Comparative Analysis of Long-Term Effect of Stent-Assisted Coiling in Unruptured Sidewall-Type and Terminal-Type Aneurysms

Anterior circulation location-specific results for stent-assisted coiling - carotid versus distal aneurysms: 1-year outcomes from the Neuroform Atlas Stent Pivotal Trial

BACKGROUND

The Neuroform Atlas Stent System is an established treatment modality for unruptured anterior and posterior circulation intracranial aneurysms. Location-specific results are needed to guide treatment decision-making. However, it is unclear whether there are differences in safety and efficacy outcomes between carotid and more distal anterior circulation aneurysms.

METHODS

The ATLAS IDE trial was a prospective, multicenter, single-arm, open-label interventional study that evaluated the safety and efficacy of the Neuroform Atlas Stent System. We compared differences in efficacy and safety outcomes of proximal internal carotid artery (ICA) versus distal and bifurcation anterior circulation aneurysms.

RESULTS

Of 182 cases, there were 70 aneurysms in the ICA and 112 in the distal anterior circulation (including ICA terminus/bifurcation). There were no significant differences in the primary efficacy endpoint (85.5% vs 83.9%, p=0.78) and complete aneurysm occlusion rates (88.7% vs 87.9%, p=0.78) between proximal ICA aneurysms and distal aneurysms, respectively. Complications were more often encountered in distal and bifurcation aneurysms, but the overall rate of major safety events was low and comparable between the two groups (1.4% vs 6.3%, p=0.14). Recanalization and retreatment rates were also similar between the groups.

CONCLUSION

The results of this study suggest that the Neuroform Atlas Stent System is a safe and efficacious treatment modality for unruptured anterior circulation intracranial aneurysms, regardless of aneurysm location.

TRIAL REGISTRATION NUMBER

NCT02340585.

Trends in the Age of Patients Treated for Unruptured Intracranial Aneurysms from 1990 to 2020

BACKGROUND

The decision for treatment for unruptured intracranial aneurysms (UIAs) is often difficult. Innovation in endovascular devices have improved the benefit-to-risk profile especially for elderly patients; however, the treatment guidelines from the past decade often recommend conservative management. It is unknown how these changes have affected the overall age of the patients selected for treatment. Herein, we aimed to study potential changes in the average age of the patients that are being treated over time.

METHODS

A systematic search of the literature was performed to identify all studies describing the age of the UIAs that were treated by any modality. Scatter diagrams with trend lines were used to plot the age of the patients treated over time and assess the presence of a potential significant trend via statistical correlation tests.

RESULTS

A total of 280 studies including 83,437 UIAs treated between 1987 and 2021 met all eligibility criteria and were entered in the analysis. Mean age of the patients was 55.5 years, and 70.7% were female. There was a significant increasing trend in the age of the treated patients over time (Spearman r: 0.250; P < 0.001), with a 1-year increase in the average age of the treated patients every 5 years since 1987.

CONCLUSIONS

The present study indicates that based on the treated UIA patient data published in the literature, older UIAs are being treated over time. This trend is likely driven by safer treatments while suggesting that re-evaluation of certain UIA treatment decision scores may be of great interest.

A Case of Horizontal Stent-assisted Coiling for an Aneurysm Arising from Fenestration of the Vertebral Artery: A Technical Case Report

Horizontal stenting protects the aneurysm neck with stent deployment across the aneurysm neck via the circle of Willis. A saccular aneurysm associated with intracranial arterial fenestration is very rare. Herein, we describe the first case of an unruptured aneurysm related to intracranial arterial fenestration treated with horizontal stenting. A 23-year-old woman presented with a 7-mm broad-necked aneurysm at the fenestration of the right intracranial vertebral artery (VA), which was incidentally found on magnetic resonance imaging. The patient underwent endovascular treatment with horizontal stenting via the vertebrobasilar junction from the contralateral left VA, followed by coil embolization using a jailed microcatheter from the ipsilateral right VA. The procedure was finished with sufficient embolization, and no complications occurred. Horizontal stent delivery via the vertebrobasilar junction for coil embolization of a broad-necked aneurysm arising from the fenestration of the VA is a safe and effective therapeutic strategy.

Two-center experience with Neuroform Atlas stent-assisted coil occlusion of broad-based intracranial aneurysms

PURPOSE

Stent-assisted coiling (SAC) represents an established treatment option for broad-based intracranial aneurysms. Here we report our initial and follow-up experience with the Neuroform Atlas Stent, a hybrid open- and closed-cell low-profile stent in the treatment of broad-based aneurysms.

METHODS

All intracranial aneurysms treated by SAC with the intention to apply the Neuroform Atlas Stent between July 2015 and December 2019 were included. Angiographic and clinical results were analyzed including all follow-up examinations.

RESULTS

A total of 119 aneurysms (8 acutely ruptured) in 112 patients were included. In 19 cases (16.0%) re-catheterization of the aneurysm was performed in a second procedure after failure to re-cross the stent initially. Of all aneurysms, 83.2% (99/119) were completely occluded following the procedure. In 75.6% of all cases (90/119), a single microcatheter was used for both, implantation of the stent and coil occlusion of the aneurysm. At 3-6 and 12 months follow-up, the complete occlusion rates were 75.2 (79/105) and 81.3% (74/91). The thromboembolic (stent thrombosis) and hemorrhagic complication rate was 1.7 (2/119) and 0.8% (1/119), respectively, resulting in a procedure-related morbidity and mortality rate of 0.9 and 0.9% (1/112 patients).

CONCLUSION

SAC using the Neuroform Atlas Stent offers a safe and effective option to treat broad-based intracranial aneurysms with a high angiographic and clinical success rate. In the majority of procedures, the application of two mircocatheters is not required. Prospective comparative studies might help to identify the value of SAC using the Neuroform Atlas Stent among the growing treatment options for broad-based aneurysms.

＜Editors' Choice＞ Initial experience with in vivo "endovascular shaping" technique that utilizes the vascular configuration for small cerebral aneurysm coiling

Optimal shaping of a microcatheter tip is a key factor in cerebral aneurysm coiling. However, safe cannulation and stabilization of a microcatheter can be technically challenging with small aneurysms requiring precise microcatheter shaping. We devised a new microcatheter shaping technique which bends a microcatheter tip in the intended direction by placing and keeping the tip in the selected branch of the parent artery for 5 minutes: endovascular shaping technique. Our method can complete microcatheter shaping only inside the patient's body; an endovascularly shaped microcatheter will never face a straightening deformity and rotation problem associated with catheter reinsertion. The aim was to assess the feasibility and safety of endovascular shaping for small aneurysm coiling. Clinically, 10 consecutive challenging small terminal-type aneurysms (< 5 mm) treated with endovascular shaping were included. We retrospectively analyzed the newly acquired bend angle of a microcatheter tip after the shaping, the procedural success, and clinical outcomes. An artificial vascular model was used to confirm our findings. In all the 10 patients (three middle cerebral artery, four anterior communicating artery, and three basilar artery aneurysms), the endovascularly shaped microcatheters were bent toward the placement branch at an average of 21.7° and excellently guided into the aneurysms. Coil embolization was successfully accomplished without any complications. The results of the vascular model experiment demonstrated that an endovascularly shaped microcatheter acquired new bend angle toward the placement branch. Endovascular shaping was feasible and safe for small terminal-type aneurysm coiling. Our method can provide accurate shaping and stability during aneurysm coiling procedure.

Endovascular coil embolization of proximal middle cerebral artery aneurysms has better outcomes than other middle cerebral artery aneurysms: A retrospective study

Purpose

Although some authors proposed that coil embolization in middle cerebral artery (MCA) aneurysms is a useful and effective alternative, the characteristics of the aneurysms may be different at each location. We compared the results of coil embolization of proximal middle cerebral artery aneurysms with those of other middle cerebral artery aneurysms.

Methods

Data from 46 patients with 50 aneurysms were retrospectively evaluated. We defined the aneurysms inside of the insular cortex as proximal MCA (pMCA) aneurysms and those outside of the insular cortex as non-proximal MCA (npMCA) aneurysms. The results of the occlusion were divided into classes 1, 2, and 3 of the Raymond scale. We collected the results of the occlusion from the operative notes supplied by a neuroendovascular specialist.

Results

Univariate analysis identified favorable results for pMCA aneurysms (class 1: pMCA = 22 npMCA = 11; P < 0.01). In the radiological follow-up results, we achieved class 1 in 29 patients (69%; pMCA = 21 and npMCA = 8; P < 0.01). Side wall type aneurysms (pMCA = 14, npMCA = 2; P < 0.01) and the number of branches from the neck of ≤1 (pMCA = 14, npMCA = 2; P < 0.01) were significantly recognized at the pMCA.

Conclusions

Proximal middle cerebral artery aneurysm clipping is difficult because the origin of the lenticulostriate arteries is often hidden behind the aneurysmal dome. In the present study, endovascular coil embolization for pMCA aneurysms obtained better results than that for npMCA aneurysms because of the morphological characteristics. Endovascular coil embolization seems to be efficacious for pMCA aneurysms as compared with npMCA aneurysms.