Endovascular treatment of anterior communicating artery aneurysms: a systematic review and meta-analysis

A single-center comparative study with large sample size on stent-assisted coiling versus coiling alone for the ruptured anterior communicating artery aneurysms: Analysis of safety, efficacy, and prognosis based on propensity score matching

OBJECTIVE

To compare the safety, efficacy, and prognosis of stent-assisted coiling (SAC) versus coiling alone (CA) in the treatment of ruptured anterior communicating artery aneurysms (ACoAAs).

METHODS

The clinical and follow-up data of ruptured ACoAAs treated with endovascular treatment in our center from January 2011 to January 2021 were retrospectively collected. Patients were divided into an SAC group and a CA group based on whether stents were used, after which the two groups were matched for propensity scores. The general clinical data, embolization effect, perioperative complications, clinical, and follow-up results after matching were compared.

RESULTS

A total of 354 patients were enrolled, of whom 147 patients (41.5%) received SAC and the rest received CA. Comparison baseline of two groups showed that patients with a larger diameter, wide neck, irregular morphology, and anterior direction were more likely to receive SAC. After propensity score matching, 113 patients were included in each group. Immediately postoperative angiography results showed that the complete embolization rate of patients in the SAC group was significantly lower than that in the CA group (62.8% vs. 76.1%, p = 0.03). There were no significant differences between the two groups in the incidence of perioperative complications, mortality, poor prognosis at discharge or follow-up, mid-term complete occlusion rate and recurrence rate.

CONCLUSION

The stent-assisted treatment of ruptured ACoAAs did not increase the risk of perioperative complications or the probability of poor prognosis, indicating that SAC treatment of ruptured ACoAAs is safe and feasible and has a reliable mid-term cure rate.

Onyx prevents the bleeding of ruptured aneurysms during interventional embolization

Endovascular treatment has been acknowledged as an effective treatment for intracranial aneurysms, showcasing favorable clinical outcomes and providing robust protection against rebleeding and rupture. Notably, during the endovascular procedure, significant complications include intraprocedural aneurysmal rupture (IAR) induced by microcatheters, microguidewires, or spring coils, along with thromboembolic events, significantly escalating patient mortality and disability. Current approaches against for IARs involve various strategies such as heparin reversal, compression of the common carotid artery or upstream soft guidewire to mitigate blood flow, management of intracranial pressure and blood pressure, and balloon-assisted or unassisted rapid dense embolization of the aneurysm. Nevertheless, these measures may prove insufficient in halting hemorrhage, especially in scenarios where additional coils cannot be added for dense embolization due to inherent limitations. In this context, we introduce a novel strategy for the prompt, safe, and effective cessation of aneurysm bleeding, which involves injecting an appropriate quantity of Onyx into the aneurysm through a microcatheter while safeguarded by an aneurysm-carrying arterial braided stent. Initially, we attempted dense embolization by filling multiple coils. However, in cases where continued coil filling proved unfeasible or failed to sufficiently prevent contrast agent extravasation, we opted for Onyx injection into the aneurysm. Utilizing Onyx effectively prevented further blood extravasation without adversely impacting the aneurysm-carrying artery or distal vessels, leading to favorable prognoses for all patients. This article delineates our embolization strategy, highlighting the efficacy and safety of Onyx injection as an alternative or complementary measure in managing complications arising from endovascular coil embolization.

Current state of endovascular treatment of anterior cerebral artery aneurysms

The locations of anterior cerebral artery (ACA) aneurysms vary, and various aneurysms can occur along the course of the ACA. Ruptured and some unruptured ACA aneurysms may require aggressive treatment to avoid bleeding or rebleeding. Although open surgery is an effective treatment for ACA aneurysms, endovascular treatment (EVT) is becoming an alternative treatment in select cases. EVT techniques for ACA aneurysms often vary and are performed on a case-by-case basis according to the nature and location of the aneurysm. To better understand the EVT strategy for ACA aneurysms, it is necessary to review EVT for ACA aneurysms. In this review, the following topics are discussed: ACA anatomy and anomalies, classifications of ACA aneurysms, the natural history of ACA aneurysms, open surgery and EVT statuses for ACA aneurysms, EVT techniques for various ACA aneurysms, and the prognosis and complications of EVT for ACA aneurysms. According to our review and experience, traditional coiling EVT is still the preferred therapy for most ACA aneurysms. For A1 aneurysms, EVT is challenging. After the selection of appropriate cases, deployment of a flow diverter and Woven EndoBridge device can result in a good prognosis for patients with ACA aneurysms. In addition, parent artery occlusion can be used to treat A1 aneurysms with good collateral circulation and some distal ACA aneurysms. In general, EVT is gaining popularity as an alternative treatment option for ACA aneurysms.

The safety and clinical outcomes of endovascular treatment versus microsurgical clipping of ruptured anterior communicating artery aneurysms: a 2-year follow-up, multicenter, observational study

Background and objective

Current data on the optimal treatment modality for ruptured anterior communicating artery (AComA) aneurysms are limited. We conducted this multicenter retrospective study to evaluate the safety and clinical outcomes of endovascular treatment (EVT) and microsurgical clipping (MC) for the treatment of ruptured AComA patients.

Methods

Patients with ruptured AComA aneurysms were screened from the Chinese Multicenter Cerebral Aneurysm Database. Propensity score matching (PSM) was used to adjust for baseline characteristic imbalances between the EVT and MC groups. The safety outcomes included total procedural complications, procedure-related morbidity/death and remedial procedure for complication. The primary clinical outcome was 2-year functional independence measured by the modified Rankin scale (mRS) score.

Results

The analysis included 893 patients with ruptured AComA aneurysms (EVT: 549; MC: 346). PSM yielded 275 pairs of patients in the EVT and MC cohorts for comparison. Decompressive craniectomy being more prevalent in the MC group (19.3% vs. 1.5%, p < 0.001). Safety data revealed a lower rate of total procedural complications (odds ratio [OR] = 0.62, 95% CI 0.39-0.99; p = 0.044) in the EVT group and similar rates of procedure-related morbidity/death (OR = 0.91, 95% CI 0.48-1.73; p = 0.880) and remedial procedure for complication (OR = 1.35, 95% CI 0.51-3.69, p = 0.657) between the groups. Compared with that of MC patients, EVT patients had a greater likelihood of functional independence (mRS score 0-2) at discharge (OR = 1.68, 95% CI 1.14-2.50; p = 0.008) and at 2 years (OR = 1.89, 95% CI 1.20-3.00; p = 0.005), a lower incidence of 2-year all-cause mortality (OR = 0.54, 95% CI 0.31-0.93; p = 0.023) and a similar rate of retreatment (OR = 1.00, 95% CI 0.23-4.40; p = 1.000).

Conclusion

Clinical outcomes after treatment for ruptured AComA aneurysms appear to be superior to those after treatment with MC, with fewer overall procedure-related complications and no increase in the retreatment rate. Additional studies in other countries are needed to verify these findings.

Endovascular Treatment of Small Anterior Communicating Artery Aneurysms: Safety and Efficacy in a Contemporary Cohort

BACKGROUND AND OBJECTIVES

Endovascular treatment (EVT) of small anterior communicating artery (ACoA) aneurysms accompanies a high risk of intraprocedural rupture (IR) because of anatomic location and aneurysm orientation. In this study, we aimed to investigate the safety and efficacy of EVT for small ACoA aneurysms in a contemporary cohort.

METHODS

ACoA aneurysms treated at the Medical University of South Carolina between April 2012 and March 2022 were retrospectively analyzed. Periprocedural baseline characteristics, aneurysm size, and clinical and radiological outcomes were collected. Aneurysms were dichotomized into <4 and ≥4 mm in maximum size. The IR rate, favorable occlusion rate (Raymond-Roy I and II), and the favorable outcome defined as modified Rankin Scale 0-2 were compared.

RESULTS

A total of 174 patients were identified, of whom 111 (63.8%) were female, and the median age was 57.7 (interquartile range 50.6-69.6) years. 98 (56.3%) aneurysms were ruptured, and 53 (30.5%) were <4 mm. IR was not observed in unruptured ACoA aneurysms, and there was no significant difference in the IR rates between <4 mm and ≥4 mm ruptured aneurysms (6.5% vs 4.5%, P = .65). Favorable occlusion rate and favorable outcome were observed in 94.7% and 78.2% of patients, respectively.

CONCLUSION

EVT of small ACoA aneurysms is safe and effective.

Safety and Efficacy of Flow Diverters for Treatment of Unruptured Anterior Communicating Artery Aneurysms: Retrospective Multicenter Study

BACKGROUND

The anterior communicating artery (AComm) region is the most common site of intracranial aneurysms, with increased rupture risk compared with other locations. Overall, flow diverters present as a safe and efficacious treatment for intracranial aneurysms, but there is paucity of data for their use in the treatment of unruptured AComm aneurysms. We present the largest multicentric analysis evaluating the outcomes of flow diverters in AComm aneurysm treatment.

METHODS

Databases from 10 centers were retrospectively reviewed for unruptured AComm aneurysms treated with flow diverters. Demographics, clinical presentation, radiographic characteristics, procedural complications, and outcomes were assessed.

RESULTS

A total of 144 patients harboring 147 AComm aneurysms were treated between January 2012 and December 2021. Seventy-four were women (51.4%) and median age was 60 (IQR 50-67) years. All were unruptured AComm aneurysms. Half of the cohort had similar anterior cerebral artery sizes (51.4%). The most common morphology was saccular (94.6%), with a branch involvement in 32.7% of cases. Median vessel diameter was 2.4 mm, and the Pipeline Flex was the most prevalent device (32.7%). Median follow-up time was 17 months, with complete occlusion in 86.4% at the last follow-up. Functional independence (modified Rankin Scale score 0-2) was reported in 95.1%. Intraprocedural complications occurred in 5.6%, and postoperative complications were noted in 9.7% of cases. Combined major complication and mortality rate was 2.1%.

CONCLUSIONS

Our study suggests that flow diverters are a useful treatment for AComm aneurysms. Mid-term results indicated favorable aneurysm occlusion with a good safety profile. Additional prospective studies with longer follow-up periods and independent adjudication are warranted to better assess these results.

Endovascular Treatment of Anterior Communicating Artery Aneurysms: A Single-Center Experience from a Developing Country

Objective  In recent years, endovascular methods have been developed to treat intracranial aneurysms. To date, results of endovascular treatment (EVT) for anterior communicating aneurysms (ACoAs) have never been investigated in Iran. Thus, we sought to assess the mid-term angiographic and clinical outcomes of patients with ACoAs who underwent EVT in a tertiary center. Materials and Methods  Electronic health documents of patients with ACoAs who underwent EVT from March 2019 to July 2021 were retrospectively reviewed. Demographic and clinical characteristics of patients, procedural and clinical complications along with immediate and 12 months' postprocedural angiographic and clinical results were included in the analysis. Aneurysm occlusion status was classified based on the Raymond-Roy Occlusion Classification (RROC), and clinical outcomes were assessed using the modified Rankin Scale (mRS). Results  Of 38 patients with 38 ACoAs, 32 patients (84.21%) presented with subarachnoid hemorrhage of whom 23 (60.52%) had ruptured ACoAs. EVT included simple coiling in 29 patients (76.32%), balloon-assisted coiling in 6 (15.79%), and stent-assisted coiling in 3 (7.89%). Immediate and 12-month postprocedural angiograms demonstrated complete/near-complete occlusion (RROC I and II) in 32 (84.21%) and 35 patients (97.22%), respectively. Periprocedural complications occurred in five patients (13.15%), and the mortality rate was 5.26%. Thirty-two patients (84.21%) had favorable outcomes (mRS 0-2) at the last follow-up. Conclusion  EVT is a safe and beneficial procedure with favorable mid-term clinical and angiographic outcomes for ACoAs. Our results can lay the foundation for further studies in developing countries and are satisfactory enough for neurointerventionists to put EVT on the therapeutic agenda of ACoAs.

Unruptured Anterior Communicating Artery Aneurysms: Management Strategy and Results of a Single-Center Experience

Although anterior communicating artery (AComA) unruptured intracranial aneurysms (UIAs) comprise one of the largest aneurysm subgroups, their complex adjacent neurovasculature and increased risk of rupture impede optimal management. In the present study, we analyzed the results of our diverse strategy in AComA UIAs with the additional goal of assessing the risk of treatment and the incidence of hemorrhage. We analyzed 131 patients, of which each was assessed by a multidisciplinary neurovascular team and assigned to observation (45.8%), endovascular treatment (34.4%) or microsurgery (19.8%). Median aneurysm sizes were 3, 7.2 and 7.75 mm, respectively. In the observation group, four (7.1%) aneurysms (initially <5 mm) grew over a median time of 63.5 months and were treated endovascularly. We found that fewer patients in the observation group were smokers (p = 0.021). The aneurysm size ratio was different between the combined treatment versus the observation group (p < 0.0001). Noteworthily, there were no hemorrhages in the observational group. Mortality for all patients with available follow-up was 2.4% (3/124) and permanent morbidity was 1.6% (2/124) over a mean follow-up of 64.2 months. These compelling rates refer to a high-risk group with potentially devastating consequences in which we have decreased the annual risk of hemorrhage to 0.14%.

Surgery or Endovascular Treatment in Patients with Anterior Communicating Artery Aneurysm: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVE

Although randomized controlled trials have compared surgery versus endovascular treatment for intracranial aneurysms, the literature is sparse in terms of subgroup analysis for anterior communicating artery (ACoA) aneurysm management. This systematic review and meta-analysis sought to compare surgical versus endovascular treatment for ACoA aneurysms.

METHODS

Medline, PubMed, and Embase were searched from inception to December 12, 2022. Primary outcomes were post-treatment modified Rankin Scale (mRS) >2 and mortality. Secondary outcomes were aneurysm obliteration, retreatment and recurrence, rebleeding, technical failure, vessel rupture, aneurysmal subarachnoid hemorrhage-related hydrocephalus, symptomatic vasospasm, and stroke.

RESULTS

Eighteen studies yielded 2368 patients, from which 1196 (50.5%) and 1172 (49.4%) patients underwent surgery and endovascular treatment, respectively. The odds ratio (OR) of mortality was similar in total (OR = 0.92 [0.63-1.37], P = 0.69), ruptured (OR = 0.92 [0.62-1.36], P = 0.66), and unruptured cohorts (OR = 1.58 [0.06-39.60], P = 0.78). The OR of mRS > 2 was similar in total (OR = 0.75 [0.50-1.13], P = 0.17), ruptured (OR = 0.77 [0.49-1.20], P = 0.25), and unruptured cohorts (OR = 0.64 [0.21-1.96], P = 0.44). The OR of obliteration was higher with surgery in the total (OR = 2.52 [1.49-4.27], P = 0.0008) and ruptured cohorts (OR = 2.61 [1.33-5.10], P = 0.005) and unruptured group (OR = 3.46 [1.30-9.20], P = 0.01). The OR of retreatment was lower with surgery in the total (OR = 0.37 [0.17-0.76], P = 0.007) and ruptured cohorts (OR = 0.31 [0.11-0.89], P = 0.03), thought it was similar in the unruptured group (OR = 0.51 [0.08-3.03], P = 0.46). The OR of recurrence was lower with surgery in the total (OR = 0.22 [0.10, 0.47], P = 0.0001), ruptured (OR = 0.16 [0.03, 0.90], P = 0.04), and mixed (un) ruptured cohorts (OR = 0.22 [0.09-0.53], P = 0.0009). The OR of rebleeding in ruptured group was similar (OR = 0.66 [0.29-1.52], P = 0.33). The ORs of other outcomes were similar.

CONCLUSIONS

ACoA aneurysms may be safely treated with either surgery or endovascular treatment, although microsurgical clipping demonstrates higher obliteration rates and lower rates of retreatment and recurrence.

Understanding anterior communicating artery aneurysms: A bibliometric analysis of top 100 most cited articles

Bibliometric analysis is of paramount importance in assessing the research impact wherein studies are ranked on the basis of citations received. It also brings out the excellent contribution of authors and journals in adding evidence for future research. This study aimed at evaluating the top 100 most cited articles on anterior communicating artery (ACoA) Aneurysms. Scopus database was searched using title specific search for the aneurysm of ACoA and top 100 most cited articles along with their authors, author IDs, affiliated institutions, countries and funding bodies were identified. Search yielded 841 articles and top 100 articles were identified to include in this analysis which secured 5615 citations. Citations per year was also calculated to minimize the risk of bias. Maximum citations by any article were 242. The United States was the major contributor to the number of articles while Kessler Institute for Rehabilitation became the highest contributing institution. DeLuca J proved to be a pioneer in this specialized area as he penned 6 studies being first author in 4 of them, making him the most frequent author. National Institutes of Health and the U.S. Department of Health and Human Services were the main funding bodies. Subcategory analysis revealed, 50% studies provided evidence for the treatment and the surgical outcome of the aneurysm. Studies like these can aid in better neurological and neurosurgical management in decision making of ACoA aneurysm.

Flow Diverter Devices in the Treatment of Anterior Communicating Artery Region Aneurysms: Would the Regional Anatomy and the Aneurysm Location Affect the Outcomes?

BACKGROUND

In this study, the authors evaluated the efficacy and the safety of flow diverter devices (FDD) in anterior communicating artery (ACoA) region aneurysms, focusing on anatomical factors that could affect the outcome, such as the location of the aneurysm along the ACoA (centered on ACoA or decentered on the A1-A2 junction) and the anatomy of the ACoA region.

METHODS

Clinical, procedural and follow-up data were analyzed. Aneurysms were classified according to the location along the ACoA (centered or decentered on the A1-A2 junction) and on the basis of the anatomical configuration of the ACoA region. Safety was assessed by recording intraprocedural, periprocedural and delayed complications to determine the morbidity and mortality rates. The functional outcome was evaluated with the modified Rankin scale (mRS) prior to and after the endovascular procedure. To assess the efficacy, midterm and long-term clinical, angiographic and cross-sectional imaging follow-ups were recorded. Subgroup analysis according to the different ACoA regional anatomical configurations and the ACoA aneurysm locations were performed.

RESULTS

33 patients (17 males; 16 females) with ACoA region aneurysms were treated with FDDs. 27 aneurysms were located at the A1-A2 junction (82%) while the remaining six aneurysms were centered on the ACoA. No mortality was recorded. The overall morbidity rate was 6% (2/33 procedures). Major complications occurred in 33% (2/6) of ACoA aneurysms and in the 0% of A1-A2 junction aneurysms. Mid-term and long-term neuroimaging follow-ups showed the occlusion of the aneurysm in 28/33 cases (85%). Complete occlusion rates were 93% in the A1-A2 junction aneurysms and 50% in ACoA aneurysms.

CONCLUSIONS

The FDD is a safe and effective tool that can be used in the treatment of selected cases of ACoA region aneurysms. The location of the aneurysm along the ACoA and the regional anatomy of the ACoA complex could affect the efficacy and safety.

Outcome of ruptured anterior communicating artery aneurysm treatment compared between surgical clipping and endovascular coiling: A single-center analysis

The optimal treatment modality for ruptured anterior communicating artery (ACoA) aneurysms is unclear. Therefore, in this study, we aimed to compare the outcomes of endovascular coiling and surgical clipping to treat ruptured ACoA aneurysms. A retrospective analysis of 213 consecutive patients with ruptured AcoA aneurysms, who were treated with coiling or clipping between January 2010 and December 2020, was conducted. Of the 213 patients, 94 and 119 underwent clipping and coiling, respectively. The mean age was higher in the coiling group than in the clipping group (60.3 ± 13.2 vs. 53.5 ± 13.4, P < .001). The mean diameter of the aneurysmal neck was larger in the clipping group (3.4 mm vs. 3.0 mm, P = .022), whereas the dome-to-neck ratio (1.53 ± 0.52 vs. 1.70 ± 0.60, P = .031) and aspect ratio (1.67 ± 0.51 vs. 1.92 ± 0.77, P = .005) were larger in the coiling group. The prevalence of vasospasm was higher in the clipping than in the coiling group (42.6% vs. 26.9%, P = .016). The coiling group had a shorter mean intensive care unit hospitalization (18.3 vs. 12.1, P = .002) and more frequently showed favorable outcomes (Glasgow Outcome Scale 4, 5; 57.4% vs 73.1%, P = .016) compared to the clipping group. Multivariable logistic analysis showed that good initial WFNS grade (odds ratio [OR] = 6.69, 95% confidence interval [CI]: 2.69-16.65, P < .001), treatment with coiling (OR = 3.67, 95% CI: 1.70-7.90, P = .001), and absence of the need for cerebrospinal fluid diversion (OR = 5.21, 95% CI: 2.38-11.39, P < .001) were independent predictors of favorable outcomes in patients with ruptured ACoA aneurysms. Ruptured ACoA aneurysms can be safely and effectively treated using both clipping and coiling modalities. However, it may be beneficial to consider coiling as the first option for treating these aneurysms.

Intra-procedural complications, success rate, and need for retreatment of endovascular treatments in anterior communicating artery aneurysms: a systematic review and meta-analysis

In recent years, intracranial aneurysms have been widely treated with endovascular methods. The anterior communicating artery (Acom) is the most common site of intracranial aneurysms. Despite its effectiveness, endovascular interventions can be associated with various intra-procedural and post-procedural complications. A systematic review of the literature was performed through PubMed, Embase, Scopus, and Web of Sciences databases up to March 18, 2022. The pooled rates of intra-procedural complications, mortality, procedure-related morbidities, the immediate and late aneurysm occlusion, and also the necessity for retreatment were calculated by applying random-effects models. A total of 41 articles with 4583 patients were included in the meta-analysis. The pooled rate of overall intra-procedural complications was 9.6% (95% CI: 7.7 to 11.8%). The initial rupture status and also type of EVT procedure did not affect the overall complication rate. The pooled rate of intra-procedural thrombosis, aneurysm rupture, coil prolapse, and early aneurysm rebleeding were 6.1% (95% CI: 4.5 to 8.2%); 4.2% (95% CI: 3.4 to 5.2%), 4.7% (95% CI: 3.2 to 6.7%), and 2.2% (95% CI: 1.5 to 3.2%), respectively. Our analysis showed that intra-procedural mortality occurred in 1.7% (95% CI: 1.1 to 2.5%) and procedure-related permanent morbidities in 3.3% (95% CI: 2.3 to 4.7%) of patients. Endovascular methods achieved complete and near to complete aneurysm occlusion (Raymond-Roy occlusion classification 1 and 2) in 89.2% (95% CI: 86.4 to 92.5%) of cases post-procedure, and 9.5% (95% CI: 7.3 to 12.4%) of patients needed retreatment due to recanalization in follow-ups. Endovascular treatment can serve as an acceptable method for Acom aneurysms. However, improved endovascular treatment equipment and new techniques provide more satisfactory outcomes for complicated cases.

Clipping Could Be the Best Treatment Modality for Recurring Anterior Communicating Artery Aneurysms Treated Endovascularly

BACKGROUND

The anterior communicating artery (AcoA) is the most common location for intracranial aneurysms.

OBJECTIVE

To present occlusion outcomes, complication rate, recurrence rate, and predictors of recurrence in a large cohort with AcoA aneurysms treated primarily with endosaccular embolization. We also attempt to present data on the most effective treatment modality for recurrent AcoA aneurysms.

METHODS

This is a retrospective, single-center study, reviewing the outcomes of 463 AcoA aneurysms treated endovascularly between 2003 and 2018.

RESULTS

The study cohort consisted of 463 patients. Adequate immediate occlusion was achieved in 418 (90.3%). Independent functional status at discharge was observed in 269 patients (58.0%), and the mortality rate was 6.8% (31). At 6 months, adequate occlusion was achieved in 418 (90.4%). Of all the patients, recurrence was observed in 101 cases (21.8%), and of those, 98 (22.4%) underwent retreatment. The combined frequency of retreatment for the coiling group was 42.4%, which was significantly higher than the 0 incident of retreatment in the clipping group (P < .0001). Among the retreatment cohort, there was a significantly higher subsequent retreatment rate in the endovascular group (0% in the clipping group vs 42.4% in the endovascular group, P < .0001).

CONCLUSION

Coiling with and without stent/balloon assistance is a relatively safe and effective modality for the treatment of AcoA aneurysms; however, in the setting of recurrence, microsurgical reconstruction leads to improved outcomes regarding durable occlusion, thus avoiding the potential for multiple interventions in the future.

Comparing treatment outcomes of various intracranial bifurcation aneurysms locations using the Woven EndoBridge (WEB) device

BACKGROUND

The Woven EndoBridge (WEB) device has Food and Drug Administration approval for treatment of wide-necked intracranial bifurcation aneurysms. The WEB device has been shown to result in adequate occlusion in bifurcation aneurysms overall, but its usefulness in the individual bifurcation locations has been evaluated separately only in few case series, which were limited by small sample sizes.

OBJECTIVE

To compare angiographic and clinical outcomes after treatment of bifurcation aneurysms at various locations, including anterior communicating artery (AComA), anterior cerebral artery (ACA) bifurcation distal to AComA, basilar tip, internal carotid artery (ICA) bifurcation, and middle cerebral artery (MCA) bifurcation aneurysms using the WEB device.

METHODS

A retrospective cohort analysis was conducted at 22 academic institutions worldwide to compare treatment outcomes of patients with intracranial bifurcation aneurysms using the WEB device. Data include patient and aneurysm characteristics, procedural details, angiographic and functional outcomes, and complications.

RESULTS

A total of 572 aneurysms were included. MCA (36%), AComA (35.7%), and basilar tip (18.9%) aneurysms were most common. The rate of adequate aneurysm occlusion was significantly higher for basilar tip (91.6%) and ICA bifurcation (96.7%) aneurysms and lower for ACA bifurcation (71.4%) and AComA (80.6%) aneurysms (p=0.04).

CONCLUSION

To our knowledge, this is the most extensive study to date that compares the treatment of different intracranial bifurcation aneurysms using the WEB device. Basilar tip and ICA bifurcation aneurysms showed significantly higher rates of aneurysm occlusion than other locations.

Endovascular Treatment for Anterior Communicating Artery Aneurysms

Previously, anterior communicating artery aneurysms were considered unsuitable for endovascular treatment. In recent years, however, endovascular treatment has been increasingly performed due to the fact that it is less likely to cause high dysfunction compared to surgery and the treatment has been improved. The International Subarachnoid Aneurysm Trial reported anterior communicating artery aneurysms comprise 45.4% of cerebral aneurysms on which both endovascular treatment and surgery are suitable. The use of the endovascular treatment for anterior communicating artery aneurysms is expected to increase in the future. In this paper, we present cases from our institution based on the characteristics of anterior and distal communicating artery aneurysms, treatment strategies, and treatment indications.

Endovascular treatment of ruptured anterior communicating aneurysms: a 17-year institutional experience with coil embolization

BACKGROUND

Ruptured anterior communicating artery (ACoA) aneurysms can be challenging to treat via an endovascular procedure. This study analyzed retreatment rates and neurological outcomes associated with ruptured ACoA aneurysms treated via endovascular coiling.

METHODS

All patients with a ruptured ACoA aneurysm treated with endovascular coiling from 2003 to 2019 were retrospectively analyzed at a single center. Two comparisons were performed: no retreatment versus retreatment and coil embolization versus balloon-assisted coil embolization. Outcomes included retreatment and neurological outcome assessed via modified Rankin Scale (mRS).

RESULTS

During the study period, 186 patients with ruptured ACoA aneurysms underwent coil embolization. Treatment included standard coil embolization (68.3%, n=127), balloon-assisted coiling (28.5%, n=53), and stent-assisted embolization (2.7%, n=5). Angiographic outcomes were as follows: class I, 65.1% (n=121); class II, 28.5% (n=53); and class III, 6.5% (n=12). There were no aneurysm reruptures after the index procedure. The mean (SD) mRS score was 2.7 (2.0) at last follow-up (mortality, 19 (10%)). Retreatment occurred in 9.7% (n=18). Patients with retreatment were younger with lower-grade subarachnoid hemorrhage and more favorable functional status at discharge. Patients with aneurysms >7 mm (n=36) were significantly more likely to have recurrence (22.2% vs 6.7%, P=0.005).

CONCLUSIONS

Endovascular treatment of ruptured ACoA aneurysms is safe and is associated with low mortality and retreatment rates. Younger patients with favorable functional status and larger aneurysm size are more likely to be retreated. Ruptured aneurysms <4 mm, although prevalent in the study (29%), never required retreatment.

Intracranial hematoma following ruptured anterior communicating artery aneurysms: risk factors, outcome, and prognostic factors after management of coiling first

BACKGROUND

To determine the risk factors for intracranial hematoma (ICH) development following ruptured anterior communicating artery (AcomA) aneurysms and to determine prognostic factors associated with unfavorable outcomes after coiling first.

METHODS

From March 2014 to February 2020, 235 patients with ruptured AcomA aneurysms underwent endovascular treatment in our department. The clinical and radiographic conditions were collected retrospectively. Modified Rankin Scale (mRS) scores of ≤ 2 were accepted as favorable outcomes. Univariate and multivariate logistic regressions were performed to identify significant factors contributing to the incidence of ICHs and to unfavorable outcomes.

RESULTS

Of these 235 patients, 68 had additional ICHs. A posterior orientation of ruptured AcomA aneurysms was the independent variable associated with the incidence of ICHs (OR 3.675; p<0.001). Furthermore, having preoperative Hunt-Hess grades Ⅳ-Ⅴ was an independent variable associated with unfavorable outcomes for ICH patients (OR 80.000; p<0.001). Among the 68 patients with ICHs, 40% (27/68) had Hunt-Hess grades IV-V. Four percent of patients (3/68) underwent surgical hematoma evacuation after the coiling procedure and 15% of the patients (10/68) underwent external ventricular drainage. A favorable outcome was achieved in 72% (49/68) of patients with ruptured AcomA aneurysms. The mortality rate was 21% (14/68) at 6 months.

CONCLUSION

A posterior orientation of ruptured AcomA aneurysms was associated with the incidence of ICHs. Coiling first with surgical management if necessary seems to be an acceptable treatment for ruptured AcomA aneurysms with ICHs. The clinical outcome was associated with the clinical neurological status on admission.

Evaluation of the Safety and Effectiveness of Coil Embolization for Anterior Communicating and Anterior Cerebral Artery Aneurysms

Objective

Endovascular coil embolization for anterior communicating artery (ACoA) and anterior cerebral artery (ACA) aneurysms is associated with high total and near-total occlusion rates, but the complication rate is high. The development of newer endovascular technologies may improve the clinical outcomes. This study investigated the status of endovascular treatment of ACoA and ACA aneurysms by comparing our results with past reports.

Methods

Between January 2006 and December 2018, we investigated 50 patients who were followed for 12 months or longer to clarify the outcomes of coil embolization. The outcomes of embolization were evaluated using time-of-flight MRA. The safety was evaluated based on procedure-related complications that affected clinical outcomes.

Results

Initial assessments demonstrated complete obliteration in 84% (42 of 50 patients) and a residual neck in 14% (7 of 50 patients). Procedure-related complications developed in 12% (6 of 50 patients). The procedure-related morbidity rate was 2% (1 of 50 patients) and there was no procedure-related death. Recanalization was noted in 14% (7 of 50 patients, median follow-up period, 57 months). The recanalized aneurysms were significantly smaller than the stable aneurysms in maximum size (4.3 mm vs. 5.8 mm; p = 0.017) and height (3.7 mm vs. 4.3 mm; p = 0.035).

Conclusion

We demonstrated the safety and effectiveness of endovascular coil embolization for ACoA and ACA aneurysms. The small size of aneurysms may be related to recanalization.

Result of coiling versus clipping of unruptured anterior communicating artery aneurysms treated by a hybrid vascular neurosurgeon

OBJECTIVE

This study will evaluate the outcomes of coiling versus clipping of unruptured anterior communicating artery (A-com) aneurysms treated by a hybrid vascular neurosurgeon to suggest the best protocol of management for these conditions.

METHODS

We retrospectively reviewed the records of 70 patients with an unruptured A-com aneurysm treated with coiling or clipping performed by a hybrid vascular neurosurgeon between March 2012 and December 2019. The patients were dichotomized, into the coil group or clip group. Treatment-related complications, clinical and radiological results were evaluated.

RESULTS

Of the 70 patients identified, 37 underwent coiling and 33 clipping. Procedure-related symptomatic complications occurred in 2 patients (5.4%) in the coil group and 3 patients (9.1%) in the clip group. Poor clinical outcome (modified Rankin Scale [mRS] of 3 to 6) at 6 months of follow-up was seen in only one patient (2.7%) for the coil group, and none for the clip group. The one poor outcome was the result of intra-procedural rupture during coiling. Follow-up conventional angiography data (mean duration, 15.0 months) revealed that the major recanalization rate is 5.6% for the coil group and 10.0% for the clip group.

CONCLUSIONS

Management of A-com aneurysms requires more collaboration between microsurgical clipping and endovascular therapy. Evaluation of patient and aneurysm characteristics by considering the advantages and disadvantages of both techniques could provide an optimal treatment modality. A hybrid vascular neurosurgeon is expected to be a proper solution for the management of these conditions.

Management of unruptured incidentally found intracranial saccular aneurysms

Unruptured intracranial saccular aneurysms occur in 3-5% of the general population. As the use of diagnostic medical imaging has steadily increased over the past few decades with the increased availability of computed tomography (CT) and magnetic resonance imaging (MRI), so has the detection of incidental aneurysms. The management of an unruptured intracranial saccular aneurysm is challenging for both patients and physicians, as the decision to intervene must weigh the risk of rupture and resultant subarachnoid hemorrhage against the risk inherent to the surgical or endovascular procedure. The purpose of this paper is to provide an overview of factors to be considered in the decision to offer treatment for unruptured intracranial aneurysms in adults. In addition, we review aneurysm and patient characteristics that favor surgical clipping over endovascular intervention and vice versa. Finally, the authors propose a novel, simple, and clinically relevant algorithm for observation versus intervention in unruptured intracranial aneurysms based on the PHASES scoring system.

Anterior Communicating Artery Aneurysms: Anatomical Considerations and Microsurgical Strategies

Anterior communicating artery aneurysms account for 23–40% of ruptured intracranial aneurysms and 12–15% of unruptured aneurysms and are the most common intracranial ruptured or unruptured aneurysms. Because they have relatively complex anatomical structures and anatomical variations and are adjacent to important blood vessels and structures, in the process of microsurgical exposure of an Anterior communicating artery aneurysm, attention should be paid not only to the anatomical characteristics of the aneurysm itself but also to the adjacent important blood vessels and perforating arteries; therefore, both surgical clipping and endovascular embolization are serious challenges for neurosurgeons. No matter which treatment is chosen, it is necessary to determine the structure of the Anterior communicating artery and its perforating arteries as well as whether there is a fenestration deformity of the Anterior communicating artery and the relationship between bilateral A1-A2 before surgery. The shape and size of the aneurysm itself and its location relative to adjacent blood vessels also need to be considered to better complete the procedure, and this is especially true for microsurgical clipping. Clarifying the anatomy before surgery is helpful for better selecting the surgical approach and surgical side, which could affect the intraoperative exposure of the aneurysm and adjacent arteries, the surgical difficulty, the resection rate, and the postoperative complications. Therefore, starting with Anterior communicating artery aneurysms and their adjacent structures and variations, this paper reviews the latest progress in surgical treatment based on anatomic specificity as well as the most recent clinical studies.

Comparison between outcomes of endovascular and surgical treatments of ruptured anterior communicating artery aneurysms

INTRODUCTION

The natural history and optimal treatment of previously ruptured anterior communicating artery (ACOM) aneurysms that recur is unknown. This study looks at rates of complications and recurrences of ruptured ACOM aneurysms treated endovascularly and surgically.

MATERIALS AND METHODS

A retrospective observational study of all patients presenting to a single tertiary neurosurgical centre with the first presentation of subarachnoid haemorrhage (SAH) secondary to a ruptured ACOM aneurysm. Data was collected from November 2012 to September 2018 and included baseline demographics, aneurysm characteristics, management, complications, follow-up imaging, and clinical outcomes.

RESULTS

137 patients were included in the study. 113 aneurysms were coiled and 19 were clipped. Management decisions were taken by the multidisciplinary team based on aneurysm morphology or the presence of a haematoma exerting mass effect. There were 187.5 patient-years of follow-up, with a median of 3 years (range 0-73 months). Rates of vasospasm, infarction, CSF diversion, rebleed, length of stay, and functional outcome were not significantly different in the two cohorts. There was a statistically significant increase in the risk of ACOM recurrence in the coiled group when compared to the clipped group at one year (p = .0433). 15 patients required further treatment at a median time of 16 months. In a subgroup group analysis of coiled aneurysms, there was no statistical differences in rates of rebleeding or the functional outcome in those that had aneurysm recurrence and those that did not.

CONCLUSIONS

This study suggests patients with aneurysms treated by endovascular coiling have an increased risk of recurrence versus those treated with clipping. However, the risk of rebleed was not statistically significant. The prevention and impact of recurrence and residual aneurysms remains incompletely understood. Hence, treatment decisions should be taken by patients after they have been given carefully considered recommendations from the multi-disciplinary team.

Microsurgical Treatment of Unruptured Anterior Communicating Artery Aneurysms: Approaches and Outcomes in a Large Contemporary Series and Review of the Literature

BACKGROUND

With advances in endovascular techniques, the relative roles of microsurgery and endovascular therapy in the management of intracranial aneurysms have become less clear, and data regarding treatment-specific outcomes are increasingly important.

OBJECTIVE

To describe our experience with microsurgery in a large series of unruptured anterior communicating artery aneurysms (ACOMMAAs) and detail our treatment decision-making process based on individual aneurysm morphology.

METHODS

We retrospectively reviewed unruptured ACOMMAAs treated microsurgically at our center between 1997 and 2018, recording aneurysm size, surgical approach, occlusion rates, neurological outcomes, and complications.

RESULTS

We treated 300 unruptured ACOMMAAs in 300 patients, mean age 49 yr, 180 (60.0%) female, including 245 (81.7%) small, 50 (16.7%) large, and 5 (1.7%) giant aneurysms. Most underwent a pterional approach (253, 84.3%), with orbitozygomatic or anterior interhemispheric approaches in 35 (11.7%) and 12 (4%), respectively. Greater than 95% occlusion was achieved in 284 (94.7%), 90% to 95% occlusion in 13 (4.3%), and 3 (1.0%) underwent wrapping. Serious complications occurred in 3 patients (1.0%) resulting in 2 deaths (0.7%), and minor complications in 12 (4.0%). At final follow-up, good neurological outcome was observed in 297 (99.0%) patients.

CONCLUSION

Given clinical equipoise regarding optimal treatment of unruptured ACOMMAAs, this work provides a benchmark for achievable microsurgical outcomes. Future surgical/endovascular studies should separate results of ruptured and unruptured lesions and describe aneurysm morphology to allow for better comparison of outcomes between treatments. We suggest that open microsurgery represents an important option for select, morphologically complex ACOMMAAs, and that a multidisciplinary approach offers optimal patient outcomes.

Safety and efficacy of anterior communicating artery compromise during endovascular coil embolization of adjoining aneurysms

OBJECTIVE

In the presence of symmetric A1 flow, the safety and efficacy of compromising the anterior communicating artery (ACoA) during coil embolization of ACoA aneurysms has yet to be evaluated. Herein, the authors describe their experience, focusing on procedural safety.

METHODS

Between October 2012 and July 2017, 285 ACoA aneurysms with symmetric A1 flows were treated at the authors' institution by endovascular coil embolization. Clinical and angiographic outcome data were subjected to binary logistic regression analysis.

RESULTS

ACoA compromise was chosen in the treatment of 71 aneurysms (24.9%), which were completely (n = 15) or incompletely (n = 56) compromised. In the remaining 214 lesions, the ACoA was preserved. Although 9 patients (3.2%) experienced procedure-related thromboembolisms (compromised, 4; preserved, 5), all but 1 patient (with ACoA compromise) were asymptomatic. In multivariate analysis, subarachnoid hemorrhage at presentation was the sole independent risk factor for thromboembolism (OR 15.98, p < 0.01), with ACoA compromise being statistically unrelated. In 276 aneurysms (96.8%) with follow-up of > 6 months (mean 20.9 ± 13.1 months, range 6-54 months), recanalization was confirmed in 21 (minor, 15; major, 6). A narrow (≤ 4 mm) saccular neck (p < 0.01) and ACoA compromise (p = 0.04) were independently linked to prevention of recanalization.

CONCLUSIONS

During coil embolization of ACoA aneurysms, the ACoA may be compromised without serious complications if A1 flows are symmetric. This approach may also confer some long-term protection from recanalization, serving as a valid treatment option for such lesions.

Coil migration during or after endovascular coiling of cerebral aneurysms

BACKGROUND

Coil migration is a complication of endovascular coiling of cerebral aneurysms that has not been well studied.

OBJECTIVE

To report the frequency, risk factors, management strategies, and outcomes of coil migration.

METHODS

This was a retrospective analysis of the clinical and radiological data of patients who underwent cerebral aneurysm coiling complicated by coil migration at five neuroendovascular centers in the United States, Canada, and France between 2008 and 2018.

RESULTS

Eighteen cases of coil migration met our study criteria with an occurrence of 0.3% (18/6071 cases) (procedural migration: 55%, delayed migration: 45%). The mean aneurysm maximal diameter, neck, and height to neck ratio in migration cases were 3.4±1.4 mm (range 2-7.6 mm), 2.4±0.9 mm (range 1.2-4.4 mm), and 1.4±0.4 (range 1-2.15), respectively. The 2 mm diameter coil was the most common (39%, range 1-2.5 mm) migrated coil. The length of the migrated coil was ≤4 cm in 95% of cases.Patients managed conservatively (5/18, 28%) did well. Thromboembolic and/or hemorrhagic complications were noted in 6/10 migration patients treated by endovascular modalities and in all migration patients who underwent surgical treatment (4/4). Three deaths occurred (3/18, 17%) related to high Hunt and Hess grade subarachnoid hemorrhage.

CONCLUSION

Coil migration is an uncommon but important complication of cerebral aneurysm coiling. Small aneurysms, aspect ratio <1.6, and small coils are significant risk factors. Endovascular treatment, such as using a stent retriever, can be considered for procedural, proximal migration, and/or in cases of vessel occlusion. Delayed or distal migration should be managed conservatively.

Safety and Long-term Efficacy of Stent-assisted Coiling for the Treatment of Complex Posterior Cerebral Artery Aneurysms

OBJECTIVE

To evaluate the safety and long-term efficacy of stent-assisted coiling for the treatment of complex posterior cerebral artery (PCA) aneurysms.

METHODS

Angiographic and clinical data of 23 patients harboring 23 complex PCA aneurysms treated with stent-assisted coiling from March 2010 to March 2017 were retrospectively reviewed.

RESULTS

In this study 8 (34.8%) aneurysms were located at the P1 segment, 7 (30.4%) at the junction of P1 and P2 segments (P1-2), and 8 (34.8%) at the P2 segment. The aneurysms were ruptured in 7 cases (30.4%). Thirteen were dissecting in nature, while the other 10 were classical saccular aneurysms. Of the patients, 5 (21.7%) had of history of recent head trauma, immediate angiographic results were Raymond class I in 5 (21.7%) cases, Raymond class II in 8 (34.8%), and Raymond class III in 10 (43.5%). Perioperative complications occurred in one case with occlusion of the PA due to acute in-stent thrombosis without any neurologic deficit at discharge. The last angiographic follow-up (mean 18.7 months) results demonstrated complete aneurysmal occlusion in 20 (87.0%) cases, PA occlusion in 1 (4.3%) and recurrence in 2 (8.7%). Of the two patients with aneurysm recurrence, one was treated by PA occlusion, and the other was treated with two overlapping stents. Clinical follow-up (mean 58.3 months) was available for all 23 patients, 22 (95.7%) patients had good neurologic outcomes (mRS score 0-2), and 1 (4.3%) patient died 7 months after the procedure for unknown reasons.

CONCLUSION

Stent-assisted coiling for the treatment of complex PCA aneurysms is safe and durable with a relatively low rate of complication and a relatively high rate of complete occlusion at long-term follow-up and is a promising alternative strategy for the reconstruction of the PCA.

Effect of Straightening the Parent Vessels in Stent-Assisted Coil Embolization for Anterior Communicating Artery Aneurysms

BACKGROUND

Stent-assisted coil embolization (SAC) for treating anterior communicating artery (AcomA) aneurysms is safe and effective. Straightening of parent vessels by stent placement can lead to progressive thrombosis. We describe our experience with SAC for AcomA aneurysms and demonstrate the effect of straightening the parent vessels.

METHODS

A total of 26 patients with AcomA aneurysms were treated using SAC in our institute between July 2010 and December 2017. Follow-up digital subtraction angiography was performed 6 months after treatment, magnetic resonance angiography was performed every year, and outcomes were analyzed.

RESULTS

From all aneurysms (n = 24), 12 (50.0%) were neck remnant, and 12 (50.0%) were dome-filling types immediately after the procedure. At the 6-month digital subtraction angiography follow-up (n = 22), 13 (59.1%) aneurysms were complete obliteration, 8 (36.4%) were neck remnant, and 1 (4.5%) was dome filling. The median parent vessel angle was measured preoperatively at 98.1°, increased to 124.8° immediately after stent deployment, and further increased to 149.6° at the 6-month follow-up. Progressive thrombosis was observed in 13 of 22 (59.1%) aneurysms. The parent vessel angle change immediately after stent deployment in the progressive thrombosis group tended to be larger than that observed in the no thrombosis group; this change was significant at the 6-month follow-up. The median follow-up term was 18 months. No patients required retreatment.

CONCLUSIONS

Good SAC outcomes were achieved for AcomA aneurysms, and hemodynamic changes related to straightening of the parent vessels is a consideration in SAC.

Procedural Clinical Complications, Case-Fatality Risks, and Risk Factors in Endovascular and Neurosurgical Treatment of Unruptured Intracranial Aneurysms: A Systematic Review and Meta-analysis

Importance

The risk of procedural clinical complications and the case-fatality rate (CFR) from preventive treatment of unruptured intracranial aneurysms varies between studies and may depend on treatment modality and risk factors.

Objective

To assess current procedural clinical 30-day complications and the CFR from endovascular treatment (EVT) and neurosurgical treatment (NST) of unruptured intracranial aneurysms and risk factors of clinical complications.

Data Sources

We searched PubMed, Excerpta Medica Database, and the Cochrane Database for studies published between January 1, 2011, and January 1, 2017.

Study Selection

Studies reporting on clinical complications, the CFR, and risk factors, including 50 patients or more undergoing EVT or NST for saccular unruptured intracranial aneurysms after January 1, 2000, were eligible.

Data Extraction and Synthesis

Per treatment modality, we analyzed clinical complication risk and the CFR with mixed-effects logistic regression models for dichotomous data. For studies reporting data on complication risk factors, we obtained risk ratios (RRs) or odds ratios (ORs) with 95% CIs and pooled risk estimates with weighted random-effects models.

Main Outcomes and Measures

Clinical complications within 30 days and the CFR.

Results

We included 114 studies (106 433 patients with 108 263 aneurysms). For EVT (74 studies), the pooled clinical complication risk was 4.96% (95% CI, 4.00%-6.12%), and the CFR was 0.30% (95% CI, 0.20%-0.40%). Factors associated with complications from EVT were female sex (pooled OR, 1.06 [95% CI, 1.01-1.11]), diabetes (OR, 1.81 [95% CI, 1.05-3.13]), hyperlipidemia (OR, 1.76 [95% CI, 1.3-2.37]), cardiac comorbidity (OR, 2.27 [95% CI, 1.53-3.37]), wide aneurysm neck (>4 mm or dome-to-neck ratio >1.5; OR, 1.71 [95% CI, 1.38-2.11]), posterior circulation aneurysm (OR, 1.42 [95% CI, 1.15-1.74]), stent-assisted coiling (OR, 1.82 [95% CI, 1.16-2.85]), and stenting (OR, 3.43 [95% CI, 1.45-8.09]). For NST (54 studies), the pooled complication risk was 8.34% (95% CI, 6.25%-11.10%) and the CFR was 0.10% (95% CI, 0.00%-0.20%). Factors associated with complications from NST were age (OR per year increase, 1.02 [95% CI, 1.01-1.02]), female sex (OR, 0.43 [95% CI, 0.32-0.85]), coagulopathy (OR, 2.14 [95% CI, 1.13-4.06]), use of anticoagulation (OR, 6.36 [95% CI, 2.55-15.85]), smoking (OR, 1.95 [95% CI, 1.36-2.79]), hypertension (OR, 1.45 [95% CI, 1.03-2.03]), diabetes (OR, 2.38 [95% CI, 1.54-3.67]), congestive heart failure (OR, 2.71 [95% CI, 1.57-4.69]), posterior aneurysm location (OR, 7.25 [95% CI, 3.70-14.20]), and aneurysm calcification (OR, 2.89 [95% CI, 1.35-6.18]).

Conclusions and Relevance

This study identifies risk factors for procedural complications. Large data sets with individual patient data are needed to develop and validate prediction scores for absolute complication risks and CFRs from EVT and NST modalities.

Flow-Diversion Treatment of Unruptured Saccular Anterior Communicating Artery Aneurysms: A Systematic Review and Meta-Analysis

BACKGROUND

Flow diversion for anterior communicating artery aneurysms required further investigation.

PURPOSE

Our aim was to analyze outcomes after treatment of anterior communicating artery aneurysms with flow-diverter stents.

DATA SOURCES

A systematic search of 3 data bases was performed for studies published from 2008 to 2018.

STUDY SELECTION

According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we included studies reporting anterior communicating artery aneurysms treated with flow diversion.

DATA ANALYSIS

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

DATA SYNTHESIS

We included 14 studies and 148 unruptured saccular anterior communicating artery aneurysms treated with flow diversion. The long-term complete/near-complete (O'Kelly-Marotta C-D) occlusion rate was 87.4% (91/105; 95% CI, 81.3%-93.6%; I² = 0%) (mean radiologic follow-up of 11 months). The treatment-related complication rate was 8.6% (14/126; 95% CI, 4%-13.1%; I² = 0%), with morbidity and mortality rates of 3.5% (5/126; 95% CI, 2%-7%; I² = 0%) and 2.5% (2/148; 95% CI, 0.3%-5%; I² = 0%), respectively. Most complications were periprocedural (12/126 = 7%; 95% CI, 3%-11%; I² = 0%). Thromboembolic events were slightly higher compared with hemorrhagic complications (10/126 = 6%; 95% CI, 2%-10%; I² = 0% and 4/126 = 3%; 95% CI, 1%-6%; I² = 0%). Branching arteries (A2 or the recurrent artery of Heubner) covered by the stent were occluded in 16% (7/34; 95% CI, 3.5%-28%; I² = 25%) of cases. Pre- and posttreatment low-dose and high-dose of antiplatelet therapy was not associated with significantly different complication and occlusion rates.

LIMITATIONS

We reviewed small and retrospective series.

CONCLUSIONS

Flow diversion for unruptured saccular anterior communicating artery aneurysms appears to be an effective alternative treatment for lesions difficult to treat with coiling or microsurgical clipping. The treatment-related complication rate was relatively low. However, larger studies are needed to confirm these results.

Angiographic and clinical results of anterior communicating artery aneurysm endovascular treatment

Introduction

The anterior communicating artery (ACoA) is the most common location of intracranial aneurysms, observed in 35% of cases. Endovascular treatment has become an alternative to surgical clipping and the primary method of choice.

Aim

To assess the treatment results of ruptured and unruptured ACoA aneurysms and to assess the incidence of intraprocedural complications and various factors influencing these aspects.

Material and methods

One hundred and eleven embolizations of ACoA aneurysms (80.7% ruptured and 19.3% unruptured) were retrospectively analysed. The methods of embolization were: coiling, balloon-assisted coiling, stent-assisted coiling. Morphology and dimensions of aneurysms were assessed on 3D digital subtraction angiography (DSA) images. Medical records were analysed for patient’s clinical status at admission, intraprocedural complications, follow-up examination and modified Rankin Scale (mRS) score 1 month after discharge.

Results

Immediately after the procedure 56.9% of patients had Raymond-Roy Occlusion Classification (RROC) class I, 37.6% class II and 5.5% class III. The overall intraprocedural complication rate was 6.6%. There were significantly more cases of bleeding (p = 0.012) and coil prolapse (p = 0.012) during the procedures ending with higher packing density. Twenty-eight (25.7%) patients died during hospital stay, 27 (96.4%) with ruptured aneurysm. In the follow-up of 41 patients, RROC was the same or improved in 73.2% of cases and recanalization occurred in 26.8%. Six patients with aneurysm recanalization underwent repeat embolization.

Conclusions

Endovascular embolization of ACoA aneurysms is an effective and safe treatment method. The most powerful factor influencing the incidence of complications is packing density. Superior orientation of the dome, initial incomplete embolization and poor outcome in mRS scale are factors predisposing to ACoA aneurysm recurrence.

Treatment of anterior cerebral artery and anterior communicating artery aneurysms with flow-diversion devices: a systematic review and meta-analysis

INTRODUCTION

To assess the early safety and efficacy of anterior cerebral artery (ACA) and anterior communicating artery (ACoA) aneurysm treatment with flow-diversion devices (FDDs), we performed a systematic review and meta-analysis for these aneurysms.

EVIDENCE ACQUISITION

A literature search was performed by a reference librarian, and, after screening, eight case series were included for meta-analysis. We estimated from each study the cumulative incidence (event rate) and 95% confidence interval (CI) for each outcome. Event rates were pooled in a meta-analysis across studies using the random-effects model; descriptive statistics were reported when relevant.

EVIDENCE SYNTHESIS

129 ACA and ACoA aneurysms from 8 series were included. Technical success rate of 96% (95% CI: 0.93 to 1.00) and a technical complication rate was 3% (95% CI: 0.00 to 0.06). Perioperative rates of ischemic stroke, hemorrhagic stroke, morbidity, and mortality were 3% (95% CI: 0.00 to 0.06), 5% (95% CI: 0.01 to 0.08), 3% (95% CI: 0.00 to 0.06 and 2% (95% CI: 0.00 to 0.05), respectively. The rate of treatment-related, long-term neurological deficit was 4% (95% CI: 0.01 to 0.07). Complete occlusion rate at last radiological follow-up was 79% (95% CI: 0.68 to 0.91).

CONCLUSIONS

FDDs are an acceptable tool for the treatment of ACA and ACoA aneurysms with high rates of technical success and low rates of periprocedural morbidity and mortality. Comparative studies with longer-term follow-up are needed to clarify the role of these devices in the management of ACA and ACoA aneurysms in patients with challenging comorbidities.

A new method to statistically describe microcatheter tip position in patient-specific aneurysm models

BACKGROUND AND PURPOSE

Evidence on how to select microcatheters to facilitate aneurysm catheterization during coil embolization is sparse. We developed a new method to define microcatheter tip location inside a patient-specific aneurysm model as a 3-dimensional probability map. We hypothesized that precision and accuracy of microcatheter tip positioning depend on catheter tip shape and aneurysmal geometry.

MATERIALS AND METHODS

Under fluoroscopic guidance two to three operators introduced differently shaped microcatheters (straight, 45°, 90°) into eight aneurysm models targeting the anatomic center of the aneurysm. Each microcatheter position was recorded with flat-panel CT, and 3-dimensional probability maps of the microcatheter tip positions were generated. Maps were assessed with histogram analyses and compared between tip shapes, aneurysm locations and operators.

RESULTS

Among a total of 530 microcatheter insertions, the precision (mean distance between catheter positions) and accuracy (mean distance to target position) were significantly higher for the 45° tip (1.10±0.64 mm, 3.81±1.41 mm, respectively) than for the 90° tip (1.27±0.57 mm, p=0.010; 4.21±1.60 mm p=0.014, respectively). Accuracy was significantly higher in posterior communicating artery aneurysms (3.38±1.20 mm) than in aneurysms of the internal carotid artery (4.56±1.54 mm, p<0.001).

CONCLUSION

Our method can be used tostatistically describe statistically microcatheter behavior in patient-specific anatomy, which may improve the available evidence guiding microcatheter shape selection. Experience increases the ability to reach the intended position with a microcatheter (accuracy) that is also dependent on the aneurysm location, whereas catheter tip choice determines the variability of catheter tip placements versus each other (precision). Clinical validation is required.

Changing Paradigms in the Endovascular Management of Ruptured Anterior Communicating Artery Aneurysms

BACKGROUND

Approximately 17% of ruptured anterior communicating artery (ACoA) aneurysms were deemed unsuitable for coil embolization during the Barrow Ruptured Aneurysm Trial (BRAT), most commonly due to unfavorable dome-to-neck ratio or small size.

OBJECTIVE

To compare patients treated by coil embolization for ruptured ACoA aneurysms during the trial to those treated after the trial to determine whether advances in endovascular techniques have allowed for effective treatment of these lesions.

METHODS

All cases of ruptured ACoA aneurysms treated by endovascular modalities during BRAT (2003-2007) and post-BRAT (2007-2012) were reviewed for patient and aneurysm characteristics, treatment types, and clinical and angiographic outcomes at 3-yr or last follow-up.

RESULTS

The BRAT ACoA cohort included 39 patients treated with coiling (excluding those crossed over to clipping). The post-BRAT cohort included 93 patients who were significantly older (mean age, 59.5 vs 52.8 yr, P = .005) than the BRAT cohort; there were no significant cohort differences in sex, Hunt and Hess grade, or mean aneurysm size. The use of balloon remodeling was significantly higher in the post-BRAT cohort (31.2% [29/93] vs 5.1% [2/39], P = .001), as was the proportion of wide-necked aneurysms treated (66.7% [62/93] vs 30.8% [12/39], P < .001). There was no significant difference in clinical outcome or retreatment rate between the 2 cohorts (P = .90 and P = .48, respectively).

CONCLUSION

ACoA lesions thought unamenable to endovascular therapy in an earlier randomized trial are now successfully coiled with increased use of adjunctive techniques, without sacrificing patient outcome or treatment durability.

Effect of age on outcomes and practice patterns for patients with anterior communicating artery aneurysms

BACKGROUND

With widespread utilization of noninvasive imaging, small unruptured anterior communicating artery (AcoA) aneurysms are increasingly detected in the general population, particularly in elderly patients. We investigated the association between age and clinical characteristics and outcomes of patients with unruptured AcoA aneurysms.

METHODS

Between January 2008 and May 2016, information on 179 consecutive patients with unruptured AcoA aneurysms was obtained and included demographic data, aneurysm features, risk factors for formation and rupture, treatment type, complications, and follow-up information. A 2-tailed t test was used for continuous data and the chi-square test for categorical variables. Statistical significance was set at P value < 0.05.

RESULTS

There were 76 patients 65 and older (42.5%) and 103 younger than 65 (57.5%). Conservative management was more common in older patients (67.1% vs. 41.7%, P=0.001). Endovascular treatment was more commonly used in the older population (80% vs. 61% of the treated aneurysms in older and younger group, P=0.16). Treatment-related complications were 8% but resulted in permanent neurological deficits in one patient (1.2%). Among conservatively treated aneurysms, three (3.2%) ruptured at follow-up resulting in patient death in two cases (2.4%). All three ruptures occurred in elderly patients.

CONCLUSIONS

With a modern approach that emphasizes endovascular therapy, especially in older individuals, unruptured AcoA aneurysms can be treated with a very low morbidity. Among patients with small aneurysms for which treatment was not deemed indicated or necessary, the rate of rupture at follow-up was not negligible, with 5.8% of older patients experiencing bleeding from the aneurysm.

Stent-assisted embolization of wide-neck anterior communicating artery aneurysms: Review of consecutive 34 cases

OBJECTIVE

We report our experience with stent-assisted coiling of anterior communicating artery aneurysms with special consideration of angiographic and clinical outcomes, retreatment rate and periprocedural complications.

MATERIALS AND METHODS

The analysis included 34 consecutive ruptured and unruptured wide-neck aneurysms. The aneurysm size ranged from 2 to 18mm (mean 5.47). Clinical examinations with the use of modified Rankin Score and angiographic outcomes were evaluated initially post-embolization and at a minimum follow-up of 6 months.

RESULTS

Initial post-treatment complete and near-complete aneurysm occlusion was achieved in 32 (94%) and 2 (6%) cases, respectively. Imaging follow-up, performed in 28 (82%) patients, showed no change in the degree of occlusion in 25 (89%) cases and coil compaction in 3 (11%) patients. Of these, one (3.6%) patient underwent a second coil embolization. The periprocedural severe complication rate was 2.9% (1/35) and was associated with prolonged attempt of retrieval of migrated coil resulting in anterior cerebral artery infarct with serious clinical consequences. In another 3 patients periprocedural adverse events without delayed clinical consequences were noticed. The clinical follow-up evaluation achieved in 33 (97%) patients showed no change in 30 (91%) cases, one patient (3%) with clinical improvement and two (6%) cases of neurological deterioration.

CONCLUSIONS

The use of stent is feasible and effective for coil embolization of wide-necked anterior communicating artery aneurysms. Although periprocedural complications resulting in severe morbidity are rare, they should be noted, since in terms of thromboembolic events some of them presumably have a potential to be avoidable.

Stand-alone coil embolization of anterior communicating artery aneurysms: Efficacy and technical issues

OBJECTIVE

We report our experience with endovascular coiling of anterior communicating artery aneurysms with special consideration of angiographic and clinical outcomes and periprocedural complications.

MATERIALS AND METHODS

The analysis included treatment results of 28 patients with ruptured and unruptured aneurysms. The aneurysm size ranged from 1.8 to 9.8 mm (mean 5.2, SD 1.7). Clinical examinations with the use of modified Rankin Score and angiographic outcomes were evaluated initially post-embolization and at a minimum follow-up of six months.

RESULTS

Initial post-treatment complete and near-complete aneurysm occlusion was achieved in 27 (96%) cases and incomplete occlusion in one (4%) case. Imaging follow-up, performed in 15 (53.6%) patients, showed no change in the degree of occlusion in 11 (73%), coil compaction in one (7%) and progressive occlusion in three (20%) patients. Three (20%) patients underwent a second coil embolization. The procedure-related severe morbidity and mortality rate was 6.4% (2/31). Coil prolapse was present in one (3.2%) case and intraprocedural aneurysm rupture in three (9.6%) cases. The clinical follow-up evaluation achieved in 19 (67.9%) patients showed no change in 17 (89.5%) patients and improvement in two (10.5%) patients.

CONCLUSIONS

Although the efficacy of coil embolization of anterior communicating artery aneurysms is unquestionable and the procedure-related complications are acceptable, they should not be neglected. Further investigations are needed to better understand protective factors, as well as to establish unequivocally appropriate management strategy of these complications.

Stent-Assisted Endovascular Treatment of Anterior Communicating Artery Aneurysms - Literature Review

The anterior cerebral artery is a common location of intracranial aneurysms. The standard coil embolization technique is limited by its inability to occlude wide-neck aneurysms. Stent deployment across the aneurysm neck supports the coil mass inside the aneurysmal sac, and furthermore, has an effect on local hemodynamic and biologic changes. In this article, various management strategies and techniques as well as angiographic outcomes and complications related to stent-assisted endovascular treatment of anterior communicating artery aneurysms are presented. This treatment method is safe and associated with low morbidity and mortality rates.

Treatment of complex anterior cerebral artery aneurysms with Pipeline flow diversion: mid-term results

BACKGROUND

The off-label use of flow diverters in the treatment of distal aneurysms continues to be debated.

OBJECTIVE

To report our multicenter experience in the treatment of complex anterior cerebral artery aneurysms with the Pipeline embolization device (PED).

METHODS

The neurointerventional databases of the four participating institutions were retrospectively reviewed for aneurysms treated with PED between October 2011 and January of 2016. All patients treated for anterior cerebral artery aneurysms were included in the analysis. Clinical presentation, location, type, vessel size, procedural complications, clinical and imaging follow-up were included in the analysis.

RESULTS

Twenty patients (13 female) with 20 aneurysms met the inclusion criteria in our study. Fifteen aneurysms were classified as saccular and five as fusiform (mean size 7.3 mm). Thirteen aneurysms were located in the anterior communicating region (ACOM or A1/2 junction), six were A2-pericallosal, and one was located in the A1 segment. Six patients had presented previously with subarachnoid hemorrhage and had their aneurysms initially clipped or coiled. There was one minor event (a small caudate infarct) and one major event (intraparenchymal hemorrhage). Sixteen of the 20 patients had angiographic follow-up (mean 10 months). Eleven aneurysms were completely occluded, one had residual neck, and four had residual aneurysm filling.

CONCLUSIONS

The treatment of complex anterior cerebral artery aneurysms with the PED as an alternative for patients who are not good candidates for conventional methods is technically feasible and safe. Mid-term results are promising but larger series with long-term follow-up are required to assess its effectiveness.

Predicting intraprocedural rupture and thrombus formation during coiling of ruptured anterior communicating artery aneurysms

Background

Intraprocedural rupture and thrombus formation are serious complications during coiling of ruptured intracranial aneurysms, and they more often occur in patients with anterior communicating artery (ACoA) aneurysms.

Objective

To identify independent predictors of intraprocedural rupture and thrombus formation during coiling of ruptured ACoA aneurysms.

Methods

Between January 2008 and February 2015, 254 consecutive patients with 255 ACoA aneurysms were treated with coiling. We retrospectively reviewed intraoperative angiograms and medical records to identify intraprocedural rupture and thrombus formation, and re-measured aneurysm morphologies using CT angiography images. Multivariate logistic regression models were used to determine independent predictors of intraprocedural rupture and thrombus formation.

Results

Of the 231 patients included, intraprocedural rupture occurred in 10 (4.3%) patients, and thrombus formation occurred in 15 (6.5%) patients. Patients with smaller aneurysms more often experienced intraprocedural rupture than those with larger aneurysms (3.5±1.3 mm vs 5.7±2.3 mm). Multivariate analysis showed that smaller ruptured aneurysms (p=0.003) were independently associated with intraprocedural rupture. The threshold of aneurysm size separating rupture and non-rupture groups was 3.5 mm. Multivariate analysis showed that a history of hypertension (p=0.033), aneurysm neck size (p=0.004), and parent vessel angle (p=0.023) were independent predictors of thrombus formation. The threshold of parent vessel angle separating thrombus and non-thrombus groups was 60.0°.

Conclusions

Ruptured aneurysms <3.5 mm were associated with an increased risk of intraprocedural rupture, and parent vessel angle <60.0°, wider-neck aneurysms, and a history of hypertension were associated with increased risk of thrombus formation during coiling of ruptured ACoA aneurysms.

Stent-assisted coiling versus coiling alone of ruptured anterior communicating artery aneurysms: A single-center experience

OBJECTIVE

Endovascular coiling of anterior communicating artery (ACoA) aneurysms has evolved; however, stent-assisted coiling of ruptured aneurysms remains controversial. We aimed to compare periprocedural complications, angiographic and clinical outcomes after stent-assisted coiling with coiling alone of ruptured ACoA aneurysms.

METHODS

We performed a retrospective review of consecutive 222 patients with ruptured ACoA aneurysms treated with endovascular coiling within 7 days after ictus. Patients were grouped into stent-assisted coiling and coiling alone groups. Baseline characteristics, periprocedural complications, clinical outcomes, and angiographic results were compared between the two groups.

RESULTS

63 (28.4%) patients underwent stent-assisted coiling and 159 (71.6%) underwent coiling alone. There were no statistically significant differences in age, sex, clinical grading and Fisher grade. Larger aneurysms (P=0.002) and wider-neck aneurysms (P<0.001) were more often treated with stent-assisted coiling within 72h (P=0.025). Intraprocedural aneurysm rupture occurred in 6 (9.5%) patients treated with stent-assisted coiling compared with in 5 (3.1%) treated with coiling alone (P<0.048). Thrombus formation occurred in 10 (15.9%) patients after stent-assisted coiling compared with 6 (3.8%) after coiling alone (P=0.002). Stent-assisted coiling achieved a lower rate of immediate occlusion than coiling alone (P=0.045). Postoperative complications, clinical outcomes, and follow-up aneurysm occlusion did not significantly differ.

CONCLUSIONS

Stent-assisted coiling of ruptured ACoA aneurysms was associated with a higher rate of intraprocedural complications and associated with a lower immediate occlusion rate. However, Postoperative complications and clinical outcomes did not differ. Long-term angiographic results require further study.

Eleven Year's Single Center Experience of Endovascular Treatment of Anterior Communicating Artery Aneurysms: Focused on Digital Subtraction Angiography Follow-Up Results

Objective

Anterior communicating artery (AcomA) aneurysms represent the most common intracranial aneurysms and challenging to treat due to complex vascularity. The purpose of this study was to report our experience of endovascular treatment of AcomA aneurysms.

Methods

Between January 2003 and December 2013, we retrospectively reviewed the medical records of 134 AcomA aneurysm patients available more than 6 months conventional angiographic and clinical follow-up results. We focused on aneurismal or AcomA vascular characters, angiographic and clinical follow-up results, and retreatment.

Results

The rate of ruptured cases was 75.4%, and the small (<10 mm) aneurysms were 96.3%. Based on the subtypes defined by dominance of A1, 79 patients (59%) had contralateral A1 hypoplasia or agenesis. The immediate post-procedural angiography confirmed complete occlusion in 75.4%, partial occlusion in 24.6%. Procedure related complications were observed in 25 (18.6%) patients. Most of the adverse events were asymptomatic. Follow-up conventional angiography at ≥6 months was performed in all patients (mean 16.3 months) and major recanalization was noted in 6.7% and regrowth in one case. The aneurysm size (p=0.016), and initial treatment results (p=0.00) were statistically significant risk factors related to aneurysm recurrence. An overall improvement in mRS was observed during the clinical follow-up period and no rebleeding episode occurred.

Conclusion

This study demonstrated that endovascular treatment is an effective treatment modality for AcomA aneurysms with low morbidity. Patients should take long term clinical and angiographic follow-up in order to assess the recurrence and warrant retreatment, especially ruptured, large, and initially incomplete occluded aneurysms.