Endovascular treatment of wide-neck middle cerebral artery aneurysms with stents: a review of 16 cases

Clipping versus coiling for treatment of middle cerebral artery aneurysms: a retrospective Italian multicenter experience

Endovascular treatment has emerged as the predominant approach in intracranial aneurysms. However, surgical clipping is still considered the best treatment for middle cerebral artery (MCA) aneurysms in referral centers. Here we compared short- and long-term clinical and neuroradiological outcomes in patients with MCA aneurysms undergoing clipping or coiling in 5 Italian referral centers for cerebrovascular surgery. We retrospectively reviewed 411 consecutive patients admitted between 2015 and 2019 for ruptured and unruptured MCA aneurysm. Univariate and multivariate analyses of the association between demographic, clinical, and radiological parameters and ruptured status, type of surgical treatment, and clinical outcome at discharge and follow-up were performed. Clipping was performed in 340 (83%) cases, coiling in 71 (17%). Clipping was preferred in unruptured aneurysms and in those showing collateral branches originating from neck/dome. Surgery achieved a higher rate of complete occlusion at discharge and follow-up. Clipping and coiling showed no difference in clinical outcome in both ruptured and unruptured cases. In ruptured aneurysms age, presenting clinical status, intracerebral hematoma at onset, and treatment-related complications were significantly associated with outcome at both short- and long-term follow-up. The presence of collaterals/perforators originating from dome/neck of the aneurysms also worsened the short-term clinical outcome. In unruptured cases, only treatment-related complications such as ischemia and hydrocephalus were associated with poor outcome. Clipping still seems superior to coiling in providing better short- and long-term occlusion rates in MCA aneurysms, and at the same time, it appears as safe as coiling in terms of clinical outcome.

Endovascular treatment of small (< 5 mm) unruptured middle cerebral artery aneurysms

Purpose

We report our experience with endovascular treatment of these lesions, with special consideration of angiographic and clinical outcomes and periprocedural complications.

Material and methods

The analysis included treatment results of 19 patients with 20 aneurysms. The aneurysm size ranged from 1.9 to 4.7 mm (mean 3.8, SD 0.7). Clinical examinations with the use of modified Rankin Score and angiographic outcomes were evaluated initially postembolisation and at a minimum follow-up of six months.

Results

Initial post-treatment complete and near-complete aneurysm occlusion was achieved in 19 (95%) cases and incomplete occlusion in one (5%) case. Imaging follow-up, performed in 17 (89.4%) patients, showed no change in the degree of occlusion in 16 (94.1%) patients and coil compaction in one (5.9%). There were no retreatment procedures. The procedure-related mortality rate was 5% (1/20) and was associated with intraprocedural aneurysm rupture. There was a case of a clinically silent coil prolapse into the parent artery. The clinical follow-up evaluation achieved in 17 (89.4%) patients showed no change in clinical status in all followed patients.

Conclusions

Endovascular treatment of small unruptured middle cerebral artery aneurysms is feasible and effective. The procedure-related complications are not negligible, especially in terms of the benign natural course of these lesions.

Endovascular coiling of proximal middle cerebral artery aneurysms: is it safe and durable?

BACKGROUND

Proximal middle cerebral artery (M1 segment) aneurysms are relatively deeply located in neighboring lenticulostriate arteries, which make them unsuitable for microsurgery. We aimed to investigate the clinical and radiological outcomes of endovascular coiling of M1 segment aneurysms.

METHODS

Between January 2003 and December 2014, we retrospectively reviewed the medical records of 52 patients (52 aneurysms) from four institutions who underwent endovascular coiling of M1 segment aneurysms. Patients who underwent clinical and radiologic follow-up for more than a year after the procedure were evaluated.

RESULTS

The aneurysms were located in the early frontal branch, early temporal branch, and lenticulostriate artery in 28, 15, and nine patients, respectively. Endovascular coiling was achieved in 51 cases and failed in one case. Of these 51 cases, 46 (90.2%) and five (9.8%) were non-ruptured and ruptured aneurysms, respectively. Initial angiographic results revealed complete occlusion in 26 (51.0%), residual neck in 16 (31.4%), and residual sac in nine (17.6%) cases. One failed case had a symptomatic procedural complication of thromboembolism. However, there was no permanent morbidity or mortality. Two major recanalization cases (3.9%) were retreated by endovascular coiling. On multivariable logistic regression analysis, aneurysmal recurrence was significantly related to aneurysm height (OR, 1.887; 95% CI, 1.107 to 3.217; p = 0.020), width (OR, 1.836; CI, 1.127 to 2.992; p = 0.015), and neck (OR, 4.017; CI, 1.220 to 13.232, p = 0.022).

CONCLUSION

Endovascular coiling of M1 segment aneurysms appeared to be a feasible treatment option with a relatively low-retreatment rate. Aneurysm size was statistically significantly associated with recurrence.

Treatment of Intracranial Aneurysms with Self-Expandable Braided Stents: A Systematic Review and Meta-Analysis

BACKGROUND

The safety and efficacy of treatment with self-expandable braided stents (LEO and LVIS) required further investigation.

PURPOSE

Our aim was to analyze the outcomes after treatment with braided stents.

DATA SOURCES

A systematic search of 3 databases was performed for studies published from 2006 to 2017.

STUDY SELECTION

According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we included studies reporting patients treated with LEO or LVIS stents.

DATA ANALYSIS

Random-effects meta-analysis was used to pool the following: aneurysm occlusion rate, complications, and neurologic outcomes.

DATA SYNTHESIS

Thirty-five studies evaluating 1426 patients treated with braided stents were included in this meta-analysis. Successful stent delivery and complete aneurysm occlusion were 97% (1041/1095; 95% CI, 95%-98%) (I² = 44%) and 88.3% (1097/1256; 95% CI, 85%-91%) (I² = 72%), respectively. Overall, treatment-related complications were 7.4% (107/1317; 95% CI, 5%-9%) (I² = 44%). Ischemic/thromboembolic events (48/1324 = 2.4%; 95% CI, 1.5%-3.4%) (I² = 27%) and in-stent thrombosis (35/1324 = 1.5%; 95% CI, 0.6%-1.7%) (I² = 0%) were the most common complications. Treatment-related morbidity was 1.5% (30/1324; 95% CI, 0.9%-2%) and was comparable between the LEO and LVIS groups. Complication rates between the anterior (29/322 = 8.8%; 95% CI, 3.4%-12%) (I² = 41%) versus posterior circulation (10/84 = 10.5%; 95% CI, 4%-16%) (I² = 0%) and distal (30/303 = 8%; 95% CI, 4.5%-12%) (I² = 48%) versus proximal aneurysms (14/153 = 9%; 95% CI, 3%-13%) (I² = 46%) were comparable (P > .05).

LIMITATIONS

Limitations were selection and publication biases.

CONCLUSIONS

In this analysis, treatment with the LEO and LVIS stents was relatively safe and effective. The most common complications were periprocedural thromboembolisms and in-stent thrombosis. The rate of complications was comparable among anterior and posterior circulation aneurysms, as well as for proximal and distally located lesions.

Long term follow-up of bifurcation aneurysms treated with braided stent assisted coiling and complex T- and Y- stent constructs

Background

Stent assisted coil embolization (SACE) of bifurcation aneurysms is challenging. Heterogeneous results have been achieved to date, but largely for laser cut stents. While braided stents offer multiple technical advantages, their long term efficacy has yet to be validated.

Objective

To report the first long term 18 month results for the durability of bifurcation aneurysms treated with braided stents.

Materials and methods

Over a 4 year period, 59 consecutive patients with 60 bifurcation aneurysms underwent elective braided SACE across three Australian neurovascular centers. 17 of these aneurysms underwent T- or Y-shaped stent constructs. All patients had immediate, 6 month and 18 month clinical and radiological follow-up. Radiological assessment was made on modified Raymond–Roy occlusion scores while clinical assessment was based on the modified Rankin Scale. Subgroup analysis of 17 aneurysms treated with multi-stent constructs was conducted.

Results

6 month follow-up data were available for 59 aneurysms and 18 month follow-up data for 58 aneurysms. Satisfactory aneurysm occlusion was achieved in 97% at inception and at 6 months, and 98% at 18 months. Good neurological outcomes were achieved in 95% at 18 months. Similar satisfactory results were achieved with the multi-stent construct cohort. Intraprocedural thromboembolic events were recorded in 5% and delayed events in 2%. Technical complications were found in 5%. All complication rate was 13%.

Conclusion

Braided SACE was safe, efficacious, and durable at the long term 18 month follow-up, including for multi-stent constructs. Preliminary results indicate favorable clinical and radiological outcomes compared with laser cut stents.

Aneurysmal Neck Clipping as the Primary Treatment Option for Both Ruptured and Unruptured Middle Cerebral Artery Aneurysms

Objective

Although middle cerebral artery (MCA) aneurysms are less amenable to coil embolization, an increasing number of studies support favorable endovascular treatment for them. The purpose of this study is to compare the outcomes of two different treatments (surgery versus coiling) and evaluate the benefits of surgical clipping for MCA aneurysms.

Methods

Here we retrospectively analyzed the outcomes of 178 ruptured and unruptured MCA aneurysms treated in patients between September 2008 and April 2012. Parameters assessing treatment outcomes include degree of aneurysm occlusion, presence of regrowth, clinical status, and complications.

Results

Among 178 MCA aneurysms, 153 were treated surgically. After a mean follow-up of 12 months, the surgery group showed a clinically significant complete occlusion rate (98%) compared with the coiling group (56%) (p<0.001). Follow-up radiologic evaluation showed a higher regrowth rate (four of 16 cases) in the coiling group than in the surgery group (one of 49 cases) (p=0.003). There was no statistically significant difference in favorable clinical outcome rate between the two groups. The procedure-related permanent morbidity and mortality rates were 2% (three of 153 cases) in the surgery group and 0% (0 of 25 cases) in the coiling group.

Conclusion

Compared to endovascular treatment, surgical neck clipping for both ruptured and unruptured MCA aneurysms results in a significantly higher complete obliteration rate and less regrowth. Therefore, even in this endovascular era, we still recommend surgical clipping as the primary treatment option for MCA aneurysms rather than coil embolization.

"Clip first" policy in management of intracranial MCA aneurysms: Single-centre experience with a systematic review of literature

BACKGROUND

The results of microsurgical treatment for middle cerebral artery (MCA) aneurysms (ANs) have been highly satisfying for decades, notoriously posing a challenge for interventional neuroradiologists. Following the International Subarachnoid Aneurysm Trial (ISAT) study results, most centres across Europe and the USA switched to a "coil first" policy. The purpose of this study is to evaluate and critically review the substantiation of this change.

METHODS

The authors conducted a single-institution retrospective study of MCA AN treatment between January 2000 and December 2013 maintaining a "clip first" policy. The results are supplied with a literature review.

RESULTS

A total of 315 MCA ANs were treated in 288 consecutive patients (209 females, 79 males). Microsurgical treatment was performed for 238 AN patients (116 ruptured, 122 unruptured) and 77 AN patients (46 ruptured, 31 unruptured) who underwent a coiling procedure. Treatment-related morbidity and mortality (MM) for unruptured ANs was 2.8 % in the microsurgical group and 10.3 % in the endovascular group. The percentage of patients with no/minor permanent neurological deficits after SAH in a good initial clinical state (HH 1-2) was 93 % in the microsurgical and 76 % in the endovascular group. A literature review identified 21 studies concerning MCA AN treatment with a specified decision-making algorithm. Microsurgery seemed superior to endovascular management regarding both clinical and radiological outcomes, although several aspects of the analysed reports might appear questionable.

CONCLUSION

Although this study has its inherent limitations, the effect brought about by microsurgical clipping of MCA ANs remains superior to that of endovascular embolisation and it should be sustained as the first treatment choice. The decision about the treatment strategy should be made by a multi-disciplinary team consisting of specialists from both teams, bearing in mind the higher occlusion rate and longevity of the surgical treatment.

Complications in Stent-Assisted Endovascular Therapy of Ruptured Intracranial Aneurysms and Relevance to Antiplatelet Administration: A Systematic Review

BACKGROUND AND PURPOSE

Despite the increasing use of stent-assisted coiling for ruptured intracranial aneurysms, there is little consensus regarding the appropriate antiplatelet administration for this. The objectives of this systematic review were to provide an overview of complications and their association with the method of antiplatelet administration in stent-assisted coiling for ruptured intracranial aneurysms.

MATERIALS AND METHODS

A comprehensive search of the literature in the data bases was conducted to identify studies reporting complications of stent-assisted coiling for ruptured intracranial aneurysms. The pooled event rate of preprocedural thromboembolisms, hemorrhages, and mortality was estimated from the selected studies. Subgroup analyses were performed by the method of antiplatelet administration (pre-, postprocedural, and modified). Meta-analysis was conducted to compare periprocedural complications and mortality between ruptured intracranial aneurysms and unruptured intracranial aneurysms.

RESULTS

Of the 8476 studies identified, 33 with 1090 patients were included. The event rates of thromboembolism and intra- and postprocedural hemorrhage were 11.2% (95% CI, 9.2%-13.6%), 5.4% (95% CI, 4.1%-7.2%), and 3.6% (95% CI, 2.6%-5.1%), respectively. Subgroup analyses of thromboembolism showed a statistically significant difference between groups (P < .05). In the preprocedural and modified antiplatelet groups, the risk for thromboembolism in stent-assisted coiling for ruptured intracranial aneurysm was not significantly different from that for unruptured intracranial aneurysm, though this risk of the postprocedural antiplatelet group was significantly higher in ruptured intracranial aneurysms than in unruptured intracranial aneurysms.

CONCLUSIONS

On the basis of current evidence, complications of stent-assisted coiling for ruptured intracranial aneurysm may be affected by the method of antiplatelet administration.

Kissing-Y stenting for endovascular treatment of complex wide necked bifurcation aneurysms using Acandis Acclino stents: results and literature review

Introduction

Y-configured stent assisted coiling is a promising therapeutic option to ensure safe coil embolization and preserve the affected arteries in complex wide necked aneurysms. We present our experience with self-expanding Acandis Acclino stents for the treatment of complex aneurysms using the kissing-Y technique.

Methods

We retrospectively reviewed seven patients with seven complex aneurysms (three anterior communicating artery (AcomA), two middle cerebral artery, one basilar artery/superior cerebellar artery, and one vertebral artery/posterior inferior cerebellar artery) who were treated with the kissing-Y technique by stent assisted coiling from June 2013 to July 2014, with follow-up until January 2015. DSA follow-up was up to 17 months, with a mean follow-up period of 10 months. Six patients were treated electively and one in the acute phase of a subarachnoid hemorrhage. In all cases, closed cell Acandis Acclino stents were used. We evaluated procedural complications, clinical outcomes, and mid term angiographic follow-up. Additionally, a literature review is provided.

Results

In all patients, stents were successfully placed and implanted. One patient developed a periprocedural thromboembolic complication not directly related to the stents. No other periprocedural or postprocedural complications were encountered. Follow-up examinations showed stable and total occlusion of all coiled aneurysms.

Conclusions

The results of our study show that the kissing-Y technique using closed cell Acandis Acclino stents followed by coil embolization is a feasible treatment option for selected complex bifurcation aneurysms.

Endovascular Treatment of Middle Cerebral Artery Aneurysm with the LVIS Junior Stent

BACKGROUND

Middle cerebral artery (MCA) aneurysms often occur in small parent vessels and are incorporated with the orifice of acute-angled efferent branch vessels. Endovascular treatment for these aneurysms remains technically challenging. This study aimed to assess the clinical safety and efficacy of the Low-profile Visualized Intraluminal Support Junior (LVIS Jr) stent for embolization of MCA aneurysms.

METHODS

Eighteen intracranial aneurysms, including 13 unruptured and 5 ruptured aneurysms, were treated with LVIS Jr stent-assisted coil embolization. The clinical data and technical results are presented.

RESULTS

A total of 18 stents were successfully delivered to the target aneurysms, and the technical success rate was 100%. There was complete occlusion in 8 (44.4%) of 18 cases, neck remnants in 7 (38.9%) cases, and partial occlusion in 3 (16.7%) cases. In-stent thrombosis occurred in 1 case, and the symptoms disappeared after transvenous tirofiban injection. The modified Rankin Scale score at discharge was 0 in 14 patients, 1 in 3 patients, and 2 in 1 patient.

CONCLUSIONS

The LVIS Jr stent provided excellent trackability and deliverability and is safe and effective for the treatment of wide-necked MCA aneurysms with tortuous and smaller parent vessels.

Enterprise stent-assisted coiling for wide-necked intracranial aneurysms during ultra-early (48hours) subarachnoid hemorrhage: a single-center experience in 59 consecutive patients

BACKGROUND AND OBJECTIVE

Accumulated experience and improvement of stents dedicated to intracranial use have significantly widened the applicability of stent-assisted coiling (SAC) to ruptured wide-necked aneurysms. This retrospective study was designed to evaluate the safety and efficacy of SAC using the Enterprise stent for ruptured wide-necked intracranial aneurysms during ultra-early subarachnoid hemorrhage.

METHOD

We reviewed data from 59 consecutive patients with ruptured wide-necked aneurysms who had SAC using the Enterprise stent performed within 48hours of onset. Data collected and analyzed included: patient demographics; morphologic features of the aneurysm; treatment results and follow-up results. Clinical outcomes were evaluated by modified Rankin Scale (mRS).

RESULTS

In all 59 cases, SAC using the Enterprise stent was performed successfully, with no significant technical difficulties. Initial angiographic results were: complete occlusion in 38 cases; near occlusion in 17; and partial occlusion in four. Angiographic follow-up of 48 patients showed that 46 (95.8%) remained stable or improved, without regrowth, while regrowth was imaged in two patients. Medium-term clinical follow-up of 54 patients (mean, 26.9months) showed that 88.9% had a good outcome (mRS: 0 in 34; 1 in eight; and 2 in six), and 11.1% poor outcomes (mRS: 3 in four; and 4 in two).

CONCLUSION

Enterprise SAC is a safe and viable option for treatment of ruptured wide-necked aneurysms within 48hours of ictus.

"Y" and "X" stent-assisted coiling of complex and wide-neck intracranial bifurcation aneurysms

BACKGROUND AND PURPOSE

Stent-assisted coiling with two stents has been described in some series for the treatment of complex and wide-neck bifurcation aneurysms. Our aim was to report our experience of a stent-assisted coiling technique with double stents in "Y" and "X" configurations, with emphasis on safety, feasibility, and efficacy.

MATERIALS AND METHODS

Clinical and angiographic outcomes of patients for whom the strategic therapeutic option was the stent-assisted coiling technique in a Y or X configuration for neck scaffolding from June 2006 to June 2013 were retrospectively analyzed.

RESULTS

One hundred five aneurysms in 97 patients were treated during 100 consecutive procedures. There were 54.2% (57/105) MCA, 28.6% (30/105) anterior communicating artery, 16.2% (17/105) basilar tip, and 1.0% (1/105) ICA termination aneurysms. A Y stent placement was used to treat 87 aneurysms in 85 procedures; an X stent placement was used to treat 7 aneurysms in 6 procedures, while 9 procedures failed for 11 aneurysms. There were 10.0% (10/100) procedure-related permanent neurologic deficits and 1.0% (1/100) death. The immediate angiographic controls showed a complete occlusion in 47.6% (50/105) of the aneurysms and a partial (neck or sac remnant) occlusion in 52.4% (55/105). To date, 81.0% (85/105) of the aneurysms have been followed up (mean, 17 months) with angiography, disclosing a recanalization in 5.9% (5/85) and an improvement in 42.4% (36/85). At discharge and follow-up, the mRS score was 0 in 83.5% (81/97) of patients, 1 in 4.1% (4/97), 2 in 3.1% (3/97), 3 in 4.1% (4/97), 4 in 3.1% (3/97), and 6 in 2.1% (2/97).

CONCLUSIONS

Y and X stent-assisted coiling of complex and wide-neck intracranial bifurcation aneurysms is an effective technique.

Stent placement for complex middle cerebral artery aneurysms

BACKGROUND

To evaluate the safety and effectiveness of stent placement for ruptured or unruptured middle cerebral artery (MCA) aneurysms in a larger number.

METHODS

Between October 2003 and December 2012, data for 70 patients with 72 complex MCA aneurysms treated with stents at our institution were retrospectively collected and analyzed.

RESULTS

Eighty-five stents were successfully deployed in this series. However, failure of followed coiling was encountered in 2 (2.8%) tiny aneurysms of them. Of the 63 aneurysms treated with stent-assisted coiling, complete occlusion was achieved in 22 (34.9%), neck remnant in 15 (23.8%), and residual sac in 26 (36.5%). Of the 9 aneurysms treated with stent alone, the results were contrast stasis in 3 aneurysms and no change in 6. Procedure-related complications occurred in 9 (12.5%) procedures, including 7 of 27 (25.9%) with ruptured aneurysms and 2 of 45 (4.4%) with unruptured aneurysms, which resulted in 1 death and 5 disabilities. Univariate and multivariate analyses show that ruptured aneurysm is an independent factor for the outcome of these patients (odds ratio, 7.35; 95% confidence interval, 1.35-40.0). Angiographic follow-up results (mean, 10.5±8.8 months) showed that 72.1% (44 of 61) were completely occluded, 4.9% (3 of 61) recurred, and others were stable or had improved. Intrastent stenosis was observed in 1 (1.6%) patient, which was managed conservatively. During a clinical follow-up period ranging from 7 to 113 months (mean, 33.0±22.4 months), 1 disabled patient died from severe pneumonia, whereas the clinical status of the others had improved or was stable. Procedure-related morbidity/mortality during the follow-up for the ruptured and unruptured groups were 3.7%/3.7% and 0/0, respectively.

CONCLUSIONS

Our study shows that stent placement for the treatment of certain wide-neck MCA aneurysms is feasible, safe, and effective. However, stent placement for acutely ruptured MCA aneurysms harbors a much higher complication rate.

Endovascular and Surgical Treatment of Unruptured MCA Aneurysms: Meta-Analysis and Review of the Literature

Introduction. The best treatment for unruptured middle cerebral artery (MCA) aneurysms is unclear. We perform a meta-analysis of recent publications to evaluate the results of unruptured MCA aneurysms treated with surgical clipping and endovascular coiling. Methods. A PubMed search for articles published between January 2004 and November 2013 was performed. The R statistical software package was used to create a random effects model for each desired incidence rate. Cochran's Q test was used to evaluate possible heterogeneity among the rates observed in each study. Results. A total of 1891 unruptured MCA aneurysms, 1052 clipped and 839 coiled, were included for analysis. The complete occlusion rate at 6–9 months mean follow-up was 95.5% in the clipped group and 67.8% in the coiled group (P < 0.05). The periprocedural thromboembolism rate in the clipping group was 1.8% compared with 10.7% in the aneurysms treated by coiling (P < 0.05). The recanalization rate was 0% for clipping and 14.3% for coiling (P = 0.05). Modified Rankin scores of 0–2 were obtained in 98.9% of clipped patients compared to 95.5% of coiled (NS). Conclusions. This review weakly supports clipping as the preferred treatment of unruptured MCA aneurysms. Clinical outcomes did not differ significantly between the two groups.

Evolving role of endovascular treatment for MCA bifurcation aneurysms: case series of 184 aneurysms and review of the literature

OBJECTIVE

This study evaluates the role of endovascular therapy for middle cerebral artery (MCA) aneurysms and its evolution over time. We are reporting a large case series of 184 MCA aneurysms and comparative analysis of the literature.

METHODS

This was a retrospective review of a prospectively maintained database including all patients with MCA bifurcation aneurysms embolized between 2000 and 2013. There were 184 aneurysms in 166 patients, with 71 ruptured and 113 nonruptured aneurysms.

RESULTS

Stent assistance was required in 70 cases (38·0%) and 3 cases (1·6%) required 'Y' stenting. The initial rate of total aneurysm occlusion was 59·8% and at delayed follow up was 90·1%. Seven embolizations resulted in thrombo-embolic complications (3·8%), with no cases of aneurysm re-bleeding, wire perforations, or other hemorrhages. Three patients with ruptured aneurysms died of causes unrelated to the embolization, and none with nonruptured aneurysms died in the follow-up period (total mortality 1·6% at 30 days post-procedure). A total of seven aneurysms (3·9%) required retreatment with an average follow up of 41 months. Prior to dedicated aneurysm stents, 68·8% of patients underwent embolization with the remainder surgically treated. Following the introduction of aneurysm stents in 2002, 92·0% of MCA aneurysms treated were embolized.

CONCLUSIONS

During the past decade we have seen a treatment paradigm shift in MCA aneurysm treatment from surgical treatment to endovascular treatment. Developments in 3D angiography, more compliant balloons, dedicated aneurysm stents, complex coils, and antiplatelet therapy regimes have led to this transition for safe and effective management of these patients.

Various techniques of stent-assisted coil embolization of wide-necked or fusiform middle cerebral artery aneurysms : initial and mid-term results

Objective

To evaluate the feasibility and clinical and angiographic outcomes of stent-assisted embolization for complex middle cerebral artery (MCA) aneurysms.

Methods

The records of 23 consecutive patients with 24 MCA aneurysms, who underwent stent-assisted embolization of the aneurysm, were retrospectively evaluated.

Results

Fifteen 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.

Conclusion

Complex 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.

[Interventional angioradiology as a solution for microsurgical flap failure]

The microsurgical failure rate is almost constant for several decades. We present two case reports describing a novel method of free flap salvage using angioradiological techniques. Our first case shows the potential utility of in situ thrombolysis, our second case describes the first use of stents within a microsurgical anastomosis. In boths cases, the flap would have been lost immediately, because flap revisions failed. Thus, before abandoning on a flap, one could perform a simple angiography to evaluate further angioradiological salvage possibilities and hereby contribute to improve long term microsurgical failure rate.

Use of stent-assisted coil embolization for the treatment of wide-necked aneurysms: A systematic review

Background:

The use of stent-assisted coiling (SAC) has been shown to be a treatment option for complex aneurysms. We reviewed systematically the immediate and mid-term angiographic results following treatment of wide-necked aneurysms with self-expanding stents and coils, as well as the peri- and postprocedural rate of complications.

Methods:

A computerized database search was conducted from 01/2000 to 04/2011 using appropriate indexed terms on Pubmed. Inclusion criteria were: (1) homogeneous populations of ≥10 patients with wide-necked aneurysms; (2) use of a self-expandable neurovascular stent and coils for aneurysm treatment; (3) immediate and follow-up angiographic results; and (4) periprocedural and delayed thrombotic complications.

Results:

Seventeen studies were included, containing retrospectively collected data on 656 patients/702 aneurysms. The target aneurysm was located on the anterior circulation in 78.4% of patients. The immediate rate of complete occlusion was 46.3%, (19.3-98.1%). The intra- and postprocedural rate of intrastent thrombosis or thromboembolic event was 4.6% and 4.3%, respectively. Complete occlusion was documented in 71.9% at last angiographic follow-up. The rate of recanalization was 13.2% of aneurysms (0-28.8%). Delayed in-stent stenosis occurred in 5.3% cases (0-20.6%).

Conclusion:

SAC has been considered a treatment option for selected wide-necked aneurysms in some institutions. The use of intracranial stents should take into consideration the risk of ischemic complications, recanalization, delayed in-stent stenosis; and the currently unknown lifetime risks for stenosis, vascular injury, device failure, and aneurysm recurrence related to intracranial stenting. There is an evident need for a prospective multicenter registry for all treated patients with SAC.

Morphology of Middle Cerebral Artery Aneurysms: Impact on Surgical Strategy and on Postoperative Outcome

The outcome of middle cerebral artery (MCA) aneurysm clipping depends on the presence of subarachnoid hemorrhage (SAH). Moreover, it is influenced by anatomical features of the aneurysm and its parent artery. We hypothesized that morphological characteristics of the aneurysm may be predictive for postoperative outcome. Therefore, we identified radiographic assessable details that predicted the surgical difficulty and the risk for new ischemia. The angiograms of 151 consecutive patients (82 presenting with SAH) were analyzed in a standardized fashion focusing on 12 defined morphological aspects. The results were correlated to intraoperative rupture and to postoperative ischemia. Aneurysms presenting with SAH were associated with irregular shape, larger maximum diameter, and larger dome-to-base distance (DBD) and were located more frequently on the M2 segment. Multivariate analysis revealed 6 independent predictors for intraoperative rupture: SAH, location on M2 segment, DBD, maximum diameter, diameter of the parent MCA, and the presence of branching vessel. Independent predictors of surgery-related ischemia were identified: SAH, irregular shape, location on M2 segment, DBD, and the neck-to-vessel ratio (NVR). In MCA aneurysms, independent predictors for the risk of rupture intraoperatively and for the postsurgical outcome were the presence of SAH, location on the M2-segment, size (DBD), and the broadness of the neck.

Incomplete stent apposition in Enterprise stent-mediated coiling of aneurysms: persistence over time and risk of delayed ischemic events

OBJECT

Incomplete stent apposition of the closed cell-design Enterprise stent following stent-mediated coil embolization of intracranial aneurysms has been associated with increased risk of periprocedural thromboembolic events. In this study, the authors seek to determine the natural history of incomplete stent apposition and evaluate the clinical implications of the phenomenon.

METHODS

Since January 2009, all patients receiving Enterprise stents in the treatment of intracranial aneurysms at the authors' institution have undergone serial 3-T MRI with incomplete stent apposition identified by the crescent sign on multiplanar reconstructions of MR angiograms. Magnetic resonance images and MR angiograms obtained at 3, 9, and 18 months after stent-assisted coil embolization were analyzed along with admission and follow-up clinical medical records. These records were evaluated for any radiographic and clinical, transient or permanent ischemic neurological events.

RESULTS

Fifty patients receiving Enterprise stents were eligible for inclusion and analysis in the study. Incomplete stent apposition was identified in postoperative imaging studies in 22 (44%) of 50 patients, with 19 (86%) of 22 crescent signs persisting and 3 (14%) of 22 crescent signs resolving on subsequent serial imaging. Delayed ischemic events occurred in 8 (16%) of 50 cases, and all cases involved patients with incomplete stent apposition. The events were transient ischemic attacks (TIAs) in 5 cases, asymptomatic radiographic strokes in 2 cases, and symptomatic strokes and TIAs in the final case. There were no delayed ischemic events in patients who did not have incomplete stent apposition. Only 1 of the delayed ischemic events (2%) was permanent and symptomatic. The postoperative presence of a crescent sign and persistence of the crescent sign were both significantly associated with delayed ischemic events (p < 0.001 and p = 0.002, respectively).

CONCLUSIONS

Incomplete stent apposition is a temporally persistent phenomenon, which resolves spontaneously in only a small minority of cases and appears to be a risk factor for delayed ischemic events. Although further follow-up is needed, these results suggest that longer duration of antiplatelet therapy and clinical follow-up may be warranted in cases of recognized incomplete stent apposition.

Stent-assisted embolization of 100 middle cerebral artery aneurysms

OBJECT

The introduction of intracranial stents to aneurysm treatment allows endovascular repair of nearly all aneurysms, but the safety and durability of stent-assisted embolization of middle cerebral artery (MCA) aneurysms is unclear.

METHODS

Ninety-one patients with 100 complex MCA aneurysms not amenable to simple coiling were treated with stent-assisted embolization as a first option. Technical and clinical results, initial follow-up imaging, and long-term annual MR angiography (MRA) were reviewed.

RESULTS

Intracranial stents were successfully deployed in all 100 aneurysms. There was 1 case of significant neurological morbidity (1%) and 1 case of death (1%) related to treatment. Initial posttreatment angiography revealed complete occlusion of 48 aneurysms (48%), a residual neck in 21 (21%), and residual aneurysm filling in 31 (31%). Follow-up imaging performed in 85 (90.4%) of a possible 94 aneurysms showed complete occlusion of 77 aneurysms (90.6%), residual neck in 3 (3.5%), and residual filling in 5 (5.9%). Four aneurysms (4.7%) required retreatment. Long-term MRA follow-up revealed stability or progressive thrombosis in 47 (97.9%) of 48 aneurysms. In 11 patients Y-configuration stenting caused only 1 minor complication and provided durable occlusion in all cases.

CONCLUSIONS

Stent-assisted techniques increase the number of aneurysms that may be treated endovascularly and represent an acceptable alternative to craniotomy. Stents provided adequate vessel reconstruction, low complication rates, and good long-term occlusion.

Simple coiling using single or multiple catheters without balloons or stents in middle cerebral artery bifurcation aneurysms

Introduction

We evaluated the outcomes of middle cerebral artery bifurcation (MCAB) aneurysms treated with simple coiling using single or multiple catheters without stents or balloons.

Methods

This study included 100 patients with 103 MCAB aneurysms who underwent a simple coiling procedure without the adjuvant use of stents or balloons. The angiographic clinical outcomes and recurrence of these aneurysms were evaluated.

Results

Of the 103 aneurysms, 102 (99.0 %) aneurysms were successfully treated with simple coiling. One patient died from the consequences of a procedural aneurysm rupture. The treatment-associated permanent morbidity and mortality rates were 0 and 1.0 %, respectively. Post-coiling angiograms showed 28 complete occlusions (27.2 %), 60 neck remnants (58.3 %), and 14 partial occlusions (13.6 %). A follow-up angiography (median duration, 30 months; range, 3–73 months) was performed in 80 lesions. Recanalisation was found in 28 lesions (35.0 %), of which 6 were complete occlusions, 18 were neck remnants, and 4 were partial occlusions, as determined by post-coiling angiograms. Among these lesions, 14 major recurrences were retreated with coiling (n = 12) and clipping (n = 2) without complications. Age (odds ratio [OR], 0.93; 95 % confidence interval [CI], −0.11 to −0.01; p = 0.03), the presence of a rupture (OR, 3.89; 95 % CI, 0.12 to 2.60; p = 0.03), and a wide aneurysm neck (OR, 6.40; 95 % CI, 0.57 to 3.14; p = 0.005) were significantly associated with the aneurysm recurrence, as determined by multivariable analyses.

Conclusion

Our study suggests that simple coiling of MCAB aneurysms is feasible and safe; however, it has limitations in durability, particularly in ruptured or wide-necked aneurysms and in young patients.

Endovascular treatment for saccular aneurysms of the proximal (M1) segment of the middle cerebral artery

BACKGROUND

Saccular aneurysms located at the M1 segment of the middle cerebral artery (MCA) are uncommon, and endovascular treatment (EVT) for them is not well documented. We performed this study to evaluate the feasibility, safety, and efficacy of EVT for proximal (M1) segment saccular aneurysm of the middle cerebral artery.

METHODS

Of 153 MCA aneurysms between January 2007 and September 2011, 29 patients with 29 M1 segment saccular aneurysms were treated at our institution via endovascular approach. There were 14 men and 15 women with a mean age of 56.2 years (range 36-78 years).

RESULTS

Treatments were successful in 28 (96.6 %) cases, including coiling alone in 19 patients, stent-assisted coiling in 8, and balloon-assisted coiling in 1. In the failed case, coiling was not successful, and only a stent was deployed. Immediate angiograms showed total occlusion in 13 patients, neck remnant in 7, partial occlusion in 8, and contrast stasis in the patient who was not coiled successfully. Two (6.9 %) procedure-related complications occurred, including early temporal branch (ETB) obliteration in one patient and lenticulostriate artery (LSA) occlusion in the other one, which resulted in hemiparalysis of one patient. Three patients died from initial severe SAH during hospitalization. One patient died from heart infarction 1 month after operation. Twenty-three of 25 surviving patients underwent follow-up cerebral angiography at intervals ranging from 1 to 21 months (mean, 7.3 months). The result showed 14/23 (60.9 %) aneurysms were completely occluded, 3/23 (13 %) were recanalized, and others were stable or improved. The clinical follow-up (mean, 22.5 months) of all survived patients demonstrated no neurologic deterioration or rebleeding.

CONCLUSION

Our preliminary experience demonstrates that EVT for proximal MCA aneurysm is feasible and safe. However, more adequate follow-up is required to evaluate its long-term results.

Aneurysm treatment in Europe 2010: an internet survey

BACKGROUND

Aneurysm (AN) treatment appears to differ from country to country and even from centre to centre. Therefore we decided to conduct a survey in order to better understand the "state of the art" in aneurysm treatment in Europe. The primary aim was to understand the roles of clipping and coiling in aneurysm treatment.

METHODS

An interactive form was sent to major European neurosurgical centres. The responses relating to AN location, status (ruptured/unruptured) and treatment modality were divided with regard to the volume of cases and the centre's geographical location.

RESULTS

Responses were received from 96 European centres. The main finding was that clipping was used significantly more often in Eastern Europe than in the rest of Europe to treat ruptured ANs of the anterior circulation. Almost all ruptured ANs across all locations are treated actively. The treatment of unruptured aneurysms of the anterior circulation is similar. The median relating to observed unruptured ANs across the Europe was 10 %. Posterior circulation ANs are treated predominantly by coiling, regardless of aneurysm status or geographical location. The average number of coilers versus surgeons per centre was 2.5:3.0 in Western, 1.9:3.6 in Southern, 1.9:4.3 in Eastern and 2.7:3.1 in Northern Europe.

CONCLUSIONS

The way in which intracranial aneurysms are treated appears to correlate with the economic development of European countries. It is probably also affected by the lack of experienced coilers in Eastern Europe.

Y-configuration stent placement (crossing and kissing) for endovascular treatment of wide-neck cerebral aneurysms located at 4 different bifurcation sites

BACKGROUND AND PURPOSE

The Y-stent technique, including crossing-Y and kissing-Y, is a promising therapeutic option for some complex bifurcation aneurysms. Here, its efficacy and safety are evaluated on the basis of 11 bifurcation aneurysms.

MATERIALS AND METHODS

A retrospective review was conducted for all patients who underwent endovascular treatment of aneurysms in our department between January 2009 and June 2011 to identify and analyze cases with bifurcation aneurysms reconstructed by using Y-stents.

RESULTS

Eleven patients (4 ruptured and 7 unruptured aneurysms) were identified (4 men, 7 women) with a mean age of 60.4 years. Nine aneurysms (2 AcomAs, 3 MCA-Bifs, 1 PcomA, 3 BA apexes) were treated by using the crossing-Y technique, and 2 (both BA apexes) were treated with the kissing-Y technique, achieving complete occlusion in 6 aneurysms, residual neck in 4, and partial occlusion in 1. Perioperatively, a single thromboembolic event occurred in 1 case without neurologic deficit, which required a salvaging second stent implantation. Means of 9.9 months of angiographic and 13.7 months of clinical follow-up were available. As a result, 9 (81.8) aneurysms were completely occluded, 1 with a residual neck remained stable, and 1 residual aneurysm sac was recanalized, which was retreated and achieved a complete occlusion. All patients were independent with an mRS score of 0-1 at discharge and follow-up.

CONCLUSIONS

In selected patients, the reconstruction of bifurcation aneurysms by using the Y-stent can be successfully achieved with satisfactory midterm results.

Stent-assisted coil embolization of complex wide-necked bifurcation cerebral aneurysms using the "waffle cone" technique. A review of ten consecutive cases

Endovascular treatment of complex, wide-necked bifurcation cerebral aneurysms is challenging.  Intra/extra-aneurysmal stent placement, the "waffle cone" technique, has the advantage of using a single stent to prevent coil herniation without the need to deliver the stent to the efferent vessel. The published data on the use of this technique is limited. We present our initial and follow-up experience with the waffle cone stent-assisted coiling (SAC) of aneurysms to evaluate the durability of the technique. We retrospectively identified ten consecutive patients who underwent SAC of an aneurysm using the waffle cone technique from July 2009 to March 2011. Clinical and angiographic outcomes after initial treatment and follow-up were evaluated. Raymond Class I or II occlusion of the aneurysm was achieved in all cases with the waffle cone technique. No intraoperative aneurysm rupture was noted. The parent arteries were patent at procedure completion. Clinical follow-up in nine patients (median 12.9 months) revealed no aneurysm rupture. Two patients had a transient embolic ischemic attack at 18 hours and three months after treatment, respectively. Catheter angiography or MRA at six-month follow-up demonstrated persistent occlusions of aneurysms in seven out of eight patients. Another patient had stable aneurysm occlusion at three-month follow-up study. Our experience in the small series suggests the waffle cone technique could be performed on complex, wide-necked aneurysms with relative safety, and it allowed satisfactory occlusions of the aneurysms at six months in most cases.

Comparison of devices used for stent-assisted coiling of intracranial aneurysms

Introduction

Two self-expandable stents, the Neuroform and the Enterprise stent, are widely used for stent-assisted coiling (SAC) of complex shaped intracranial aneurysms. However, comparative knowledge about technical feasibility, peri- and post-procedural morbidity and mortality, packing densities as well as follow-up data is limited.

Material and Methods

We conducted a retrospective study to investigate differences in aneurysms stented with the Enterprise or Neuroform stents. Angiographic follow-up (mean 19.42 months) was available in 72.6% (61/84) of aneurysms treated with stent-assisted coiling. We further sought to compare stent-assisted coiling to a matched patient population with aneurysms treated by conventional coil embolization.

Results

The stenting success rate of the Enterprise was higher compared to the Neuroform stent (46/48 and 42/51, respectively). In 5 of 9 cases in which the Neuroform stent was not navigable to the landing zone, we successfully deployed an Enterprise stent instead. Eventually, 42 aneurysms were coiled after stenting in each group. We observed no significant differences in peri-procedural complication rate, post-procedural hospital stay, packing density, recurrence rate or number of in-stent stenosis. Strikingly, 36.1% of followed aneurysms in the SAC group showed progressive occlusion on angiographic follow-up imaging. The packing density was significantly higher in aneurysms treated by SAC as compared to conventionally coiled aneurysms, while recanalization rate was significantly lower in the SAC group.

Conclusion

The procedural success rate is higher using the Enterprise, but otherwise both stents exhibited similar characteristics. Lower recurrence frequency and complication rates comparable to conventional coil embolization emphasize the importance of stent-assisted coiling in the treatment of complex aneurysms. Progressive occlusion on angiographic follow-up was a distinct and frequent observation in the SAC group and may in part be due to flow diversion.

Stent application for the treatment of cerebral aneurysms

Rapid and striking development in both the techniques and devices make it possible to treat most of cerebral aneurysms endovascularly. Stent has become one of the most important tools in treating difficult aneurysms not feasible for simple coiling. The physical features, the dimensions, and the functional characteristics of the stents show considerable differences. There are also several strategies and tips to treat difficult aneurysms by using stent and coiling. Nevertheless, they require much experience in clinical practice as well as knowledge of the stents to treat cerebral aneurysms safely and effectively. In this report, a brief review of properties of the currently available stents and strategies of their application is presented.

A versatile method for treating intracranial wide-neck aneurysms: catheter-assisted technique of three variations

Successful management of aneurysms of complex morphology depends primarily on adjunct use of balloons or stents. However, these two methods are technically demanding and have higher complication rates. As an alternative to these two techniques, we have used a catheter-assisted technique with a number of cases. It is simple, versatile, and less demanding technically. This technique should be considered as an alternative strategy in cases of wide-necked aneurysms.