Vessel wall imaging with advanced flow suppression in the characterization of intracranial aneurysms following flow diversion with Pipeline embolization device

BackgroundHigh-resolution vessel wall MRI (VWI) is increasingly used to characterize intramural disorders of the intracranial vasculature unseen by conventional arteriography.ObjectiveTo evaluate the use of VWI for surveillance of flow diverter (FD) treated aneurysms.Materials and methodsRetrospective study of 28 aneurysms (in 21 patients) treated with a FD (mean 57 years; 14 female). All examinations included VWI and a contemporaneously obtained digital subtraction angiogram. Multiplanar pre- and post-gadolinium 3D, variable flip-angle T1 black-blood VWI was obtained using delay alternating nutation for tailored excitation (DANTE) at 3T. 3D time-of-flight MR angiography (MRA) was also carried out. Images were assessed for in-stent stenosis, aneurysm occlusion, presence and pattern/distribution of aneurysmal or parent vessel gadolinium enhancement.ResultsThe VWI-MRI was performed on average at 361±259 days after the intervention. Follow-up DSA was performed at 338±254 days postintervention. Good or excellent black-blood angiographic quality was recorded in 22/28 (79%) pre-contrast and 21/28 (75%) post-contrast VWI, with no cases excluded for image quality. Aneurysm enhancement was noted in 24/28 (85.7%) aneurysms, including in 79% of angiographically occluded aneurysms and 100% of angiographically non-occluded aneurysms. Enhancement of the stented parent-vessel wall occurred significantly more often when aneurysm enhancement was present (92% vs 33%, p=0.049).ConclusionAdvanced VWI produces excellent depiction of FD-treated aneurysms, with robust evaluation of the parent vessel and aneurysm wall to an extent not achievable with conventional MRI/MRA. Gadolinium enhancement may, however, continue even after enduring catheter angiographic occlusion, confounding interpretation, and requiring cognizance of this potentially prolonged effect in such patients.

Endovascular Therapy of 103 Aneurysms in the Internal Carotid Artery with Flow Re-Direction Endoluminal Device

Objective Intracranial aneurysms (AIs) are acquired vascular abnormalities that cause sacculations in the arterial wall and are present in ∼2 to 5% of the population. Among the treatment options are endovascular interventions with the use of flow-redirecting stents. In the present study, we analyzed the flow re-direction endoluminal device (FRED). Methods The present study aims to describe the results obtained from treatment with FRED in a series of patients affected by aneurysms in intracranial segments of the internal carotid artery. This is a cross-sectional, epidemiological, and observational study, whose data were obtained from the medical records of 81 patients from July 2018 to July 2019. Results One hundred and three internal carotid artery aneurysms were observed in 81 patients, with a prevalence of women (91.35%), small (< 10 mm) (89.33%), and located at the C6 level (73.78%) of the internal carotid artery. Of the 81 patients, 16 had multiple aneurysms in the same artery. One hundred and three FRED stents were used in the treatment. These patients underwent angiography 6 months after the surgery, using the O'Kelly-Marotta classification (OKM) to assess the effectiveness of the device, and it was observed that: in 91 of the 103 procedures (88.34%), the FRED was fully open and well positioned, thus restoring the arterial flow and leading to a statistically significant result. In addition, a low complication rate (4.85%) was found, with ischemic stroke being the main complication (1.94%). Conclusion This device can be an effective option in the treatment of internal carotid aneurysms since the aneurysm occlusion rate is excellent with a low rate of complications.

Flow diversion for internal carotid artery aneurysms with compressive neuro-ophthalmologic symptoms: clinical and anatomical results in an international multicenter study

BackgroundScientific data on the safety and efficacy of flow diverter stents (FDS) for the treatment of unruptured internal carotid artery (ICA) aneurysms with compressive neuro-ophthalmological symptoms are scarce. We studied this subject in a retrospective international multicenter series, pooling data of 9 tertiary care neurointerventional departments.ObjectiveTo investigate, in a retrospective, multicentric cohort of patients presenting with visual or oculomotor symptoms attributed to a compressive carotid artery in an unruptured intracranial aneurysm, the safety and efficacy profiles of FDS, by analyzing neuro-opthalmologic symptom evolution following FDS placement, complications, and aneurysm obliteration rates.MethodsAll patients treated since 2015 with a FDS for an unruptured aneurysm of the ICA with signs of compressive cranial nerve symptoms (CN II, III, IV, VI) were included.ResultsWe treated 55 patients with 55 aneurysms; 21 (38.2%) patients had oculomotor and 15 (27.3%) visual symptoms only; 19 (34.5%) presented with a combination of both. Treatment-related morbidity/mortality occurred in 7.2% and 3.6%, respectively. At last imaging follow-up (13.1±10.5 months) rates of complete aneurysm occlusion, neck remnant, and aneurysm remnant were 72%, 14%, and 14%, respectively. At last clinical follow-up after 13±10.5 months, 19/51 (37.3%) patients had recovered completely and 18/51 (35.3%) had recovered at least partially from their neuro-ophthalmological symptoms. In multivariable models, a longer delay between symptom onset and treatment was associated with higher odds for incomplete recovery and lower odds for any improvement (aOR 1.03 (95% CI 1.01 to 1.07), p=0.047 and 0.04 (0–0.81), p=0.020). Incomplete recovery was independently associated with older age and fusiform aneurysms.ConclusionFDS are effective to treat patients with compressive aneurysms of the ICA causing neuro-ophthalmological symptoms, especially when treatment is initiated early after symptom onset, and aneurysm occlusion is adequate. However, serious complications are not rare.

Diversion-p64: results from an international, prospective, multicenter, single-arm post-market study to assess the safety and effectiveness of the p64 flow modulation device

BackgroundThe use of flow diversion to treat intracranial aneurysms has increased in recent years.ObjectiveTo assess the safety and angiographic efficacy of the p64 flow modulation device.MethodsDiversion-p64 is an international, prospective, multicenter, single-arm, study conducted at 26 centers. The p64 flow modulation device was used to treat anterior circulation aneurysms between December 2015 and January 2019. The primary safety endpoint was the incidence of major stroke or neurologic death at 3–6 months, with the primary efficacy endpoint being complete aneurysm occlusion (Raymond-Roy Occlusion Classification 1) on follow-up angiography.ResultsA total of 420 patients met the eligibility criteria and underwent treatment with the p64 flow modulation device (mean age 55±12.0 years, 86.2% female). Mean aneurysm dome width was 6.99±5.28 mm and neck width 4.47±2.28 mm. Mean number of devices implanted per patient was 1.06±0.47, with adjunctive coiling performed in 14.0% of the cases. At the second angiographic follow-up (mean 375±73 days), available for 343 patients (81.7%), complete aneurysm occlusion was seen in 287 (83.7%) patients. Safety data were available for 413 patients (98.3%) at the first follow-up (mean 145±43 days) with a composite morbidity/mortality rate of 2.42% (n=10).ConclusionsDiversion-p64 is the largest prospective study using the p64 flow modulation device. The results of this study demonstrate that the device has a high efficacy and carries a low rate of mortality and permanent morbidity.

Standalone Flow Diversion Therapy Effectively Controls Rebleeding of Acutely Ruptured Internal Carotid Artery Trunk (Nonbranching) Microaneurysms

Flow diversion is a promising option in selected patients with acutely ruptured microaneurysms. In this article, we reviewed our experience. Patients with acute spontaneous subarachnoid hemorrhage (SAH) after rupture of a blister-like or saccular microaneurysm (≤2 mm maximal diameter) at a nonbranching ICA site treated from January 2016 to June 2019 using flow diversion as standalone therapy were included in this study. An EVD was usually placed preventively. Antiplatelet effects of pre-procedure DAPT were evaluated (target PRU, 80–160). After the intervention, DAPT was continued for ≥6 months, aspirin—indefinitely. Angiographic controls were obtained. Fifteen patients (12 female; mean age, 46.4 years) with 15 ruptured ICA microaneurysms (mean diameter, 1.8 mm) were included. An EVD was placed in 12 patients (75%) before DAPT administration and stenting. PRU values immediately before FDS were 1–134 (mean, 72.1). One patient died 27 days after flow diversion due to a suspected fulminant pulmonary embolism. Aneurysms were completely occluded at the 6–12-month angiographic follow-up in 14/14 surviving patients, with no rebleeding at a mean of 14 months. Late mRS was 0–2 in 13/14 patients and 3 in one due to sequelae of the original hemorrhage. Flow diversion provided robust aneurysm rebleeding control. Angiographic follow-up confirmed complete aneurysm occlusion in all the cases.

Patient and aneurysm factors associated with aneurysm recanalization after coiling

BackgroundOne limitation of the endovascular treatment of intracranial aneurysms is aneurysm recanalization. The Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm (ARETA) study is a prospective multicenter cohort study evaluating the factors associated with recanalization after endovascular treatment.MethodsThe current analysis is focused on patients treated by coiling or balloon-assisted coiling (BAC). Postoperative, mid-term vascular imaging, and evolution of aneurysm occlusion were independently evaluated by two neuroradiologists. A 3-grade scale was used for aneurysm occlusion (complete occlusion, neck remnant, and aneurysm remnant) and for occlusion evolution (improved, stable, and worsened). Recanalization was defined as any worsening of aneurysm occlusion.ResultsBetween December 2013 and May 2015, 16 French neurointerventional departments enrolled 1289 patients. A total of 945 aneurysms in 908 patients were treated with coiling or BAC. The overall rate of aneurysm recanalization at mid-term follow-up was 29.5% (95% CI 26.6% to 32.4%): 28.9% and 30.3% in the coiling and BAC groups, respectively. In multivariate analyses factors independently associated with recanalization were current smoking (36.6% in current smokers vs 24.5% in current non-smokers (OR 1.8 (95% CI 1.3 to 2.4); p=0.0001), ruptured status (31.9% in ruptured aneurysms vs 25.1% in unruptured (OR 1.5 (95% CI 1.1 to 2.1); p=0.006), aneurysm size ≥10 mm (48.8% vs 26.5% in aneurysms <10 mm (OR 2.6 (95% CI 1.8 to 3.9); p<0.0001), wide neck (32.1% vs 25.8% in narrow neck (OR 1.5 (95% CI 1.1 to 2.1); p=0.02), and MCA location (34.3% vs 28.3% in other locations (OR 1.5 (95% CI 1.0 to 2.1); p=0.04).ConclusionsSeveral factors are identified by the ARETA study as playing a role in aneurysm recanalization after coiling: current smoking, aneurysm status (ruptured), aneurysm size (≥10 mm), neck size (wide neck), and aneurysm location (middle cerebral artery). This finding has important consequences in clinical practice.Trial registration numberURL: http://www.clinicaltrials.gov; Unique Identifier: NCT01942512.

Propensity score-adjusted analysis on stent-assisted coiling versus coiling alone for ruptured intracranial aneurysms

Stent-assisted coiling (SAC) for ruptured intracranial aneurysms (RIAs) remains controversial due to an inherent risk of potential thromboembolic and hemorrhagic complications. We compared SAC and coiling alone for the management of RIAs using propensity score-adjustment. Sixty-four patients treated by SAC and 220 by stand-alone coiling were retrospectively reviewed and compared using inverse probability of treatment weighting (IPTW) with propensity scores. Functional outcome, procedure-related and overall complications and angiographic results were analyzed. Aneurysms treated by SAC had a larger diameter, a wider neck and were more frequently located at the posterior circulation. SAC had a higher risk for thromboembolic complications (17.2% vs. 7.7%, p = 0.025), however, this difference did not persist in the IPTW analysis (OR 1.2, 95% CI 0.7–2.3, adjusted p = 0.458). In the adjusted analysis, rates of procedural cerebral infarction (p = 0.188), ventriculostomy-related hemorrhage (p = 0.584), in-hospital mortality (p = 0.786) and 6-month favorable functional outcome (p = 0.471) were not significantly different between the two groups. SAC yielded a higher complete occlusion (80.0% vs. 67.2%, OR 3.2, 95% CI 1.9–5.4, p < 0.001) and a lower recanalization rate (17.5% vs. 26.1%, OR 0.3, 95% CI 0.2–0.6, p < 0.001) than stand-alone coiling at 6-month follow-up. In conclusion, SAC of large and wide-necked RIAs provided higher aneurysm occlusion and similar clinical outcome, when compared to stand-alone coiling.

Abstract 1122‐000103: FlowDiverter:A Study Safety and Efficacy in a Consecutive Group of 53 Patient and 60 Aneurysm

Introduction : Endovascular flow diverters are increasingly used for the treatment of cerebral aneurysms. We assessed the safety and efficacy of the Flow Diverters in a consecutive series of 53 patients and 60 aneurysms. Methods : Inclusion criteria were wide‐neck, blister‐like, or fusiform aneurysms independent of size, treated with the FRED, PIPELINE and SILK between December 2014 and Junho 2021. Assessment criteria were aneurysm occlusion, manifest ischemic stroke, bleeding, or death. The occlusion rate was assessed at 6 months and 1 year with DSA by using the Raymond classification and the O'Kelly‐Marotta grading scale. Results : Fifty three patients (mean age 54.3 years;81.1% female) with 60 aneurysms were treated with 9 Silk, 38 FREDs and 13 Pipeline. Aneurysm size ranged from 2.5 to 30 mm. Deployment of the Flow diverters was successful in 52 aneurysms. Three patient developed mild stroke symptoms that fully receded within days, 4 patients occlusion total carotid because resistant antiagregation and another patient’s development Swelling syndrome. There has been one death. Initial follow‐up at 6 months showed complete occlusion in 90% of the overall study group and 93,33% at 1 year. Conclusions : The flow diverter is a safe device for the treatment of cerebral aneurysms of various types. Our data reveal high occlusion rates at 6 months and 1 year. Long‐term occlusion rates are expected.

P.193 Competitive Flow Diversion: Proposed Classification System

Background: Competitive flow diversion (CFD) is a novel application of flow diversion stenting (FDS), redirecting flow into a normal artery proximal or distal to the aneurysmal parent artery. A classification system for CFD has not been previously reported. Methods: Report of operative technique and novel classification system for CFD. Results: A patient with subarachnoid haemorrhage and three aneurysms arising from the Pcomm-P1 complex, was treated with endovascular coiling and CFD. The PCOM aneurysm was coiled. Two aneurysms arose from the distal right P1- PCA. After a failed attempt to treat with FDS across the P1-PCA, the P1-aneurysms were successfully treated with CFD distal to the P1-PCA, from Pcomm to P2. Over 12 months, CFD redirected flow via ICA-Pcomm-P2, reducing the size of the P1-PCA, obliterating the P1-aneurysms. Herein, we classify competitive flow diversion into two types. Type I CFD is when the parent artery harbouring the aneurysm is “jailed” proximally. Type II CFD occurs when flow is diverted from the parent artery distal to the aneurysm origin. Conclusions: Herein, we propose a novel classification for CFD. We describe the first case of aneurysm occlusion in the circle of Willis with Type II CFD, and use of CFD for the treatment of multiple adjacent aneurysms.