Stent-assisted embolization of recurrent or residual intracranial aneurysms

Effect of Stent Porosity, Platelet Function Test Usage, and Dual Antiplatelet Therapy Duration on Clinical and Radiographic Outcomes After Stenting for Cerebral Aneurysms: A Meta-Analysis

BACKGROUND

The use of stents with various porosities for treating cerebral aneurysms requires dual antiplatelet therapy (DAPT) without clear guidelines on the utility of platelet function tests (PFTs) and the duration of DAPT. We sought to determine the effects of stent porosity, PFT usage, and DAPT duration on the radiographic and clinical outcomes after stenting of cerebral aneurysms.

METHODS

PubMed was searched on March 29, 2021 for studies of cerebral aneurysm stenting that had specified the stent type and DAPT duration. A random effects meta-analysis was used to measure the prevalence of nonprocedural thrombotic and hemorrhagic events, clinical outcomes, aneurysm occlusion, and in-stent stenosis stratified by stent porosity, PFT usage, and DAPT duration.

RESULTS

The review yielded 105 studies (89 retrospective and 16 prospective) with 117 stenting cohorts (50 high porosity, 17 intermediate porosity, and 50 low porosity). In the high-, intermediate-, and low-porosity stenting cohorts, PFT usage was 26.0%, 47.1%, and 62.0% and the mean DAPT duration was 3.51 ± 2.33, 3.97 ± 1.92, and 5.18 ± 2.27 months, respectively. The intermediate-porosity stents showed a reduced incidence of hemorrhagic events (π = 0.32%) compared with low-porosity stents (π = 1.36%; P = 0.01) and improved aneurysm occlusion (π = 6.18%) compared with high-porosity stents (π = 14.42%; P = 0.001) and low-porosity stents (π = 11.71%; P = 0.04). The prevalence of in-stent stenosis was lower for the intermediate-porosity (π = 0.57%) and high-porosity (π = 1.51%) stents than for the low-porosity stents (π = 3.30%; P < 0.05). PFT use had resulted in fewer poor clinical outcomes (π = 3.54%) compared with those without PFT use (π = 5.94%; P = 0.04). The DAPT duration had no effect on the outcomes.

CONCLUSIONS

In the present meta-analysis, which had selected for studies of cerebral aneurysm stenting that had reported the DAPT duration, intermediate-porosity stents and PFT use had resulted significantly improved outcomes. No effect of DAPT duration could be detected.

[Microsurgical and endovascular treatment of residual and recurrent cerebral aneurysms]

Cerebral aneurysms are characterized by high risk of adverse outcome due to severe intracranial hemorrhages and their consequences. Aneurysm remnants after incomplete exclusion can cause hemorrhage. Filling of these fragments immediately after surgery is usually defined as residual aneurysms. Recurrent aneurysms develop in the area of excluded aneurysm in long-term period after surgery. The authors analyze foreign and national literature data on the diagnosis and management of residual and recurrent aneurysms. Risk factors, the most common classifications, diagnostic methods and surgical treatment are presented.

Pipeline for the treatment of distal cerebral circulation aneurysms: A multicenter study focusing on periprocedural Complications

BACKGROUND AND AIM

Distal cerebral circulation aneurysms (DCCAs) remain treatment challenges for neurointervention. The off-label use of the pipeline embolization device (PED) for these aneurysms remains controversial. This study aimed to evaluate the safety and efficacy of PED for DCCAs in a multicenter cohort of patients.

METHODS

Between March 2016 and June 2021, we retrospectively analyzed the neurointerventional data on the clinical and radiological records of all patients undergoing PED treatment of DCCAs at three medical centers.

RESULTS

A total of 53 consecutive patients with 53 DCCAs were treated with PED. The mean aneurysm size was 12.3 ± 5.7 mm. In total, 75.4% (40/53) were fusiform and 24.5% (13/53) were saccular. Of these, 17.0% (9/53) were recurrent aneurysms that were previously treated with endovascular or microsurgical approaches. The technical success rate was 100%, among which 81.1% (43/53) procedures were completed with a single PED, and the rest (10/53, 18.8%) required telescoping with two devices. Angiographic follow-up data were available for 51 patients, with a median follow-up time of 12 months. At the latest follow-up, 46/51 (90.2%) aneurysms showed complete obliteration, and 4/51 (7.8%) showed reduced filling. Periprocedural complications such as hemorrhage were observed in two patients with MCA aneurysms (3.8%, 2/53), and ischemic events occurred in six patients (11.3%, 6/53). The overall mortality and morbidity rates were 7% (4/53).

CONCLUSIONS

PED is a viable option for treating DCCAs, especially for recurrent aneurysms. Coverage of bifurcation branches and perforator may increase the risk of complications.

Comparison of Pipeline Embolization Device and Traditional Endovascular Therapeutic Approaches in Distal Cerebral Circulation Aneurysms Using Propensity Score Matching Analysis

Background

Coiling and stent-assisted coiling remain the first-line treatments for distal cerebral circulation aneurysms (DCCAs). The off-label use of the pipeline embolization device (PED) for these aneurysms has been explored recently but remains controversial.

Objective

To compare traditional endovascular therapeutic approaches (coiling and stent-assisted coiling) and PED for DCCAs in a multicenter cohort of patients.

Methods

A multicenter, retrospective cohort comparison study was conducted that included consecutive patients with unruptured DCCAs treated with either traditional endovascular therapeutic approaches or PED placement at three centers between 2016 and 2020. Propensity score matching analysis was applied to adjust for baseline risk factors between the PED and TET groups. Matching was based on age, sex, aneurysm size, location, morphology, adjunctive coiling, treatment history, and preoperative mRS score.

Results

In total, 209 patients with DCCAs treated with PED or traditional endovascular therapeutic approaches were identified. Thirty-seven patients underwent PED treatment, and 172 patients underwent traditional endovascular therapeutic approaches. After propensity score matching, 37 aneurysm pairs were matched, and the baseline characteristics of the patients were balanced between the groups. The complete occlusion rate between PED and traditional endovascular therapeutic approach in both matched cohorts (91.7 vs. 92.3%, p > 0.78) was similar. The rate of periprocedural treatment-related complications in both the PED and traditional endovascular therapeutic groups was 13.5%. Univariate analysis identified average parent vessel diameter as the only predictor of complete occlusion (p = 0.038).

Conclusions

PED is a viable option for treating DCCAs by providing occlusion and complication rates similar to those of traditional endovascular therapeutic approaches. A rigid patient selection procedure and proper planning should be undertaken to reduce treatment-related complications.

Treatment of recurrent and residual aneurysms with the low-profile Acandis Acclino stent: Multi-center review of 19 patients

OBJECTIVE

To evaluate the safety and efficacy of the low-profile Acandis Acclino microstent for embolization of recurrent and residual intracranial aneurysms.

METHODS

Consecutive patients treated with the Acclino for aneurysm remnants at three German neurovascular centers were enrolled. The technical success, complications, angiographic and clinical outcome were investigated.

RESULTS

Nineteen patients (median age: 53 years) with 19 aneurysm remnants (median size: 5 mm, anterior circulation: 14) were included. Initial aneurysm treatment consisted of stand-alone coiling in 14 cases, stent-assisted coiling in 4 and clipping in 1. Acclino stent-assisted coil embolization was performed technically successfully in all patients. Morbidity occurred in one patient (5.3%) due to aneurysm perforation. At the angiographic follow-up with a median follow-up duration of 21 months (range: 5-37 months), complete occlusion was obtained in 76.9%. The retreatment rate was 7.7%.

CONCLUSIONS

Retreatment of aneurysm remnants with the Acclino microstent was associated with high aneurysm occlusion rates and acceptable morbidity. Further studies will be necessary to draw a definite conclusion.

The outcomes of recurrent wide-necked intracranial aneurysms treated with the Woven EndoBridge (WEB): A retrospective bicenter study

BACKGROUND

The Woven EndoBridge (WEB) is a device for the treatment of intracranial wide-necked bifurcation aneurysms. The safety and effectiveness of WEB for intracranial aneurysms have both been evaluated in previous trials. Our aim was to study the outcomes of recurrent intracranial aneurysms (IAs) treated with WEB.

METHODS

Clinical and radiological outcomes of patients with a wide-necked aneurysm recurrence, which was treated with WEB device, were assessed. Imaging follow-up was performed with digital subtraction angiography and/or magnetic resonance angiography. Aneurysm occlusion was determined using by the Raymond-Roy Occlusion Classification (RROC). RROC 1 and RROC 2 were considered as adequate radiological outcome.

RESULTS

Twenty-two patients with 23 recurrent IAs were treated with WEB. Of which, 17 of recurrent IAs (74%) previously treated by coiling, three (13%) by clipping and three (13%) by WEB. The most common location of the recurrent IA was the middle cerebral artery (n = 10, 43%). Endovascular treatment with WEB alone was suitable for 20 recurrent IAs (87%). Ancillary devices were also used: coils in two (9%), and a stent in one (4%). Radiological follow-up results available for all patients (range: 3-60 months; median 24 months). Adequate occlusion (RROC I and II) was achieved in 20 recurrent IAs (87%). A hemorrhagic complication occurred 2 weeks post treatment in one patient (5%).

CONCLUSIONS

WEB could be an effective treatment with low rates of complications for challenging cases of recurrent wide-necked IAs.

Retreatment With Flow Diverters and Coiling for Recurrent Aneurysms After Initial Endovascular Treatment: A Propensity Score-Matched Comparative Analysis

Background: Flow diverters and conventional coiling are established modalities for the retreatment of intracranial recurrent aneurysms after initial endovascular treatment. We aimed to compare the efficacy of these techniques. Methods: We retrospectively analyzed data for patients with recurrent aneurysms after initial endovascular treatment retreated in our center with either a pipeline embolization device (PED) or conventional coil embolization from January 2012 to July 2020. We performed 1:2 propensity score matching (PSM) using the nearest neighbor method. We controlled for: initial treatment strategy, aneurysm size, neck diameter, symptom presentation, history of aneurysm rupture, age, sex, fusiform-dissecting aneurysm, bifurcation aneurysm, and aneurysm location. The clinical and morphological factors of all patients at initial treatment and the angiographic and clinical results at the second treatment were collected and compared between the propensity-matched pairs. Results: A total of 105 intracranial aneurysms were identified; 18 patients (17.1%) were treated with a PED, and 87 (82.9%) were treated via conventional coil embolization. PSM resulted in 12 matched pairs (12 patients in the PED group and 24 in the coiling group). There was no significant difference of ischemic and hemorrhagic complications between the groups, the obliteration rate of branches covered by stent, or modified Rankin Scale scores at the last clinical follow-up. Importantly, the retreatment strategy in the PED group provided significantly different results vs. the coiling group (P < 0.001), with a lower recurrence rate (0.0 vs. 29.2%, respectively; P = 0.037). However, the procedural failure rate and the parent artery stenosis were more frequently in PED group compared with coiling group (both were 16.7 vs. 0.0%; P = 0.040). Conclusions: Endovascular retreatment for recurrent aneurysms after initial endovascular treatment might be safe and effective. Flow diverters might be associated with reduced risk of recanalization and an increased risk of procedural failure and mild parent artery stenosis.

Management of Recurrent Aneurysms after Endovascular Coiling: A Fujita Experience

Introduction:

Microsurgical clipping and Endovascular coiling (EC) are both effective alternatives in the management of intracranial aneurysms. EC has been shown to be associated with the risk of recurrent aneurysm (RA) growth. Considering the minimally invasive nature of this procedure, the management of intracranial aneurysms has been skewed toward EC, especially in the developed world. In this scenario, there has been an upsurge of RAs after EC. Since the optimal management of these RAs has not been defined, they pose a unique challenge to the treating surgeons.

Aims and Objectives:

The aim of this study is to elucidate the optimal management of RAs after EC.

Materials and Methods:

Medical records of all patients who underwent surgery for RAs were reviewed from the period January 2014 to March 2019. The demographic and angiographic patterns of the patients and operative techniques and complications were studied. The outcome was dichotomized into good and bad depending on the Glasgow outcome scale (GOS).

Results:

There were four cases of RAs operated in our institution between the above-mentioned period. There were varied differences between the initial coiling and time to recurrences. All four patients were operated under neuromonitoring. Three underwent clipping and one patient underwent clipping with bypass. All four patients had good outcome with a GOS of 5/5.

Conclusion:

Operations for RAs constitute many technical challenges and require a lot of expertise. Such surgeries are recommended in high-volume centers, with sufficient experience in both clipping and cerebral bypass.

Clipping of Recurrent Cerebral Aneurysms After Coil Embolization

BACKGROUND AND AIMS

To assess the technical points of surgical clipping for recurrent aneurysms after coiling, we examine a consecutive series of 14 patients who underwent re-treatment.

MATERIALS AND METHODS

From 2009 to 2016, 27 recurrent aneurysms after coiling were re-treated with endovascular treatment or surgical clipping. Of these, 14 were re-treated surgically. In cases where the remnant neck was sufficiently large, neck clipping was chosen. Where the remnant neck was too small and the border between the thrombosed and non-thrombosed portion was distinct, partial clipping was chosen. Surgical clipping was attempted without removing the coils when technically feasible.

RESULTS

Among the 14 cases, neck clipping was performed in 11, partial clipping in 2, and trapping with bypass in 1 case. Clipping without removal of coils was accomplished in all cases. No neurological deterioration occurred after surgical clipping in any case.

CONCLUSION

Clipping of recurrent aneurysms after coiling can compensate for the failure of initial endovascular therapy. For clipping without removal of coils, precise evaluation of the remnant neck is required. Bypass surgery is key to treatment in the case of aneurysm trapping.

A Novel Flow Diverter (Tubridge) for the Treatment of Recurrent Aneurysms: A Single-Center Experience

Objective

The Tubridge flow diverter (FD) is a novel device aimed at reconstructing the parent artery and occluding complex aneurysms. Retreatment of recurrent aneurysms using the FD is challenging. We report our initial experience in the repair of aneurysm recurrence with the FD.

Materials and Methods

A database was reviewed prospectively, and 8 patients with 8 recurrent aneurysms (mean size, 16.7 mm) were identified. Four aneurysms had previously ruptured. The previous aneurysm treatment consisted of coiling in 1 aneurysm and single-stent-assisted coiling in 7 aneurysms. The procedural complications and clinical and angiographic outcomes were analyzed.

Results

Six aneurysms were treated by using a single Tubridge FD alone, while the remaining 2 were treated with FD + coiling. The immediate results of the 8 aneurysms were that they all showed incomplete occlusion. Neither major ischemic nor hemorrhagic complications occurred; however, 1 patient experienced a vasospasm. Follow-up angiographies were available for 7 aneurysms; the mean follow-up was 16.9 months (7–36 months). Five aneurysms were completely occluded, whereas 2 had a residual neck. Severe asymptomatic stenosis of 1 parent artery of a vertebral artery dissecting aneurysm was found. All visible branches covered by the FD were patent. All patients were clinically assessed as having attained a favorable outcome (modified Rankin Scale score ≤ 2) at discharge and follow-up.

Conclusion

In selected patients, the Tubridge FD can provide a safe and efficient option for the retreatment of recurrent aneurysms. Nevertheless, attention should be paid to several technical points.

A Single Center Experience with Coil Embolization for Cerebral Aneurysms Greater than 10 mm in the Internal Carotid Artery

We investigated endovascular treatment for 10 mm or larger aneurysms in the internal carotid artery (IC), including the cavernous portion, the paraclinoid portion, and the posterior communication artery (PC). Between 2011 and 2014 at our hospital, there were 35 cases of aneurysms that were 10 mm or larger in the carotid artery. We analyzed these 35 cases retrospectively based on the size and location of the aneurysms, method of treatment, number of coils implanted, use of a stent, complications, rupture after treatment, ophthalmologic symptoms, and need for re-treatment. There was no bleeding after treatment. Of the 35 cases, four cases (11%) had permanent complications. Re-treatment was indicated in 11 cases (31%), including eight cases localized in the paraclinoid portion, two cases in the IC-PC, and one case in the cavernous portion. Among these re-treatment cases, two cases required a third treatment. Of the 16 cases with paraclinoid aneurysms, half required re-treatment. Of the 12 cases with ophthalmologic symptoms prior to treatment, 9 (75%) improved or had no change and 3 (25%) became worse. There were no complications in the 13 re-treatment procedures. Re-treatment is not uncommon, and a scheduled follow-up is needed. Coil embolization has been one of the main options for aneurysms that are 10 mm or larger in the IC. In the future, these large aneurysms will be treated with a flow diverter stent (FD).

Intracranial post-embolization residual or recurrent aneurysms: Current management using surgical clipping

Post-embolization residual or recurrent aneurysms (PERRAs) are not rare in patients with intracranial aneurysms treated by embolization. Their occurrence is mainly associated with an increased amount of interventional therapy. Repeated interventional embolization can be applied in some patients with PERRAs, whereas surgical clipping is preferred in other cases that are not suitable for repeated interventional embolization due to the difficulties inherent to this operation. The surgical clipping of PERRAs is very complicated and difficult to perform, and relevant reports are rare. This study offers a review of PERRA treatment using surgical clipping. Retrospective studies have shown that PERRAs are common aneurysms of the anterior and posterior communicating arteries. According to the recurrent characteristics of PERRAs, it is reasonable to categorize PERRAs into three types: type I-coils are compressed, and no embolic material fills the neck of the aneurysm; type II-coils are migrated, and very few coils fill the neck of the aneurysm or the parent artery; and type III-coils are migrated, and multiple coils fill the neck of the aneurysm or the parent artery. Direct clipping can be applied to types I and II PERRAs, whereas trapping, wrapping, or auxiliary revascularization is required in type III PERRAs. Most coils do not require removal unless they interfere with clipping. However, it is necessary to avoid damaging the surrounding adhesive tissue during coil removal. Satisfactory therapeutic outcomes can be achieved by selecting appropriate PERRA cases in which to perform surgical clipping.

Clipping of previously coiled cerebral aneurysms: efficacy, safety, and predictors in a cohort of 111 patients

OBJECTIVE With the increasing number of aneurysms treated with endovascular coiling, more recurrences are being encountered. The aim of this study was to evaluate the efficacy and safety of microsurgical clipping in the treatment of recurrent, previously coiled cerebral aneurysms and to identify risk factors that can affect the outcomes of this procedure. METHODS One hundred eleven patients with recurrent aneurysms whose lesions were managed by surgical clipping between January 2002 and October 2014 were identified. The rates of aneurysm occlusion, retreatment, complications, and good clinical outcome were retrospectively determined. Univariate and multivariate logistic regressions were performed to identify factors associated with these outcomes. RESULTS The mean patient age was 50.5 years, the mean aneurysm size was 7 mm, and 97.3% of aneurysms were located in the anterior circulation. The mean follow-up was 22 months. Complete aneurysm occlusion, as assessed by intraoperative angiography, was achieved in 97.3% of aneurysms (108 of 111 patients). Among patients, 1.8% (2 of 111 patients) had a recurrence after clipping. Retreatment was required in 4.5% of patients (5 of 111) after clipping. Major complications were observed in 8% of patients and mortality in 2.7%. Ninety percent of patients had a good clinical outcome. Aneurysm size (OR 1.4, 95% CI 1.08-1.7; p = 0.009) and location in the posterior circulation were significantly associated with higher complications. All 3 patients who had coil extraction experienced a postoperative stroke. Aneurysm size (OR 1.2, 95% CI 1.02-1.45; p = 0.025) and higher number of interventions prior to clipping (OR 5.3, 95% CI 1.3-21.4; p = 0.019) were significant predictors of poor outcome. An aneurysm size > 7 mm was a significant predictor of incomplete obliteration and retreatment (p = 0.018). CONCLUSIONS Surgical clipping is safe and effective in treating recurrent, previously coiled cerebral aneurysms. Aneurysm size, location, and number of previous coiling procedures are important factors to consider in the management of these aneurysms.

Retreatment of Recurrent Internal Carotid-Posterior Communicating Artery Aneurysm after Coil Embolization

Internal carotid-posterior communicating artery (IC-PC) aneurysms account for more than 20% of all intracranial aneurysms. As a result of the increase in coiling, there has also been an increase in recurrent IC-PC aneurysms after coiling. We present our experience of 10 recurrent IC-PC aneurysms after coiling that were retreated using surgical or endovascular techniques in order to discuss the choice of treatment and the points of clipping without removal of coils. From 2007 to 2014, 10 recurrent IC-PC aneurysms after coiling were retreated. When the previous frames covered the aneurysms all around or almost around except a part of the neck, coiling was chosen. In other cases, clipping was chosen. Clipping was attempted without removal of coils when it was technically feasible. Among the 10 IC-PC aneurysms retreated, 3 were retreated with coiling and 7 were retreated with clipping. In all three cases retreated with coiling, almost complete occlusion was accomplished. In the seven cases retreated with clipping, coil extrusion was observed during surgery in six cases. In most of them, it was necessary to dissect strong adhesions around the coiled aneurysms and to utilize temporary occlusion of the internal carotid artery. In all seven cases, neck clipping was accomplished without the removal of coils. There were no neurological complications in any cases. The management of recurrent lesions of embolized IC-PC aneurysms requires appropriate choice of treatment using both coiling and clipping. Clipping, especially without the removal of coils, plays an important role in safe treatment.

The Use of the Pipeline Embolization Device in the Management of Recurrent Previously Coiled Cerebral Aneurysms

BACKGROUND:

The biggest downside of cerebral aneurysm coiling is the high rates of recurrence and retreatments. With the increasing number of aneurysm recurrences after failed coiling procedures, the best retreatment strategy remains unknown.

OBJECTIVE:

To assess the efficacy and safety of the Pipeline Embolization Device (PED) in the treatment of recurrent previously coiled aneurysms.

METHODS:

Thirty-three patients who underwent treatment with the PED of a recurrent previously coiled aneurysm were retrospectively identified. Efficacy was assessed in terms of angiographic occlusion at the latest cerebral angiogram, recurrence and retreatment rates after PED placement, and clinical outcome at the latest follow-up. Safety was assessed by looking at the complications, morbidity, and mortality after PED treatment.

RESULTS:

The mean patient age was 53 years. The mean percent recurrence from coiling to PED placement was 34%. The mean time from coiling to PED placement was 40 months. PED treatment resulted in complete aneurysm occlusion in 76.7% of patients and near-complete aneurysm occlusion (≥90%) in 10%, for a total rate of complete and near-complete aneurysm occlusion of 86.7%. All patients, including those with incomplete aneurysm occlusion, had a significant reduction in aneurysm size. Two aneurysms required another retreatment after PED placement (6.2%). Ninety-seven percent of patients had a good clinical outcome. Complications were observed in 1 patient (3%), who suffered an intracerebral hemorrhage. There were no mortalities.

CONCLUSION:

The use of the PED in the management of recurrent, previously coiled aneurysms is safe and effective in achieving aneurysm occlusion.