Safety and efficacy of Surpass Evolve Flow diverter for intracranial aneurysms: A study of 116 patients

BACKGROUND AND PURPOSE

Flow diverter embolization is a recognized method for treating intracranial aneurysms. This study evaluates the safety and efficacy of the Surpass Evolve flow diverter in treating intracranial aneurysm.

MATERIAL AND METHODS

From May 2019 to June 2022, our center prospectively enrolled patients presenting with both ruptured and unruptured intracranial aneurysms. We assessed aneurysm occlusion, along with the occurrence of ischemic and hemorrhagic complications, and mortality at 6-months. The 3-month occlusion rate was determined using MR angiography, while the 6-month occlusion rate employed the O'Kelly-Marotta (OKM) grading scale on DSA.

RESULTS

A total of 116 patients with 120 aneurysms received treatment with the Surpass Evolve device. The average aneurysm size was 6.6 mm (range: 2-30 mm). All patients were administered two loading doses of ticagrelor (180 mg) one day before the procedure and 2 h pre-embolization. A procedural complication occurred in one case, involving wire-related perforation of an M3 branch distant from the giant aneurysm; however, this evolved favorably. There were no reported deaths linked to the treatment. Permanent neurological deficits were observed in 3 (2.5%) patients, primarily due to early in-stent thrombosis. MR angiography results at 3 months indicated complete occlusion for 87 out of 115 (75.6%) monitored aneurysms. The 6-month DSA showed neck remnant or complete occlusion (OKM grade C or D) in 86 out of the 107 (80.4%) patients who underwent follow-up.

CONCLUSION

The Surpass Evolve stands out as a reliable and effective flow diverter for the management of intracranial aneurysms.

Safety and efficacy analysis of the off-label use of pipeline embolization devices for intracranial aneurysms: a propensity score matching study

Background and objective

The safety and efficacy of on-label use of pipeline embolization devices (PEDs) are well established; however, there is much controversy over their off-label use. This study aimed to investigate the safety and efficacy of the off-label use of PEDs for treating intracranial aneurysms.

Methods

This single-center study retrospectively included patients with digital subtraction angiography, computed tomographic angiography, or magnetic resonance angiography confirmed intracranial aneurysms treated with PEDs who were admitted to our institution between 1 January 2018 and 1 July 2022. Patients were divided into on- and off-label groups according to the Food and Drug Administration criteria published in 2021. Propensity score matching (PSM) was used to balance disparities in baseline information between the two groups. Safety outcomes included postoperative mortality and complication rates, whereas effectiveness outcomes included aneurysm occlusion rate (O'Kelly-Marotta grading system C + D grades), retreatment rate within 12 months, and postoperative functional score [modified Rankin scale (mRS) score]. The study was approved by the Ethics Committee of Scientific Research and Clinical Trial of the First Affiliated Hospital of Zhengzhou University (Ethics number: KY 2018-098-02). All patients provided informed consent.

Results

A total of 242 patients with 261 aneurysms (160 on-label and 101 off-label aneurysms) were included in this study. PSM yielded 81 pairs of patients matched for baseline information. Postoperative hemorrhagic, ischemic, and procedure-related complication rates did not reach statistical significance. In addition, no statistically significant differences in the aneurysm occlusion rate, retreatment rate within 12 months, postoperative functional score (mRS score), or mRS score deterioration rate were observed between the two groups. A higher incidence of in-stent stenosis was observed in the off-label (4.9% vs. 21%, p = 0.002) group than in the on-label group; however, all patients were asymptomatic.

Conclusion

Compared with on-label use, off-label use of PEDs for treating intracranial aneurysms did not increase the risk of complications, and the occlusion rates were comparable. Therefore, decisions regarding clinical management should not rely solely on on- or off-label indications.

Early Outcomes of the Pipeline Vantage Flow Diverter : A Multicentre Study

PURPOSE

The recently introduced Pipeline Vantage Embolization Device with Shield Technology is the fourth generation of Pipeline flow diverter devices. Due to the relatively high rate of intraprocedural technical complications, modifications were subsequently made to the device after a limited release of the device in 2020. This study aimed to evaluate the safety and efficacy of the modified version of this device.

METHODS

This was a multicentre retrospective series. The primary efficacy endpoint was aneurysm occlusion in the absence of retreatment. The primary safety endpoint was any neurological morbidity or death. Ruptured and unruptured aneurysms were included in the study.

RESULTS

A total of 52 procedures were performed for 60 target aneurysms. Treatment was performed on 5 patients with ruptured aneurysms. The technical success rate was 98%. The mean clinical follow-up time was 5.5 months. In patients presenting with unruptured aneurysms there were no deaths, 3 (6.4%) major complications and 7 (13%) minor complications. In the five patients presenting with subarachnoid haemorrhage there were 2 (40%) major complications with 1 (20%) of these resulting in death, and 1 (20%) minor complication. Of the patients 29 (56%) had undergone 6‑monthly postprocedural angiographic imaging with a mean time of 6.6 months demonstrating that 83% of patients had achieved adequate occlusion (RROC1/2) of the aneurysm.

CONCLUSIONS

In this non-industry-sponsored study, the occlusion rates and safety outcomes were similar to those seen in previously published studies with flow diverter devices and earlier generation Pipeline devices. Modifications to the device appear to have improved ease of deployment.

Long-term outcomes and dynamic changes of in-stent stenosis after Pipeline embolization device treatment of intracranial aneurysms

BACKGROUND

Flow diverters have revolutionized the treatment of intracranial aneurysms. However, the delayed complications associated with flow diverter use are unknown.

OBJECTIVE

To evaluate the incidence, severity, clinical outcomes, risk factors, and dynamic changes associated with in-stent stenosis (ISS) after treatment with a Pipeline embolization device (PED).

METHODS

Patients who underwent PED treatment between 2015 and 2020 were enrolled. The angiographic, clinical, and follow-up data of 459 patients were independently reviewed by four neuroradiologists to identify ISS. Binary logistic regression was conducted to determine ISS risk factors, and an ISS-time curve was established to demonstrate dynamic changes in ISS after PED implantation.

RESULTS

Of the 459 treated patients, 69 (15.0%) developed ISS. At follow-up, nine patients (2.0%) with ISS demonstrated reversal, while 18 (3.9%) developed parental artery occlusion. A total of 380 patients (82.8%) achieved complete aneurysm occlusion (O'Kelly-Marotta grade D). Patients with posterior-circulation aneurysm (OR=2.895, 95% CI (1.732 to 4.838; P<0.001) or balloon angioplasty (OR=1.992, 95% CI 1.162 to 3.414; P=0.037) were more likely to develop ISS. Patients aged >54 years (OR=0.464, 95% CI 0.274 to 0.785; P=0.006) or with a body mass index of >28 kg/m2 (OR=0.427, 95% CI 0.184 to 0.991; P=0.026) had a lower ISS risk. Intimal hyperplasia initiated by PED placement peaked within 1 year after the procedure, rarely progressed after 12 months, and tended to reverse within 24 months.

CONCLUSIONS

ISS is a common, benign, and self-limiting complication of PED implantation in the Chinese population.

Parent artery occlusion after pipeline embolization device implantation of intracranial saccular and fusiform aneurysms

BACKGROUND

Studies reporting parent artery occlusion (PAO) after pipeline embolization device (PED) implantation are limited. The aim of this study was to investigate the incidence rate and risk factors of PAO after PED implantation.

METHODS

In this retrospective study, we enrolled consecutive patients with intracranial saccular and fusiform aneurysms treated with PED implantation at our institution. Multivariate logistic regression analysis was subsequently performed to determine the risk factors for PAO.

RESULTS

A total of 588 saccular and fusiform aneurysms were finally enrolled in the study. PAO was found in 14 (2.38%) aneurysms. The aneurysm complete occlusion rate was 79.6%. Compared with the non-PAO group, aneurysms in the PAO group were larger in size (20.08 vs 9.61 mm; p<0.001), had a greater neck diameter (9.92 vs 6.15 mm; p=0.001), and had higher frequencies of adjunctive coils (64.3% vs 35.7%; p=0.028). In the multivariate logistic analysis, aneurysm size (OR 1.12, 95% CI 1.02 to 1.24; p=0.016) and the presence of poor wall apposition after balloon angioplasty (OR 7.74, 95% CI 1.28 to 46.82; p=0.026) were associated with PAO occurrence after adjusting for confounding factors.

CONCLUSIONS

In this study, the incidence rate of PAO following PED implantation was 2.38% in intracranial saccular and fusiform aneurysms. Aneurysm size and residual presence of poor wall apposition after balloon angioplasty were risk factors for PAO. Further research is required to better understand the mechanisms of PAO.

Comparative outcomes of the treatment of unruptured paraophthalmic aneurysms in the era of flow diversion

BACKGROUND

Paraophthalmic aneurysms present a challenge to surgeons and their ideal management remains up for debate. We studied recent outcomes of these lesions in a single center.

METHODS

A retrospective chart review of all patients undergoing treatment for paraophthalmic aneurysms from 2017-2019 was performed. Factors including patient demographics, aneurysm characteristics, treatment modality, radiographic treatment outcome, clinical outcome, and length of stay were collected, and bivariate analysis was performed.

RESULTS

In total 84.5% (82/97) of aneurysms were treated endovascularly and 15.5% (15/97) surgically. In the surgery cohort, there were three transient perioperative complications (20%) and one minor postoperative complication (6.7%). Complete aneurysm occlusion or near complete (<2mm residual) was achieved in 100% (15/15). All but one patient had mRS ≤1 at the last follow-up. In the endovascular group, 78.1% (64/82) underwent flow diversion alone. Endovascular treatment was associated with a 4.9% (4/82) rate of periprocedural complications: 3 transient events, and 1 death, and a 3.7% (3/82) rate of delayed complications: 2 transient vision changes, and one death. Rate of total occlusion was 87.8% (72/82). 76 patients (92.7%) had mRS ≤1 at the last follow-up. Length of stay was significantly shorter in the endovascular group (3.4 days vs. 7.0 days) [p < 0.001].

CONCLUSIONS

This series demonstrates similar safety to previously reported series as well as the efficacy of both surgical clipping and endovascular embolization of paraophthalmic aneurysms. Rate of complications and treatment efficacy were similar in both groups although this represents a single institution series not generalizable to all centers.

The incidence and predictors of in-stent stenosis after pipeline flow-diverter stenting for intracranial aneurysm treatment

Background and purpose

Data on in-stent stenosis (ISS) following the flow diverter (FD) implantation method are scarce and inconsistent. In the present study, we sought to determine the incidence of ISS and identify the factors that predict its severity via the use of ordinal logistic regression.

Methods

A retrospective review of our center's electronic database was conducted to identify all patients with intracranial aneurysms (IAs) who received pipeline embolization device (PED) implantation between 2016 and 2020. Patient demographics, aneurysm characteristics, procedural information, and clinical and angiographic outcomes were reviewed. ISS was quantitatively assessed on angiographic follow-ups and graded as mild (<25%), moderate (25-50%), or severe (>50%). Ordinal logistic regression was conducted to determine the predictors of stenosis severity.

Results

A total of 240 patients with 252 aneurysms treated in 252 procedures were enrolled in this study. ISS has been detected in 135 (53.6%) lesions, with a mean follow-up time of 6.53 ± 3.26 months. The ISS was mild in 66 (48.9%) cases, moderate in 52 (38.5%) cases, and severe in 17 (12.6%) cases. All patients were asymptomatic, except for two of them with severe stenosis who presented with symptoms of acute cerebral thrombosis. Ordinal logistic regression identified that younger age and a longer procedure duration were independent predictors of a higher likelihood of ISS.

Conclusion

ISS is a common angiographic finding after PED implantation for IAs and is presented as a largely benign course through long-term follow-up. Patients who were younger in age and had a longer procedure duration were found to be at a greater risk of developing ISS.

Treatment of fusiform aneurysms with a pipeline embolization device: a multicenter cohort study

BACKGROUND

Intracranial fusiform aneurysms are less common than saccular aneurysms, but are associated with higher mortality and morbidity. We conducted this study to determine the safety and efficacy of the pipeline embolization device (PED) to treat intracranial fusiform aneurysms.

METHODS

This was a multicenter, retrospective, and observational study. Data for this study came from the PLUS study conducted from 2014 to 2019 across 14 centers in China. Univariate and multivariable logistic regression analyses were performed to evaluate predictors of the occlusion rate and complication.

RESULTS

A total of 1171 consecutive patients with 1322 intracranial aneurysms participated in this study. Among the participants, 104 patients with 109 fusiform aneurysms were eligible for this analysis (mean age 49 years, 36.5% women, aneurysm mean size 14.7 mm, 55% in the posterior circulation, and 6% in the basilar artery). Mean follow-up time was 9.0 months (range 3-36 months). The last DSA angiographic follow-up was available for 85 patients, and 58 aneurysms (68.2%) were completely occluded. The overall complication rate and mortality were 17.3% and 2.8%, respectively. Multivariate analysis demonstrated that age (OR=1.007, p=0.037) and cerebral atherosclerosis (OR=1.441, p=0.002) were associated with incomplete occlusion of fusiform aneurysms after PED treatment.

CONCLUSION

PEDs may be an effective treatment for intracranial fusiform aneurysms, with a favorable occlusion rate. However, because these treatments have a relatively high rate of complications, PED treatment for fusiform aneurysms should be carefully and strictly controlled. Our analysis showed that PEDs with adjunctive coiling did not significantly improve the occlusion rate of fusiform aneurysms.

Technical Nuances and Outcomes of Telescoping Pipeline Flow Diverters: A Multicenter Study

BACKGROUND

"Telescoping" multiple overlapping Pipeline Embolization Devices (PEDs; Medtronic) has increased their utility by allowing for more impermeable coverage and providing the ability to off-set landing zone sites and extend treatment constructs.

OBJECTIVE

To consider the technical nuances and challenges of telescoping PEDs for the treatment of intracranial aneurysms.

METHODS

Databases from 3 U.S. academic neurovascular centers were retrospectively queried to identify patients with intracranial aneurysms treated with multiple PED constructs. Data on patient and aneurysm characteristics, as well as outcomes including Raymond-Roy occlusion classification, modified Rankin Scale score, and complications, were gathered.

RESULTS

Forty-six patients had 48 intracranial aneurysms treated, including 16 (33%) in whom placement of telescoping PEDs was planned. Fourteen (30%) patients presented with a ruptured aneurysm. Twenty-one aneurysms (44%) were treated with proximal extension, 13 (27%) with distal extension, and 14 (29%) with PED placement inside one another. Thirty (70%) patients had complete aneurysm occlusion at follow-up. Two (4%) patients had to be retreated. Three patients with unruptured and 1 with ruptured aneurysm had a permanent intraprocedural complication. We present descriptive cases illustrating PEDs that were placed inside one another, proximally, distally, and to improve wall apposition because of vessel tortuosity.

CONCLUSION

Our data indicate a higher than expected complication rate that is likely because of the technical complexity of these cases. The case illustrations presented demonstrate the indications and challenging aspects of telescoping PEDs.

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.

Factors associated with in-stent stenosis after cerebral aneurysm embolization using a Pipeline embolization device

BACKGROUND

Flow-diverting (FD) stents, with or without coiling, are a mainstay in endovascular treatment of intracranial aneurysms (IAs). One observed complication from flow diverter stent (FDS) insertion has been in-stent stenosis. Though previously studied in the short-term period, the long-term history of this complication has yet to be described.

METHODS

We performed a retrospective cohort study of consecutive IAs treated with Pipeline Embolization Device (PED), with or without coiling, at our centre between September 2014 and December 2018 that had at least one digital subtraction angiogram (DSA) during follow-up. In-stent stenosis was measured from DSA images, and associated patient and procedural characteristics were analysed.

RESULTS

94 patients treated with PED for IA were identified. On initial DSA during follow-up, 52 patients (55.3%) had in-stent stenosis within the PED. Of these 52 patients, 17 had a second DSA during follow-up. In this 2nd DSA, improvement and/or stable in-stent stenosis was seen 16 patients (94.1%). One patient in this group had worsening in-stent stenosis had a vertebrobasilar junction FD stent. Of the patients without in-stent stenosis on initial DSA, 15 had a second DSA during follow-up. Only one of these patients (6.7%) had new appearance of in-stent stenosis (measuring 5%). Multivariate analysis found statin use to be predictive of in-stent stenosis (p = 0.020, Odds ratio = 0.279 and 95% confidence interval = 0.095-0.821).

CONCLUSIONS

In-stent stenosis after FDS placement was seen in 53.2% of cases, which had between 1-50% of stenosis. 82.4% had resolution/improvement of their stenosis. Statin use was protective of in-stent stenosis.

In-Stent Stenosis After Pipeline Embolization Device in Intracranial Aneurysms: Incidence, Predictors, and Clinical Outcomes

BACKGROUND

In-stent stenosis (ISS) is a delayed complication that can occur after pipeline embolization device use when treating intracranial aneurysms (IAs).

OBJECTIVE

To assess the incidence, predictors, and outcomes of ISS.

METHODS

This was a retrospective, multicenter, observational study. All patient data were collected from a PLUS registry study. We collected data from patients with IA who completed digital subtraction angiography at follow-up and divided patients into "non-ISS," "mild ISS," or "severe ISS" groups. Multivariate logistic regression analysis was conducted to determine predictors of ISS.

RESULTS

A total of 1171 consecutive patients with 1322 IAs participated in this study. Angiographic follow-up was available for 662 patients with 728 IAs, and the mean follow-up time was 9 months. ISS was detected in 73 cases (10.03%), including 61 mild ISS cases and 12 severe ISS cases. Univariate and multivariable analysis demonstrated that current smoking history (mild ISS: OR 2.15, 95% CI 1.122-4.118, P = .021; severe ISS: OR 5.858, 95% CI 1.186-28.93, P = .030) and cerebral atherosclerosis (mild ISS: OR 5.694, 95% CI 3.193-10.15, P = .001; severe ISS: OR 6.103, 95% CI 1.384-26.91, P = .017) were independent predictors of ISS. Compared with the other groups, the severe ISS group had higher rate of ischemic stroke (33.3%).

CONCLUSION

ISS occurs in approximately 10.03% of cases at a mean follow-up of 9 months. Statistically, current smoking history and cerebral atherosclerosis are the main predictors of ISS. Severe ISS may be associated with higher risk of neurological ischemic events in patients with IA after pipeline embolization device implantation.

Machine learning to predict in-stent stenosis after Pipeline embolization device placement

Background

The Pipeline embolization device (PED) is a flow diverter used to treat intracranial aneurysms. In-stent stenosis (ISS) is a common complication of PED placement that can affect long-term outcome. This study aimed to establish a feasible, effective, and reliable model to predict ISS using machine learning methodology.

Methods

We retrospectively examined clinical, laboratory, and imaging data obtained from 435 patients with intracranial aneurysms who underwent PED placement in our center. Aneurysm morphological measurements were manually measured on pre- and posttreatment imaging studies by three experienced neurointerventionalists. ISS was defined as stenosis rate >50% within the PED. We compared the performance of five machine learning algorithms (elastic net (ENT), support vector machine, Xgboost, Gaussian Naïve Bayes, and random forest) in predicting ISS. Shapley additive explanation was applied to provide an explanation for the predictions.

Results

A total of 69 ISS cases (15.2%) were identified. Six predictors of ISS (age, obesity, balloon angioplasty, internal carotid artery location, neck ratio, and coefficient of variation of red cell volume distribution width) were identified. The ENT model had the best predictive performance with a mean area under the receiver operating characteristic curve of 0.709 (95% confidence interval [CI], 0.697–0.721), mean sensitivity of 77.9% (95% CI, 75.1–80.6%), and mean specificity of 63.4% (95% CI, 60.8–65.9%) in Monte Carlo cross-validation. Shapley additive explanation analysis showed that internal carotid artery location was the most important predictor of ISS.

Conclusion

Our machine learning model can predict ISS after PED placement for treatment of intracranial aneurysms and has the potential to improve patient outcomes.

Pipeline Embolization Device for the Treatment of Ruptured Intracerebral Aneurysms: A Multicenter Retrospective Study

Background and Purpose: The utilization of flow diversion for ruptured intracerebral aneurysms (IAs) is still limited. We aimed to demonstrate our multicenter experience using the pipeline embolization device (PED) for ruptured IAs that were difficult to treat by clipping and coiling.

Methods: Thirty-eight patients with ruptured IAs who underwent PED treatment from 2015 to 2020 were retrospectively reviewed. Factors associated with procedure-related stroke (ischemic and hemorrhagic) and clinical and angiography outcomes were analyzed.

Results: There were 14 (36.8%) saccular IAs, 12 (31.6%) blister-like IAs, and 12 (31.6%) dissecting IAs. Perforator involvement was noted in 10 (26.3%) IAs. Early PED placement ( ≤ 15 days) and adjunctive coiling treatment were performed in 27 (71.1%) and 22 (57.9%) cases, respectively. The overall rate of stroke-related complications was 31.6% (12/38) (including rates of 10.5% for procedure-related hemorrhagic complications and 15.8% for procedure-related infarction). The mortality rate was 13.2% (5/38), and 84.2% of patients (32/38) had favorable outcomes. Thirty-two (84.2%) patients underwent follow-up angiographic evaluations; of these, 84.4% (27 patients) had complete occlusion and 15.6% had incomplete obliteration. Multivariate analysis revealed that early PED placement was not associated with a high risk of procedure-related stroke or an unfavorable outcome. Adjunctive coiling exhibited an association with procedure-related stroke (p = 0.073). Procedure-related hemorrhagic complications were significantly associated with an unfavorable outcome (p = 0.003). Immediate contrast stasis in the venous phase was associated with complete occlusion during follow-up (p = 0.050).

Conclusion: The PED is a feasible and effective treatment to prevent rebleeding and achieve aneurysm occlusion, but it is associated with a substantial risk of periprocedural hemorrhage and ischemic complications in acute ruptured IAs. Therefore, the PED should be used selectively for acutely ruptured IAs. Additionally, adjunctive coiling might increase procedure-related stroke; however, it may reduce aneurysm rebleeding in acutely ruptured IAs. Patients with immediate contrast stasis in the venous phase were more likely to achieve total occlusion. A prospective study with a larger sample size should be performed to verify our results.

Using angiographic parametric imaging-derived radiomics features to predict complications and embolization outcomes of intracranial aneurysms treated by pipeline embolization devices

BACKGROUND

Pipeline embolization devices (PEDs) have gained widespread popularity in the treatment of intracranial aneurysms (IAs). However, precise predictors of treatment outcomes are still lacking. This study aimed to use angiographic parametric imaging (API)-derived radiomics features to explore whether biomarkers extracted from immediate postprocedural digital subtraction angiography (DSA) were associated with complications and embolization outcomes of IAs treated with PED without adjunctive coils.

METHODS

Radiomic features were extracted from postprocedural DSA by API, and radiomics feature selection and radiomics score calculation were performed by the least absolute shrinkage and selection operator (LASSO) logistic regression. Angiographic findings and clinical characteristics were screened using stepwise multivariable logistic regression analysis to identify significant variables for predicting the complication endpoint. Radiomics feature selection and radiomics risk score (RadRS) calculations were performed by LASSO Cox regression. Univariate and multivariate Cox regression analyses were used to identify significant predictors for the occlusion endpoint.

RESULTS

We screened 281 observations for complications and 235 observations for embolization outcomes from IAs treated in our center using PED between June 2015 and July 2020. Multivariate regression analysis showed association of the radiomics score (p<0.01) and hypertension (p=0.04) with complications. RadRS (p<0.01), symptoms (p<0.01), and age (p=0.03) were predictors of embolization outcomes. Kaplan-Meier analysis revealed that symptomatic patients (p<0.01) and those with off-label IAs (p=0.03) had shorter intervals to complete occlusion.

CONCLUSIONS

Biomarkers extracted from immediate postprocedural DSA by API could be potential indicators for assessing treatment outcomes of IAs treated by PED without adjunctive coils.

P2Y12 inhibitors for the neurointerventionalist

The use of antiplatelets is widespread in clinical practice. However, for neurointerventional procedures, protocols for antiplatelet use are scarce and practice varies between individuals and institutions. This is further complicated by the quantity of antiplatelet agents which differ in route of administration, dosage, onset of action, efficacy and ischemic and hemorrhagic complications. Clarifying the individual characteristics for each antiplatelet agent, and their associated risks, will increasingly become relevant as the practice of mechanical thrombectomy, stenting, coiling and flow diversion procedures grows. The aim of this review is to summarize the existing literature for the use of P2Y12 inhibitors in neurointerventional procedures, examine the quality of the evidence, and highlight areas in need of further research.

Optical coherence tomography for elucidation of flow-diversion phenomena: The concept of endothelized mural thrombus behind reversible in-stent stenosis in flow-diverters

PURPOSE

Flow-diverters have revolutionized the endovascular treatment of intracranial aneurysms, offering a durable solution to aneurysms with high recurrence rates after conventional stent-assisted coiling. Events that occur after treatment with flow-diversion, such as in-stent stenosis (ISS) are not well understood and require further assessment. After assessing an animal model with Optical Coherence Tomography (OCT), we propose a concept that could explain the mechanism causing reversible ISS after treatment of intracranial aneurysms with flow-diverters.

METHODS

Six Pipeline Flex embolization devices (PED-Flex), six PED with Shield technology (PED-Shield), and four Solitaire AB devices were implanted in the carotid arteries (two stents per vessel) of four pigs. Intravascular optical coherence tomography (OCT) and digital subtraction angiography (DSA) images obtained on day 21 were compared to histological specimens.

RESULTS

A case of ISS in a PED-Flex device was assessed with OCT imaging. Neointima with asymmetrical topography completely covering the PED struts was observed. Histological preparations of the stenotic area demonstrated thrombus on the surface of device struts, covered by neointima.

CONCLUSION

This study provides a plausible concept for reversible ISS in flow-diverters. Based on an observation of a previous experiment, we propose that similar cases of ISS are related to thrombus presence underneath endothelization, but further experiments focused on this phenomenon are needed. Optical Coherence Tomography will be useful tool when available for clinical use.

Pipeline Embolization device for intracranial aneurysms in a large Chinese cohort: factors related to aneurysm occlusion

Background and Purpose:

The Pipeline Embolization Device (PED, Covidien/Medtronic) is widely used to treat intracranial aneurysms. This PED in China post-market multi-center registry study (PLUS) investigated safety and effectiveness of the PED for intracranial aneurysms in the Chinese population.

Methods:

This was a panoramic, consecutive, real-world cohort registry study. Patients treated with PED with or without coils between November 2014 and October 2019 at 14 centers in China were included, and those treated by parent vessel occlusion or other stents were excluded. Study outcomes included angiographic evaluation of aneurysm occlusion, complications, in-stent stenosis, and predictors of aneurysm occlusion. A central committee reviewed all imaging and endpoint events.

Results:

In total, 1171 patients with 1322 intracranial aneurysms were included. The total occlusion rate was 81.4% (787/967) at mean follow-up of 8.96 ± 7.50 months, with 77.1% (380/493) occlusion in the PED alone and 85.9% (407/474) in the PED plus coiling group. On multi-variate analysis, female sex, hyperlipidemia, vertebral aneurysms, PED plus coiling, and blood flow detained to venous phase were significant predictors of aneurysm occlusion. In posterior circulation cohort, there was no variable associated with aneurysm occlusion. In-stent stenosis predictors included current smoking and cerebral sclerosis/stenosis.

Conclusion:

In the largest series on PED of multi-center date of China, data suggest that treatment with the flow-diverting PED in intracranial aneurysms was efficacious. The treatment of PED combined coiling and blood flow detained to venous phase after PED implant were associated with aneurysmal occlusion. The occlusion rate of vertebral aneurysms was higher than other location aneurysms.

Clinical Trial Registration:

ClinicalTrials.gov identifier: NCT03831672.

Pipeline Flex embolisation device with Shield Technology for the treatment of patients with intracranial aneurysms: periprocedural and 6 month outcomes

BACKGROUND AND PURPOSE

The Pipeline Flex embolisation device with Shield Technology (Pipeline Shield) is a novel flow diverter which reduces intra-vessel thrombogenicity. This study summarises periprocedural outcomes and 6-month follow-up results following its introduction in a tertiary interventional neuroradiology centre.

MATERIALS AND METHODS

This prospective, single-arm study assessed 32 aneurysms treated over a 21-month time period from the time of procedure to 6 months post-procedure. Data collected included patient demographics, aneurysm features and intraprocedural and 6-month post-procedural complications.

RESULTS

The mean age of the cohort was 58.8 ± Standard Deviation 8.5 years. Twenty-eight aneurysms were treated electively and four acutely. The elective cases received dual antiplatelet therapy post-procedure. The acute cases received single antiplatelet therapy post-procedure. Of the target aneurysms, 16/32 (50%) were small (<10 mm), 13/32 (41%) were large (10-25 mm) and 3/32 (9%) were giant (≥25 mm). There was no mortality in the series. There were two periprocedural complications (2/32, 6.2%): a stroke and a dissection. There were no post-procedural complications. At 6 months post-procedure, satisfactory occlusion (defined as Raymond-Roy 1 or 2) was achieved in 90.6% and 93.8% by way of magnetic resonance angiography and digital subtraction angiography assessment, respectively. There was no implant migration, no significant intraluminal hyperplasia or in-stent stenosis and no cases of aneurysm recurrence.

CONCLUSION

The Pipeline Shield has an excellent 6- month safety profile with an acceptable rate of intraprocedural complications, no post-procedure complications and no mortality in this case series of 32 acute and elective cases.

A Patient with a Large Aneurysm Complicated by Stenosis of the Internal Carotid Artery Distal to the Aneurysm in Whom Treatment Using a Pipeline Flex Was Performed

Objective

We report a case of in-stent stenosis as a complication at 6 months after the deployment of Pipeline Flex. This case necessitated retreatment for parent artery occlusion.

Case Presentation

A 55-year-old woman with right-side visual disorder was referred to our hospital for the deployment of Pipeline Flex. Cerebral digital subtraction angiography (DSA) demonstrated a large right-side paraclinoid aneurysm in combination with severe internal carotid artery (ICA) stenosis just beyond the aneurysm. We deployed Pipeline Flex under general anesthesia. After deployment, we performed angioplasty through the Pipeline. Six months after deployment, this patient exhibited exacerbation of visual disorder. Follow-up DSA revealed in-stent stenosis at 6 months after the deployment of Pipeline Flex. Therefore, we performed parent artery occlusion. Right-side visual disorder was improved in this patient.

Conclusion

If Pipeline is deployed for patients with ICA stenosis just beyond an aneurysm, we need to be aware of in-stent stenosis after deployment.

Safety and efficacy of the Silk flow diverter: Insight from the DIVERSION prospective cohort study

BACKGROUND AND PURPOSE

Flow diverters are considered as an essential tool in the stent-based treatment of complex intracranial aneurysms. We report here a subgroup analysis of the nationwide prospective DIVERSION study to investigate the safety and efficacy of the Silk flow diverter at 12 months follow-up.

METHODS

We performed a subgroup analysis of patients included in the DIVERSION, a national prospective cohort study including all flow diverters placement between 2012 and 2014 in France, and treated with the Silk. The primary outcome was the morbi-mortality at 12 months, including death, morbidity event and aneurysm retreatment within 12 months post-treatment. All reported serious events were adjudicated by an independent Data Safety and Monitoring Board. Satisfactory occlusion was defined as 3 or 4 on Kamran's scale by an independent imaging core laboratory during follow-up.

RESULTS

A total of 102 procedures involving 101 patients (mean age±standard deviation, 54.3±13.5 years) harbouring 118 aneurysms (113/118 located in the anterior circulation; mean size 8.2±7.1mm) were included. During the 12-month follow-up, 34 (33.3%) procedures experienced at least one morbi-mortality event: 3 deaths, 27 morbidity events and 4 retreatments. Overall, 1/3 deaths and 10/27 morbidity events were related to the device and/or the procedure, leading to a specific survival rate and a specific free-morbidity survival rate at 12 months of 98.98% [95% confidence interval, 92.98%-99.86%] and 89.73% [95%CI, 81.71%-94.36%], respectively. The rate of permanent-related neurological deficit was 5.9% within 12 months. One year follow-up imaging showed satisfactory occlusion in 82.2% of cases.

CONCLUSION

Flow diversion with the Silk device has a reasonable safety and effectiveness profile for the endovascular treatment of intracranial aneurysms.

Treatment of Extracranial Vertebral Artery Aneurysm with Flow Diversion

BACKGROUND

Aneurysms of the extracranial vertebral artery are rare, and the treatment options are not standardized. We present a case of an extracranial vertebral artery aneurysm treated with flow diversion.

CASE DESCRIPTION

In a 72-year-old woman, computed tomography angiography demonstrated a right extracranial vertebral artery aneurysm. The saccular aneurysm (7.9 × 6.6 mm) was demonstrated on digital subtraction angiography at the V3 segment of the right vertebral artery. A Pipeline embolization device was placed in the diseased parent artery. The patency of the Pipeline embolization device was confirmed at 12-month follow-up.

CONCLUSIONS

Flow diversion is a simple and promising treatment option for a V3 segment aneurysm. Postoperative asymptomatic partial in-stent stenosis is tolerable.

Predictors of Complications, Functional Outcome, and Morbidity in a Large Cohort Treated With Flow Diversion

BACKGROUND

A dramatic improvement in obliteration rates of large, wide-necked aneurysms has been observed after the FDA approved the Pipeline Embolization Device (PED) in 2011.

OBJECTIVE

To assess the predictors of complications, morbidity, and unfavorable outcomes in a large cohort of patients with aneurysms treated with PED.

METHODS

A retrospective chart review of a prospectively maintained database for subjects treated with flow diversion from 2010 to 2019.

RESULTS

A total of 598 aneurysms were treated during a period extending from 2010 to 2019 (84.28% females, mean age 55.5 yr, average aneurysm size 8.49 mm). Morbidity occurred at a rate of 5.8% and mortality at a rate of 2.2%. Ischemic stroke occurred at a rate of 3%, delayed aneurysmal rupture (DAR) at 1.2%, and distal intraparenchymal hemorrhage (DIPH) at 1.5%. On multivariate analysis, the predictor of stroke was aneurysm size &gt;15 mm. Predictors of DAR were previous subarachnoid hemorrhage (SAH), increasing aneurysm size, and posterior circulation aneurysm. Predictors of DIPH were using more than 1 PED and baseline P2Y12 value. Predictors of in-stent stenosis were the increasing year of treatment and balloon angioplasty, whereas increasing age and previous treatment were negatively associated with in-stent stenosis. Predictors of morbidity were posterior circulation aneurysms, increasing aneurysm size, and hypertension, and incidental aneurysm diagnosis was protective for morbidity.

CONCLUSION

Flow diversion is a safe and effective treatment option for aneurysms. A better understanding of predictive factors of complications, morbidity, and functional outcomes is of high importance for a more accurate risk assessment.

Pipeline Flex Embolization Device (PED Flex) for the treatment of intracranial aneurysms: Periprocedural outcomes and first-year angiographic results

Background/aim

The Pipeline Flex Embolization Device (PED Flex) is a new updated version of the PED classic that incorporates a new delivery system to allow facilitation of stent deployment, resheathing, and removal of the capture coil. This study evaluated the PED Flex in terms of the technical aspects of the procedure and first-year follow-up results.

Materials and methods

This retrospective study involved prospectively collected data from May 2015 to August 2017. The primary endpoint was technical aspects of the procedure, and the secondary endpoint was first-year follow-up results.

Results

Forty-nine patients with 59 target intracranial aneurysms were enrolled. Patients’ mean age was 52 years (range 21−71 years), and 31 (63.0%) were female. All aneurysms except for three were unruptured. The mean aneurysm diameter was 8 mm. Forty-seven patients with 56 aneurysms were successfully treated. Due to advancement, repositioning, and migration problems, 8 (13.1%) stents were not deployed and discharged. The total aneurysm occlusion rate was 77.0%. The mortality rate was 4.3%.

Conclusion

Our experience shows that the applicability and safety of the renewed delivery system provided by PED Flex for improving device apposition and opening has been proven with one-year angiographic and clinical follow-up results.

Flow Diverters for Intracranial Aneurysms

Background and Purpose—

Flow diverters are used for endovascular therapy of intracranial aneurysms. We did a nationwide prospective study to investigate the safety and effectiveness of flow diversion at 12 months.

Methods—

DIVERSION was a national prospective cohort study including all flow diverters placement between October 2012 and February 2014 in France. The primary end point was the event-free survival rate at 12 months, defined as the occurrence of morbidity (intracranial hemorrhage, ischemic stroke, noncerebral hemorrhage, or neurological deficit due to mass effect), retreatment, or death within 12 months post-treatment. A quality control was carried out on 100% of the collected data and of at least 10% of the included patients in each center, chosen at random. All reported serious events were adjudicated by an independent Data Safety and Monitoring Board. Satisfactory occlusion was defined as 3 or 4 on Kamran scale by an independent imaging core laboratory at 12 months.

Results—

We enrolled 398 patients harboring 477 intracranial aneurysms. At least 1 morbidity-mortality event was noted in 95 of 408 interventions representing an event-free survival rate of 75.7% (95% CI, 71.1–79.7). The rate of permanent-related serious events and mortality was 5.9% and 1.2% at 12 months, respectively. Multivariate analysis showed that high baseline blood pressure (hazard ratio, 2.54; 95% CI, 1.35–4.79; P =0.039), diabetes mellitus (hazard ratio, 3.70; 95% CI, 1.60–8.6; P =0.0022), and larger aneurysms (hazard ratio, 1.07; 95% CI, 1.04–1.11; P <0.0001) were associated with the occurrence of a neurological deficit. The satisfactory occlusion rate at 12 months was 79.9%, and the absence of high baseline blood pressure (odds ratio, 2.01; 95% CI, 1.12–3.71; P =0.0193) and postprocedural satisfactory occlusion (odds ratio, 2.75; 95% CI, 1.49–5.09; P =0.0012) were associated with a 12-month satisfactory occlusion.

Conclusions—

A satisfactory occlusion was achieved in almost 80% of cases after flow diverter treatment with a permanent-related serious event and mortality rates of 5.9% and 1.2% at 12 months, respectively.

Outcome of intracranial flow diversion according to the antiplatelet regimen used: a systematic review and meta-analysis

Background

Thromboembolic complications are not uncommon in patients undergoing neurointerventional procedures. The use of flow diverting stents is associated with higher risks of these complications despite current dual antiplatelet regimens.

Objective

To explore contemporary evidence on the safety of emerging dual antiplatelet regimens in flow diverting stenting procedures.

Methods

We performed a systematic review and meta-analysis to identify relevant articles in electronic databases, and relevant references. Studies reporting the complications and mortality of flow diverting stenting procedures using acetyl salicylic acid (ASA) + ticagrelor or ASA + prasugrel compared with ASA + clopidogrel were included.

Results

Of 452 potentially relevant studies, we identified 49 studies (2526 patients) which reported the safety of ticagrelor or prasugrel for pooled analysis, and five studies (1005 patients) for meta-analysis. The pooled overall mortality in all studies was 2.14%, ischemic complications 6.89%, and hemorrhagic complications 3.68%. The use of ticagrelor or prasugrel was associated with a lower risk of mortality compared with clopidogrel (RR=4.57, 95% CI 1.23 to 16.99; p=0.02). Considering ischemic events, ASA + clopidogrel was as safe as ASA + prasugrel (RR=0.55, 95% CI 0.11 to 2.74; p=0.47) and ASA + ticagrelor (RR=0.74, 95% CI 0.32 to 1.74; p=0.49). ASA +ticagrelor was not associated with a higher risk of hemorrhagic complications (RR=0.92, 95% CI 0.27 to 3.16; p=0.89).

Conclusions

Evidence suggests that dual antiplatelet regimens including ticagrelor or prasugrel are safe for patients undergoing flow diversion procedures. Regimens using ticagrelor were associated with better survival than those using clopidogrel in the included studies.

Management of antiplatelet therapy in patients undergoing neuroendovascular procedures

Neuroendovascular techniques for treating cerebral aneurysms and other cerebrovascular pathology are increasingly becoming the standard of care. Intraluminal stents, aneurysm coils, and other flow diversion devices typically require concomitant antiplatelet therapy to reduce thromboembolic complications. The variability inherent with the pharmacodynamic response to common antiplatelet agents such as aspirin and clopidogrel complicates optimal selection of antiplatelet agents by clinicians. This review serves to discuss the literature related to antiplatelet use in neuroendovascular procedures and provides recommendations for clinicians on how to approach patients with variable response to antiplatelet agents, particularly clopidogrel.

Treatment of intracranial aneurysms using the pipeline flex embolization device with shield technology: angiographic and safety outcomes at 1-year follow-up

PURPOSE

The Pipeline Embolization Device (PED) is a routine first-line treatment option for intracranial aneurysms (IAs). The Pipeline Flex Embolization Device with Shield Technology (Pipeline Shield) is an updated version of the PED which has been modified to include a surface phosphorylcholine biocompatible polymer. Its early technical success and safety have been reported previously. Here, we assessed the long-term safety and efficacy of the Pipeline Shield for the treatment of IAs.

MATERIALS AND METHODS

The Pipeline Flex Embolization Device with Shield Technology (PFLEX) study was a prospective, single-arm, multicenter study for the treatment of unruptured IAs using the Pipeline Shield. The primary endpoint was a major stroke in the territory supplied by the treated artery or neurologic death at 1-year post-procedure. Angiographic outcomes were also assessed by an independent radiology laboratory at 6 months and 1 year.

RESULTS

Fifty patients (mean age, 53 years; 82% female) with 50 unruptured IAs were treated. Mean aneurysm diameter was 8.82±6.15 mm. Of the target aneurysms, 38/50 (76%) were small (<10 mm), 11/50 (22%) were large (≥10 and<25 mm), and 1/50 (2%) was giant (≥25 mm). Forty-seven (94%) were located in the internal carotid artery and three (6%) in the vertebral artery. At 1-year post-procedure, no major strokes or neurologic deaths were reported, and complete occlusion was achieved in 27/33 (81.8%). There were no instances of aneurysm recurrence or retreatment.

CONCLUSIONS

Our 1-year follow-up concerning angiographic and safety outcomes corroborate previous evidence that the Pipeline Shield is a safe and effective treatment for IAs.

TRIAL REGISTRATION NUMBER

NCT02390037.

Rapid ventricular pacing for clip reconstruction of complex unruptured intracranial aneurysms: results of an interdisciplinary prospective trial

OBJECTIVE

To date, treatment of complex unruptured intracranial aneurysms (UIAs) remains challenging. Therefore, advanced techniques are required to achieve an optimal result in treating these patients safely. In this study, the safety and efficacy of rapid ventricular pacing (RVP) to facilitate microsurgical clip reconstruction was investigated prospectively in a joined neurosurgery, anesthesiology, and cardiology study.

METHODS

Patients with complex UIAs were prospectively enrolled. Both the safety and efficacy of RVP were evaluated by recording cardiovascular events and outcomes of patients as well as the amount of aneurysm occlusion after the surgical clip reconstruction procedure. A questionnaire was used to evaluate aneurysm preparation and clip application under RVP.

RESULTS

Twenty patients (mean age 51.6 years, range 28–66 years) were included in this study. Electrode positioning was easy in 19 (95%) of 20 patients, and removal of electrodes was easily accomplished in all patients (100%). No complications associated with the placement of the pacing electrodes occurred, such as cardiac perforation or cardiac tamponade. RVP was applied in 16 patients. The mean aneurysm size was 11.1 ± 5.5 mm (range 6–30 mm). RVP proved to be a very helpful tool in aneurysm preparation and clip application in 15 (94%) of 16 patients. RVP was used for a mean duration of 60 ± 25 seconds, a mean heart rate of 173 ± 23 bpm (range 150–210 bpm), and a reduction of mean arterial pressure to 35–55 mm Hg. RVP leads to softening of the aneurysm sac facilitating its mobilization, clip application, and closure of the clip blades. In 2 patients, cardiac events were documented that resolved without permanent sequelae in both. In every patient with successful RVP (n = 14) a total or near-total aneurysm occlusion was documented. In the 1 patient in whom the second RVP failed due to pacemaker electrode dislocation, additional temporary clipping was required to secure the aneurysm, but was not as sufficient as RVP. This led to an incomplete clipping of the aneurysm and finally a remnant on postoperative digital subtraction angiography. A pacemaker lead dislocation occurred in 3 (19%) of 16 patients, but intraoperative repositioning requires less than 20 seconds. Outcome was favorable in all patients according to the modified Rankin Scale.

CONCLUSIONS

To the best of the authors’ knowledge this is the first prospective interdisciplinary study of RVP use in patients with UIAs. RVP is an elegant technique that facilitates clip reconstruction in complex UIAs. The safety of the procedure is good. However, because this procedure requires extensive preoperative cardiological workup of the patient and an experienced neurosurgery and neuroanesthesiology team with much cerebrovascular expertise, actually it remains reserved for selected elective cases and highly specialized centers.

Clinical trial registration no.: NCT02766972 (clinicaltrials.gov)

Flow diversion with the pipeline embolization device for patients with intracranial aneurysms and antiplatelet therapy: A systematic literature review

Flow diversion with the Pipeline Embolization Device (PED) is reported as a safe and efficient treatment for patients with intracranial aneurysms; however, literature discussing the antiplatelet (APT) regimen used before and after the PED is limited. Our aim was to systematically review and summarize available data regarding the APT regimen and the platelet function test (PFT) that was used. We also sought to provide an overview of the aneurysm morphologies and adverse event rates associated with the PED use. This systematic review was conducted according to the PRISMA statement and eligible studies were identified through search of the PubMed and Cochrane databases. We reviewed 28 studies, involving 1556 patients that underwent aneurysm treatment with the PED. The preprocedural aspirin (ASA) 300- 325mg (2-14days) combined with clopidogrel 75mg (3 to >10days) were used as a treatment strategy in 61.7% of patients and ASA 81mg with clopidogrel 75mg for 5-10days for 27%. Patients who received low versus high dose pre-PED ASA, were at less risk for a hemorrhagic event (0.7% versus 3.3%, p=0.053); however no statistical significance was reached. There was also lack of relationship between patients that received low versus high preprocedural ASA in terms of thromboembolic events. Regarding postprocedural APT, ASA (>6months) and clopidogrel (3- 12 months) was the regimen of choice for 93% of patients. Most studies conducted at least one PFT, most common being the VerifyNow. The most frequently reported target P2Y12 Reaction unit (PRU) and Aspirin Reaction Unit (ARU) values were <230 and <550 respectively. There was no statistically demonstrable difference in regards to thrombotic events between centers that conducted at least one PFT and centers that did not test their patients with a PFT. The overall rates of symptomatic thrombotic episodes were 6.6% and hemorrhagic were 3%. The pre- and post-PED APT dose and duration varies across different institutions. More prospective studies are needed to compare the efficacy of different APT agents and reach conclusions regarding use of PFT and platelet reaction values in order to decrease hemorrhagic and thromboembolic complications associated with the PED.

Ultrasound for the evaluation of stenosis after flow diversion

Background and purpose

Flow diversion is a relatively new strategy used to treat complex cerebral aneurysms. The optimal method for radiographic follow-up of patients treated with flow diverters has not been established. The rate and clinical implications of in-stent stenosis for these devices is unclear. We evaluate the use of transcranial Doppler ultrasound (TCD) for follow-up of in-stent stenosis.

Materials and methods

We analyzed 28 patients treated with the Pipeline embolization device (PED) over the course of 42 months from January 2009 to June 2012. Standard conventional cerebral angiograms were performed in all patients. TCD studies were available in 23 patients.

Results

Angiographic and TCD results were compared and found to correlate well.

Conclusions

TCD is a potentially useful adjunct for evaluating in-stent stenosis after flow diversion.

Tourniquet parent artery occlusion after flow diversion

BACKGROUND

The Pipeline Embolization Device (PED) is increasingly used for both on- and off-label purposes for treatment of intracranial aneurysms. The device gradually slows flow of blood into the aneurysm, but the high metal coverage of PED promotes endothelialization of the device. Occasionally, this leads to in-stent stenosis that is clinically well tolerated. We present a multi-institutional Pipeline series that includes three cases of gradual asymptomatic occlusion within the PED and parent vessel.

METHODS

Institutional databases at each participating center were searched for patients treated with the PED. Patients with at least 50% stenosis or occlusion were selected and all relevant clinical and radiographic data were reviewed.

RESULTS

A total of 326 cases performed by five neurointerventionalists across four institutions were reviewed. Among these there were three cases of complete occlusion and two cases of stenosis of more than 50%, for an occlusion rate of 0.9%. All patients were clinically asymptomatic.

CONCLUSIONS

A gradual tourniquet-like occlusion can occur following placement of the PED, leading to vessel occlusion. This has been clinically well tolerated by patients in our series due to the formation of pial collaterals as the stenosis progresses, likely due to ischemic preconditioning. Small parent vessel, pre-existing stenosis, fusiform pathology, overlapping devices, and suboptimal antiplatelet therapy seem to be predisposing factors. Further experience and follow-up will allow us to characterize the risk factors and optimize post-procedural therapy for these patients.

Republished: Rapid delayed growth of ruptured supraclinoid blister aneurysm after successful flow diverting stent treatment

A 62-year-old woman presented with a subarachnoid hemorrhage secondary to a ruptured right supraclinoid internal carotid artery blister aneurysm. She was treated in an emergent fashion with two flow diverting pipeline embolization devices (PED) deployed in a telescoping fashion. CT angiography performed for unrelated reasons at 7 months showed successful treatment of the aneurysm without evidence of residual aneurysm. However, a follow-up digital subtraction angiogram performed at 9 months showed a large aneurysm in a modified position compared with the original aneurysm. This is the first case of rapid regrowth of a supraclinoid blister aneurysm after successful treatment with a PED, and demonstrates the need for close follow-up for similar aneurysms treated with this novel device.

Rapid delayed growth of ruptured supraclinoid blister aneurysm after successful flow diverting stent treatment

A 62-year-old woman presented with a subarachnoid hemorrhage secondary to a ruptured right supraclinoid internal carotid artery blister aneurysm. She was treated in an emergent fashion with two flow diverting pipeline embolization devices (PED) deployed in a telescoping fashion. CT angiography performed for unrelated reasons at 7 months showed successful treatment of the aneurysm without evidence of residual aneurysm. However, a follow-up digital subtraction angiogram performed at 9 months showed a large aneurysm in a modified position compared with the original aneurysm. This is the first case of rapid regrowth of a supraclinoid blister aneurysm after successful treatment with a PED, and demonstrates the need for close follow-up for similar aneurysms treated with this novel device.