Y-Stenting for Bifurcation Aneurysm Coil Embolization: What is the Risk?

Drill turn technique for enhanced visualization of wide-neck bifurcation aneurysms in Y-stent-assisted coiling with LVIS EVO stents: technical considerations and mid-term results

BACKGROUND

Crossing Y-stent-assisted coiling (CYSAC) is a feasible yet technically challenging technique for the treatment of wide-neck bifurcation aneurysms (WNBAs).

OBJECTIVE

To present mid-term results of Y-stent-assisted coiling (YSAC) using the LVIS EVO stent and to describe our "drill turn" technique for stent crossing.

METHODS

This retrospective, observational study included 37 consecutive patients treated with YSAC using LVIS EVO stents at five centres between September 2020 and March 2023.

RESULTS

Immediately after treatment, 31 of the 37 patients (83.8%) achieved Raymond-Roy occlusion classification (RROC) Class I occlusion, while 5 patients (13.5%) had Class II and 1 patient (2.7%) had Class III occlusion. The mean follow-up period was 32.8 months (range: 11-41 months), and all patients underwent follow-up imaging after ≥ 6 months. On follow-up imaging, 34 patients (92%), including all those with immediate RROC Class I occlusion, 2 with Class II, and 1 with Class III, showed Class I occlusion. One patient with RROC Class II occlusion demonstrated a gradual decrease in residual filling, while one large partially thrombosed middle cerebral artery aneurysm and one large basilar tip aneurysm (8%) with residual neck filling remained unchanged on the 6-month digital subtraction angiograph.

CONCLUSION

Utilizing the described drill turn technique, CYSAC with LVIS EVO stents was found to be feasible and safe for WNBA treatment, with high and stable occlusion rates observed during mid-term follow-up.

Effect of the Shelving Technique on the Outcome of Embolization in Intracranial Bifurcation Aneurysms

BACKGROUND AND PURPOSE

Stent bulging technique has been introduced as a technique that improves the outcome of aneurysm coiling. Our aim was to evaluate the utility of this technique, which involves the intentional herniation of stents into the bifurcation aneurysms during coiling.

MATERIALS AND METHODS

Unruptured bifurcation aneurysms treated by stent-assisted coiling using a single type of low-profile braided (LEO Baby) stent between November 2012 and October 2018 were retrospectively evaluated. The clinical (age and sex) and morphologic characteristics (aneurysm size, neck size, proximal/distal diameters of the stented artery, incorporation of the origins of the side branches to the aneurysm neck, and bifurcation angle) and response to antiplatelet therapy were evaluated.

RESULTS

Sixty-one patients (29 men, 47.5%; mean age, 55.95 [SD, 12.33] years) with 66 aneurysms were included. There were 36 aneurysms in group A (treated with the stent bulging technique) and 30 aneurysms in group B (treated by classic stent-assisted coiling). There was no significant difference in the patient and aneurysm characteristics in the groups except for the larger size and wider neck of the aneurysms in group A (P = .02 and P = .04, respectively). At the mean follow-up of 27.30 (SD, 17.45) months, there was no significant difference in the complication rate, the occlusion status, and the early and long-term occlusion rates between the groups. The stent bulging technique did not predict total occlusion (Raymond-Roy I) at the final imaging follow-up.

CONCLUSIONS

The stent bulging technique enables the coiling of larger, wide-neck aneurysms; however, we did not observe an added flow-diversion effect with the stent bulging technique compared with conventional stent-assisted coiling. We, therefore, suggest that bifurcation aneurysms should be coiled as densely and as safely as possible using this technique.

Update on Clinical Management with Neurovascular Stents

Endovascular stenting has continued to evolve given the new trials. Several new stents have recently been developed to address specific purposes. In this focused review, we discuss the concepts of neurointerventional stents and address the clinical implications. Furthermore, each type of stent is discussed with supporting evidence for clinical utility. In the final component, we argue for continued development and utilization.

Y-stent-assisted coiling with Neuroform Atlas stents for wide-necked intracranial bifurcation aneurysms: A preliminary report

Objective

To report our experience on Neuroform Atlas Y-stenting for coiling of unruptured wide-neck bifurcation aneurysms.

Methods

From March 2018 to January 2021, we treated 473 aneurysms in 436 patients with coil embolization, of which 15 cases with wide-necked bifurcation aneurysms were treated by Y-stent-assisted coiling with two Neuroform Atlas stents. We retrospectively reviewed the characteristics of patients and aneurysms, procedure-related complications, radiographic results, and clinical outcomes.

Results

All 15 cases using Neuroform Atlas Y-stenting were successful. Patients included 6 men and 9 women with a mean age ± standard deviation of 56.4±6.6 years. The mean dome and neck sizes were 6.4±3.1 mm and 4.7±1.8 mm, respectively. Immediate post-procedural angiograms showed complete occlusion in 46.7%, neck remnant in 13.3%, and incomplete occlusion in 40% of cases. No treatment-related morbidity or mortality occurred in any patients. All patients had good clinical outcomes (Glasgow Outcome Score 5) at both discharge and during a mean 12.3-month (range 1-28 months) follow-up. All aneurysms showed improved or stable occlusion on follow-up imaging. Further, the latest follow-up angiography showed complete occlusion in 73.3%, neck remnant in 6.7%, and incomplete occlusion in 20%.

Conclusions

Y-stent-assisted coiling with Neuroform Atlas stents might be a feasible and safe option for wide-necked bifurcation aneurysms.

Strut remodeling with hypercompliant balloon: A new approach to Y stent-assisted coil embolization in the treatment of complex wide-neck bifurcation aneurysms

BACKGROUND

The objective of this study was to present the long-term safety and effectiveness of strand remodelling with a hypercompliant balloon.

METHODS

Patients with complex wide-neck bifurcation aneurysms (WNBAs) who underwent strand remodelling with a hypercompliant balloon via Y-stent-assisted coil embolization (Y-SACE) between September 2016 and January 2020 were included in the study. The feasibility, safety, effectiveness, and complication rates of the strand remodelling technique were investigated.

RESULTS

A total of 12 patients (6 females, 6 males) were included in this study. Significant expansion was obtained in the intersection zone after remodelling. No regression was observed in the expansion rates during follow-up. There was no additional morbidity or mortality. No delayed thromboembolic complications occurred in our patients during long-term follow-up.

CONCLUSIONS

Performing strand remodelling to reduce thromboembolic complications triggered by structural faults caused by the Y-stent configuration is feasible, safe, and effective. This new approach can aid in the prevention of thromboembolic complications in Y-SACE.

Analysis of branch artery orifice angulation: Feasibility of the shelf technique for the treatment of wide-neck bifurcation aneurysms

BACKGROUND AND PURPOSE

The aim of this study was to investigate the feasibility of the shelf technique by analyzing the angle between the two branch orifices and to present its safety and effectiveness compared with that of the double-stent technique.

MATERIALS AND METHODS

Patients with complex wide-neck bifurcation aneurysms (WNBAs) who underwent stent-assisted coiling (SAC) were reviewed. The study sample was divided into two groups: single SAC (shelf technique) and double SAC. The angle between the lines connecting the superior and inferior points of each branch orifice (α angle) was measured by two neurointerventional radiologists in both groups. The inter- and intraobserver repeatability and consistency of the α angle were assessed. The effect of the α angle on the feasibility of using the shelf technique to treat WNBA was analyzed. Technical and clinical success rates were investigated by comparing both groups.

RESULTS

Forty-eight patients (32 shelf technique and 16 double-stent technique) were included. There was excellent agreement between the intra- and interobserver repeatability and consistency of α angle measurements. The α angle was smaller in the shelf technique group than in the double-SAC group (p < 0.001). The technical and clinical success rates of both groups were similar based on long-term follow-up (p > 0.05).

CONCLUSION

WNBA treatment with the shelf technique is safe and effective. The α angle is a useful parameter to evaluate the performance of the shelf technique. The shelf technique is more suitable for WNBAs with a narrow α angle.

Efficacy and safety of PulseRider for treatment of wide-necked intracranial aneurysm-A systematic review and meta-analysis

OBJECTIVE

PulseRider is a novel self-expanding nickel-titanium (nitinol) stent for treatment of wide-necked aneurysms, which is commonly located at the arterial branches in the brain. This systematic review and meta-analysis aims to assess the efficacy and safety of PulseRider for treatment of wide-necked intracranial aneurysm.

METHOD

We performed a systematic literature search on articles that evaluate the efficacy and safety of PulseRider-assisted coiling of the wide-necked aneurysm from several electronic databases. The primary endpoint was adequate occlusion, defined as Raymond-Roy Class I + Raymond-Roy Class II upon immediate angiography and at six-month follow-up.

RESULTS

There were a total of 157 subjects from six studies. The rate of adequate occlusion on immediate angiography was 90% (95% CI, 85%-94%) and 91% (95% CI, 85%-96%) at six-month follow-up. Of these, Raymond-Roy Class I can be observed in 48% (95% CI, 41%-56%) of aneurysms immediately after coiling, and 64% (95% CI, 55%-72%) of aneurysms on six-month follow-up. Raymond-Roy Class II was found in 30% (95% CI, 23%-37%) of aneurysms immediately after coiling, and 25% (17-33) after six-month follow-up. Complications occur in 5% (95% CI, 1%-8%) of the patients. There were three intraoperative aneurysm rupture, three thrombus formation, three procedure-related posterior cerebral artery strokes, one vessel dissection, and one delayed device thrombosis. There was no procedure/device-related death.

CONCLUSIONS

PulseRider-assisted coiling for treatment of patients with wide-necked aneurysm reached 90% adequate occlusion rate that rises up to 91% at sixth month with 5% complication rate.

Double Stent-Assisted (Y and X) Coil Embolization of Unruptured Intracranial Saccular Aneurysms using the Low-Profile Visualized Intraluminal Support Device-Single Center Experience

PURPOSE

To study the feasibility, safety, and durability of the dual stent-assisted coil embolization (DSCE) technique using low-profile visualized intraluminal support (LVIS) device.

METHODS

Retrospective review of our aneurysm database to identify all the patients treated with LVIS stent-assisted embolization between July 2015 and June 2017 was performed. 15% of the patients with Y- or X-configuration DSCE constituted the study population. Patient demographics, clinical presentation, aneurysm characteristics (location, dome, and dome/neck ratio), periprocedural complications, immediate and follow-up angiographic and clinical outcomes were reported.

RESULTS

Twelve patients (15%) with unruptured, wide-necked branching aneurysms underwent DSCE using LVIS Junior stents. M:F-1:11. Mean age of 60 ± 11 years. 75% (n = 9) aneurysms are located in anterior circulation. Recurrent aneurysms were treated in 17% (n = 2). Mean aneurysm diameter was 8 ± 3.4 mm and the dome/neck ratio was 1.6 ± 0.4. Periprocedural complications were noted in 25% (n = 3; transient in-stent thrombus = 2 and iatrogenic rupture = 1) with no clinical sequelae. Immediate aneurysm obliteration following DSCE was noted in all (100%) patients. Mean time-of-flight (TOF) magnetic resonance angiography (MRA) follow-up was 10 ± 6 months (Range: 5-19 months). Mean clinical follow-up was 12 ± 6 months (Range: 5-21 months). Stable neck recurrence was demonstrated in 25% (n = 3). The average modified Rankin Score (mRS) at prestent, 24-hour poststent, and last clinical follow-up were: 0.5 (Range: 0-1), 0.75 (Range: 0-1), and 0.5 (Range: 0-1), respectively.

CONCLUSION

We report the first dedicated DSCE experience with LVIS Junior stents in the literature. DSCE with LVIS Junior stents for intracranial complex wide-neck branching aneurysms is feasible, safe, and effective with good clinical outcomes.

Stent-assisted coiling of cerebral aneurysms using the Y-stenting technique: a systematic review and meta-analysis

BACKGROUND

Bifurcation aneurysms can be treated with stent-assisted coiling using two stents in a Y-configuration. We aim to investigate the angiographic and clinical outcomes of Y-stent constructs for the treatment of intracranial aneurysms.

METHODS

A systematic review of PubMed, Ovid MEDLINE, and Ovid EMBASE databases was conducted based on PRISMA guidelines. The study selection was performed using the 'Ryyan' application. Our analysis included 18 studies with 327 patients. Inclusion criteria were: articles published from January 2000 to November 2017, English language, including cerebral aneurysms treated via Y-stenting, and ≥5 cases with radiographic/clinical outcomes. Technical notes, editorials, reviews, and animal studies were excluded. A random-effect meta-analysis was performed on angiographic and clinical outcomes, including aneurysm occlusion, modified Rankin Scale, neurological outcome, and procedure-related mortality. 95% CIs and event rates were estimated. Statistical heterogeneity was assessed using I² statistics.

RESULTS

The procedure-related good outcome rate was 92% and complete occlusion rate was 91%. The permanent neurological deficit rate was 4% and procedure-related mortality was 2%. The procedure-related stroke rate was 12%. A total of 28/146 (19%) patients had ruptured aneurysms. At long-term follow-up, overall stroke rate was 9% in patients with unruptured aneurysm. The mortality rate was higher in cases with ruptured aneurysms than in those with unruptured aneurysms (18% vs 0.8%; p<0.001).

CONCLUSIONS

Y-stenting for bifurcation aneurysms yields a high rate of complete occlusion and low rates of mortality and stroke. Careful patient selection is needed.

Initial and Long-Term Outcomes of Complex Bifurcation Aneurysms Treated by Y-Stent-Assisted Coiling with Low-Profile Braided Stents

BACKGROUND AND PURPOSE

Coiling complex intracranial bifurcation aneurysms often necessitates the implantation of double stents in various configurations, such as Y-stent placement. Low-profile braided stents have been introduced recently to facilitate the endovascular treatment of wide-neck aneurysms. We aimed to investigate the feasibility, safety, efficacy, and durability of Y-stent-assisted coiling with double low-profile braided stents for the treatment of complex bifurcation aneurysms.

MATERIALS AND METHODS

A retrospective review was performed to identify patients who were treated using Y-stent-assisted coiling with low-profile braided stents. Technical success was assessed, as were initial and follow-up clinical and angiographic outcomes. Periprocedural and delayed complications were reviewed. Preprocedural and follow-up clinical statuses were assessed using the modified Rankin Scale.

RESULTS

Forty patients with 40 intracranial aneurysms were included in the study. Y-stent placement was successfully performed in all cases. Immediate postprocedural digital subtraction angiography images revealed total aneurysm occlusion in 72.5% of cases. The mean angiographic follow-up time was 24.8 months. The last follow-up angiograms showed complete occlusion in 85% of patients. During follow-up, only 1 patient showed an increase in the filling status of the aneurysm and that patient did not require retreatment. There was no mortality in this study. The overall procedure-related complication rate, including asymptomatic complications, was 17.5%. A permanent morbidity developed in 1 patient (2.5%).

CONCLUSIONS

The long-term angiographic and clinical outcomes of this retrospective study demonstrate that Y-stent-assisted coiling using low-profile braided stents is an effective, relatively safe, and durable endovascular treatment for wide-neck and complex bifurcation aneurysms.

LVIS Jr Device for Y-Stent-Assisted Coil Embolization of Wide-Neck Intracranial Aneurysms: A Multicenter Experience

Background and Purpose

Complex wide-neck intracranial aneurysms are challenging to treat. We report a multicenter experience using the LVIS Jr stent for "Y-stent"-assisted coiling embolization of wide-neck bifurcation aneurysms.

Methods

Seven centers provided retrospective data on patients who underwent Y-stenting. Technical complications, immediate posttreatment angiographic results, clinical outcomes, and imaging follow-up were assessed.

Results

Thirty patients/aneurysms were treated: 15 basilar tip, 8 middle cerebral artery, 4 anterior communicating artery, 1 pericallosal, and 2 posterior inferior cerebellar artery aneurysms. The mean aneurysm size was 11 mm and the mean dome-to-neck ratio was 1.3 mm. Twenty-four aneurysms were unruptured and treated electively, and 6 were acutely ruptured. Fifty-eight LVIS Jr stents were successfully deployed without any technical issue. One pro-cedural and transient in-stent thrombosis resolved with the intravenous infusion of a glycoprotein IIb/IIIa inhibitor. Five periprocedural complications (within 30 days) occurred: 2 periprocedural neurological complications (1 small temporal stroke that presented with transient aphasia and 1 posterior cerebral artery infarct) and 3 nonneurological periprocedural complications (2 retroperitoneal hematomas, and 1 patient developed a disseminated intravascular coagulopathy). One permanent complication (3.3%) directly related to Y-stenting was reported in the patient who suffered the posterior cerebral artery infarct. Immediate complete obliteration (Raymond-Roy Occlusion Classification [RROC] I-II) was achieved in 26 cases (89.6%). Twenty-four patients had clinical and imaging follow-up (mean 5.2 months). Complete angiographic occlusion (RROC I-II) was observed in 23 patients (96%). A good functional outcome with a modified Rankin Scale score ≤2 was achieved in 26 cases.

Conclusions

In this multicenter case series, Y-stent-assisted coiling of wide-neck aneurysms with the LVIS Jr device was feasible and relatively safe. Follow-up imaging demonstrated very low recanalization rates.

Usefulness of Non-Contrast-Enhanced MR Angiography Using a Silent Scan for Follow-Up after Y-Configuration Stent-Assisted Coil Embolization for Basilar Tip Aneurysms

BACKGROUND AND PURPOSE

Y-configuration stent-assisted coil embolization is used for treating wide-neck aneurysms. Noninvasive alternatives to x-ray DSA for follow-up after Y-configuration stent-assisted coil embolization treatment are required. This study aimed to assess the usefulness of non-contrast-enhanced MRA by using a Silent Scan (silent MRA) for follow-up after Y-configuration stent-assisted coil embolization for basilar tip aneurysms.

MATERIALS AND METHODS

Seven patients treated with Y-configuration stent-assisted coil embolization for basilar tip aneurysms underwent silent MRA, 3D TOF-MRA, and DSA. Silent MRA and 3D TOF-MRA images were obtained during the same scan session on a 3T MR imaging system. Two neuroradiologists independently reviewed both types of MRA images and subjectively scored the flow in the stents on a scale of 1 (not visible) to 5 (nearly equal to DSA) by referring to the latest DSA image as a criterion standard. Furthermore, we evaluated the visualization of the neck remnant.

RESULTS

In all patients, the 2 observers gave a higher score for the flow in the stents on silent MRA than on 3D TOF-MRA. The average score ± standard deviation was 4.07 ± 0.70 for silent MRA and 1.93 ± 0.80 (P < .05) for 3D TOF-MRA. Neck remnants were depicted by DSA in 5 patients. In silent MRA, neck remnants were depicted in 5 patients, and visualization was similar to DSA; however, in 3D TOF-MRA, neck remnants were depicted in only 1 patient.

CONCLUSIONS

Silent MRA might be useful for follow-up after Y-configuration stent-assisted coil embolization.

Vascular angular remodeling by kissing-Y stenting in wide necked intracranial bifurcation aneurysms

Introduction

Single stent deployment leads to a change in vascular geometry in wide necked bifurcation aneurysms. In some complex cases, the use of the single stent technique might not be sufficient or may not be feasible. The kissing-Y stenting technique appears to be an alternative endovascular treatment option. The aim of this study was to evaluate the effects of the kissing-Y stenting technique on vascular angular remodeling.

Methods

21 patients with wide necked intracranial bifurcation aneurysms at different sites (10 anterior communicating artery, 6 middle cerebral artery, 3 basilar artery, 1 vertebral artery/posterior inferior cerebellar artery, 1 internal carotid artery/posterior communicating artery) were treated with 44 closed cell stents (follow-up 2012–2016) using the kissing-Y stenting technique. We analyzed vascular angle geometry between the mother and both affected daughter vessels by digital subtraction angiography, before and after stent deployment, using standard working projections.

Results

Endovascular treatment of wide necked intracranial aneurysms using the kissing-Y stenting technique significantly decreased the angle between the bifurcation branches from 130.4±9.5° to 91.5±9.1° (p<0.0001).

Conclusions

Kissing-Y stenting in wide necked bifurcation aneurysms leads to vascular angular remodeling of both affected branches. The resulting straightening of the bifurcation angle may prevent aneurysmal recurrence.