Long-term results of flow diversion in the treatment of intracranial aneurysms: a retrospective data analysis of a single center

Braid stability after flow diverter treatment of intracranial aneurysms: a systematic review and meta-analysis

BACKGROUND

The aim of this study was to evaluate the overall rates of braid changes associated with flow diverter (FD) treatment for intracranial aneurysms (IAs). Additionally, we sought to provide an overview of the currently reported definitions related to these complications.

METHODS

A systematic search was conducted from the inception of relevant literature up to April 2023, encompassing six databases. The included studies focused on patients with IAs treated with FDs. We considered four main outcome measures as FD braid changes: (1) fish-mouthing, (2) device braid narrowing, (3) device braid collapsing, and (4) device braid deformation. The data from these studies were pooled using a random-effects model.

RESULTS

A total of 48 studies involving 3572 patients were included in the analysis. Among them, 14 studies (39%) provided definitions for fish-mouthing. However, none of the included studies offered specific definitions for device braid narrowing, collapsing, or deformation, despite reporting rates for these complications in six, five, and three studies, respectively. The pooled rates for braid changes were as follows: 3% (95% CI 2% to 4%, I2=27%) for fish-mouthing, 7% (95% CI 2% to 20%, I2=85%) for narrowing, 1% (95% CI 0% to 3%, I2=0%) for collapsing, and 1% (95% CI 1% to 4%, I2=0%) for deformation.

CONCLUSION

The findings of this study suggest that FD treatment for IAs generally exhibits low rates of fish-mouthing, device braid narrowing, collapsing, and deformation. However, the lack of standardized definitions hinders the ability to compare device outcomes objectively, emphasizing the need for uniform definitions for FD braid changes in future prospective studies on FD.

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.

Design and Analysis of a Biodegradable Polycaprolactone Flow Diverting Stent for Brain Aneurysms

The flow diverting stent (FDS) has become a promising endovascular device for the treatment of aneurysms. This research presents a novel biodegradable and non-braided Polycaprolactone (PCL) FDS. The PCL FDS was designed and developed using an in-house fabrication unit and coated on two ends with BaSO₄ for angiographic visibility. The mechanical flexibility and quality of FDS surfaces were examined with the UniVert testing machine, scanning electron microscope (SEM), and 3D profilometer. Human umbilical vein endothelial cell (HUVEC) adhesion, proliferation, and cell morphology studies on PCL FDS were performed. The cytotoxicity and NO production by HUVECs with PCL FDS were also conducted. The longitudinal tensile, radial, and bending flexibility were found to be 1.20 ± 0.19 N/mm, 0.56 ± 0.11 N/mm, and 0.34 ± 0.03 N/mm, respectively. The FDS was returned to the original shape and diameter after repeated compression and bending without compromising mechanical integrity. Results also showed that the proliferation and adhesion of HUVECs on the FDS surface increased over time compared to control without FDS. Lactate dehydrogenase (LDH) release and NO production showed that PCL FDS were non-toxic and satisfactory. Cell morphology studies showed that HUVECs were elongated to cover the FD surface and developed an endothelial monolayer. This study is a step forward toward the development and clinical use of biodegradable flow diverting stents for endovascular treatment of the aneurysm.

Transient third cranial nerve palsy after pipeline shield treatment of a ruptured anterior cerebral artery dissecting aneurysm: Case report

Background:

Intracranial dissecting aneurysms (IDAs) are rare vascular lesions usually arising from the posterior circulation. The anterior cerebral artery (ACA) is an unusual location for this pathology. Even rarer is the occurrence of a transient de novo third cranial nerve (CN) palsy after flow-diverting device (FDD) treatment of an ACA dissecting aneurysm.

Case Description:

A middle-aged man with a prior history of hypertension was admitted to our emergency department with severe headache and loss of consciousness after sexual intercourse. Imaging revealed a subarachnoid hemorrhage with stenosis of the left A1 segment of the ACA. Cerebral digital subtraction angiography confirmed a dissecting aneurysm of the left A1 segment. The aneurysm was treated with an FDD (Pipeline Shield). Transient isolated incomplete third CN palsy was documented 12 h after treatment. No evidence of ischemic or hemorrhagic strokes was found. The condition improved after a few days of empiric steroid treatment.

Conclusion:

An FDD is a suitable alternative for the treatment of a ruptured IDA of the anterior circulation. Some infrequent complications associated with the device, such as de novo cranial neuropathies, are yet to be studied.

Outcome of Flow Diverters with Surface Modifications in Treatment of Cerebral Aneurysms: Systematic Review and Meta-analysis

BACKGROUND

Newer flow diverters are enhanced with antithrombogenic surface modifications like the Pipeline Embolization Device with Shield Technology and the Derivo Embolization Device and are purported to facilitate deployment and reduce ischemic events.

PURPOSE

Our aim was to review the safety and efficacy of surface-modified flow diverters in treating patients with cerebral aneurysms.

DATA SOURCES

We used Preferred Reporting Items for Systematic Reviews and Meta-Analyses-compliant systematic review and meta-analysis covering 3 major data bases and gray literature between 2014 and 2019.

STUDY SELECTION

Two reviewers independently reviewed human studies of surface-modified flow diverters for eligibility based on predetermined criteria.

DATA ANALYSIS

The random effects model and Freeman-Tukey arcsine transformation were used to pool efficacy outcomes (technical success, aneurysm occlusion at 6 and 12 months) and safety outcomes (mortality, morbidity, all ischemia, and serious ischemia). Subgroup analysis was performed to compare outcomes between 2 different flow diverters.

DATA SYNTHESIS

Eight single-arm case series involving 911 patients and 1060 aneurysms were included. The median follow-up was 8.24 months. Pooled estimate for technical success was 99.6%, while the aneurysm occlusion at 6 and 12 months were 80.5%, and 85.6%, respectively. Pooled estimates for mortality, morbidity, total ischemia, and serious ischemia rates were 0.7%, 6.0%, 6.7%, and 1.8%, respectively. Most studies were of good quality, and no significant heterogeneity was observed.

LIMITATIONS

Limitations include a retrospective, observational design in some studies; heterogeneous and underreported antiplatelet therapy; and potential performance and ecologic bias.

CONCLUSIONS

Early-to-midterm safety and efficacy for surface-modified flow diverters appear comparable with older devices, especially for small, unruptured anterior circulation aneurysms. Long-term clinical data are required to further corroborate these results.

Flow Diversion for Treatment of Acutely Ruptured Intracranial Aneurysms : A Single Center Experience from 45 Consecutive Cases

BACKGROUND

Reports about the use of flow diverter stents (FDS) in the acute setting of subarachnoid hemorrhage (SAH) are limited. This article presents a single center experiences based on 45 consecutive cases with emphasis on complication rates and clinical and radiologic outcomes.

METHODS

A prospectively maintained database of all cases treated with FDS as a stand-alone or adjunct device was retrospectively reviewed. All patients treated within 30 days of SAH were included. Records were made of clinical presentation, details of endovascular treatment, procedural complications, clinical outcome, and degree of occlusion on follow-up.

RESULTS

In this study 45 patients (48.9% females; mean age 58.8 ± 12.4 years) were included. Flow diversion was performed after a median of 4 days. The procedural complication rate was 13.3% resulting in 2.2% permanent morbidities and 4.4% mortalities. No major hemorrhagic complications related to antiplatelet therapy were recorded. Immediate complete occlusion was achieved in 13.3%. Among survivors, complete occlusion was achieved in 94.6%. Excellent clinical outcome was recorded in 68.9% and 81.6% of the total population and survivors, respectively. There were no records of rebleeding from the target lesions.

CONCLUSION

Flow diversion is an attractive alternative strategy for management of acutely ruptured aneurysms with high rates of delayed complete occlusion and acceptable complication rates.

[Treatment of intracranial aneurysms with flow diverters]

CLINICAL ISSUE

The clinical picture of a subarachnoid haemorrhage (SAH) is associated with a high morbidity and mortality, due to the associated complications. Therefore, both unruptured and ruptured aneurysms are to be treated based on an individual and interdisciplinary treatment concept. Several endovascular procedures are already available for the treatment of intracranial aneurysms. A more recent concept is the treatment with vessel-reconstructive stents so-called flow diverters.

PRACTICAL RECOMMENDATIONS

Due to the continuous development and revision of flow diverters, the initial complication rates have been significantly reduced, which now effectively and efficiently justifies their clinical use. After careful patient selection and risk-benefit assessment, the implantation of a flow diverter can also be considered for the treatment of ruptured aneurysms and is often the only therapy option in such situations.