Telescoping Flow Diverters for the Treatment of Brain Aneurysms: Indications and Outcome.

OBJECTIVE: Few studies have reported the impact of telescoping flow diverters (FDs) in intracranial aneurysm treatment. Our study compared aneurysms treated using telescoping FDs to those treated with a single FD and identified predictors of telescoping. METHODS: This was a single-center retrospective review of a prospectively maintained database of aneurysms treated with FDs between 2011 and 2023. All patients who were treated with FDs for intracranial aneurysms were included in the study. RESULTS: The study comprised 750 patients with 750 aneurysms treated using 871 FDs. The study cohort was divided into 85 patients requiring telescoping FDs and 655 who did not. Rates of hemorrhage (7.1% vs. 1.8%, P < 0.001), symptomatic stroke (5.9% vs. 2.6, P < 0.001), and asymptomatic stroke (1.2% vs. 0.8%, P < 0.001) were significantly higher in the telescoping cohorts. At final follow-up, the rate of nonocclusion (9.8% vs. 5.1%, P = 0.029) and the rate of complete occlusion (88.5% vs. 81.1%, P = 0.029) were significantly higher in the telescoping cohort. On multivariate analysis, fusiform morphology (odds ratio [OR]: 2.4, 95% confidence interval [CI] 1.0-5.0, P = 0.03), increasing aneurysm height (OR: 1.0, 95% CI 1.0-1.1, P= 0.034), and the use of the Pipeline Embolization Device FD (OR: 2.4, 95% CI 1.3-4.4, P = 0.005) were independent predictors of telescoping. CONCLUSIONS: Aneurysms with fusiform morphology, increasing aneurysm height and those that underwent flow diversion using Pipeline Embolization Device had higher odds for telescoping. Significantly higher rates of angiographic occlusion with the use of telescoping FD add to the literature on its efficacy in treating aneurysms of varying morphology.

Value of difference in diameters between Pipeline embolization device and parent artery in assessing aneurysm outcome.

OBJECTIVE: In vitro trials have demonstrated that oversized stents are associated with reduced metal coverage and increased porosity. However, the relationship between stent selection and aneurysm outcome is inconclusive, and determination of this was the authors' purpose in conducting this study. METHODS: This was a single-center retrospective study. Patients who underwent Pipeline embolization device treatment at the authors' center between January 1, 2018, and June 15, 2023, were enrolled. The authors constructed multiple logistic regression models and restricted cubic spline plots to examine the effect of the difference in diameters between the stent and parent artery (Dd) on aneurysm outcome. The authors also performed stratified analyses. Then, Dd was included in the logistic regression analysis as a categorical variable. The cutoff value for Dd was determined according to the principle of the maximum Youden's index. RESULTS: In total, 302 patients were included in this study. The median Dd was 0.52 mm. With a median follow-up time of 7 months, the aneurysm occlusion rate was 80.1%. The restricted cubic spline plots showed a decreasing aneurysm occlusion rate as Dd increased. After stratification by age and adjunctive embolization, the restricted cubic splines aligned with the results of the main analysis. Compared with the group with a smaller Dd (Dd < 0.3625 mm), the group with a larger Dd showed an OR of 0.439 (p = 0.026). Additionally, patients with diabetes mellitus (OR 0.306, p = 0.018), age ≥ 65 years (OR 0.968, p = 0.03), aneurysm incorporation with a branch (OR 0.253, p < 0.001), and aneurysm neck ≥ 4 mm (OR 0.872, p = 0.003) were independent predictors of aneurysm persistence, whereas Pipeline embolization device plus coiling (OR 4.949, p < 0.001) and smoking history (OR 5.86, p = 0.025) were predictors of aneurysm occlusion. CONCLUSIONS: The authors' retrospective analysis demonstrated that the aneurysm occlusion rate declined when Dd increased within a certain range. The authors suggested that Dd with an interval of -0.25 to 0.5 mm may be proper in clinical practice.

Pipeline embolization device placement under local versus general anesthesia: a propensity score-matched study.

OBJECTIVE: Pipeline embolization device (PED) placement for the treatment of intracranial aneurysms is safe and effective under general anesthesia (GA). However, GA is associated with certain risks, longer procedural time, and higher hospital cost. The authors aimed to compare clinical outcomes and hospital cost between GA and local anesthesia (LA) procedures in patients who underwent PED placement for intracranial aneurysm treatment. METHODS: This retrospective study analyzed the charts of 216 patients with 223 intracranial aneurysms treated using the PED from June 2022 to March 2023. Cases were grouped according to type of anesthesia administered (LA or GA). Propensity score matching (PSM) was used to balance the groups to minimize confounding bias. RESULTS: Eighty-four patients with 88 aneurysms were treated under LA, and 132 patients with 135 aneurysms were treated under GA. The complication rate and modified Rankin Scale score at 6 months were similar in both groups. Procedural time was significantly shorter with LA both before (87.47 ± 22.68 minutes vs 118.90 ± 46.80 minutes, p < 0.001) and after (84.75 ± 16.77 minutes vs 110.02 ± 38.56 minutes, p < 0.001) PSM. LA eliminates the need for postanesthesia recovery. Hospital cost was significantly lower in the LA group both before ($30,820.74 ± $3216.93 vs $32,846.62 ± $4731.50, p = 0.001) and after ($30,127.83 ± $2763.12 vs $33,874.41 ± $3163.56, p = 0.002) PSM. CONCLUSIONS: PED placement under LA can achieve satisfactory outcomes similar to those of PED placement under GA; however, the use of LA reduces procedural time and hospital cost.

Clopidogrel Hyperresponsiveness and Hemorrhagic Complications Using On-Label Clopidogrel Dosing after Pipeline Embolization.

Introduction: Clopidogrel hyperresponsiveness is a timely topic, with wide ranging reports of hemorrhagic complications, using various clopidogrel dosing strategies following neuroendovascular procedures. This study serves to investigate hemorrhagic complications using standard clopidogrel doses and timing of these complications in relation to the procedure. Materials and Methods: Retrospective cohort of consecutive adult patients undergoing flow diversion with Pipeline Embolization Device (PED) at an academic medical center, receiving on-label clopidogrel doses. Patients with clopidogrel hyperresponsiveness (VerifyNowTM P2Y12 reaction unit (PRU) ≤ 70) were compared to those who were normoresponsive. The primary outcome is the rate of hemorrhagic complications between groups. Results: Of 148 included patients, 54 (36.5%) were identified as clopidogrel hyperresponsive (PRU ≤ 70) and 94 (63.5%) as clopidogrel normoresponsive (PRU 71 - 194). There were no hemorrhagic complications observed in patients who were clopidogrel hyperresponsive, with 5 occurring in patients who were normoresponsive (P = 0.09). Three (60%) of the hemorrhages were intracranial with most occurring intra-procedure or within the first week of the procedure. Age > 60 years was the only candidate predictor for hemorrhagic complications (P = 0.004). Conclusion: Our findings are contradictory, with lower hemorrhagic complications in clopidogrel hyperresponders than prior literature, and most occurring intra-op or in the immediate acute post-op phase.

The aneurysm occlusion and recurrence of posterior communicating artery aneurysms following the treatment with the pipeline embolization device.

Despite advancements in treatment modalities such as flow diverters, the optimal management of posterior communicating artery (PComA) aneurysms remains uncertain. While PComA aneurysms treated with the Pipeline Embolization Device (PED) has been reported, the characteristics and progression of incomplete occluded aneurysms remain unclear. Therefore, our study aims to investigate the occlusion status and recurrence rates of PComA aneurysms treated with PED. A retrospective review of consecutive PComA aneurysm patients treated with PED was conducted between January 2015 and December 2020. Only patients with radiological follow-up were included. PComA aneurysms were categorized into incomplete occlusion and complete occlusion group. The primary outcomes included the characteristics of incomplete occlusion at the follow-up angiography. Among 121 PComA aneurysms treated with PED at our institution, 80 aneurysms were eligible in our study. During the follow-up period, 19 (23.8%) aneurysms demonstrated incomplete occlusion. Notably, there were no instances of recurrence among the 80 followed-up cases. Baseline characteristics of patients and aneurysms were comparable between the groups with complete and incomplete occlusion. However, the incomplete occlusion group showed a lower rate of assisted coils embolization (21.2% vs. 55.7%, P = 0.017) and shorter median operative time (91.0 vs. 145.5 min, P = 0.039). Differences in functional outcomes, complications, and PComA occlusion status between the groups were not significant. Multivariate analysis revealed the use of coils was associated with lower odds of incomplete PComA aneurysm occlusion (OR 0.01, 95% CI 0.001-0.12; P = 0.001), while aneurysm size was associated with higher odds of incomplete occlusion (OR 1.25, 95% CI 1.10-1.46; P = 0.002). The treatment of PED for PComA aneurysm demonstrated favorable outcomes, with an acceptable rate of incomplete occlusion and no instances of recurrence observed. However, further research is needed to explore the optimal procedural strategy for large-sized PComA aneurysms.

Comparison of pipeline embolization device and flow redirection endoluminal device in the treatment of intracranial aneurysms: A systematic review and meta-analysis.

BACKGROUND: Advancements in flow diversion technology have revolutionized the treatment of intracranial aneurysms. The pipeline embolization device (PED) and the flow redirection endoluminal device (FRED) have emerged as prominent tools in this field. This study aims to compare the safety and efficacy profiles of PED and FRED in the treatment of intracranial aneurysms. METHODS: Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, a comprehensive literature search was conducted across PubMed, Web of Science, and Scopus databases. Studies comparing PED and FRED were included and data extraction focused on study characteristics, patient demographics, and clinical and radiological outcomes. Primary outcomes were favorable outcomes, described as modified Rankin scale (mRS) 0-2 score, and complete/near-complete occlusion, while secondary outcomes included retreatment rate and thromboembolic and hemorrhagic complications. RESULTS: Five studies, comprising 1238 patients, were included. No significant differences were found between PED and FRED in terms of complete occlusion at 6 months and 1 year, complete/near-complete occlusion at the last follow up, retreatment rates, and thromboembolic, in-stent thrombosis and hemorrhagic complications. However, FRED was significantly associated with higher favorable outcomes compared to PED (odds ratio: 0.37; confidence interval: 0.17 to 0.81; p = 0.01). CONCLUSION: This study showed that both PED and FRED had comparable rates of complete occlusion, retreatment and complications, and FRED also demonstrated a higher likelihood of achieving favorable outcomes. The study underscores the need for further research with larger cohorts and longer follow up to consolidate these findings.

Pipeline Embolization Device and Flow Re-Direction Endoluminal Device for Intracranial Aneurysms: A Comparative Systematic Review and Meta-Analysis Study.

BACKGROUND: When it comes to intracranial aneurysms, the quest for more effective treatments is ongoing. Flow diversion represents a growing advancement in this field. This review seeks to compare 2 variants of the endovascular flow diversion method: the Flow Re-Direction Endoluminal Device (FRED) and the Pipeline Embolization Device (PED). METHODS: A systematic review was conducted according to the PRISMA guideline using PubMed, Scopus, Web of Science, and Embase, using appropriate terms to compare PED and FRED in double-arm studies from conception until October 8th, 2023. RESULTS: The meta-analysis encompassed 1769 patients, with a predominance of females (75.5%), among whom 973 patients underwent FRED procedures, while 651 received PED interventions. At 6 months, complete occlusion rates were 0.62 for FRED and 0.68 for PED (P = 0.68). At 1 year and the last follow-up, no significant differences were observed between FRED and PED, respectively. Adequate occlusion rates were similar between FRED and PED (0.82 vs. 0.79, P = 0.68). FRED showed a statistically significant higher rate of good mRS scores at follow-up (1.00 vs. 0.97, P = 0.03). Hemorrhage and re-treatment rates were higher in PED (P < 0.01) without considering the rupture status of the aneurysms due to the lack of data. CONCLUSIONS: This meta-analysis suggests comparable efficacy but different safety profiles between FRED and PED in treating intracranial aneurysms. FRED demonstrated a higher rate of good modified Rankin scores, while PED showed increased hemorrhage and re-treatment rates. Understanding these differences is crucial for informed decision-making in clinical practice.

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.

Retrosigmoid Craniectomy for Clip Ligation of Flow-Diverted Posterior Inferior Cerebellar Artery Aneurysm.

Flow diversion (FD) has revolutionized the treatment of cerebral aneurysms. Since the introduction of the Pipeline Embolization Device, there has been a significant shift in the management of cerebral aneurysms, with increasing emphasis being placed on use of endoluminal reconstruction as a means of long-term, durable treatment of aneurysms. Increasingly, FD stents are being used as primary treatment for aneurysms, including those that present with subarachnoid hemorrhage.1 Improper use of FD stents, however, may create havoc, as access to the aneurysm sac is blocked with the placement of these devices. Aneurysms that are incompletely treated with FD may continue to grow and rupture. The inability to use coils or endosaccular devices for treatment of these aneurysms means the only options for treatment are placement of additional FD devices, deconstructive strategies with or without bypass, or microsurgical clipping,2 thereby making an aneurysm that may have been straightforward to treat with another strategy a complex lesion to treat with the presence of the FD stent. Although deconstructive techniques can be used for treatment of failed aneurysm occlusion with flow diversion, where possible, surgical clipping can result in the simplest, most durable solution. Herein we present (Video 1) a case of a patient with a posterior inferior cerebellar artery aneurysm treated previously with FD using a single pipeline embolization device without aneurysm occlusion over 1 year of follow-up who was treated with retrosigmoid craniotomy and clipping of aneurysm. Nuances of the approach selection, clipping of the aneurysm, and preservation of the stent are discussed.

Treatment of an Intracranial Fusiform Vertebral Aneurysm Using the MVP® Micro Vascular Plug System as an Adjunct to Pipeline(TM) Embolization: Technical Case Instruction.

Fusiform and dolichoectatic aneurysms pose unique challenges in treatment, often requiring alternative approaches compared to saccular aneurysms. Microsurgical options like clipping or a bypass can be difficult, leading to the advancement of endovascular techniques. Flow-diverting stents and vessel sacrifice with detachable coils have shown efficacy in reconstruction. The MVP® Micro Vascular Plug System (Medtronic, Minneapolis, Minnesota, USA) offers a resheathable plug for vessel occlusion through electrolytic detachment. This case report illustrates the supplementary application of MVP® subsequent to flow diverter (FD) stenting, resulting in the effective endovascular management of a fusiform aneurysm affecting both vertebral arteries (VA), following unsuccessful coil vessel sacrifice treatment. A 61-year-old female presented with an unruptured fusiform aneurysm in the bilateral vertebral arteries (VAs). Treatment included a flow diverter in the right VA and vessel sacrifice in the left VA using Onyx-18 and coils. Despite initial success, left V4 segment recanalization occurred. Endovascular treatment, deploying two devices and additional coils using the MVP®, halted the flow. Follow-up showed left VA occlusion and reconstruction of the treated right VA, with the patient being discharged without deficits. This case demonstrates a unique approach using MVP® alongside a flow diverter (a PipelineTM Embolization Device (PED), Medtronic) for the treatment of a V4 segment fusiform aneurysm. This innovative technique is an alternative when conventional coil embolization for vessel sacrifice fails. The MVP®'s ease of use and precise delivery render it a feasible and efficacious alternative for treating complex aneurysms.