Pipeline embolization device retraction and foreshortening after internal carotid artery blister aneurysm treatment

Early Outcomes of the Pipeline Vantage Flow Diverter : A Multicentre Study

PURPOSE

The recently introduced Pipeline Vantage Embolization Device with Shield Technology is the fourth generation of Pipeline flow diverter devices. Due to the relatively high rate of intraprocedural technical complications, modifications were subsequently made to the device after a limited release of the device in 2020. This study aimed to evaluate the safety and efficacy of the modified version of this device.

METHODS

This was a multicentre retrospective series. The primary efficacy endpoint was aneurysm occlusion in the absence of retreatment. The primary safety endpoint was any neurological morbidity or death. Ruptured and unruptured aneurysms were included in the study.

RESULTS

A total of 52 procedures were performed for 60 target aneurysms. Treatment was performed on 5 patients with ruptured aneurysms. The technical success rate was 98%. The mean clinical follow-up time was 5.5 months. In patients presenting with unruptured aneurysms there were no deaths, 3 (6.4%) major complications and 7 (13%) minor complications. In the five patients presenting with subarachnoid haemorrhage there were 2 (40%) major complications with 1 (20%) of these resulting in death, and 1 (20%) minor complication. Of the patients 29 (56%) had undergone 6‑monthly postprocedural angiographic imaging with a mean time of 6.6 months demonstrating that 83% of patients had achieved adequate occlusion (RROC1/2) of the aneurysm.

CONCLUSIONS

In this non-industry-sponsored study, the occlusion rates and safety outcomes were similar to those seen in previously published studies with flow diverter devices and earlier generation Pipeline devices. Modifications to the device appear to have improved ease of deployment.

Verification of software-based preoperative simulation of flow diverters in clinical cases

OBJECTIVE

The authors sought to verify the use of a preoperative simulation software for the treatment of intracranial aneurysms using flow diverters (FDs) based on three-dimensional rotational angiography (3DRA) data.

METHODS

Based on 3DRA data, the preoperative simulation software (UKNOW) was used to simulate the deployment of virtual FDs. The length and dimensions of virtual and real devices were compared. The deployment plan recommended by the UKNOW software was preliminarily used to complete implantations in the real world. During the experiment, experienced neurointerventional experts were responsible for supervising and judging information such as the length, dimension, and deployment location of the FDs.

RESULTS

This study retrospectively analyzed the data of 29 patients who received FD treatment. There was no statistical difference between the length of the real device and the virtual device (p = 0.6). The dimensions of FDs recommended by the software were consistent with the dimensions used in 24 out of the 29 real cases. In four of the remaining five cases, neurointerventional experts found that the FD dimensions recommended by the software were superior to those were actually used. Thus, the accuracy rate for FD dimension recommendations by the UKNOW software was 96.6% (28/29). Procedures performed in five cases using deployment plans recommended by the UKNOW software all achieved good postoperative results; the deployment positions of the device were reasonable, and all devices showed good wall adherence.

CONCLUSIONS

UKNOW software could accurately simulate the length and deployment position of the real FDs and provide suitable device dimensions.

Multiple Pipeline Embolization Devices for the Treatment of Complex Intracranial Aneurysm: A Multi-Center Study

Background

The Pipeline for Uncoilable or Failed Aneurysms (PUFS) trial primarily demonstrated the safety and efficacy of the implantation of multiple pipeline embolization devices (multi-PEDs) for large/giant intracranial aneurysms. However, no study has focused on when, why, or how to apply multi-PEDs.

Objective

The purpose of this study was to investigate the indications and strategies of using multi-PEDs for complex intracranial aneurysms.

Methods

Patients who had been treated with two or more PEDs were included in the post-market multicenter registry study from 2014 to 2019, across 14 centers in China. Indications, strategies, perioperative safety, and clinical outcomes were retrospectively analyzed. The modified Rankin scale (mRS) score was used to evaluate clinical outcomes comprehensively, and the O’Kelly–Marotta (OKM) grading scale was used to evaluate aneurysm healing results.

Results

A total of 55 intracranial aneurysms were treated with multi-PEDs. There were 20 fusiform aneurysms with a large range, 25 large/giant saccular aneurysms, six aneurysms with failed treatment, and four aneurysms with greatly varied diameters of the parent artery. The strategies included telescope techniques in 40 patients and overlap techniques in 15 patients. In total, 120 stents were deployed in 55 patients. The operation styles included 25 patients (55.6%) with two PEDs, 21 patients (38.2%) with two PEDs combined with coiling, four patients (7.3%) with three PEDs, four patients (7.3%) with three PEDs combined with coiling, and one patient (1.8%) with four PEDs. Angiography revealed OKM D in two, OKM C in seven, and OKM A and B in 46 cases after surgery. During the perioperative period, eight patients developed neurological dysfunction, three of whom died. A total of thirty-four patients were followed up with digital subtraction angiography for 2–45 (8.2 ± 8.0) months. Angiography revealed OKM D in 26, OKM C in five, and OKM B in three. At the last follow-up, the mRS score was 0–1 in 52 patients.

Conclusion

The treatment of anterior circulation aneurysms with multi-PEDs is safe and effective. The implantation of multi-PEDs could be considered for large-scale fusiform aneurysms, large/giant saccular aneurysms with a jet-sign, salvage of failed PED treatments, and in cases where the diameter of the parent artery varies greatly.

The 8-year single-center experience of telescoping flow diverter for complex intracranial aneurysms treatment

OBJECTIVE

Treatment of complex intracranial aneurysms (IAs) is still a challenging thing and this study aims to summarize the experience of telescoping flow diverters (FDs) in treating complex intracranial aneurysms.

METHOD

Between April 2013 to November 2020, 381 IA cases treated by flow diverters (FD) were retrieved from the database of 4988 IA cases, and finally 20 cases treated by telescoping FDs were enrolled for further analysis.

RESULT

Among 20 patients, 15 patients (75.0%) received Tubridge telescoping while 5 patients (25.0%) received PED telescoping. The technical success rate was 100%. The immediate occlusion results were: 7 cases of OKM grade A (35.0%), 11 cases of OKM grade B (55.0%), and 2 cases of OKM grade C (10.0%). No perioperative complications occurred. The clinical follow-up was available in 20 patients (100%) and the follow-up time was 6-96 months. One patient developed massive infarction and the other 19 patients were range between 0 and 2. The angiographic follow-up was available in 17 patients (85%) and the follow-up time was 6-27 months. The occlusion results were: 1 case of OKM grade B (5.9%), 6 cases of OKM grade C (35, 0.3%), and 10 cases of OKM grade D (58.8%). 2 patients (11.8%) developed occlusion of the patent artery.

CONCLUSION

Telescoping flow diverters showed low perioperative complications and high IA occlusion rate when treating complex intracranial aneurysms in follow-up time, which provides an alternative manner beyond conventional strategy for neurosurgeons.

Safety Evaluation and Flow Modification in the Anterior Cerebral Artery after Pipeline Embolization Device Deployment across the Internal Carotid Artery Terminus

Method

The clinical and imaging data of PEDs in the postmarket multicenter registry study (PLUS) in China were retrospectively analyzed, and patients were divided into two groups on the basis of the follow-up angiographic results: group 1 (no significant change in A1 blood flow) and group 2 (A1 occlusion or decreased blood flow). We collected patients' baseline data and evaluated the following imaging indicators: diameter and ratio of bilateral A1, M1, and internal carotid artery (ICA) vessels before stenting and the ratio of the PED size (sPED) to the ipsilateral ICA (I-ICA) diameter on the implantation side.

Results

A total of 1171 patients were included, of whom 48 met the inclusion criteria (17 in group 1 and 31 in group 2). In group 2, three patients experienced neurological deterioration at follow-up. From the univariate analysis of outcomes, single PED without coils, incomplete aneurysm occlusion (IAO), maximum aneurysm diameter, aneurysms involving the ICA bifurcation (ICAb), and large sPED/I-ICA diameter ratio were included in the multivariate analysis (P < 0.20). The multivariate regression analysis results showed that the ratio of sPED/I-ICA diameter was the factor influencing A1 vessel occlusion. The area under the ROC curve was 73.2%. When the sPED/I-ICA diameter ratio was 1.14, sensitivity was 70.6%, and specificity was 77.4%.

Conclusion

When an oversized PED is placed from M1 to the ICA, the higher porosity formed at the covered A1 orifice is conducive to maintaining stable A1 blood flow and reducing the risk of A1 vessel occlusion. This trial is registered with ClinicalTrials.gov identifier: NCT03831672.

Internal Carotid Artery Blister Aneurysm: Review of Endovascular Techniques

Cerebral blister aneurysms are very difficult vascular lesions in terms of accurate diagnosis as well as proper management strategy for vascular neurosurgeons and neurointerventionists. Histopathological analysis has revealed their nature to be more akin to pseudoaneurysms in comparison to the typical berry aneurysms. This explains their fragile nature, with high probability of rerupture and regrowth during the follow-up if not addressed properly. Even though surgical approaches have evolved over the years to minimize intraprocedural rupture and recurrence, they still have relatively high morbidity as well as mortality in comparison to endovascular treatment. Over the last few years, endovascular treatment has evolved significantly, with introduction of new devices and techniques. Focus of the endovascular management has shifted from the deconstructive techniques to reconstructive ones with parent artery preservation. Recent introduction of flow diverter technology has enabled neurointerventionists to manage these difficult lesions with more confidence in terms of avoiding rerupture and recurrence. Flow diverter (FD) use in blister aneurysm resulted in high-technical success, complete aneurysm occlusion, and less complications in comparison to other reconstructive techniques like simple coiling, stent assisted coiling, and overlapping/monotherapy stent placement. Few debatable issues like use of dual antiplatelets in the setting of acute subarachnoid hemorrhage (SAH), timing of drugs in relation to procedures, single/overlapping devices, and concerns during cerebral vasospasm phase need further detailed analysis and standardized protocols. In this article, we have done a review of different endovascular treatment options in the management of internal carotid artery blister aneurysms with special focus on FD and issues related to it.

Treatment of Anterior Circulation Aneurysms in the Internal Carotid Artery With Flow Diverters

Several studies have shown the efficacy and feasibility of flow diversion for the endovascular treatment of wide-necked and otherwise anatomically challenging intracranial aneurysms (IA). Technological advances have led to successful long-term occlusion rates and a safety profile for flow-diverter stents that parallels other endovascular and open surgical options for these lesions. With growing indications for use of the Pipeline Embolization Device (PED, Medtronic, Dublin, Ireland) to include IAs up to the internal carotid artery (ICA) terminus, understanding the nuances of this technology is increasingly relevant. Furthermore, there is a growing body of literature on the use of flow diversion to treat distal (up to A2, M2, and P2), ruptured, and posterior circulation aneurysms, although these applications are "off-label" at present. In this manuscript, we discuss the expanding role of flow diversion in the ICA and compare this technique with other endovascular options for the treatment of ICA IAs. We also discuss technical nuances of the deployment of flow diverters for the treatment of challenging lesions and in difficult and tortuous anatomy.

Flow diverters for ruptured posterior circulation perforator aneurysms: multicenter experience and literature review

BACKGROUND

The management of ruptured posterior circulation perforator aneurysms (rPCPAs) remains unclear. We present our experience in treating rPCPAs with flow diverter stents (FDs) and evaluate their safety and efficacy at mid- to long-term follow-up. A diagnostic and therapeutic algorithm for rPCPAs is also proposed.

METHODS

We retrospectively analyzed data from all consecutive patients with rPCPAs treated with FDs at our institutions between January 2013 and July 2019. Clinical presentations, time of treatments, intra- and perioperative complications, and clinical and angiographic outcomes were recorded, with a mid- to long-term follow-up. A systematic review of the literature on rPCPAs treated with FDs was also performed.

RESULTS

Seven patients with seven rPCPAs were treated with FDs. All patients presented with an atypical subarachnoid hemorrhage distribution and a low to medium Hunt-Hess grade. In 29% of cases rPCPAs were identified on the initial angiogram. In 57% of cases, FDs were inserted within 2 days of the diagnosis. Immediate aneurysm occlusion was observed in 14% of the cases and in 71% at the first follow-up (mean 2.4 months). At mean follow-up of 33 months (range 3-72 months) one case of delayed ischemic complication occurred. Six patients had a modified Rankin Scale (mRS) score of 0 and one patient had an mRS score of 4 at the latest follow-up.

CONCLUSIONS

The best management for rPCPAs remains unclear, but FDs seem to have lower complication rates than other treatment options. Further studies with larger series are needed to confirm the role of FDs in rPCPA.

Hemodynamic Fate of the Precommunicating Anterior Cerebral Artery Is Predicted by Vessel Dominance After Pipeline Embolization Device Deployment Across the Internal Carotid Artery Terminus

BACKGROUND

The Pipeline embolization device (PED) is commonly used for the treatment of distal internal carotid artery (ICA) aneurysms, which often require placing the stent across the origin of the precommunicating segment of the anterior cerebral artery (ACA-A1). We sought to characterize the clinical and angiographic consequences of this maneuver.

METHODS

We performed a retrospective review of a prospectively collected database of patients treated with the PED at a single academic center from 2011 to 2017 to find patients for whom the PED was extended across the origin of the ACA-A1. The patient demographic data, pretreatment angiographic imaging findings, sizing of the bilateral A1 and ipsilateral M1 segment of the middle cerebral artery (MCA-M1), and follow-up angiographic and clinical imaging findings were recorded.

RESULTS

A total of 27 patients were included in the present study (8 men and 19 women; age, 52 ± 14.9 years). Follow-up angiography was conducted at a median of 9.2 months (interquartile range, 6; range, 5-84). The covered A1 segment was patent in 17 patients (63%). The covered ACA-A1/ipsilateral MCA-M1 ratio was 1.43 times greater for the patent ACA-A1 segments than those that were occluded (P = 0.0006). Similarly, the covered ACA-A1/contralateral ACA-A1 ratio was significantly larger statistically (1.64; P < 0.0001) for the patent ACA-A1 segments than that for those that were occluded. None of the patients developed clinical or radiographic signs of ACA stroke. The modified Rankin scale worsened for 1 patient during follow-up owing to a further decline of presenting vision loss.

CONCLUSIONS

The PED can be used to treat aneurysms with deployment from the MCA-M1 to the ICA without resulting in ACA stroke. Ipsilateral A1 segment dominance might be predictive of continued blood flow into the ACA after deployment at this location.

Very delayed discontinuation of telescoped Pipeline embolization devices: a case report

BACKGROUND

Flow diversion with the Pipeline embolization device (PED) is a widely accepted treatment modality for aneurysm occlusion. Previous reports have shown no recanalization of aneurysms on long-term follow-up once total occlusion has been achieved.

CASE DESCRIPTION

We report on a 63-year-old male who had a large internal carotid artery cavernous segment aneurysm. Treatment with PED resulted in complete occlusion of the aneurysm. However, follow-up angiography at four years revealed recurrence of the aneurysm due to disconnection of the two PEDs placed in telescoping fashion.

CONCLUSION

Herein, we present the clinico-radiological features and discuss the possible mechanisms resulting in the recanalization of aneurysms treated with flow diversion.