂前交通動脈瘤に対するコイル塞栓術，および破裂左中大脳動脈瘤のコイル塞栓術において，8Frガイディングカテーテルのintermediate catheterとして6FrセルリアンカテーテルDD6を使用した．【結果】親血管のアクセス困難を解決し，ガイディングカテーテルのサポートを向上させると同時に，balloonあるいはstent assist techniqueを併用したコイル塞栓術が可能であった．【結論】4Frセルリアンカテーテルを用いたtriple coaxial systemではsimple techniqueによる塞栓術のみが可能であるが，新たに開発した6FrセルリアンカテーテルDD6を用いたtriple coaxial systemであればバルーン併用あるいはEnterprise VRD併用によるコイル塞栓術が可能である．

Various Techniques of Stent-Assisted Coil Embolization of Wide-Necked or Fusiform Middle Cerebral Artery Aneurysms : Initial and Mid-Term Results

ObjectiveTo evaluate the feasibility and clinical and angiographic outcomes of stent-assisted embolization for complex middle cerebral artery (MCA) aneurysms.MethodsThe records of 23 consecutive patients with 24 MCA aneurysms, who underwent stent-assisted embolization of the aneurysm, were retrospectively evaluated.ResultsFifteen aneurysms were treated with one stent and 8 were treated using more than two stents (5 a stent-within-a-stent, 1 triple stents, and two Y-stent). Angiographically, complete or near complete occlusion was achieved in 15 aneurysms (65.2%), residual neck in five (21.7%), and residual aneurysm in three (13.1%). Five aneurysms demonstrated thrombosis within the stent during the procedure and hospitalization, and were resolved by intraarterial and intravenous Tirofiban injection. Symptomatic thromboembolic complications were developed in five patients and permanent deficits demonstrated in two patients with modified Rankin Scale 1 and 2, respectively. Treatment-related permanent morbidity and mortality rates were 8.3% and 0% with relatively high complication rate. Angiographic follow-up was available in 17 aneurysms at 6-31 months (mean, 13.2 months) and showed stable or improved in 15 (88.2%) and major and minor recurrence in one, respectively.ConclusionComplex MCA aneurysms could be treated by stent-assisted coiling and showed lower recanalization rate during mid-term follow-up by effective flow diversion due to various stent-assisted techniques. Our results warrant further study with a longer follow-up period in a larger sample.

The effect of Neuroform stent-assisted coil embolization of wide-necked intracranial aneurysms and clinical factors on progressive aneurysm occlusion on angiographic follow-up

Stent-assisted coil embolization is an endovascular treatment for wide-necked intracranial aneurysms, but the durability of this treatment is not well known. The aim of this study is to investigate the effect of the Neuroform stent (Boston Scientific/Target, Fremont, CA, USA) in progressive occlusion of wide-necked intracranial aneurysms, and to assess any correlation between clinical factors and angiographic follow-up results. The records of 52 patients treated with a Neuroform stent were retrieved for analysis of population characteristics, initial and follow-up angiographic results, and clinical outcomes. Initial angiographic results showed complete occlusion in 21 (40.4%), neck remnants in 22 (42.3%), and residual aneurysms in nine (17.3%). Angiographic follow-up was available in 45 of 52 (86.5%) patients: complete occlusion was achieved in 32 (71.1%), neck remnants were present in eight (17.8%) and residual aneurysms in five (11.1%). Of 31 patients with immediate incomplete obliteration, progressive complete occlusion was achieved in 16 of 28 (57.1%) patients. Clinical follow-up showed good outcomes according to the modified Rankin Scale score. A univariate analysis showed that there was no effect of the tested clinical variables of patient age (p=0.823), gender (p=0.419), aneurysm location (p=0.394), size (p=0.625) and rupture status (p=0.721) on aneurysm occlusion at follow-up. We conclude that the Neuroform stent-assisted neck remodelling technique improves progressive occlusion of wide-necked intracranial aneurysms with good clinical outcomes.

Incidence of cerebral ischemic events after discontinuation of clopidogrel in patients with intracranial aneurysms treated with stent-assisted techniques

The optimal antiplatelet medication protocol for prevention of thrombotic complications after stent-assisted coil embolization of cerebral aneurysms is unclear. Early cessation of antiplatelet agents may be associated with an increased risk of cerebral ischemic events. In this study, the authors assess the incidence of stroke or transient ischemic attack (TIA) following discontinuation of a 6-week course of clopidogrel in patients with cerebral aneurysms treated with stent-assisted techniques. A retrospective review was conducted in all patients with cerebral aneurysms undergoing stent-assisted coil embolization or stent-in-stent flow diversion at the University of Iowa during a 24-month period. The antiplatelet protocol was 81 mg aspirin and 75 mg clopidogrel daily for 6 weeks, followed by 325 mg aspirin daily indefinitely. The incidence of stroke or TIA was determined by a retrospective review of medical records generated during a 3-month period following discontinuation of clopidogrel. A total of 154 patients underwent aneurysm treatment with stent techniques during this interval. Documentation of neurological follow-up 3 months after discontinuation of a 6-week clopidogrel treatment was available in 121 (78.6%) of 154 patients. Of these 121 patients, 114 were treated with stent-assisted coil embolization and 7 with stent-in-stent flow diversion. Six patients (5%) suffered an ischemic event after cessation of clopidogrel, with 2 events occurring within the first 2 weeks. Specifically, the rate of ischemic events was 5 (4.3%) of 114 in the "stent-coil" treatment group and 1 (14.3%) of 7 in the stent-in-stent group. Treatment had been performed in the setting of a subarachnoid hemorrhage in 1 patient. Atypical aneurysm features and technical factors predisposing to thrombotic events were found in all but one of these patients. Similarly, cardiovascular risk factors were present in 5 of the 6 patients in whom ischemic events developed after clopidogrel discontinuation. Clopidogrel discontinuation is associated with a 5% risk of ischemic events in patients treated with stent techniques. Any stroke related to clopidogrel discontinuation is avoidable, and longer treatment is therefore clearly necessary. Patients with cardiovascular risk factors, high-risk aneurysm features, and those undergoing stent-in-stent flow diversion might benefit the most from longer clopidogrel therapy.

Tiny aneurysms treated with single coil: Morphological comparison between bare platinum coil and matrix coil

ObjectiveWe analyzed the angiographic results of tiny aneurysms treated with various kinds of single coils including polyglycolic-polylactic acid (PGLA)-coated coils. MethodsForty aneurysms with diameters measuring less than 4mm were treated with a single bare platinum, Matrix1, or Matrix2 coil. Most of the aneurysms were treated with a 2mm diameter coil, except for seven treated with a 3mm coil, four treated with a 2.5mm coil, and two treated with a 1.5mm coil. The mean length of the coils was 3.6cm. ResultsWith mean packing ratios of 21.2%, 19.7%, and 22.8%, we achieved initial complete occlusion rates of 9.5% with the platinum coil, 28.6% with the Matrix1 coil, and 25.0% with the Matrix2 coil. The mean follow-up interval was 23.1 months and the complete occlusion rate improved up to 47.6% for the platinum coil, 57.1% for the Matrix1 coil, and 83.3%for the Matrix2 coil. Compared to the Platinum group, the Matrix2 group showed a greater tendency toward more complete occlusion on the follow-up images. Regardless of coil type, the aneurysms treated with a stent-assisted technique showed better complete occlusion rates (50.0% vs. 90.0%, p=0.03). ConclusionsThe tiny aneurysms treated with a single Matrix2 coil tended to have better follow-up angiographic results than the aneurysms treated with a single platinum coil. Furthermore, the use of a stent-assisted technique and increasing the packing density also positively affected the healing of these tiny aneurysms.

Abstract 3464: Incidence of Cerebral Ischemia After Discontinuation Of Clopidogrel (Plavix) In Patients With Cerebral Aneurysms Treated Using Stent-Assisted Technique

Background: The optimal antiplatelet medication protocol for prevention of thrombotic complications after stent-assisted coil embolization of cerebral aneurysms is unknown. Premature cessation of antiplatelet medication has been associated with increased risk of thrombosis. The current analysis is undertaken to assess the incidence of stroke or transient ischemic attack after discontinuation of 6 weeks of prescribed clopidogrel (Plavix) in patients with cerebral aneurysms treated by stent-assisted technique. Method: 275 patients with cerebral aneurysms treated at the University of Iowa Hospitals and Clinics by a single surgeon (DH) during a period of 24 months were retrospectively analyzed for aneurysms treated by stent-assisted coiling or stent-in-stent flow diversion and who also received follow-up at our center. Our antiplatelet protocol was aspirin 81 mg PO and plavix 75 mg PO daily for 6 weeks, followed by aspirin 325 mg PO daily indefinitely. Patients were assessed for incidence of stroke or transient ischemic attack as diagnosed by a neurologist or neurosurgeon by reviewing their medical record during the period of three months following discontinuation of plavix. Results: 154/275 (56%) patients underwent stent-assisted coil embolization during this interval. Documentation of neurologic follow-up after discontinuation of six-weeks of palvix treatment was available in 121/154 (78.6%) patients. Seven patients suffered an ischemic event after cessation of plavix (5.7%) with stroke in 6 patients (5.0%) and transient ischemic attack in 1 patient (0.8%). These events developed over a wide range of intervals from time of plavix discontinuation (1-12 weeks), with only one event within 2 weeks. Conclusion: The three-month incidence of cerebral ischemic events in patients treated with stent-assisted technique is low following cessation of six-week treatment of plavix. Events within two weeks of discontinuation were rare, suggesting etiologies other than stent thrombosis may have been operative in our patients.