Pipeline Embolization Device for Intracranial Aneurysms in a Large Chinese Cohort: Complication Risk Factor Analysis

Neuroform atlas stent treatment for 533 intracranial aneurysms in a large Chinese cohort: complication risk factor analysis

BACKGROUND

The newest generation of Neuroform Atlas stent™ (Stryker, Fremont, California) represents a recent advance of cerebral laser-cut microstents for the treatment of intracranial wide-necked aneurysms, and postoperative complications have been observed among Western patients. We assessed predictors of complications, morbidity, and unfavourable outcomes in a large cohort of patients with aneurysms that were treated with Neuroform Atlas stents in China.

METHODS

This retrospective study included subjects who were treated with Atlas stents in China from November 2020 to January 2022.

RESULTS

A total of 522 consecutive patients (mean age, 58.9 ± 9.9 years; female, 65.3% [341/522]) with 533 aneurysms were included in the study. In the early postoperative period, the neurological morbidity rate was 7.3% (38/522), the ischaemic stroke rate was 5.0% (26/522), the aneurysm rupture subarachnoid haemorrhage rate was 2.3% (12/522), and the mRS score deterioration rate was 5.4% (28/522). The mortality rate was 0.8% (4/522) in the postoperative period. The rate of neurological morbidity during the follow-up period was 1.2% (6/486). In the multifactor prediction analysis, cerebral infarction, Hunt-Hess grade (3-5), procedure duration, stent length and coil protrusion into the parent artery were found to be independent predictors of neurologic morbidity. The procedure duration, stent length and coil protrusion into the parent artery were found to be independent predictors of mRS score deterioration.

CONCLUSIONS

The incidence of SCA (stent-assisted coiling)-related complications with the Atlas stent in this study population was comparable to that in Western populations. We identified the procedure duration and stent length as novel independent predictors of SCA-related ischaemic stroke, neurological morbidity, and mRS score deterioration among the Chinese population.

Clinical Outcomes On Tubridge Flow Diverter in Treatmenting Intracranial Aneurysms: a Retrospective Multicenter Registry Study

PURPOSE

In China, the application of nitinol Tubridge flow diverter (TFD) has become popular for treating intracranial aneurysms (IAs). In this study, we investigated the safety outcomes of the application of TFD for treating IAs in real-world scenarios.

METHODS

We retrospectively analyzed aneurysms treated with TFD in 235 centers throughout China between April 2018 and April 2020. The primary endpoint was the event-free survival rate at 12 months, defined as the occurrence of morbidity (spontaneous rupture, intraparenchymal hemorrhage (IPH), ischemic stroke, and permanent cranial neuropathy) or death. Univariate and multivariate analyses were performed to assess the risk factors. A good outcome was defined as a modified Rankin Score (mRS) of 0-2.

RESULTS

We included 1281 unruptured aneurysms treated with TFD. The overall neurological morbidity and death rates after 12 months were 5.4 and 2.8%, respectively. Ischemic strokes were the most common complication (4.2%, P < 0.001). Cranial neuropathy, IPH, and spontaneous rupture occurred in 0.3%, 0.3%, and 0.5% of aneurysms, respectively. Univariate and multivariate analyses indicated that the male gender, older age, larger aneurysm diameter, and aneurysm located on BA were the independent risk factors for neurologic events. Aneurysm located on BA was the independent risk factor for ischemic strokes. Most patients (1222) had access to the mRS, and 93.2% of them achieved good outcomes.

CONCLUSION

Treatment of IAs with TFD was associated with low morbidity and mortality, most of which were ischemic events. Large posterior aneurysms might be associated with a higher complication rate.

TRIAL REGISTRATION

Retrospectively registered.

Flow Diverter Combined with Coil Embolization for Acutely Ruptured Intracranial Aneurysms: A Single Center Experience

BACKGROUND

Extensive research has confirmed the safety and effectiveness of flow diverters in the treatment of unruptured intracranial aneurysms. However, their use in cases of acute rupture remains a subject of debate.

METHODS

This study was conducted as a single-center retrospective investigation from January 2018 to January 2022 and included patients with acutely ruptured intracranial aneurysms (within three days of rupture) who were treated using the Pipeline Embolization Device with adjunctive coil embolization. Patient demographics, operative procedures, and outcomes were analyzed. Antiplatelet therapy included intra-arterial tirofiban and postoperative dual therapy with clopidogrel and aspirin.

RESULTS

A total of 21 patients (5 males, 16 females) diagnosed with acutely ruptured intracranial aneurysms were included in this study. The aneurysm types included 7 blood blister-like aneurysms (30.0%), 3 dissecting (14.3%), and 1 fusiform aneurysm (4.8%). Perioperative complications occurred in 2 patients (9.5%), and both cases involved thrombogenesis. Nineteen patients completed digital subtraction angiography during follow-up, with an average follow-up time of 8.7 months (5 - 18 months). Results showed a complete embolization rate of 94.7% (18/19), with a partial aneurysm still present in 1 patient. A total of 90.4% (19/21) of patients had a favorable prognosis (modified Rankin Scale score = 0 - 2).

CONCLUSIONS

The Pipeline Embolization Device with adjunctive coil embolization proved to be a viable option for managing acutely ruptured intracranial aneurysms, notwithstanding the potential for ischemic complications.

Treatment of intracranial aneurysms with pipeline embolization device: a single-center experience

Background

Endovascular therapy is the primary treatment modality for intracranial aneurysms (IA). The objective of this study was to assess the effectiveness and safety of a pipeline embolization device (PED) for the treatment of IA.

Methods

This retrospective study was conducted at a single center. Data were collected for all patients who underwent PED treatment at the Fourth Affiliated Hospital of Xinjiang Medical University between December 2018 and January 2022. Clinical characteristics, aneurysm-related characteristics, treatment details, and clinical and imaging outcomes were collected and analyzed.

Results

A total of 60 consecutive patients with 60 IAs were treated with a PED. The mean age of the participants was 61.8 years, with 53% being female. The average size of the aneurysms was 14.7 mm, with 54 located in the anterior circulation and six in the posterior circulation. The median last follow-up time was 13.0 months (range, 11-24 months). All patients underwent final digital subtraction angiography (DSA) for angiographic follow-up, and 50 aneurysms (83.3%) were completely occluded. The overall complication rate was 3.3%, and there were no reported mortalities. Among the 12 cases of ruptured aneurysms, all of which underwent adjunctive coil embolization, the complete occlusion rate was 91.7% with a complication rate of 16.6% [ischemic complication and modified Rankin scale (mRS) deteriorated]. In the 6 cases of posterior circulation aneurysms (2 in the basilar artery), 5 cases achieved complete occlusion and 1 case achieved near-complete occlusion, with no reported complications or mortality.

Conclusions

The use of PEDs appears to be an effective treatment option for IA, demonstrating high occlusion rates and low complication rates. While the application of PEDs for the treatment of ruptured aneurysms did not increase the risk of secondary aneurysm rupture, caution is still warranted due to a higher complication rate. In the treatment of aneurysms of the vertebrobasilar artery using PEDs, this study achieved favorable efficacy outcomes without complications nor patient mortality. However, further studies are needed to validate these findings.

Comparison of pipeline embolization device and tubridge flow diverter for posterior circulation aneurysms: A multicentre propensity score matched study

Rationale and objectives

The off-label use of flow diverters (FDs) has broadened to include treating aneurysms in posterior circulation (PC). A novel flow diverter, the Tubridge flow diverter (TFD), has been created in China specifically for treating PC aneurysms. However, studies comparing between pipeline embolization device (PED) and TFD are rare. Thus, our study aimed to explore the effectiveness of PED and TFD in the treatment of PC aneurysms using a propensity score matched cohort design.

Methods

Retrospective data collection was conducted on patients who underwent treatment with either PED or TFD over the period from 2015 through 2020. Propensity score matching (PSM) was employed to calibrate for patient age; history of ischemic stroke; aneurysm size; morphology; location and neck; number of FDs; parent vessel diameter; and the employment of assisted coiling and balloon techniques. Data on previously ruptured aneurysms was not included in the analysis. A comparison was conducted between the two devices to assess perioperative complications, aneurysm occlusion rates, and functional outcomes.

Results

A total of 252 PC aneurysms were treated in 248 patients. Clinical and imaging follow-ups were lost in 26 and 47 patients, respectively. Major perioperative complications occurred in 7.5% of the cases, with favorable clinical outcomes in 91.0% and complete occlusion in 79.1%. Eighty-two (32.5%) aneurysms were treated with TFD, while 170 (67.5%) aneurysms were treated with PED. PSM was used to account for these significant variations, producing 82 matched pairs of unruptured aneurysms treated with PED or TFD. In terms of functional and angiographic outcomes, no significant differences were found between PED and TFD (functional outcome, p = 0.594 and angiographic outcome, p = 0.415). However, more perioperative major complications were found in patients treated with TFD (p = 0.005) compared with those receiving PED.

Conclusion

The comparative study of PED and TFD in the treatment of PC aneurysms resulted in positive clinical results and sustained occlusion rates, with acceptable perioperative complications. However, higher quality studies are needed to enhance our understanding of the use of FDs for treating of PC aneurysms.

Predicting postinterventional rupture of intracranial aneurysms using arteriography-derived radiomic features after pipeline embolization

Background and purpose

Postinterventional rupture of intracranial aneurysms (IAs) remains a severe complication after flow diverter treatment. However, potential hemodynamic mechanisms underlying independent predictors for postinterventional rupture of IAs remain unclear. In this study, we employed arteriography-derived radiomic features to predict this complication.

Methods

We included 64 patients who underwent pipeline flow diversion for intracranial aneurysms, distinguishing between 16 patients who experienced postinterventional rupture and 48 who did not. We performed propensity score matching based on clinical and morphological factors to match these patients with 48 patients with postinterventional unruptured IAs at a 1:3 ratio. Postinterventional digital subtraction angiography were used to create five arteriography-derived perfusion parameter maps and then radiomics features were obtained from each map. Informative features were selected through the least absolute shrinkage and selection operator method with five-fold cross-validation. Subsequently, radiomics scores were formulated to predict the occurrence of postinterventional IA ruptures. Prediction performance was evaluated with the training and test datasets using area under the curve (AUC) and confusion matrix-derived metrics.

Results

Overall, 1,459 radiomics features were obtained, and six were selected. The resulting radiomics scores had high efficacy in distinguishing the postinterventional rupture group. The AUC and Youden index were 0.912 (95% confidence interval: 0.767-1.000) and 0.847 for the training dataset, respectively, and 0.938 (95% confidence interval, 0.806-1.000) and 0.800 for the testing dataset, respectively.

Conclusion

Radiomics scores generated using arteriography-derived radiomic features effectively predicted postinterventional IA ruptures and may aid in differentiating IAs at high risk of postinterventional rupture.

Pipeline Embolization Device for intracranial aneurysms presenting with mass effect: a large Chinese cohort

BACKGROUND

Unruptured intracranial aneurysm treatment aims to reduce the risk of aneurysm rupture and bleeding, relieves symptoms and improve the quality of life for patients. This study aimed to assess the safety and efficacy of Pipeline Embolization Device (PED, Covidien/Medtronic, Irvine, CA) treatment for intracranial aneurysms presenting with mass effect in real-world settings.

METHODS

We selected patients from the PED in China Post-Market Multi-Center Registry Study with mass effect presentation. The study endpoints included postoperative mass effect deterioration and mass effect relief at follow-up (3-36 months). We conducted multivariate analysis to identify factors associated with mass effect relief. Subgroup analyses by aneurysm location, size and form were also performed.

RESULTS

This study included 218 patients with a mean age of 54.3±11.8 years and a female predominance of 74.0% (162/218). The postoperative mass effect deterioration rate was 9.6% (21/218). During a median follow-up period of 8.4 months, the mass effect relief rate was 71.6% (156/218). Notably, immediate aneurysm occlusion following treatment was significantly associated with mass effect relief (OR 0.392, 95% CI, 0.170 to 0.907, p=0.029). Subgroup analysis demonstrated that adjunctive coiling contributed to mass effect relief in cavernous aneurysms, while dense embolism impeded symptom relief in aneurysms<10 mm and saccular aneurysms.

CONCLUSIONS

Our data confirmed the efficacy of PED in relieving mass effect. The findings of this study provide support for endovascular treatment to alleviate mass effect in unruptured intracranial aneurysms.

TRIAL REGISTRATION NUMBER

NCT03831672.

Flow-diverter stents in intracranial aneurysm treatment: impact on covered cerebral artery branches

OBJECTIVE

Flow diverter stents (FDSs) have attracted interest for intracranial aneurysm (IA) treatment; however, occlusion of side branches and related complications have been reported. This study aimed to investigate the effects of FDSs in IA management when different branches of intracranial arteries are covered.

MATERIALS AND METHODS

A cross-sectional study was conducted using PUBMED, Embase, Web of Science, and Cochrane databases to include randomized or nonrandomized comparative-designed studies from January 2000 to August 2022 which reported outcomes of occlusion/narrowing of branches after IA treatment using FDSs. The PRISMA guidelines were used for our report. A random-effects meta-analysis was conducted to pool the outcomes, which included incidence rates of occlusion/narrowing of FDS-covered branches, branch occlusion-related symptoms, obliteration of IAs, and ideal clinical outcomes (modified Rankin Scale score ≤2).

RESULTS

The authors identified 57 studies involving 3789 patients with IA managed by FDSs covering different branches. During the median imaging follow-up at 12 months, the IA obliteration rate was satisfactory (>70%) when covering the ophthalmic artery (OA), posterior communicating artery (PComA), anterior choroidal artery (AChoA) or anterior cerebral artery (ACA), but not the middle cerebral artery-M2 segment (MCA-M2; 69.5%; 95% CI: 60.8-77.5%) and posterior inferior cerebellar artery (PICA; 59.1%, 13/22). The overall ideal clinical outcome was observed in 97.4% of patients (95% CI: 95.5-98.9%). Higher rates of occlusion/narrowing of branches were identified when FDSs covered the ACA (66.6%; 95% CI: 45.1-85.3%), PComA (44.3%; 95% CI: 34.2-54.6%), or MCA-M2 (39.2%; 95% CI: 24.5-54.7%); the risks were lower when covering the OA (11.8%; 95% CI: 8.8-15.1%), PICA (6.8%; 95% CI: 1.5-14.5%), and AchoA (0.5%; 95% CI: 0.0-2.9%). The risk of branch occlusion-related complications was low (incidence rate <5%) for each of the six evaluated branches.

CONCLUSIONS

Acceptable outcomes were identified following treatment of IAs when FDSs were placed across each of the six studied cerebral arteries. Treatment decisions regarding FDS placement across branch arteries should be made with the risk of complications from branch occlusion in mind.

Correlation of Flow Diverter Malapposition at the Aneurysm Neck with Incomplete Aneurysm Occlusion in Patients with Small Intracranial Aneurysms: A Single-Center Experience

BACKGROUND AND PURPOSE

Flow diversion treatment repairs aneurysms by altering the hemodynamics of the aneurysmal sac and providing a scaffold for endothelial cell adhesion. The purpose of this study was to investigate the correlation of flow diverter (FD) malapposition at the aneurysm neck with incomplete occlusion of small intracranial aneurysms (IAs) and investigate other factors that are possibly related to incomplete occlusion.

MATERIALS AND METHODS

From January 2019 to June 2022, the clinical and imaging data for 153 patients (175 aneurysms) with unruptured small IAs treated with flow diversion were retrospectively analyzed. FD apposition at the aneurysm neck was evaluated by high-resolution conebeam CT (HR-CBCT), and the complete occlusion rate for aneurysms was judged according to the latest follow-up conventional angiography findings (≥6 months). Multivariate logistic regression analysis was used to determine factors associated with incomplete aneurysm occlusion.

RESULTS

In total, 159 FDs were implanted in 153 patients. HR-CBCT performed after the deployment revealed FD malapposition at the aneurysm neck in 18 cases. According to the latest follow-up angiograms (average: 9.47 ± 3.35 months), the complete aneurysm occlusion rate was 66.9%. The complete occlusion rates for incomplete and complete stent apposition at the neck were 38.9% (7/18) and 70.1% (110/157), respectively. The results of regression analysis showed that an aneurysm sac with branch vessels (OR, 2.937; P = .018), incomplete stent apposition at the aneurysm neck (OR, 3.561; P = .023), and a large aneurysm diameter (OR, 1.533; P = .028) were positive predictors of incomplete aneurysm occlusion.

CONCLUSIONS

An aneurysm sac with branch vessels, a large aneurysm diameter, and malapposition at the aneurysm neck significantly affect aneurysm repair after FD stent-only treatment for small IAs.

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.

No Delayed Ruptures on Long-Term Follow-Up of a Case Series of Persistently Filling Saccular Internal Carotid Artery Aneurysms After Flow Diversion With the Pipeline Embolization Device

BACKGROUND AND OBJECTIVES

Flow diversion of intracranial aneurysms results in high occlusion rates. However, 10% to 20% remain persistently filling at 1 year. Often, these are retreated, but benefits of retreatment are not well established. A better understanding of the long-term rupture risk of persistently filling aneurysms after flow diversion is needed.

METHODS

Our institutional database of 974 flow diversion cases was queried for persistently filling saccular aneurysms of the clinoidal, ophthalmic, and communicating segments of the internal carotid artery treated with the pipeline embolization device (PED, Medtronic). Persistent filling was defined as continued flow into the aneurysm on 1 year catheter angiogram. The clinical record was queried for retreatments and delayed ruptures. Clinical follow-up was required for at least 2 years.

RESULTS

Ninety-four persistent aneurysms were identified. The average untreated aneurysm size was 5.6 mm. A branch vessel originated separately in 55% of cases from the body of the aneurysm in 10.6% of cases and from the neck in 34% of cases. Eighteen percent of aneurysms demonstrated >95% filling at 1 year, and 61% were filling 5% to 95% of their original size. The mean follow-up time was 4.9 years, including 41 cases with >5 years. No retreatment was undertaken in 91.5% of aneurysms. There were no cases of delayed subarachnoid hemorrhage.

CONCLUSION

Among saccular internal carotid artery aneurysms treated with PED that demonstrated persistent aneurysm filling at 1 year, there were no instances of delayed rupture on long-term follow-up. These data suggest that observation may be appropriate for continued aneurysm filling at least in the first several years after PED placement.

Learning curve in pipeline embolization device: results from the pipeline embolization device in China post-market multicentre registry study

BACKGROUND

Intracranial aneurysms pose a significant health issue, affecting 3-5% of the adult population. The pipeline embolization device (PED) has emerged as a promising treatment for these lesions. This study aimed to investigate the impact of operator experience on complication and poor outcome rates, as well as the learning curve for PED.

METHODS

A total of 217 patients were consecutively enroled from four eligible centres and divided into three groups based on the number of procedures performed: group 1 (first 10 procedures), group 2 (11-20 procedures), and group 3(>20 procedures). Major complications include operation-related ischaemic or haemorrhagic events and mass effect deterioration. Poor outcome was defined as a modified Rankin Scale score greater than 2 at discharge. Cumulative summation (CUSUM) analysis was generated to assess the learning curve according to major complications and poor outcome.

RESULTS

The study found that major complications and poor outcomes occurred in 5.1% and 2.3% of cases, respectively. The rate of major complications decreased from 10.0% in group 1 to 2.9% in group 3 ( P =0.053), while the rate of poor outcomes decreased from 7.5% in group 1 to 0.7% in group 3 ( P =0.015). Multivariable regression analysis adjusted for covariates showed that operator experience was associated with a lower rate of poor outcomes ( P =0.034). CUSUM analysis demonstrated that the learning curve for avoiding major complications and poor outcomes required 27 (mean=13) and 40 (mean=20) cases, respectively.

CONCLUSIONS

These findings suggest that PED treatment requires a learning curve of 40 cases to achieve reproducibility regarding complications and functional results. Additionally, major complications and poor outcomes significantly decreases after the first 20 procedures. CUSUM analysis can serve as a useful tool for monitoring and assessing surgical performance.

Use of Tirofiban to Prevent Ischemic Events in Patients with CYP2C19 Loss-of-Function Alleles during Flow Diversion of Intracranial Aneurysm: A Multicenter Cohort Study

To analyze the effect of tirofiban on ischemic events in CYP2C19 loss-of-function (LOF) allele carriers during pipeline embolization device (PED) implantation. Demographic information, imaging data, ischemic complications, CYP2C19 genotyping, and platelet function test results were collected from patients with PED-treated intracranial aneurysms at three centers. Multivariate logistic regression was used to analyze risk factors for ischemic events. Patients were grouped according to LOF alleles and antiplatelet drugs, the baseline information of LOF allele carriers and non-carriers were compared, and the efficacy of tirofiban was analyzed by comparing the incidence of ischemic events in each group. In total, 278 patients were included in the study, 24 of whom had an ischemic event. 157 (56.5%) patients carried the LOF allele and were more likely to develop resistance to clopidogrel (P < 0.001) and hypertension (P = 0.010). Multivariate logistic regression analysis revealed that the independent risk factors for ischemic events were age of > 55 years (OR = 3.308, P = 0.028), LOF alleles (OR = 3.960, P = 0.036), and clopidogrel nonresponsiveness (OR = 3.301, P = 0.014). For LOF allele carriers, prophylactic use of tirofiban after PED implantation helped to reduce ischemic events (4.3% vs. 16.4%, P = 0.039). This study supports CYP2C19 genotyping before flow diversion because LOF alleles increase the risk of ischemic events. Prophylactic use of tirofiban may help reduce ischemic events in LOF allele carriers.

Comparison of pipeline classic and flex embolization devices in endovascular performance for intracranial aneurysms

To investigate the endovascular performance of the Pipeline Classic embolization device (PED Classic) and PED Flex device (PED Flex) in the treatment of intracranial aneurysms. Fifty-three patients with intracranial aneurysms treated with the PED Classic were retrospectively enrolled into the PED Classic group, and 118 patients with intracranial aneurysms treated with the PED Flex were enrolled into the PED Flex group. The Procedure time, contrast dosage, fluoroscopy time, and perioperative complications were analyzed. The success rate of the stenting procedure was 100% in both groups. In the PED Classic group, 58 PED Classic devices were implanted, and 26 aneurysms underwent coil embolization. In the PED Flex group, 126 PED Flex devices were implanted, and 35 aneurysms underwent concomitant coil embolization. The procedure time was significantly (P < .001) greater in the PED Classic (159.0 ± 42.0 minutes) than in the PED Flex (121.9 ± 4.0 minutes) group. The dosage of contrast agent (156.4 ± 39.4 vs 110.1 ± 38.5 mL) and the total fluoroscopic time (34.7 ± 5.7 minutes vs 22.8 ± 7.6 minutes) were significantly (P < .001) greater in the PED Classic than in the PED Flex group. Peri-procedural complications occurred in 5 (9.4%) patients in the PED Classic group and in 3 (2.5%) patients in the Flex group, without a statistically significant (P = .11) difference. The performance of the PED Flex device may be safer and easier than that of the PED Classic device in the treatment of intracranial aneurysms despite some serious complications which remain to be prevented.

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.

Safety and effect of pipeline flex embolization device for complex unruptured intracranial aneurysms

To investigate the safety and short-term effect of Pipeline Flex devices in the treatment of complex unruptured intracranial aneurysms, a retrospective study was performed for patients with complex unruptured intracranial aneurysms who were treated with the Pipeline Flex embolization device (PED Flex device) combined with or without coiling. The clinical, endovascular, and follow-up data were analyzed. One hundred and thirty-one patients with 159 complex unruptured cerebral aneurysms were treated with the PED Flex device, with 144 Flex devices deployed. Periprocedural complications occurred in four patients, resulting in the complication rate of 3.1%, including ischemic complications in three patients (2.3%) and hemorrhagic complication in one (0.8%). At discharge, the mRS was 0 in 101 (77.1%) patients, 1 in 25 (19.1%), 2 in four (3.1%), and 4 in one (0.8%), with the good prognosis rate (mRS 0-2) of 99.2%. Clinical follow-up was carried out in 87 (66.4%) patients 3-42 months after the procedure, with the mRS of 0 in 78 (89.7%), 1 in five (5.7%), 2 in three (3.4%), and 4 in one (1.1%). No significant (P = 0.16) difference existed in the mRS at discharge compared with that at clinical follow-up. Angiographic follow-up was performed in 61 (46.7%) patients with 80 (50.3%) aneurysms at 3-40 months, with the OKM grade of D in 57 (71.3%) aneurysms, C in eight (10%), and B in 15 (18.8%). Asymptomatic instent stenosis occurred in four patients (6.6%). In conclusion: The treatment of complex intracranial aneurysms with the Pipeline Flex embolization device may be safe and effective, with a high complete occlusion rate, a decreased complication rate, and a good prognosis rate at medium follow-up.

Could statin improve outcomes after pipeline embolization for intracranial aneurysms in a real-world setting?

Background

Several pharmacological pathways have revealed statin to have a positive role in patients with for intracranial aneurysms. However, prior studies regarding the association between statin use and patients' outcomes after pipeline embolization device (PED) treatment were not completely supportive.

Objectives

To investigate whether statin medication following PED treatment would improve the outcomes of intracranial aneurysm patients in a real-world setting.

Design

A retrospective multicenter cohort study.

Methods

Patients were selected from the PLUS registry study conducted from November 2014 to October 2019 across 14 centers in China. The population was divided into two groups: those who received statin medication after the PED treatment and those who did not receive statin medication after PED treatment. Study outcomes included angiographic evaluation of aneurysm occlusion, parent arteries stenosis, ischemic and hemorrhage complications, all-cause mortality, neurologic mortality, and functional outcome.

Results

1087 patients with 1168 intracranial aneurysms were eligible; 232 patients were in the statin user group and the other 855 were in the non-statin user group. For the statin user group versus the non-statin user group, no significant difference was found for the primary outcomes of complete occlusion of aneurysm (82.4% versus 84.2%; p = 0.697). Of the secondary outcomes, none had a significant difference including stenosis of parent arteries ≥ 50% (1.4% versus 2.3%; p = 0.739), total subarachnoid hemorrhage (0.9% versus 2.5%; p = 0.215), all-cause mortality (0.0% versus 1.9%; p = 0.204), neurologic mortality (0.0% versus 1.6%; p = 0.280), excellent (95.5% versus 97.2%; p = 0.877), and favorable (98.9% versus 98.4%; p = 0.933) functional outcomes. The total ischemic complication rate (9.0% versus 7.1%; p = 0.401) was higher but not significant in the statin user group. The propensity score-matched cohort showed similar results. Results of binary multivariable logistic regression analysis and propensity score-matched analysis both showed that statin usage was not independently associated with an increased rate of complete occlusion or any other secondary outcomes. Subgroup analysis found the same result in patients who did not use statin before the procedure.

Conclusion

Among patients with intracranial aneurysms, statin use after the PED treatment was not significantly associated with better angiographic and clinical outcomes. Well-designed studies are needed to further confirm this finding.

Methylprednisolone is related to lower incidence of postoperative bleeding after flow diverter treatment for unruptured intracranial aneurysm

Background and objectives

Regarding the anti-inflammatory effect, methylprednisolone is a candidate to prevent patients with unruptured intracranial aneurysms (UIAs) from postoperative bleeding (PB) after flow diverter (FD) treatment. This study aimed to investigate whether methylprednisolone is related to a lower incidence of PB after FD treatment for UIAs.

Methods

This study retrospectively reviewed UIA patients receiving FD treatment between October 2015 and July 2021. All patients were observed until 72  h after FD treatment. The patients receiving methylprednisolone (80  mg, bid, for at least 24 h) were considered as standard methylprednisolone treatment (SMT) users, otherwise as non-SMT users. The primary endpoint indicated the occurrence of PB, including subarachnoid hemorrhage, intracerebral hemorrhage, and ventricular bleeding, within 72 h after FD treatment. This study compared the incidence of PB between SMT users and non-SMT users and investigated the protective effect of SMT on PB after FD treatment using the Cox regression model. Finally, after controlling the potential factors related to PB, we performed subgroup analysis to further confirm the protective effect of SMT on PB.

Results

This study finally included 262 UIA patients receiving FD treatment. PB occurred in 11 patients (4.2%), and 116 patients (44.3%) received SMT postoperatively. The median time from the end of surgery to PB was 12.3 h (range: 0.5-48.0 h). SMT users had a lower incidence of PB comparing with non-SMT users (1/116, 0.9% vs. 10/146, 6.8%, respectively; p = 0.017). The multivariate Cox analysis demonstrated that SMT users (HR, 0.12 [95%CI, 0.02-0.94], p = 0.044) had a lower risk of PB postoperatively. After controlling the potential factors related to PB (i.e., gender, irregular shape, surgical methods [FD and FD + coil] and UIA sizes), the patients receiving SMT still had a lower cumulative incidence of PB, comparing with patients receiving non-SMT (all p < 0.05).

Conclusion

SMT was correlated with the lower incidence of PB for patients receiving FD treatment and may be a potential method to prevent PB after the FD treatment.

Effect and safety of Tubridge flow diverter in the treatment of unruptured intracranial aneurysms

The effect and safety of the Tubridge flow diverting device are unknown in the treatment of intracranial aneurysms after optimization of the device, improvement in the deployment of the device, and accumulation of experience of using the device. This retrospective one-center study was performed to investigate the clinical effect and safety of the Tubridge flow diverting device in the treatment of unruptured intracranial aneurysms. Twenty-three patients with 33 unruptured intracranial aneurysms which were treated with the Tubridge device were retrospectively enrolled. The clinical data, endovascular procedure, complications, and follow-up were analyzed. Twenty-seven Tubridge devices were deployed to treat the 33 aneurysms, and the deployment was failed in 1 case, resulting in the success stenting rate of 96.3%. In 5 (15.2%) aneurysms, coils were loosely packed. Peri-procedural complications occurred in 2 patients (8.7%), including 1 procedure-related complication in which the distal end of a Tubridge device herniated into the aneurysm cavity. In another case, weakness of left upper limb occurred on the second day post procedure, with instent thrombosis being suspected, which was recovered after medication. No other complications occurred. Twenty-three (100%) patients had clinical follow-up 6 months later, with the mRS of 0 in 21 patients, 1 in 1, and 2 in 1. Five (21.7%) patients with 11 aneurysms underwent digital subtraction angiography at 6-month follow-up, with 8 aneurysms being completely occluded (Raymond grade I) and 3 aneurysms still visible (Raymond grade III). The Tubridge flow diverter may be safe and effective in the treatment of unruptured intracranial aneurysms with low perioperative complications and good follow-up outcomes even though multi-center and prospective clinical studies with a large size sample are still needed to validate these results.

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.

Case report: Covered stent placement to treat delayed aneurysmal rupture after flow diverter-assisted coil embolization

INTRODUCTION

Flow diverter (FD) placement is widely accepted as a treatment for large saccular intracranial aneurysms. Delayed aneurysmal rupture (DAR) after FD placement is potentially catastrophic and difficult to treat. To our knowledge, using a Willis covered stent (WCS) to treat DAR after placement of a Pipeline Flex embolization device (PFED) combined with coiling has not been previously reported.

CASE PRESENTATION

A 49-year-old woman with an incidental asymptomatic large right supraclinoid internal carotid artery aneurysm was treated with PFED placement and adjunctive coiling. DAR causing subarachnoid hemorrhage occurred 11 hours after the procedure. Treatment using a WCS was successful and resulted in a favorable clinical outcome (modified Rankin scale score 2).

CONCLUSION

DAR after FD implantation requires isolation of the aneurysm from the cerebral circulation as soon as possible. WCS placement can achieve this immediately and occlude the aneurysm. We hope our case could provide new idea for similar cases in the future.

Stent-alone treatment of unruptured vertebral artery fusiform aneurysms: A comparison of flow diverter and conventional stents

Background

Treatment of vertebral artery fusiform aneurysms (VAFAs) is complex and controversial. This study aimed to compare the safety and efficacy between flow diverter and conventional stents in patients with VAFAs undergoing endovascular stent-alone treatment (SAT).

Methods

Thirty-six patients with 36 VAFAs who underwent SAT between January 2014 and December 2018 were retrospectively analyzed. Patient and aneurysm characteristics, procedural details, complications, and angiographic and clinical outcomes were compared between flow diverter stent patients (n = 22) and conventional stent patients (n = 14).

Results

More branches covered with stent were found in the conventional stent group (88.9 vs. 33.3%; p = 0.008). The number of stents placed was significantly higher in the conventional stent group (1.57 ± 0.76 vs. 1.09 ± 0.29; p = 0.016). The proportion of patients with significant or moderate stasis within the aneurysm immediately after stent placement was higher in the flow diverter stent group (95.5 vs. 57.1%; p = 0.004). The proportion of patients with complete obliteration or only a residual neck on follow-up angiography was significantly higher in the flow diverter stent group (86.3 vs 50.0%; p = 0.047). However, the incidence of parent artery stenosis or occlusion was also higher in the flow diverter stent group (27.3% vs. zero; p = 0.032). The rate of complications did not significantly differ between the groups.

Conclusions

SAT was safe and effective in patients with VAFAs. Flow diverter stents are associated with a significantly better complete occlusion rate than conventional stents; however, they are also associated with an increased risk of parent artery stenosis.

Thromboembolic Events Detected by Diffusion-Weighted Magnetic Resonance Imaging after Flow Diverter Treatment: The Impact of Procedure Time

BACKGROUND

Periprocedural thromboembolism is a serious complication of endovascular treatment for intracranial aneurysms. In addition to symptomatic ischemia, asymptomatic postprocedural diffusion-weighted image-positive lesions (DPLs) are considered important. However, few studies have reported significant risk factors associated with DPLs and symptomatic ischemic stroke after flow diverter (FD) treatment. This study aimed to investigate the frequency and risk factors associated with DPLs after FD treatment.

METHODS

Between November 2015 and December 2021, 84 patients harboring 85 untreated, unruptured intracranial aneurysms treated with FD were enrolled.

RESULTS

DPLs after FD treatment were confirmed in 74 patients (87.1%), among whom 69 (93.2%) were clinically asymptomatic. In the univariate analyses, age >55 years (P = 0.040), smoking (P = 0.023), preprocedural P2Y12 reaction unit value of >185 (P = 0.030), larger dome size of >9.3 mm (P = 0.013), and prolonged procedure time >80 minutes (P < 0.001) were significantly associated with postprocedural DPLs. In the multiple logistic regression model, only prolonged procedure time >80 minutes (odds ratio, 10.72; 95% confidence interval, 1.346-233.899; P = 0.023) was statistically significant. The mediator effect showed that the association between procedure time and the occurrence of DPLs was not significantly modified by any other factors, although only adjunctive coiling showed a tendency (P-value for interaction = 0.070).

CONCLUSIONS

Prolonged procedure time >80 minutes was the only identifiable factor related to postprocedural DPLs. Adjunctive coiling tended to mediate the effects of a prolonged procedure time on the occurrence of DPLs after FD treatment.

Pipeline flex embolization device for the treatment of large unruptured posterior circulation aneurysms: Single-center experience

PURPOSE

To investigate the safety and effect of the Pipeline Embolization Device (PED) Flex device in the treatment of large unruptured posterior circulation aneurysms in a single center.

MATERIALS AND METHODS

Patients with large unruptured posterior circulation aneurysms which were treated with the PED Flex device were enrolled. The clinical, endovascular and follow-up data were analyzed, and the O'Kelly-Marotta (OKM) grading system was used to assess the aneurysm occlusion status.

RESULTS

Fourteen patients with 14 large posterior circulation aneurysms who were treated with the PED Flex device were enrolled. The maximal diameter of aneurysm was 17.0 ± 3.9 mm. Fourteen PED Flex devices were deployed in 14 patients, with a technical success rate of 100%. All stents covered the aneurysm neck with good wall adherence and patent parent artery. Ten (71.4%) aneurysms were treated with a single PED Flex device each, and four (28.6%) patients experienced additional coiling. No neurological complications occurred in the periprocedural period. The mRS was 0 in eleven (78.6%) patients, 1 in two (14.3%), and 2 in one (7.1%) at discharge. All patients were followed up at 6-28 months (median 18), with an mRS score of 0 in all patients. Twelve (85.7%) patients experienced digital subtraction angiography 6-28 (median 18) months after the embolization procedure, and the OKM grade was D in nine (75%), C in two (16.7%), and B in one (8.3%).

CONCLUSION

The Pipeline Flex Embolization Device can be safely applied to treat large unruptured posterior circulation aneurysms with a high complete aneurysm occlusion rate at follow-up.

A novel score for evaluating cerebral aneurysms treated with flow diversion: 4F-flow diversion predictive score

Background and purpose

Although grading scales for angiography outcomes following cerebral aneurysm treatment with flow diversion have been published, physicians have not widely adopted these scales in practice. The aim of this study is to propose and validate a novel Flow diversion Predictive Score (4F-FPS) grading scale based on previously established scales that is simple and reliable.

Methods

We retrospectively analyzed consecutive patients who underwent endovascular treatment for cerebral aneurysms with flow diversion between January 2014 and September 2019. The included patients were randomly divided into the derivation and validation group in a 70/30 ratio, respectively. Aneurysms were classified as incomplete or complete occlusion based on final angiography outcomes. 4F-FPS was derived to predict aneurysm occlusion from multivariate logistic regression analyses in the derivation group and validated with previously published grading scales in the validation group.

Results

Overall, 662 patients [mean age, 53.8 years; 72.5% (480/662) female] with 662 aneurysms treated with the Pipeline^TM flow diverter were included [69.9% (463/662) derivation group, 30.1% (199/662) validation group]. The incidence of aneurysm occlusion was 82.7%. 4F-FPS demonstrated significant discrimination in 10-fold cross validation [mean receiver operating characteristic (ROC) area, 0.862 ± 0.055] and calibration (Cox & Snell R ², 0.251; Nagelkerke R ², 0.413) in the derivation group. The ROC area of 4F-FPS score in both the derivation and validation groups is the largest compared with previously published grading scales/scores (p < 0.05), which shows better sensitivity and specificity. The 4F-FPS score showed excellent prediction, discrimination, and calibration properties.

Conclusion

The 4F-FPS score is a simple and reliable tool to predict angiography outcome after flow diversion treatment. If widely adopted, it may provide a common language to be used in future reporting of flow diversion results for clinical trials and daily practice.

Clinical trial registration

http://www.clinicaltrials.gov. Unique identifier: NCT03831672.