Endovascular Treatment of Posterior Circulation Saccular Aneurysms With the p64 Flow Modulation Device: Mid-and Long-Term Results in 54 Aneurysms From a Single Center

Evaluation of an Antithrombotic Surface-Coated Flow Diverter in a Rabbit Model without Dual Antiplatelet Drugs

OBJECTIVE

Flow diverters (FDs) carry the risk of thromboembolic complications associated with the device and bleeding complications associated with dual antiplatelet therapy. We hypothesize that an antithrombotic surface-coated FD (ASCFD) would have less acute thrombus formation and better endothelialization on the device surface compared with uncoated FD.

METHODS

A ASCFD was developed. Acute clot formation and chronic endothelialization over the device were assessed in 8 rabbit models compared with its prototype FD (PFD) at 2 hours and 1 month by scanning electron microscopy (SEM) and histologic images. Nonparametric score data, including thrombus, injury, endothelialization, adventitial inflammation, intramural bleeding, and intimal hyperplasia were compared between ASCFD and PFD using the Kendall coefficient of rank correlation.

RESULTS

Parent artery and branch artery were patent on digital subtraction angiography in 8 ASCFDs and 6 PFDs. There was 1 intrastent thrombosis in PFDs at 2 hours and 1 intrastent stenosis in PFDs at 1 month. SEM at 2 hours showed that a large number of blood cells adhered to the surface of all 4 PFDs, and no blood cells were found on the surface of all 4 ASCFDs. At SEM and histologic analysis of 1 month, there was less inflammation (Kendall τ-B -0.818; P ＝ 0.022), less vessel wall injury (Kendall τ-B = -0.764; P ＝ 0.032), and better endothelialization (Kendall τ-B = 0.818; P ＝ 0.022) in ASCFDs.

CONCLUSIONS

In the rabbit model, the ASCFD is associated with less thrombus formation at the acute stage, less inflammation, less vessel injury, and better endothelialization on the device surface compared with the PFD.

Innovations in intracranial aneurysm treatment: a pilot study on the Choydar flow diverter

Background

The flow diverter (FD) has emerged as a promising treatment option for intracranial aneurysms. Recently, a novel flow-diverting stent, the Choydar FD device, has been developed within our nation.

Objective

To introduce the newly developed Choydar FD device and present our preliminary clinical experience with its application in the treatment of intracranial aneurysms.

Methods

A total of 23 patients with 23 unruptured intracranial aneurysms, comprising 20 (87.0%) aneurysms located at the internal carotid artery and 3 (13.0%) at the vertebral artery, were treated with the Choydar FD device between December 2021 and April 2022. Patient baseline data, clinical and angiographic outcomes were collected and analyzed.

Results

The Choydar FD device was successfully deployed in all patients (100%), with 18 aneurysms (78.3%) additionally treated with coils. One patient experienced an ischemic event with sensory disturbance during the perioperative period. At the 1-year follow-up, all patients demonstrated good clinical outcomes. Of the 23 aneurysms with available angiographic follow-up, 22 (95.7%) achieved complete occlusion, and one patient exhibited in-stent stenosis without neurological deficits.

Conclusion

The initial clinical results of the Choydar FD device are encouraging, and it appears to be a useful option for treating intracranial aneurysms with acceptable efficacy and safety. Future studies with larger sample sizes and longer follow-up durations are warranted to validate these findings.

Phenox HPC and Phenox flow modulation devices for the endovascular treatment of intracranial aneurysms: a systematic review and meta-analysis

BACKGROUND

Surface-modified flow diverters are increasingly used in clinical settings. However, their safety profiles and additional benefits over non-coated devices still need to be explored. In this meta-analysis, we aimed to investigate and compare the clinical outcomes of the uncoated Phenox and coated Phenox HPC flow diverters.

METHODS

A systematic literature review was performed using PubMed, Scopus, Embase, and Web of Science databases. Collected data were pooled and corresponding 95% confidence intervals (CI) were calculated. Outcomes of interest included aneurysm occlusion (>6 months) and complication rates. Additionally, the safety outcomes of prophylactic single (SAPT) and dual antiplatelet treatment (DAPT) approaches were compared for patients treated with coated Phenox HPC flow diverters.

RESULTS

We included 17 studies with 1238 patients. The overall complete occlusion rates were 80% (95% CI 74.01% to 86.56%) for Phenox HPC and 71.3% (95% CI 59.71% to 85.20%) for non-coated Phenox flow diverters (p=0.24). Ischemic complication rates were 7.3% (95% CI 4.6% to 11.39%) with the Phenox HPC and 5.3% (95% CI 4.07% to 6.91%) with the Phenox (p=0.24). For patients treated with Phenox HPC, the SAPT (5.5%; 95% CI 2.83% to 10.85%) and DAPT (7.1%; 95% CI 1.23% to 41.45%) approaches resulted in comparable ischemic complication rates (p=0.79). The DAPT group (4.8%; 95% CI 1.46% to 16.24%) had higher hemorrhagic complication rates than the SAPT group (1.7%; 95% CI 0.52% to 6.09%), but the difference was not statistically significant for patients treated with Phenox HPC (p=0.25).

CONCLUSIONS

Our findings indicate that Phenox HPC is equally as safe and effective as non-coated Phenox devices. Additionally, our results suggest that prasugrel monotherapy might effectively prevent ischemic complications in patients treated with Phenox HPC flow diverters.

Intra-arterial microguidewire electrocoagulation to treat intracranial vascular diseases

OBJECTIVE

To investigate the therapeutic effect of intra-arterial microguidewire electrocoagulation on intracranial vascular diseases.

METHODS

Data from 10 patients with cerebral aneurysms between May 2018 and September 2022 were analysed. Patients were treated with endovascular coil embolisation and microguidewire electrocoagulation. XperCT scans were conducted to identify new intracranial haemorrhage, infarction and hydrocephalus. Follow-up examinations were conducted 1, 3, 6 and 12 months after discharge.

RESULTS

After the patients received electrocoagulation for different durations, Raymond Grade 1 embolisation was achieved in all 10 patients. No complications, such as haemorrhage, infarction or hydrocephalus, were found during or after surgery. Ten patients were followed up for 6-12 months, and none had any symptoms or new neurological dysfunction 1 month after their operation. Among them, nine were followed up for 12 months, and digital subtraction angiography showed no recurrence of aneurysms or occlusion of parent arteries.

CONCLUSION

Intra-arterial microguidewire electrocoagulation can be used as a supplementary treatment for cerebral aneurysms. In cases of incomplete lesion embolisation and cases where tamponade treatment cannot continue, immediate thrombosis may occur. Thus, intra-arterial microguidewire electrocoagulation can help achieve patients' treatment goals.

Long-term outcomes of flow diversion for unruptured intracranial aneurysms: a systematic review and meta-analysis

BACKGROUND

Flow diverters have been widely used in clinical practice for more than a decade. However, most outcome data are limited to 1 year timepoints. This study aims to offer meta-analysis data on long-term (>1 year) safety and effectiveness results for patients with aneurysms treated with flow diverters.

METHODS

PubMed, Web of Science, Embase, and SCOPUS were searched up to February 24, 2022 using the AutoLit platform. We included primary studies assessing the long-term outcomes for flow diverter devices to manage unruptured internal carotid artery aneurysms with a follow-up period of >1 year. The meta-analysis was carried out using Comprehensive Meta-Analysis software (CMA).

RESULTS

Eleven studies were included in the meta-analysis. The pooled occlusion rates after flow diversion treatment for unruptured intracranial brain aneurysms were 77%, 87.4%, 84.5%, 89.4%, 96% for 1 year, 1-2 years, 2 years, 3 years, and 5 years follow-up, respectively. The in-stent stenosis rate was 4.8% and the retreatment rate for the long-term follow-up period was 5%. No delayed rupture of the aneurysm was reported, and there was one case of delayed ischemic stroke. The sensitivity analysis of the prospective studies showed a complete occlusion rate of 83.5% and 85.2% for 1 and 3 years of follow-up, respectively.

CONCLUSION

Flow diverters are safe and effective in short- and long-term follow-up and rarely cause serious delayed side effects.

Distal Flow Diversion with Anti-Thrombotically Coated and Bare Metal Low-Profile Flow Diverters—A Comparison

Background and purpose: The establishment of low-profile flow diverting stents (FDS), for example, the Silk Vista Baby (SVB) and the p48MW, facilitated endovascular treatment of peripheral cerebral aneurysms. This study therefore aims to compare the performance and outcomes of the SVB with those of the p48MW HPC, with a special focus on hemodynamic aspects of peripheral segments and bifurcations. Materials and methods: The study cohort comprises 108 patients, who were either treated with the SVB or the p48MW HPC between June 2018 and April 2021. Results: Sixty patients received a SVB and forty-eight patients a p48MW HPC. The SVB was used predominantly in the AcomA-complex, and the p48MW HPC in the MCA bifurcation. Immediately after implantation, significant hemodynamic downgrading (OKM A2-A3, B1-B3, C3) was achieved in 60% in the SVB group vs. 75.1% in the p48MW HPC group. At the second follow-up, after an average of 8.8 and 10.9 months, respectively, OKM D1 was observed in 64.4% of the SVB group vs. 27.3% in the p48MW HPC group. Only 1.7% vs. 6.8% of the aneurysms remained morphologically unaltered (OKM A1). Adverse events with persisting neurologic sequalae at last follow-up were largely comparable in both groups (5.0% vs. 4.2%). Conclusion: Immediately after implantation, the p48MW HPC had a more profound hemodynamic impact than the SVB; however, early complete occlusions were achieved in a greater proportion of lesions after implantation of the uncoated SVB.

Use of flow diverter device in basilar artery for aneurysm treatment: Case series and literature review

Background

Flow diverters (FDs) for the treatment of basilar artery (BA) aneurysms remain controversial. In this study, we report our initial experience of flow diversion for treatment of this pathology.

Methods

Consecutive patients with an aneurysm of the BA that was treated by implantation of the FD were included in our retrospective study. Procedural complications, aneurysm occlusion, and a functional outcome were evaluated. FD placement in BA for aneurysm treatment reported in the literature was also reviewed and summarized.

Results

Sixteen patients with 16 BA aneurysms were treated by FD implantation with (n = 8) or without (n = 8) adjunctive coiling. The Tubridge was used in 13 (81.3%) and Pipeline in 3 (18.8%) procedures. Average aneurysm size was 15.7 mm. Four aneurysms were located at the basilar apex, six at the basilar trunk, and six at the vertebrobasilar junction. Three patients experienced procedural complications (18.8%), including two ischemic strokes and one hydrocephalus, with resultant mortality in one case (6.3%). Median follow-up was 7.7 months and available for 15 aneurysms. Complete/near-complete occlusion was seen in 13 (86.7%) aneurysms.

Conclusion

In our initial experience, flow diversion is feasible and safe in the treatment of BA aneurysms with promising occlusion rates at mid-term follow-up. Larger cohort studies are required to validate these results.

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.