Diffusion-weighted imaging lesions after intracranial aneurysm treatment with Pipeline Flex and Pipeline Flex with Shield technology: a retrospective cohort analysis

Comparison of Thromboembolic Events Between Pipeline Embolization Device (PED) Shield and PED/PED Flex: A Propensity Score-Matched Analysis

BACKGROUND AND OBJECTIVES

The pipeline embolization device (PED) Flex with Shield technology is a third-generation flow diverter used for intracranial aneurysm treatment designed to decrease thrombogenicity through a phosphorylcholine coating. Herein, we aim to compare the rate of thromboembolic events in PED with Shield technology and PED without it through propensity score matching.

METHODS

We conducted a retrospective analysis of aneurysms treated with PED first-generation/PED Flex and PED with Shield between 2013 and 2023 at a single academic institution. Patients were matched through propensity score by controlling for confounding factors including age, smoking history, diabetes, previous subarachnoid hemorrhage, modified Rankin Scale pretreatment, location, aneurysm size, previous treatment, and clopidogrel or aspirin resistance. After matching, we evaluated for periprocedural and postoperative thromboembolic events. Data analysis was performed using Stata 14.

RESULTS

A total of 543 patients with 707 aneurysms treated in 605 procedures were included in the analysis. From these, 156 aneurysms were treated with PED with Shield (22.07%) and 551 (77.93%) without Shield technology. Propensity score matching resulted in 84 matched pairs. The rate of thromboembolic events was 3.57% for PED Shield and 10.71% for PED first-generation/PED Flex ( P = .07), while retreatment rates were 2.38% for PED Shield and 8.32% for PED Flex ( P = .09). Complete occlusion at first ( P = .41) and last imaging follow-up ( P = .71), in-stent stenosis ( P = .95), hemorrhagic complications ( P = .31), and functional outcomes ( P = .66) were comparable for both groups.

CONCLUSION

This is the first study in the literature performing a propensity scored-matched analysis comparing PED with PED with Shield technology. Our study suggests a trend toward lower thromboembolic events for PED Shield, even after controlling for aspirin and clopidogrel resistance, and a trend toward lower aneurysm retreatment rates with PED Shield, without reaching statistical significance.

FRED X flow diverter for the treatment of intracranial aneurysms: Two-center experience and mini-review of the literature

OBJECTIVE

The flow re-direction endoluminal device (FRED) is a safe and effective treatment option for intracranial aneurysms. The novel FRED X features an antithrombotic surface coating ("X Technology") on an otherwise unmodified stent design. This two-center study evaluates the clinical safety and efficacy of FRED X and compares it to the literature.

METHODS

Consecutive patients treated between 2020 and 2023 were retrospectively reviewed for aneurysm characteristics, procedural details and complications, and angiographic outcomes. A mini-review of the literature for FRED X clinical trials was performed and results were pooled using a random effects model.

RESULTS

Thirty-four patients (mean age 56 years) were treated for 34 aneurysms. The mean aneurysm size was 7.7 ± 5.0 mm, 7 (21%) were ruptured, 6 (18%) were recurrent after previous treatment, 11 (32.3%) were located in the posterior circulation, and 4 (12.5%) had non-saccular morphology. All procedures were technically successful and no balloon angioplasty was required. There was 1 (2.9%) symptomatic complication (a transient ischemic attack) and no procedural morbidity or mortality. Technical asymptomatic events included 1 procedural stent occlusion that was reopened with thrombectomy and 3 cases of vasospasm. Complete and adequate occlusion rates were 68% (19/28) and 89% (25/28) at a mean follow-up time of 6 months, respectively. The results of this study are comparable to previous FRED X studies.

CONCLUSIONS

The results demonstrate a high feasibility and procedural safety of the FRED X with adequate mid-term occlusion rates. Long-term and comparative studies are needed to evaluate the full potential of the FRED X.

A Study on the Efficacy and Safety of Pipeline Shield Stents and Nonmodified Surface Flow-Diverting Stents in Patients with Intracranial Aneurysms

BACKGROUND

Few studies have compared the Pipeline Shield stents with previous generations of flow-diverting stents (FDSs) for the treatment of unruptured intracranial aneurysms. This study aimed to evaluate the efficacy and safety of Pipeline Shield stents and FDSs without modified surfaces.

METHODS

The present evaluation is a retrospective cohort study of patients endovascularly treated with Pipeline Shield stents or FDSs without modified surfaces for unruptured intracranial aneurysms between January 2014 and June 2022. The data analyzed were obtained from the anonymized database of our institution's interventional radiology service.

RESULTS

A total of 147 patients with 155 unruptured intracranial aneurysms were included. Of the 155 aneurysms, 96 were treated with Pipeline Shield stents and 59 with FDSs without modified surfaces. The aneurysms treated with Pipeline Shield stents had higher 6-month (O'Kelly-Marotta [OKM] D; 87.5% vs. 71.4%; P = 0.025) and 1-year (OKM D; 82.5% vs. 63.0%; P = 0.047) occlusion rates than the aneurysms treated using FDSs without modified surfaces. No differences between the devices were found at the 1-year follow-up in the incidence of ischemic stroke (P = 0.939) or hemorrhagic complications (P = 0.559).

CONCLUSIONS

Pipeline Shield stents demonstrated superior complete occlusion rates (OKM D) at both the 6-month and the 1-year follow-up assessments compared with nonmodified surface FDSs. No significant differences were found in the safety profiles between the 2 types of stents with regard to thromboembolic complications and ischemic events. Further research with larger study populations is necessary to validate these findings.

Flow diverter stents for endovascular treatment of aneurysms: a comparative study of efficacy and safety between FREDX and FRED

BACKGROUND

The FRED X flow diverter (FREDX), as the second generation in the FRED series, aims to improve the treatment of cerebral aneurysms. This study compares the efficacy and safety of FREDX with its predecessor, FRED.

METHODS

This prospective registry included patients treated with FRED and FREDX devices. Efficacy was assessed using digital subtraction angiography with 3D volumetric reconstruction at immediate and 1 year follow-ups. Safety was evaluated by recording complications, analyzed through univariate contrasts, generalized mixed models, and Bayesian network analyses.

RESULTS

We treated 287 patients with 385 aneurysms, with 77.9% receiving FRED and 22.1% FREDX. The median age was 55 years (IQR 47-65) and 78.4% were women. The FREDX group showed a higher prevalence of saccular-like aneurysms (70.6% vs 52.7%, P=0.012) and a higher rate of complete occlusion compared with FRED interventions (79.4% vs 59.3%, P=0.022). After adjusting for confounders, these differences represented a 3.04-fold increased likelihood (95% CI 1.44 to 6.41, P=0.003) of achieving complete occlusion at 1 year with FREDX interventions. Regarding safety, two (3.5%) complications (both non-symptomatic) were observed in the FREDX group and 23 (10.4%) in the FRED group (P=0.166). Bayesian network analysis suggested a trend towards fewer complications for FREDX, with a median reduction of 5.5% in the posterior distribution of the prevalence of complications compared with FRED interventions.

CONCLUSIONS

The FREDX device shows improved complete occlusion rates at 1 year compared with the FRED device while maintaining a favourable safety profile, indicating its potential advantage in the treatment of cerebral aneurysms.