The pCONUS2 and pCONUS2 HPC Neck Bridging Devices : Results from an International Multicenter Retrospective Study

INTRODUCTION

Bifurcation aneurysms represent an ongoing endovascular challenge with a variety of techniques and devices designed to address them. We present our multicenter series of the pCONUS2 and pCONUS2 HPC devices when treating bifurcation aneurysms.

METHODS

We performed a retrospective review of our prospectively maintained databases at 3 tertiary neurointerventional centers to identify all patients who underwent coil embolization with the pCONUS2 or pCONUS2 HPC device between February 2015 and August 2021. We recorded baseline demographics, aneurysm data, complications, immediate and delayed angiographic results.

RESULTS

We identified 55 patients with 56 aneurysms, median age 63 years (range 42-78 years), 67.3% female (n = 37). The commonest aneurysm location was the MCA bifurcation (n = 40, 71.4%). Average dome height was 8.9 ± 4.2 mm (range 3.2-21.5 mm), average neck width 6.4 ± 2.5 mm (range 2.6-14 mm), and average aspect ratio 1.3 ± 0.6 (range 0.5-3.3). The pCONUS2 was used in 64.3% and the pCONUS2 HPC in 35.7%. The procedural technical success rate was 98.2%. Intraoperative complications occurred in 5 cases (8.9%), 4 of which were related to the coils with partial thrombus formation on the pCONUS2 HPC seen in 1 case that was resolved with heparin. In relation to the procedure and treatment of the aneurysm the overall permanent morbidity was 1.8% (n = 1/55) and mortality 0%. Delayed angiographic follow-up (48 aneurysms) at median 12 months postprocedure (range 3-36 months) demonstrated adequate occlusion of 83.4% of aneurysms.

CONCLUSION

The pCONUS2 and pCONUS2 HPC devices carry a high technical success rate, low complication and retreatment rate, and good rates of adequate occlusion. Larger prospective confirmatory studies are required.

Long-Term Outcomes of the WEB Device for Treatment of Wide-Neck Bifurcation Aneurysms

BACKGROUND AND PURPOSE

Treatment of wide-neck bifurcation aneurysms using endovascular therapy is still challenging even with the development of treatment devices. The purpose of this investigation was to assess the safety and efficacy of treatment with a Woven EndoBridge (WEB) device for wide-neck bifurcation aneurysms.

MATERIALS AND METHODS

All patients treated with a WEB device at our institution between May 2009 and November 2016 were retrospectively evaluated. Clinical and imaging evaluation, aneurysm occlusion status, and modified Rankin scale score were analyzed 1 day after treatment and in the short- (<6 months), mid- (<24 months), and long-term (>24 months) follow-up periods.

RESULTS

Forty-one cases of wide-neck aneurysms were analyzed in this study. Overall, 78.8% of the aneurysms had complete occlusion in the last follow-up, and 19.5% required retreatment with additional endovascular devices. A good clinical outcome (modified Rankin scale: 0-2) was obtained in 95.1% of the patients, and the overall treatment-related morbidity and mortality rates were 2.4% and 0.0%, respectively. The mean follow-up time was 15.3 ± 13.5 months.

CONCLUSIONS

The results obtained in this study suggest that treatment of wide-neck bifurcation aneurysms with a WEB device is feasible with an acceptable safety and efficacy rate.

The Contour-Early Human Experience of a Novel Aneurysm Occlusion Device

BACKGROUND AND PURPOSE

Endosaccular flow disruption is a recognized treatment options for treating both unruptured and ruptured aneurysms. The Contour device is designed to target the neck of an aneurysm and cause flow disruption within the aneurysm hence promoting thrombosis and neo-endothelialization at the neck. This article presents initial experiences with the Contour.

METHODS

The prospectively maintained database was retrospectively reviewed to identify patients treated with the Contour device. Demographic data, aneurysm characteristics, clinical result, and clinical and radiological follow-up information were recorded.

RESULTS

The review identified 3 patients (2 female), with 3 unruptured aneurysms, of average age 67 ± 8.7 years (range 62-77 years). The aneurysms were all located in the anterior circulation including one pericallosal, one at the A1-2 junction and one on the ICA bifurcation. The mean average dome height was 7.6 ± 0.62 mm (range 7.1-8.3 mm), dome width 5.7 ± 2 mm (range 3.5-7.5 mm), and neck width 3.6 ± 0.95 mm (range 2.5-4.2 mm). At follow-up angiography two of the aneurysms were completely occluded and one device had displaced into the aneurysm sac due to inappropriate positioning of the device. Of the patients one had minor stroke during the postoperative period but returned to baseline neurology. All patients were mRS 0 at last follow-up.

CONCLUSION

The Contour is a promising new aneurysm occlusion device. Further studies with longer term follow-up are required to determine the efficacy of this novel device.

The p48MW Flow Diverter-Initial Human Experience

Background and Purpose

The use of flow diverters to treat aneurysms arising from small caliber parent vessels has been reported. This article reports the results of the first in experiences with the p48MW (p48 Movable Wire) in humans, a device specifically designed to target vessels 1.75–3 mm in diameter.

Methods

This monocentric study retrospectively reviewed the prospectively maintained database to identify all patients treated with the p48MW device between January 2017 and January 2019 at this institution. Patient demographics, aneurysm characteristics, angiographic and clinical follow-up were recorded as well as complications.

Results

A total of 25 patients (20 female) with an average age of 55 ± 12.9 years (range 34–84) with 25 aneurysms were identified. The majority of the aneurysms was located in the anterior circulation (19/25, 76%). The average aneurysm dome width was 3.98 ± 3.6 mm (range 1.2–13 mm). Complete occlusion was seen in 18/24 (75%) aneurysms with neck remnants in 1/24 (4.2%) and continued aneurysm filling seen in the remaining cases (5/24, 20.8%). Adequate occlusion was seen in 79.2% of aneurysms (Raymond Roy Classification [RRC] grade I or II) during the follow-up period. There was a single technical complication with inappropriate deployment of the first p48MW. There was a single clinical complication (4%); however, the patient made a complete recovery (modified Rankin Scale [mRS] 0) and one patient died secondary to uncontrollable status epilepticus following acute subarachnoid hemorrhage unrelated to the treatment.

Conclusion

The p48MW is safe and effective for the treatment of aneurysms including those arising from distal vessels.

Analysis of Flow Dynamics and Outcomes of Cerebral Aneurysms Treated with Intrasaccular Flow-Diverting Devices

BACKGROUND AND PURPOSE

Intrasaccular flow diversion offers a promising treatment option for complex bifurcation aneurysms. The purpose of this study was to compare the flow conditions between successfully occluded and incompletely occluded aneurysms treated with intrasaccular devices.

MATERIALS AND METHODS

The hemodynamics in 18 completely occluded aneurysms after treatment with intrasaccular devices was compared against 18 that were incompletely occluded at follow-up. Hemodynamic and geometric parameters were obtained from computational fluid dynamics models constructed from 3D angiographies. Models of the intrasaccular devices were created and interactively deployed within the vascular models using posttreatment angiography images for guidance. Hemodynamic and geometric variables were compared using the Mann-Whitney test and univariate logistic regression analysis.

RESULTS

Incomplete occlusion was associated with large posttreatment mean aneurysm inflows (P = .02) and small reductions in the mean inflow rate (P = .01) and inflow concentration index (P = .03). Incompletely occluded aneurysms were larger (P = .002) and had wider necks (P = .004) than completely occluded aneurysms and tended to have more complex flow patterns, though this trend was not significant after adjusting for multiple testing.

CONCLUSIONS

The outcome of cerebral aneurysm treatment with intrasaccular flow diverters is associated with flow conditions created immediately after device implantation. Flow conditions unfavorable for immediate and complete occlusion seem to be created by improper positioning or orientation of the device. Complete occlusion is more difficult to achieve in larger aneurysms, aneurysms with wider necks, and aneurysms with stronger and more complex flows.

Treatment of Unruptured, Tandem Aneurysms of the ICA with a Single Flow Diverter

BACKGROUND AND PURPOSE

Intracranial adjacent tandem lesions of the internal carotid artery (ICA) are rare and the optimal treatment strategy is unknown. This study was carried out to determine whether a single flow diverter stent (FDS) could be successfully used to treat these lesions.

METHODS

The prospectively maintained database was retrospectively carried out to identify patients treated between February 2009 and February 2018 with multiple unruptured, tandem ICA aneurysms and treated with a single FDS. Demographic data, clinical presentation, aneurysm characteristics, treatment data, clinical result and clinical and radiological follow-up information were recorded.

RESULTS

A total of 69 patients (62 female, 89.8%) with average age 55 ± 14.8 years were identified. In total there were 169 aneurysms and the majority of patients (n = 47, 68.1%) had only 2 tandem aneurysms. The largest aneurysms measured 7.69 ± 5.3 mm (range 1.5-26 mm) in height, 6.64 ± 4.71 mm (range 1.5-23 mm) in width and the smaller aneurysm measured 2.61 ± 1.32 mm (range 0.8-9.5 mm) in height and 2.32 ± 1.12 mm (range 0.7-8 mm) in width. In 36 patients the p64 was used, the PED in 28 patients and Surpass in 5 patients. Follow-up was available in 54 patients (130 aneurysms). At initial follow-up (7.2 ± 4.2 months) 45 (83.3%) of the larger aneurysms and 66 (86.8%) of the smaller aneurysms were satisfactorily occluded (Raymond-Roy classification RRC 1 or 2). At delayed follow-up (18 ± 14.6 months) 48 of the larger aneurysms (88.9%) and 71 of the smaller aneurysms (93.4%) were satisfactorily occluded. There were three complications including one death.

CONCLUSION

A single FDS can be used to successfully treat multiple tandem aneurysms of the ICA with a high rate of aneurysm exclusion and an acceptable risk profile.

Treatment of Wide-Necked Bifurcation Aneurysms : Initial Results with the pCANvas Neck Bridging Device

Background

Recently, numerous devices dedicated to the treatment of wide-necked aneurysms have become available. We present our initial experience with the pCANvas device and present the technical success rate, clinical outcome and immediate angiographic occlusion rates.

Objective

We sought to determine the efficacy of flow with the pCANvas for the treatment of unruptured intracranial aneurysms.

Methods

We performed a retrospective review of our prospectively collected data to identify patients treated with the pCANvas device between February 2015 and February 2017. The patient demographics, aneurysm characteristics, immediate and delayed clinical and radiographic follow-up data were recorded.

Results

We identified 17 patients (13 female) treated only with the pCANvas device. The average age of the patients was 60.5 ± 13.3 years (range 25–75 years). The average dome width was 7.6 ± 3.2 mm (range 3–15.8 mm), dome height 7.1 ± 3.2 mm (range 3–12.9 mm) and neck width 5.4 ± 3.2 (range 3–16.3 mm). The average aspect ratio was 1.5 ± 0.8 (range 0.6–3.7). At the end of the procedure 15 aneurysms continued complete filling of the aneurysm (Raymond Roy Classification[RRC] 3) with 2 aneurysms showing only filling of the neck of the aneurysm (RRC 2). Early follow-up angiography was available for 16 patients and at this stage 11 aneurysms showed persistent and complete filling of the aneurysm (RRC 3), 5 aneurysms showed complete occlusion of the aneurysm (RRC 1) and 7 aneurysms underwent repeat treatment with coiling.

Conclusion

The early results on the use of the pCANvas are promising; however, longer term follow-up and larger studies are required.

Endovascular occlusion of pial arteriovenous macrofistulae, using pCANvas1 and adenosine-induced asystole to control nBCA injection

Background In large-caliber pial macrofistulae (pMF), the combination of high blood flow velocity and large efferent artery diameter makes control over the endovascular vessel occlusion difficult and may result in the inadvertent venous passage of occlusive devices or embolic agents. Case descriptions Patient 1: A 27-year-old man presented with headache and ataxia. An infratentorial pMF supplied by both superior cerebellar arteries with venous ectasia was found. The first treatment attempt using balloons and coils failed since the position of either device could not be controlled because of a distal diameter of the feeding artery of 8 mm. In a second session a pCANvas1 (phenox) was deployed at the level of the arteriovenous connection and adenosine-induced asystole allowed the controlled injection of nBCA/Lipiodol with partial occlusion of the pMF. A remaining arteriovenous shunt was occluded under asystole in a third session. The procedures were well tolerated, the patient returned to normal and DSA confirmed the occlusion of the fistula. Patient 2: A 13-year-old boy with hereditary hemorrhagic teleangiectasia presented with an intracerebral hemorrhage from an aneurysm of the left MCA. Twelve weeks after the aneurysm treatment a feeding MCA branch (diameter 4.5 mm) of a right frontal pMF was catheterized. The macrofistula was occluded by deployment of a pCANvas1, followed by the injection of nBCAl/Lipiodol under adenosine-induced asystole. Conclusion pCANvas1 and adenosine-induced asystole allow a controlled injection of nBCA/Lipiodol for the endovascular occlusion of high-flow pMF without venous passage of the embolic agent.