Stent-Assisted Coiling May Prevent the Recurrence of Very Small Ruptured Intracranial Aneurysms: A Multicenter Study

Treatment for middle cerebral artery bifurcation aneurysms: in silico comparison of the novel Contour device and conventional flow-diverters

Endovascular treatment has become the standard therapy for cerebral aneurysms, while the effective treatment for middle cerebral artery (MCA) bifurcation aneurysms remains a challenge. Current flow-diverting techniques with endovascular coils cover the aneurysm orifice as well as adjacent vessel branches, which may lead to branch occlusion. Novel endovascular flow disruptors, such as the Contour device (Cerus Endovascular), are of great potential to eliminate the risk of branch occlusion. However, there is a lack of valid comparison between novel flow disruptors and conventional (intraluminal) flow-diverters. In this study, two in silico MCA bifurcation aneurysm models were treated by specific Contour devices and flow-diverters using fast-deployment algorithms. Computational fluid dynamic simulations were used to examine the performance and efficiency of deployed devices. Hemodynamic parameters, including aneurysm inflow and wall shear stress, were compared among each Contour device, conventional flow-diverter, and untreated condition. Our results show that the placement of devices can effectively reduce the risk of aneurysm rupture, while the deployment of a Contour device causes more flow reduction than using flow-diverters (e.g. Silk Vista Baby). Besides, the Contour device presents the flow diversion capability of targeting the aneurysm neck without occluding the daughter vessel. In summary, the in silico aneurysm models presented in this study can serve as a powerful pre-planning tool for testing new treatment techniques, optimising device deployment, and predicting the performance in patient-specific aneurysm cases. Contour device is proved to be an effective treatment of MCA bifurcation aneurysms with less daughter vessel occlusion.

Endovascular Coiling of Ruptured Tiny Saccular Intracranial Aneurysms: A Systematic Review and Meta-Analysis

BACKGROUND

The safety and efficacy of endovascular coiling of ruptured tiny saccular intracranial aneurysms (IAs) (≤3 mm) remain unknown.

METHODS

A comprehensive search of PubMed, Embase, Web of Science, and Scorpus databases up to November 15, 2023 was performed. Pooled prevalence was calculated for occlusion rates, recanalization, retreatment, long-term favorable outcome, and procedure-related complications and mortality. Pooled odds ratios were calculated to compare these outcomes between coiling and stent-assisted coiling (SAC).

RESULTS

Forty-two studies with 2166 ruptured tiny saccular IAs treated with coiling were included. The follow-up complete aneurysm occlusion rate was 83.9% (95% CI: 77.2-88.9%). The rates of recanalization and retreatment were 7.7% (95% CI: 5.7-10.2%) and 5.8% (95% CI: 4.5-7.5%). The range of median Hunt and Hess grades was 1.4-2.9 and the favorable outcome rate was 85.6% (95% CI: 81.1-89.2%). The rates of thromboembolism, intraprocedural rupture, and mortality were 4.6% (95% CI: 3.6-5.8%), 5.4% (95% CI: 4.1-7.0%), and 5.6% (95% CI: 4.4-7.2%), respectively. Comparison of coiling and SAC revealed no significant difference, except for a higher likelihood of follow-up complete aneurysm occlusion in SAC (odds ratio [OR] 0.37, 95% CI: 0.17-0.80) and recanalization in the coiling (OR, 3.21 [95% CI, 1.37-7.51]).

CONCLUSIONS

Our meta-analysis demonstrates that coiling for ruptured tiny saccular IA is a feasible, effective, and safe approach that is associated with favorable clinical outcomes in both the short and long term for patients with mild to moderate Hunt and Hess grades.

Coiling Variations for Treatment of Ruptured Intracranial Aneurysms: A Meta-Analytical Comparison of Comaneci-, Stent-, and Balloon-Coiling Assistance Techniques

BACKGROUND

Wide-necked aneurysms represent a challenge for treatment in the setting of acute subarachnoid hemorrhage. Stent-assisted coiling (SAC) and balloon-assisted coiling (BAC) are well-known techniques for treating wide-necked aneurysms. Comaneci-assisted coiling (CAC) is a newer technique involving temporary stent deployment to assist aneurysm coiling. We aim to present the first meta-analysis comparing these treatments of ruptured aneurysms.

METHODS

Following PRISMA guidelines, PubMed and Embase databases were queried from earliest records to July 2022 for literature reporting SAC, BAC, or CAC of ruptured intracranial aneurysms. A meta-analysis of identified articles was performed.

RESULTS

Of the 571 articles queried, 64 articles were included. One study reported BAC and SAC, 8 reported BAC, 52 reported SAC, and 3 reported CAC. These studies comprised 3153 patients with 3207 ruptured aneurysms treated with CAC (161 patients and aneurysms), BAC (330 patients and aneurysms), and SAC (2662 patients, 2716 aneurysms). Rates of periprocedural thromboembolic or hemorrhagic complications, overall or procedure-related mortality, immediate complete occlusion, retreatment, and length of angiographic follow-up did not differ significantly between SAC and BAC. Periprocedural thromboembolic (P = 0.03) and hemorrhagic (P = 0.01) complication rates were higher with BAC than CAC. Periprocedural thromboembolic (P = 0.03) and hemorrhagic (P < 0.0001) complication rates were higher with SAC than CAC. Complete aneurysm occlusion rates (P = 0.033) were higher with CAC than BAC. No significant differences were present in CAC versus BAC or SAC retreatment rates.

CONCLUSIONS

CAC was associated with lower hemorrhagic and thromboembolic complication rates and demonstrated similar complete occlusion and residual retreatment rates to those for BAC and SAC.

Long-term outcomes of coils embolization for superior hypophyseal artery aneurysms

Objective

Superior hypophyseal artery (SHA) aneurysms are intradural, and their rupture can result in subarachnoid hemorrhage. Considering the related surgical difficulty and anatomical restrictions, endovascular treatment (EVT) is considered the most favorable modality for SHA aneurysms; however, the long-term outcomes of EVT have rarely been reported. The study assessed the incidence of and risk factors for recurrence of SHA aneurysms after EVT as well as the correlation factors for SHA aneurysm rupture.

Methods

We included 112 patients with SHA aneurysms treated with EVT at our facility between 2009 and 2020. Here, EVT included non-stent-assisted (simple or balloon-assisted) or stent-assisted coiling. Flow diverter was not included because it was barely used due to its high cost under our national insurance's limitation, and a high proportion of ruptured aneurysms in our series. Univariate and multivariate logistic regression was performed to evaluate the correlation factors for SHA aneurysm rupture, along with the incidence of and risk factors for post-EVT SHA aneurysm recurrence and re-treatment.

Results

In our patients, the mean angiographic follow-up period was 3.12 years. The presence of type IA or IB cavernous internal carotid artery (cICA) was strongly correlated with SHA aneurysm rupture. Recurrence occurred in 17 (13.4%) patients, of which only 1 (1.4%) patient had received stent-assisted coiling. All cases of recurrence were observed within 2 years after EVT. The multivariate logistic regression results showed that ruptured aneurysm and non-stent-assisted coiling were independent risk factors for aneurysm recurrence. Of the 17 cases of aneurysm recurrence, 9 (52.9%) received re-treatment. Moreover, aneurysm rupture was the only factor significantly correlated with re-treatment in multivariate logistic regression. No re-recurrence was observed when a recurrent aneurysm was treated with stent-assisted coiling.

Conclusion

Type I cICA was common factor for aneurysm rupture. Although flow-diverter treatment serves as another suitable technique that was not compared with, coils embolization was effective treatment modality for SHA aneurysms, leading to low recurrence and complication rates, especially with stent use. All cases of recurrence occurred within 2 years after EVT; they were strongly associated with prior aneurysm rupture. Further stent-assisted coiling was noticed to prevent re-recurrence.

Safety and effectiveness of double microcatheter technique in the treatment of ruptured aneurysms of anterior cerebral circulation

Objective

To evaluate the safety and effectiveness of the double microcatheter technique in the treatment of ruptured aneurysms of the anterior cerebral circulation.

Methods

Between 2012 and 2019, 113 patients with ruptured aneurysms of the anterior cerebral circulation were treated using the double microcatheter technique. Clinical records, angiographic results, and procedure-related complications were reviewed. Clinical and angiographic follow-up was performed.

Results

Complete occlusion, neck remnant, and partial occlusion were, respectively, recorded in 56.6, 38.9, and 4.4% of the total cases. For all patients, the incidence of intraoperative complications was 5.3% (6/113), and the overall rate of morbidity was 10.6% (12/113). Before discharge, three patients (2.7%) died. There was no procedure-related mortality. At discharge, favorable outcomes were observed in 79.6% (90/113) of the patients. High Hunt-Hess grades and receiving a craniotomy or external ventricular drainage were risk factors for clinical outcomes at discharge. Clinical follow-up was performed in 91 patients at a mean interval of 14.07 ± 11.68 months. At follow-up, favorable outcomes were observed in 92.3% (84/91) of the patients. Angiographic follow-up was performed in 66 patients at an average of 11.53 ± 11.13 months. The recurrence rate was 37.9%. Of these patients, 13 (19.7%) received retreatment.

Conclusion

The double microcatheter technique can be performed in ruptured aneurysms with high technical success and low morbidity/mortality. However, recurrence remains a problem, and patients should be followed up regularly.

Angiographic Follow-Up for Small Ruptured Intracranial Aneurysm Treated by Endovascular Treatment : Follow-Up Plan and Long-Term Follow-Up Results

Objective

Although endovascular treatment for intracranial aneurysms is considered effective and safe, its durability is still debated. Also, few studies have described angiographic follow-up plan after endovascular treatment of intracranial aneurysm, especially in ruptured cases. Hence, we report the long-term results of follow-up angiography protocol.

Methods

Radiological records of 639 cases of coil embolization with ruptured aneurysms from March 2003 to December 2016 were retrospectively reviewed. Patients who received treatment of a saccular aneurysm less than 7 mm resulted with near complete occlusion were included. Two hundred thirty-eight aneuryms which received the follow-up angiography at least once were enrolled. We classified four periods of follow-up as follows : post-treatment 1 year (defined as the first period), from 1 to 2 years (the second period), 2 to 5 years (the third period), and over 5 years (long-term).

Results

We identified 14 cases (6.4%) of recurrence from 218 aneurysms in follow-up angiography in the first period. Among 143 aneurysms in the second period, five cases (3.5%) of recurrence were identified. There were no findings suspicious of recanalization in 97 patients in the third period. Of the total 238 cases, there were 19 recurrences, for a recurrence rate of 8.0%. Six (31.6%) out of 19 recurrences showed a tendency toward repeat recurrences even after additional treatment. Twenty-eight received long-term follow-up over 5 years and there was no recurrence.

Conclusion

Most of the recurrence were found during the first and the second year. We suggest that at least one digital subtraction angiography examination may be necessary around post-treatment 2 years, especially in ruptured cases. If the angiographic results are favorable at 2 years post-treatment, long-term result should be favorable.

Endovascular Treatment of Ruptured Very Small Intracranial Aneurysms: Complications, Recurrence Rate, and Clinical Outcomes

Objective: The aim of this study was to evaluate the safety and efficacy of endovascular treatment for ruptured very small (≤3 mm) intracranial aneurysms (VSIAs).

Methods: The clinical data and imaging results for 152 patients with VSIAs treated with coil embolization from August 2014 to June 2020 were retrospectively reviewed. The influential factors related to the preoperative complications, aneurysm recurrence, and clinical outcomes for these patients were analyzed.

Results: Among 152 patients with ruptured VSIAs, 90 were treated with coil embolization alone, while 62 were treated with stent-assisted coil embolization. Eighteen patients experienced intra and/or postoperative complications (overall incidence = 11.8%). One person died of intraoperative aneurysm re-rupture and postoperative rebleeding (mortality rate = 0.65%). Twenty patients had various degrees of neurological dysfunction (morbidity rate = 13.1%). Statistical analysis showed that there was no independent risk factor associated with perioperative complications. The rate of complete aneurysm occlusion at discharge and follow-up was 76.3 and 86.2%, respectively. A total of 105 patients underwent digital subtraction angiography during follow-up, and 18 of them experienced postoperative recurrence (recurrence rate = 17.1%). Seven patients were retreated (retreatment rate = 6.7%). The use of stents was the only factor that affected the postoperative recurrence of aneurysm. The incidence of favorable clinical outcomes (Glasgow Outcome Scale score ≥ 4) at discharge and follow-up was 86.2 and 97.1%, respectively. Univariate analysis showed that the preoperative Hunt-Hess grade, CT Fisher grade, and perioperative complications were risk factors for poor clinical outcomes. Multiple logistic regression analysis showed that perioperative complication was the most significant risk factor for the clinical prognosis of patients with ruptured VSIAs.

Conclusion: Endovascular treatment is a safe and efficient approach for ruptured VSIAs. Stent-assisted coiling reduced the recurrence rate of aneurysm without increasing the incidence of perioperative complications. The Hunt-Hess grade, CT Fisher grade, and perioperative complications were independent factors associated with the clinical outcomes of patients with ruptured VSIAs, and perioperative complication was the most significant risk factor for poor prognosis in patients.

Virtual Flow-T Stenting for Two Patient-Specific Bifurcation Aneurysms

The effective treatment of wide necked cerebral aneurysms located at vessel bifurcations (WNBAs) remains a significant challenge. Such aneurysm geometries have typically been approached with Y or T stenting configurations of stents and/or flow diverters, often with the addition of endovascular coils. In this study, two WNBAs were virtually treated by a novel T-stenting technique (Flow-T) with a number of braided stents and flow-diverter devices. Multiple possible device deployment configurations with varying device compression levels were tested, using fast-deployment algorithms, before a steady state computational hemodynamic simulation was conducted to examine the efficacy and performance of each scenario. The virtual fast deployment algorithm based on a linear and torsional spring analogy is used to accurately deploy nine stents in two WNBAs geometries. The devices expand from the distal to proximal side of the devices with respect to aneurysm sac. In the WNBAs modelled, all configurations of Flow-T device placement were shown to reduce factors linked with increased aneurysm rupture risk including aneurysm inflow jets and high aneurysm velocity, along with areas of flow impingement and elevated wall shear stress (WSS). The relative position of the flow-diverting device in the secondary daughter vessel in the Flow-T approach was found to have a negligible effect on overall effectiveness of the procedure in the two geometries considered. The level of interventionalist-applied compression in the braised stent that forms the other arm of the Flow-T approach was shown to impact the aneurysm inflow reduction and aneurysm flow pattern more substantially. In the Flow-T approach the relative position of the secondary daughter vessel flow-diverter device (the SVB) was found to have a negligible effect on inflow reduction, aneurysm flow pattern, or WSS distribution in both aneurysm geometries. This suggests that the device placement in this vessel may be of secondary importance. By contrast, substantially more variation in inflow reduction and aneurysm flow pattern was seen due to variations in braided stent (LVIS EVO or Baby Leo) compression at the aneurysm neck. As such we conclude that the success of a Flow-T procedure is primarily dictated by the level of compression that the interventionalist applies to the braided stent. Similar computationally predicted outcomes for both aneurysm geometries studied suggest that adjunct coiling approach taken in the clinical intervention of the second geometry may have been unnecessary for successful aneurysm isolation. Finally, the computational modelling framework proposed offers an effective planning platform for complex endovascular techniques, such as Flow-T, where the scope of device choice and combination is large and selecting the best strategy and device combination from several candidates is vital.

Application of 3D T1-SPACE combined with 3D-TOF sequence for follow-up evaluation of stent-assisted coil embolization for intracranial aneurysm

OBJECTIVES

To assess 3D T1-SPACE combined with 3D-TOF sequence for follow-up evaluation of stent-assisted coil embolization for intracranial aneurysm.

MATERIALS AND METHODS

Between Oct 2018 and May 2019, we enrolled 25 patients with intracranial aneurysm who underwent stent-assisted coil embolization. All patients were followed up for 6 to10 months after endovascular treatment (EVT) using 3D-TOF MRA, 3D T1-SPACE and DSA to evaluate aneurysm occlusion and parent artery patency.

RESULTS

With regards to aneurysm occlusion, the specificity of 3D-TOF MRA was 86.9% (20/23) and the accuracy was 84% (21/25). There was no statistical significance (P ​= ​0.409) compared with the DSA. The parent artery by 3D-TOF MRA showed that there were 14 patients with grade 3, 8 patients with grade 2 and 3 patients with grade 1. However, 3D T1-SPACE showed that all 25 patients were grade 4, and were clearly displayed without metal artifacts. The comparison of the two MR techniques demonstrated that 3D T1-SPACE was superior to 3D-TOF MRA in the evaluation of parent artery (P<0.001).

CONCLUSIONS

3D T1-SPACE sequence provides better image quality and higher accuracy for evaluating stented parent arteries compared to TOF-MRA. This study also shows that 3D-TOF MRA has a merit to evaluate aneurysm occlusion. The combination of these two modalities can be used as an optional follow-up evaluation after EVT of intracranial aneurysms.

Endovascular Treatment of Tiny Aneurysms With Low-Profile Visualized Intraluminal Support Devices Using a "Compressed" Stent Technique

Objective: To investigate the safety and efficacy of low-profile visualized intraluminal support (LVIS) stent-assisted coiling of intracranial tiny aneurysms using a "compressed" stent technique. Methods: We retrospectively analyzed patients with tiny aneurysms treated in our hospital with LVIS devices using a compressed stent technique. We analyzed patients' imaging outcomes, clinical outcomes, and complications. Results: Forty-two tiny aneurysms in 42 patients were included in this study cohort; 8 patients presented with subarachnoid hemorrhage at admission. The immediate postoperative complete embolization rate was 76.2% (32/42). After an average of 8.5 months of imaging follow-up, the complete embolization rate was 90.5% (38/42), and no aneurysm recanalization occurred. After an average of 24.4 months of clinical follow-up, 95.2% (40/42) of the patients achieved favorable clinical outcomes (modified Rankin scale = 0/1). Operation-related complications occurred in two patients (4.8%); one intraoperative acute thrombosis, and one significant unilateral decreased vision during the postoperative follow-up. Conclusion: LVIS stent-assisted coiling of intracranial tiny aneurysms using a compressed stent technique is safe and effective. Combined stent compression technology is beneficial to maximize the complete embolization of aneurysms and reduce aneurysm recanalization. This study expands the clinical applicability of LVIS stents.

Embolization with Stent-Assisted Technique for Wide-Necked Extremely Small Intracranial Aneurysm with Diameter no more than 2 mm

OBJECTIVE

To investigate the safety and efficacy of embolization with stent-assisted technique for wide-necked extremely small intracranial aneurysms (ESIAs) with diameter no more than 2 mm.

METHODS

From May 2015 through January 2019, 20 wide-necked ESIAs in 19 patients (6 males and 13 females, aged from 38 to 72 years old, average 59 years old) were embolized with stent-assisted technique. All these patients had a total of 29 aneurysms, 7 patients had multiple aneurysms and 1 patient had 2 ESIAs. 12 patients (63.2%) presented with subarachnoid hemorrhage (SAH), 9 of them have a culprit ESIA. The angiographic results before and after operation, procedural complications, and clinical condition with Hunt and Hess grade (H-H) and Fisher grade, as well as Glasgow outcome scale (GOS) at discharge were assessed. Follow-up results were evaluated by computer tomograph angiography (CTA) or digital subtract angiography (DSA).

RESULTS

The mean diameter of aneurysm neck was 1.68 ± 0.21 mm. Complete occlusion with Raymond grade I was achieved in 18 aneurysms (90.9%), 2 aneurysms were subtotal embolization with Raymond grade II (9.1%). All patients were treated with coil embolization with stent-assist technique successfully and all the stents were placed accurately and function well during the procedure. There is no rupture of aneurysm during operation, no coil protrusion to the distal blood vessel, and no cerebral infarction as well. When discharged, all patients recovered well. The follow-up results showed that only one patients with recurrence of aneurysm 27 months after embolization.

CONCLUSION

Embolization with stent-assisted technique for wide-necked ESIAs is safe and effective. However, the follow-up is not long enough in our study and a larger sample size are needed to obtain the long-term efficacy.

Safety and efficacy of complete versus near-complete coiling in treatment of intracranial aneurysms

Objective

This study aimed to evaluate the clinical and angiographic outcomes of aneurysms that were completely or near-completely embolized and ascertain whether complete embolization is important in the stent-assisted coiling (SAC) of intracranial aneurysms.

Methods

This retrospective study enrolled 390 patients (417 aneurysms). Among them, complete (100%) or near-complete (>90%) angiographic obliteration of the aneurysms on immediate angiography was accomplished. Baseline characteristics, complications, angiography follow-up results, and clinical outcomes were analyzed.

Results

Cumulative adverse events occurred in 30 patients (7.7%), including thromboembolic complications in 17 (4.4%), intraoperative rupture in 10 (2.6%), and others in 3 (0.8%). Statistical analyses revealed an increased intraprocedural rupture rate in the initial completely occluded aneurysms (5.6% compared with 1.0%). The incidence of cumulative adverse events was higher in patients with completely occluded aneurysms (11.1%) than in those with near-completely occluded aneurysms (5.5%). Angiography follow-up was available for 173 aneurysms. Aneurysm occlusion status at follow-up was correlated with stent placement (p ​= ​0.000, odds ratio ​= ​5.847), size (p ​= ​0.000, odds ratio ​= ​6.446 for tiny aneurysms; and p ​= ​0.001, odds ratio ​= ​5.616 for small aneurysms), and initial aneurysm occlusion status (p ​= ​0.001, odds ratio ​= ​3.436). Complete occlusion at follow-up was seen in 82.6% of the initial complete occlusion group versus 63.0% of the initial near-complete occlusion group. The incidence of complete occlusion at follow-up was higher in the initial completely occluded aneurysms with SAC (100%) than in the initial completely occluded aneurysms with non-SAC (65.2%).

Conclusions

Initial complete treatment may lead to higher complication rates and good clinical outcomes at follow-up. Stent placement may enhance progressive aneurysm occlusion. Initial complete occlusion with SAC can provide durable closure at follow-up.

Comparison of Stent-Assisted Coil Placement and Coiling-Only for the Treatment of Ruptured Intracranial Aneurysms

Background

The use of a stent during the acute post-hemorrhage period is controversial. We conducted a retrospective analysis on the clinical and angiographic outcomes of the ruptured aneurysms that were embolized with stent-assisted coiling or coiling-only.

Material/Methods

We reviewed data of 279 patients with 279 ruptured intracranial aneurysms who underwent coil embolization between July 2004 and June 2015. The baseline data on age, sex, medical history, aneurysm size, location, and Hunt and Hess grade were recorded.

Results

One hundred and thirteen aneurysms were treated with stent-assisted coiling. Adverse events occurred in similar proportions of patients in the two groups (11.5% in the stenting group and 9.0% in the coiling alone group). The incidence of permanent disabling neurologic deficit was also similar in the two groups (7.1% and 5.4% in the stenting group and coiling alone group respectively). Clinical follow-up data were available in 207 patients with a median period of 28 months. Angiographic follow-up was available in 106 aneurysms with a median period of 7.5 months. Clinical outcomes were correlated with adverse events (p=0.043, odds ratio=4.59), large aneurysms (p=0.013, odds ratio=10.24), and Hunt and Hess grade (p=0.001, odds ratio=13.51). Stent-assisted coiling for ruptured aneurysm, as compared with coiling-only, was not associated with an increased incidence of poor clinical outcome at follow-up. Aneurysm-occlusion status at follow-up were correlated with stent placement (p<0.001, odds ratio=5.85) and initial aneurysm-occlusion status (p=0.027, odds ratio=3.78).

Conclusions

Compared with coiling-only, stent-assisted coil placement may have better durability, with comparable safety for ruptured intracranial aneurysm.