Predictors of in-stent stenosis and occlusion after endovascular treatment of intracranial vascular disease with the Willis covered stent

Covered Stent Treatment for Direct Carotid-Cavernous Fistulas: A Meta-Analysis of Efficacy and Safety Outcomes

BACKGROUND

Direct carotid-cavernous fistulas (dCCFs) involve the abnormal shunting of blood between the internal carotid artery and the cavernous sinus. The use of covered stents (CSs) has been reported for the treatment of complex carotid artery lesions. However, the efficacy and safety of CS treatment for dCCFs remain controversial. Thus, we performed a systematic review and meta-analysis to evaluate these efficacy and safety endpoints.

METHODS

A systematic literature review was performed by comprehensively searching the Medline, Embase, and Web of Science databases to identify studies that were related to CS treatment for dCCFs. Then, a meta-analysis was conducted to pool the efficacy and safety outcomes from these studies based on perioperative and follow-up data.

RESULTS

Fourteen noncomparative studies enrolling 156 patients with 160 dCCFs met the inclusion criteria. When analyzing perioperative outcomes, the technical success rate was 98.5% [95% confidence interval (CI), 0.948; 1.000], and the immediate complete occlusion rate was 90.9% (95% CI, 0.862; 0.959). Vasospasm and dissection occurred in 32.2% (95% CI, 0.238; 0.463) and 0.1% (95% CI, 0.000; 0.012) of patients, respectively. The in-stent acute thrombus formation rate was 0.1% (95% CI, 0.000; 0.013). Postoperatively, the mortality rate was 0.1% (95% CI, 0.000; 0.013). Based on available follow-up data, the final complete occlusion and parent artery stenosis rates were 99.3% (95% CI, 0.959; 1.000) and 18.6% (95% CI, 0.125; 0.277), respectively.

CONCLUSIONS

CS placement can be used to safely and effectively treat dCCFs. These results provide a reference for future clinical trials.

Endovascular treatment of distal internal carotid artery aneurysms and vertebral artery dissecting aneurysms with the Willis covered stent: A single-center, retrospective study

BACKGROUND

More data is needed on the short- and medium-term efficacy and safety of the Willis covered stent in treating distal internal carotid artery (DICA) aneurysms and vertebral artery dissecting aneurysms (VADAs).

METHODS

Records of all 42 patients with DICA aneurysms or VADAs treated with the Willis covered stents at our institute between July 2014 and January 2019 were retrospectively examined. The patients' demographic information, symptoms, diagnosis, treatment procedure, immediate and follow-up clinical and angiographic outcomes were extracted.

RESULTS

46 Willis covered stents were successfully implanted in all of the 42 patients (total 43 aneurysms). Immediate complete aneurysm occlusion was achieved in 37 patients (38 aneurysms) (88.4%), and endoleak occurred to 5 patients (5 aneurysms) (11.6%). 2 patients died post-operatively from procedure-related complications, another one died from reasons unrelated to the procedure. Among the remaining 39 patients, non-lethal complications occurred in 4 patients including ptosis and diplopia of the right eye, intra-operative hemorrhage and carotid cavernous fistulas (CCF). Angiographic and clinical follow-ups (means ± standard deviation: 8.8 ± 5.3 months) were done for 32 patients (33 aneurysms). Complete occlusion was maintained in all of the 33 aneurysms. 2 of the 32 patients had significant though asymptomatic parent artery (PA) occlusion. No ischemic or hemorrhagic event occurred during the follow-up period. The modified Rankin Scale (mRS) score was 0 in 31 patients and 1 in the remaining 1 patient.

CONCLUSIONS

The Willis covered stent could be a safe and effective treatment for complex DICA aneurysms with excellent durability. In addition, the Willis covered stent treated all of the 3 cases of VADAs in the study with complete success without any complications, however, as the number of the VADA cases was small, more cases are needed to further confirm the efficacy and safety of the Willis covered stent in treating VADAs.

Use of covered stents to treat complex cerebrovascular diseases: Expert consensus

The treatment of complex cerebrovascular diseases (CCVDs) at the skull base, such as complex intracranial aneurysms, carotid-cavernous sinus fistulas, and intracranial artery traumatic injuries, is a difficult clinical problem despite advances in endovascular and surgical therapies. Covered stents or stent graft insertion is a new concept for endovascular treatment that focuses on arterial wall defect reconstruction, differing from endovascular lesion embolization or flow diverter therapies. In recent years, covered stents specifically designed for cerebrovascular treatment have been applied in the clinical setting, allowing thousands of patients with CCVDs to undergo intraluminal reconstruction treatment and achieving positive results, even in the era of flow diverters. Since there is no unified reference standard for the application of covered stents for treating CCVDs, it is necessary to further standardize and guide the clinical application of this technique. Thus, we organized authoritative experts in the field of neurointervention in China to write an expert consensus, which aims to summarize the results of covered stent insertion in the treatment of CCVDs and propose suitable standards for its application in the clinical setting. Based on the contents of this consensus, clinicians can use individualized intraluminal reconstruction treatment techniques for patients with CCVDs.

Willis Covered Stent for Treating Intracranial Pseudoaneurysms of the Internal Carotid Artery: A Multi-Institutional Study

OBJECTIVE

This work aimed to retrospectively analyze Willis covered stent (WCS)'s therapeutic efficacy in intracranial pseudoaneurysms (PSAs) of the internal carotid artery (ICA).

METHODS

Between June 2018 and July 2021, 56 individuals with intracranial PSAs of the ICA treated with WCS in three centers were included to analyze information regarding medical records, operative parameters, imaging findings and follow-up data.

RESULTS

All WCSs were successfully targeted to the ICA lesions. Total exclusion of PSA was found in 53 cases (94.6%) right upon surgery, and mild endoleak into the aneurysm remained in 3 cases (5.4%). Intraoperative thrombosis occurred in 1 case (1.8%), and tirofiban was utilized for recanalization. Follow-up by angiography showed total aneurysm occlusion in the total number of individuals, including in the 3 above cases with residual endoleak. In-stent stenosis occurred in 7 (12.5%) patients. No stent-related ischemic event was encountered. Predictive factors of late in-stent stenosis following WCS implantation in this patient group were irregular post-operative antiplatelet treatment (p = 0.015) and C4-C5 segment of the ICA (p = 0.043).

CONCLUSION

WCSs are effective in treating intracranial PSAs of the ICA.

Blood biomarkers of progressive atherosclerosis and restenosis after stenting of symptomatic intracranial artery stenosis

In-stent restenosis (ISR) represents a major complication after stenting of intracranial artery stenosis (ICAS). Biomarkers derived from routine blood sampling including C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and mean platelet volume (MPV) have been associated with progressive atherosclerosis. We investigated the role of CRP, NLR, PLR and MPV on the development of intracranial ISR and recurrent stroke risk. We retrospectively included all patients who had undergone stenting of symptomatic ICAS at our university hospital between 2005 and 2016. ISR (≥ 50% stenosis) was diagnosed by regular Duplex sonography follow-up studies and confirmed by digital subtraction angiography or computed tomography angiography (mean follow-up duration: 5 years). Laboratory parameters were documented before stenting, at the time of restenosis and at last clinical follow-up. Of 115 patients (mean age: 73 ± 13 years; female: 34%), 38 (33%) developed ISR. The assessed laboratory parameters did not differ between patients with ISR and those without (p > 0.1). While ISR was associated with the occurrence of recurrent ischemic stroke (p = 0.003), CRP, NLR, PLR and MPV were not predictive of such events (p > 0.1). Investigated blood biomarkers of progressive atherosclerosis were not predictive for the occurrence of ISR or recurrent ischemic stroke after ICAS stenting during a 5-year follow-up.

Case Report of Late Type IIIb Endoleak with Willis Covered Stent (WCS) and Literature Review

OBJECTIVE

We report a case of late type IIIb endoleak with Willis covered stent (WCS) developed 14 months after endovascular paraclinoid aneurysm repair.

METHODS

A 52-year-old woman presented with episodic headache, caused by a giant paraclinoid aneurysm. She underwent a successful 3.5 x 16mm WCS positioning to treat the aneurysm. Fourteen months later, the patient was admitted with the same symptoms. Digital subtraction angiography examination showed recurrence of the aneurysm, which was similar to the preoperative one. DynaCT (Siemens, Erlangen, Germany) indicated the intact of the metal structure of the stent without migration. Type IIIb endoleak (defect in the graft fabric) was confirmed with a whole aneurysm neck located in the middle part of the stent. The type IIIb endoleak was treated with another WCS (4.0 x 16mm). The immediate digital subtraction angiography imaging indicated that the endoleak disappeared and the aneurysm was completely occluded. Re-examination done 1 year after the second treatment showed a complete exclusion of the aneurysm sac.

CONCLUSIONS

Type IIIb endoleaks can be safely treated by the endovascular positioning of another WCS. Continuous surveillance after endovascular paraclinoid aneurysm repair for intracranial aneurysms is warranted to make ensure the safety of WCS.

A single-center experience in the endovascular treatment of carotid siphon aneurysms using the Willis covered stent: a retrospective analysis

OBJECTIVE

To report the clinical results and initial clinical experience of endovascular isolation with the Willis covered stent for carotid siphon aneurysms.

METHODS

Between November 2013 and December 2016, a total of 57 patients who presented with carotid siphon aneurysms were treated with the Willis covered stent. Results of the procedures, technical events, and complications were recorded. Clinical and imaging follow-ups were performed at 3 months following the endovascular procedures.

RESULTS

Placement of the Willis covered stent was successful in all patients. Immediate angiography revealed complete exclusion of aneurysms in 48 patients (84%), while endoleak occurred in nine patients (16%). Procedure-related complications occurred in three cases, including displacement of the covered stent in one patient, acute in-stent thrombosis in one patient, and microwire-related intracranial hemorrhage in one patient. Angiographic follow-ups were done in 49 patients, with complete exclusion of aneurysms in 47 patients. Endoleak was present in two patients. No aneurysm recurrence occurred. Forty-four patients showed good parent artery patency, while the other five patients showed mild to moderate asymptomatic in-stent stenosis. During the follow-up period, no ischemic or hemorrhagic event occurred. The modified Rankin Scale scores at follow-up were 0-2 in 56 patients and >2 in one patient.

CONCLUSIONS

The treatment of siphon aneurysms with Willis covered stent implantation resulted in satisfactory clinical outcomes. The Willis covered stent seems safe and feasible for the treatment of siphon aneurysms, which still needs to be confirmed by longer follow-up periods and controlled studies with larger samples.

Efficacy and Safety of Willis Covered Stent for Treatment of Internal Carotid Artery Aneurysms

OBJECTIVE

The purpose of this study was to evaluate the clinical and short-term outcome of patients who underwent covered stent treatment for internal carotid artery aneurysms.

METHODS

Twelve cases patients with internal carotid artery aneurysms were treated with Willis covered stents during the period from December 2010 to January 2016. The guiding catheter was placed as high as possible to facilitate the delivery of the covered stent system.

RESULTS

Covered stent placement was successful in 11 of 12 case patients (91.6%), embolization was successful in 11 of 12 patients (91.6%), the treatment in 1 patient of 12 cavernous aneurysms patients was performed covered stents +ONYX + plastic coil embolization, and the other was used Willis covered stents. The results indicated that only 1 of 12 patients underwent postoperative massive cerebral infarction, but was successfully rescued. The angiographic following-up of patients using covered stent suggested that 12 cases patients were complete occlusion and the parent artery patency. Clinical follow-up results also demonstrated that clinical neurologic symptoms fully recovered in 11 of 12 cases patients, another case improved and were not aggravated in any patient before discharge and had aggravated symptoms.

CONCLUSION

Willis covered stents are effective for treatment of internal carotid artery aneurysms with good safety and short-term outcomes.

In-stent stenosis in the patient with internal carotid aneurysm after treated by the Willis covered stent: Two case reports and literature review

In-stent stenosis after treated by Willis covered stent-case reports.

BACKGROUND

Advancements in minimally invasive technology have allowed endovascular reconstruction of internal carotid aneurysm. However, in-stent stenosis is an important and well-characterized complication of stenting after the treatment of internal carotid aneurysm.

CASE DESCRIPTION

We would present 2 patients who were diagnosed with in-stent stenosis after the treatment of Willis covered stent. Case 1: A 57-year-old female with 2-week history of headache and vomiting before admission, whose digital subtraction angiography (DSA) demonstrated left internal carotid C6 aneurysm and showed about 20% stenosis 3 months later since operation in the position where Willis covered stent was deployed. Case 2: A 23-year-old male with skull base fracture, subarachnoid hemorrhage, right femoral fracture for 14 days and epistaxis for 9 hours caused by a car accident, whose DSA demonstrated left internal carotid paracliniod pseudoaneurysm. One year later, the patient went to our center again because he had headache and dizziness for 6 months after the interventional operation. His DSA demonstrated about 80% stenosis in the position where Willis covered stent was deployed. The clinical and radiologic characteristics and the experience in dealing with the stenosis are presented.

CONCLUSIONS

In-stent stenosis after treated with Willis covered is uncommon, but not rare. Operators should pay more attention to the in-stent stenosis during the period of follow-up observation and monitor P2Y12 Reaction Unit (PRU) in the antiplatelet period, especially for the Willis covered stent. What is more, the treatment for stenosis ought to be carefully considered.

Endovascular isolation of intracranial blood blister-like aneurysms with Willis covered stent

Objective

Intracranial blood blister-like aneurysm (BBA) is a rare type of aneurysm that lacks all layers of the arterial wall. These fragile aneurysms have the propensity to rupture with minimal manipulation, which makes them hazardous and difficult to treat. The present study evaluated the safety and feasibility of endovascular treatment of BBAs with the Willis covered stent.

Materials

Thirteen patients (7 men and 6 women, age range 28–68 years) who presented with ruptured BBAs and were treated with the Willis covered stent were retrospectively reviewed. Results of the procedures and treatment-related complications were recorded. Angiographic and clinical follow-ups were performed 4–6 months after the procedure.

Results

Placement of the covered stent was successful in all patients. Immediate angiography showed complete aneurysm occlusion in 12 patients while one patient showed a mild endoleak. This high rate of aneurysm exclusion ensured the security of postoperative antiplatelet treatment. Occlusion of the ophthalmic artery occurred in two patients and occlusion of the anterior choroidal artery occurred in one patient; however, none of them showed acute or delayed clinical symptoms. Thrombosis, aneurysm rupture, and other complications did not develop in any case. Angiographic follow-up showed complete aneurysm exclusion without aneurysm recurrence in any patients. Only two patients showed asymptomatic mild to moderate in-stent stenosis. All patients had satisfactory clinical outcomes (modified Rankin Scale score ≤1).

Conclusions

Willis covered stent implementation may be safe and feasible for BBAs. This strategy might be a promising option for this high-risk type of aneurysm.