Comparison of PED and FRED flow diverters for posterior circulation aneurysms: a propensity score matched cohort study.

BACKGROUND: Flow diversion is a common endovascular treatment for cerebral aneurysms, but studies comparing different types of flow diverters are scarce. OBJECTIVE: To perform a propensity score matched cohort study comparing the Pipeline Embolization Device (PED) and Flow Redirection Intraluminal Device (FRED) for posterior circulation aneurysms. METHODS: Consecutive aneurysms of the posterior circulation treated at 25 neurovascular centers with either PED or FRED were collected. Propensity score matching was used to control for age, duration of follow-up imaging, adjunctive coiling, and aneurysm location, size, and morphology; previously ruptured aneurysms were excluded. The two devices were compared for the following outcomes: procedural complications, aneurysm occlusion, and functional outcome. RESULTS: A total of 375 aneurysms of the posterior circulation were treated in 369 patients. The PED was used in 285 (77.2%) and FRED in 84 (22.8%) procedures. Aneurysms treated with the PED were more commonly fusiform and larger than those treated with FRED. To account for these important differences, propensity score matching was performed resulting in 33 PED and FRED unruptured aneurysm pairs. No differences were found in occlusion status and neurologic thromboembolic or hemorrhagic complications between the two devices. The proportion of patients with favorable functional outcome was higher with FRED (100% vs 87.9%, p=0.04). CONCLUSION: Comparative analysis of PED and FRED for the treatment of unruptured posterior circulation aneurysms did not identify significant differences in aneurysm occlusion or neurologic complications. Variations in functional outcomes warrant additional investigations.

Carotid Calcium Volume and Stenosis after Stent Implantation.

INTRODUCTION: Internal carotid artery (ICA) stenosis could be treated with stent placement. It was hypothesized that calcium amount could be predictive of vessel stenosis after stent placement. We utilised computed tomography (CT) angiography to quantify volume of calcium material in bulbar ICA. MATERIALS AND METHODS: 28 patients with 31 treated ICA stenosis were collected and analysed using CT angiography-based calcium volume measurement. The Casper stent system (CSS) was used exclusively. Prospective data on emergent carotid stenosis were collected using serial ultrasound controls over a 12-month period. RESULTS: Median age was 76 years (interquartile range (IQR) 67.5-77.8) and the majority were men (71.4%). Plaque median calcium volume was 0.142 cm3 (IQR 0.030 - 0.227) and median average Hounsfield Units (HU) were 561.0 (414.5-675.0). We detected positive linear relationship between average HU and ICA calcium volume. Furthermore, weak positive correlation was observed between calcium volume and residual stenosis as seen on post-interventional angiography, (correlation coefficient R = 0.38, p=0.035). Stronger positive correlation emerged between plaques' average HU and residual stenosis (R = 0.42, p=0.018). Angiographic stenosis showed univariate association with late stenosis as detected 12 months after CAS. CONCLUSION: Calcium burden could be associated with residual stenosis after CSS placement. Larger studies are needed to confirm our preliminary data.

Experience With the Pipeline Embolization Device for Posterior Circulations Aneurysms: A Multicenter Cohort Study.

BACKGROUND: The Pipeline Embolization Device (PED; Medtronic) has been used off-label for the treatment of challenging posterior circulation aneurysms. Data on this modality are primarily limited to small retrospective single-center series. OBJECTIVE: To assess safety and efficacy of this treatment by establishing an international, multicenter collaboration. METHODS: Consecutive posterior circulation aneurysms treated with the PED from 2012 to 2019 across 11 neurovascular centers were retrospectively reviewed. Baseline demographics, aneurysm and treatment characteristics, complications, occlusion status, and functional outcome were assessed. RESULTS: There were 149 posterior circulation aneurysms treated with PED in 146 patients. A total of 24 (16.4%) patients presented with subarachnoid hemorrhage. Most aneurysms were dissecting/blister (36.2%) in morphology, followed by saccular (35.6%) and fusiform (28.2%). The most common locations were the vertebral (51.7%) and basilar arteries (22.8%). Complete or near-complete occlusion (>90%) was achieved in 90.9% of aneurysms at a median follow-up of 12 mo. Dissecting/blister aneurysms were most likely to occlude (P = .06). Symptomatic neurologic complications occurred in 9.4% of aneurysms, associated with larger size, ruptured presentation, presentations with brain stem compression, cranial nerve palsy, or stroke. Favorable functional outcome (modified Rankin Score 0-2) was achieved in 86.2% of patients. There were 6 fatalities of which 4 occurred in aneurysmal subarachnoid hemorrhage patients. CONCLUSION: This multicenter study shows that PED for the treatment of posterior circulation is preferentially used for the treatment of fusiform and dissecting/blister aneurysm morphologies. Despite the challenges presented by these less-common morphologies, flow diversion may be performed with a neurologic complication rate of about 10% and favorable long-term aneurysm occlusion rates.

Severe Leukoaraiosis Is Associated with Poor Outcome after Successful Recanalization of M1 Middle Cerebral Artery Occlusion Strokes.

BACKGROUND: Severe leukoaraiosis (LA) is an established risk factor for poor outcome after mechanical thrombectomy (MT) for large vessel occlusion stroke. There is uncertainty whether this association also applies to successfully recanalized patients with M1 segment middle cerebral artery (MCA) occlusions. METHODS: A retrospective single-centre study of patients with successful reperfusion (thrombolysis in cerebral infarction, TICI 2b or 3) after MT for an M1 MCA occlusion was performed over a 7-year period. LA score (LAS) was assessed using the age-related white matter change scale on pre-interventional brain imaging. RESULTS: A total of 209 patients (median age 75.0 years) were included. LAS was assessed on pre-interventional imaging by computed tomography in 177 (84.7%) patients and magnetic resonance imaging in 32 (15.3%) patients. The median LAS was 1 (IQR 0-8), and severe LA consisted of the top 25 percentile, ranging from 9 to 24. Multivariable analysis demonstrated an association of severe LA (OR 0.32, 95% CI 0.12-0.88, p = 0.023), higher NIHSS on admission (OR 0.89, 95% CI 0.84-0.94, p < 0.001), advanced age (OR 0.97, 95% CI 0.95-1.00, p = 0.039), good leptomeningeal collaterals (OR 3.65, 95% CI 1.46-8.15, p = 0.001), and TICI 3 score (OR 3.26, 95% CI 10.52-7.01) with good clinical outcome after 3 months as measured with the modified Rankin scale. CONCLUSION: Severe LA is associated with poor clinical outcome at 3 months in acute stroke patients undergoing MT due to emergent M1 MCA occlusion.

Microsurgical clipping and endovascular treatment of middle cerebral artery aneurysms in an interdisciplinary treatment concept: Comparison of long-term results.

OBJECTIVE: Treatment of middle cerebral artery (MCA) aneurysms has been historically considered as the almost exclusive domain of microsurgical clipping. This retrospective single-center study assesses whether microsurgical clipping or endovascular treatment (i.e. coiling and/or stenting) for MCA aneurysms yielded better occlusion rates and clinical outcome. METHODS: We identified patients with a minimum clinical follow-up of 12 months who had undergone MCA aneurysm repair either by clipping or by endovascular treatment between 2005 and 2015. Aneurysm occlusion rates were assessed by the Raymond-Roy Occlusion Classification (RROC) and patients' clinical outcome was measured by the modified Rankin Scale (mRS). All patients had been treated in an interdisciplinary treatment concept at a large neurovascular center; both treatment modalities were available at all times. RESULTS: Ninety-two eligible patients with MCA aneurysms, of whom 21.7% patients were treated for subarachnoid hemorrhages, were included; 38 patients underwent endovascular therapy and 54 clipping. The median age at treatment was 53.5 years (range, 25-79 years) and the median clinical follow-up was 98.5 months (range, 18-213 months). Occlusion rates were significantly higher in the clipping cohort (RROC = 1: 96.3% vs 78.9%; p = 0.04), long-term clinical outcome was better in the endovascular treatment cohort (mRS ≤ 1: 100.0% vs 90.8%; p < 0.01). Permanent treatment-associated morbidity was seen more commonly in the clipping cohort (9.3% vs 0.0%). CONCLUSIONS: Both treatment modalities are associated with excellent clinical and radiological outcome if applied within an interdisciplinary treatment concept. Endovascular aneurysm repair appears to be an attractive treatment alternative compared to clipping with low complication rates for well-selected patients.

Acute treatment of stroke due to spontaneous calcified cerebral emboli causing large vessel occlusion.

INTRODUCTION: Calcified cerebral emboli (CCE) are rarely responsible for large vessel occlusion (LVO) in acute anterior stroke, and therefore therapeutic experience is scarce. We sought to expand current knowledge upon therapeutic options with three new cases and a review of current literature. METHODS: Systematic search of patients with acute anterior stroke due to LVO in one comprehensive stroke center throughout a 4 year period. Literature search for reported cases of CCE. RESULTS: In total, 21 cases (19 found in literature and 3 from our institution) are reported with a median age of 72 years (interquartile range [IQR] 63-80). Eleven patients were treated acutely, 4 of them with endovascular thrombectomy (EVT). Middle cerebral artery (MCA) M1 was the most affected segment and large artery atherosclerosis (LAA) and cardioembolism (CE) was causative in 41% of cases. EVT was significantly superior to intravenous recombinant tissue plasminogen activator (rtPA) at p = .048 (Fisher's exact test, chi square 6.7). CONCLUSIONS: Given the small sample reported in literature and no reported randomised studies, definitive recommendations could not be reached. However, considering thrombus composition, thrombolysis is most probably not sufficient and priority should be given to EVT.