Multiple overlapping stent-assisted coiling of complex aneurysms: a single-center experience

Additional rescue stenting with Neuroform Atlas stents during stent-assisted coiling of saccular aneurysms

OBJECTIVE

Overlapping stenting is sometimes attempted during endovascular treatment of cerebral aneurysm as a rescue for coil herniation, stent mal-positioning, or in-stent thrombosis. We retrospectively evaluated the efficacy and safety of additional rescue stenting (ARS) in telescoping fashion with Neuroform Atlas stent (NAS) during stent-assisted coiling of saccular aneurysms.

METHODS

We collected clinical and radiological data of patients with saccular aneurysms treated with ARS using NASs between March 2018 and December 2021. Y or X-stent-assisted coiling technique was excluded.

RESULTS

Eighteen unruptured and 5 ruptured aneurysms in 23 patients were treated with ARS using NASs. Sizes of aneurysms ranged from 2.0 mm to 10.0 mm (mean: 5.0 mm). Immediate angiographic results were complete occlusion in 11 aneurysms, residual neck in 4 aneurysms, and residual sac in 8 aneurysms. Peri-operative morbidity was 4.3 %. Nineteen of 23 patients underwent follow-up conventional angiography (mean, 9.9 months). Results showed progressive occlusion in 10 (52.6 %) cases and asymptomatic in-stent stenosis in 3 (15.8 %) cases. At the end of the observation period (mean, 17.4 months), all 18 patients without subarachnoid hemorrhage had excellent clinical outcomes (mRS of 0), except one (mRS of 1). Of five patients with subarachnoid hemorrhage, four had a favorable outcome (mRS of 0-1), while the other one was dependent (mRS of 4).

CONCLUSION

In this report on 23 patients, ARS with NASs for treating saccular aneurysms showed good technical safety with favorable clinical and angiographic outcomes. However, delayed in-stent stenosis was not uncommon. Thus, regular imaging follow-up is required.

Overlapping stents-assisted coiling for vertebral artery dissecting aneurysm: LVIS stent within Neuroform EZ stent

Objective

Methods

Results

Conclusion

Multiple overlapping stent-assisted coiling improves efficacy and safety of treatment for complex intracranial aneurysms: a randomized trial

BACKGROUND

Intracranial aneurysm rupture is the main cause of subarachnoid hemorrhage, leading to high disability and mortality. This study aimed to evaluate the clinical treatment effects of multiple overlapping stent-assisted coiling for complex intracranial aneurysms.

METHODS

We conducted a randomized, controlled, single-blinded clinical trial among 168 patients diagnosed with complex intracranial aneurysms. Treatment allocation to either single stent (SS) group or multiple stent (MS) group was randomized at 1:1 ratio using a Web-based platform. The O'Kelly-Marotta (OKM) grading scale was used to evaluate the degree of aneurysm occlusion after operation and during follow-up. Good aneurysm occlusion was defined as OKM grade C-D. The modified Rankin Scale (mRS) was used to evaluate the neurological status and the clinical outcome of patients.

RESULTS

Efficacy comparative analysis demonstrated that major recurrence of aneurysms was significantly reduced in the MS group (P = 0.012). In addition, the MS group displayed significantly reduced number of patients with mRS between 3 and 6 (P = 0.007) and increased number of patients with mRS between 0 and 1 (P = 0.034). Furthermore, the MS group showed increased percentage of patients with OKM grade C-D (P = 0.041). Compared with the SS group, the MS group exhibited decreased mortality (P = 0.037) and morbidity (P = 0.035).

CONCLUSIONS

Multiple overlapping stent-assisted coiling significantly improved the clinical treatment effects and provided a new method for complex intracranial aneurysms.

Coil and Single-Stent Placement for Ruptured Dissecting Aneurysm of Middle Cerebral Artery: A Case Report

BACKGROUND

Ruptured dissecting aneurysms located at the middle cerebral artery (MCA) are rare, and their standard treatment has not been defined. Furthermore, lenticulostriate artery involvement in the dissecting segment makes treatment extremely difficult, and no previous reports have described successful treatment for such conditions.

CASE DESCRIPTION

We herein report the case of a 74-year-old woman who presented with sudden severe headache from subarachnoid hemorrhage due to dissection in the proximal M1 segment of left MCA involving lenticulostriate arteries. Digital subtraction angiography on day 6 showed that the dissecting aneurysm had enlarged despite strict blood pressure control. On day 8, the patient was treated successfully with a self-expanding closed cell stent and coil embolization, preserving blood flow in the lenticulostriate arteries as well as the MCA.

CONCLUSIONS

Follow-up digital subtraction angiography performed 5 weeks after endovascular therapy showed healing of the dissecting lesion, and the patient was discharged neurologically intact.

Hemodynamic Changes Caused by Multiple Stenting in Vertebral Artery Fusiform Aneurysms: A Patient-Specific Computational Fluid Dynamics Study

BACKGROUND AND PURPOSE

The multiple stent placement technique has largely improved the long-term outcomes of intracranial fusiform aneurysms, but the hemodynamic mechanisms remain unclear. In this study, we analyzed the hemodynamic changes caused by different stent-placement strategies in patient-specific models using the computational fluid dynamics technique, aiming to provide evidence for clinical decision-making.

MATERIALS AND METHODS

Ten vertebral artery fusiform aneurysms were included, and their patient-specific computational fluid dynamics models were reconstructed. A fast virtual stent placement technique was used to simulate sequential multiple stent placements (from a single stent to triple stents) in the vertebral artery fusiform aneurysm models. Hemodynamic parameters, including wall shear stress, pressure, oscillatory shear index, relative residence time, and flow pattern, were calculated and compared among groups with different numbers of stents.

RESULTS

Virtual stents were deployed in all 10 cases successfully, consistent with the real stent configuration. Wall shear stress decreased progressively by 7.2%, 20.6%, and 25.8% as the number of stents increased. Meanwhile, relative residence time and pressure increased on average by 11.3%, 15.4%, and 45.0% and by 15.7%, 21.5%, and 28.2%. The oscillatory shear index showed no stable variation trend. Flow patterns improved by weakening the intensity of the vortices and displacing the vortex center from the aneurysmal wall.

CONCLUSIONS

Stent placement modifies hemodynamic patterns in vertebral artery fusiform aneurysms, which might favor thrombosis formation in the aneurysmal sac. This effect is amplified with the number of stents deployed. However, a potential risk of rupture or recanalization exists and should be considered when planning to use the multiple stent placement technique in vertebral artery fusiform aneurysms.

Overlapping stent-assisted coil embolization for a ruptured intracranial vertebral artery dissection

Ruptured intracranial vertebral artery dissection is a cause of non-traumatic subarachnoid hemorrhage. Urgent intervention should be considered to prevent fatal rebleeding. Endovascular parent artery occlusion, which is the initial treatment of choice, is not suitable for patients with a hypoplastic or occlusive contralateral vertebral artery. We report a case of ruptured vertebral artery dissection, which was successfully treated with double overlapping stent-assisted coiling.