Background It has been amply demonstrated that endovascular procedures can be successful treatment for stroke, both in terms of revascularization and clinical outcome. There is not, however, a published comparison of any histological or ultrastructural damage to the vessels that may be caused by a direct aspiration first pass technique (ADAPT) or stent retrievers (SR) used in these procedures. This study analyses and compares acute damage to the arterial wall caused by ADAPT or SR. Material and methods Damage to the walls of swine extracranial arteries was evaluated after ADAPT with the Penumbra system or thrombectomy with an SR (Solitaire 6×30). The procedures were performed after injecting thrombi into the selected arteries (arteries with diameters similar to those of the human internal carotid artery and first segment of the middle cerebral artery). After the procedures, the animal was euthanized and 12 arterial samples were obtained for analysis by optical and electronic microscopy. Results Tissue samples from the vessels treated with SR showed almost complete loss of endothelium, thickening of the internal elastic lamina, and degeneration of the elastic fibers of the bordering lamina media and adventitia. In contrast, tissue samples of the vessels treated with ADAPT had a clear integral internal elastic lamina and uninterrupted endothelial lining, although cell alignment was altered and there were surface lacerations due to manipulation of the samples. Conclusions Both techniques caused acute damage to the vessel walls, however, thrombectomy with SR appeared to be more harmful to all layers of the arterial wall, particularly the endothelium.

BACKGROUND AND PURPOSE: Blister-like aneurysms are uncommon but challenging lesions. Their small size and atypical location often make the diagnosis difficult. Microsurgery and endovascular procedures have been used for their treatment, but there is no consensus on the best treatment technique. We conducted a systematic review and meta-analysis of treatments and outcomes of these vascular lesions. MATERIALS AND METHODS: We reviewed English-language articles on “blood blister-like aneurysms” published between January 1997 and November 2014. All studies reporting patients with these aneurysms treated with surgery, endovascular procedures, or combined therapy with data on treatment modalities and clinical and/or angiographic outcomes were selected, including case reports and series. We performed a meta-analysis on the 2 largest treatment groups (surgery and endovascular management). RESULTS: Sixty studies with 334 patients met our inclusion criteria. Surgery was performed in 114 patients (34.2%), and endovascular treatment, in 199 patients (59.5%). A combined treatment was used in 19 patients (5.7%). A favorable outcome (mRS 0–2) was reported in 67.4% and 78.9% of patients treated with surgery and with endovascular therapy, respectively (P = .034). CONCLUSIONS: Blister-like aneurysms are challenging vascular lesions. The choice of treatment method must be based on the initial clinical presentation and an analysis of the radiologic features of the lesion to select the best technique. Endovascular treatment seems to have lower morbidity and mortality and provides a better outcome compared with surgical approaches. Further prospective studies must be performed to confirm such interesting results.

Background and Purpose—: As a reliable scoring system to detect the risk of symptomatic intracerebral hemorrhage after thrombectomy for ischemic stroke is not yet available, we developed a nomogram for predicting symptomatic intracerebral hemorrhage in patients with large vessel occlusion in the anterior circulation who received bridging of thrombectomy with intravenous thrombolysis (training set), and to validate the model by using a cohort of patients treated with direct thrombectomy (test set). Methods—: We conducted a cohort study on prospectively collected data from 3714 patients enrolled in the IER (Italian Registry of Endovascular Stroke Treatment in Acute Stroke). Symptomatic intracerebral hemorrhage was defined as any type of intracerebral hemorrhage with increase of ≥4 National Institutes of Health Stroke Scale score points from baseline ≤24 hours or death. Based on multivariate logistic models, the nomogram was generated. We assessed the discriminative performance by using the area under the receiver operating characteristic curve. Results—: National Institutes of Health Stroke Scale score, onset-to-end procedure time, age, unsuccessful recanalization, and Careggi collateral score composed the IER-SICH nomogram. After removing Careggi collateral score from the first model, a second model including Alberta Stroke Program Early CT Score was developed. The area under the receiver operating characteristic curve of the IER-SICH nomogram was 0.778 in the training set (n=492) and 0.709 in the test set (n=399). The area under the receiver operating characteristic curve of the second model was 0.733 in the training set (n=988) and 0.685 in the test set (n=779). Conclusions—: The IER-SICH nomogram is the first model developed and validated for predicting symptomatic intracerebral hemorrhage after thrombectomy. It may provide indications on early identification of patients for more or less postprocedural intensive management.

BACKGROUND: Although flow diverters (FDs) have been widely accepted by neurointerventionists, their safety has yet to be fully defined. Stratification by aneurysm size and location is essential for correct evaluation of treatment outcomes and risks of flow diversion. OBJECTIVE: To compare neurological and anatomic outcomes and evaluate the risk of complications after endovascular treatment of large or giant internal carotid artery (ICA) aneurysms with FD/FDs alone or together with coil embolization. METHODS: We reviewed all patients with large or giant, ruptured or unruptured ICA aneurysms who underwent endovascular treatment with flow diversion alone (group A) or with concomitant coiling (group B) in 4 international institutions between 2010 and 2015. Anatomic outcome was evaluated using the Byrne scale on digital subtraction angiography and/or angioMRI and/or angioCT scans 3, 6, 12, and 24 months postoperatively. RESULTS: We collected 44 patients with large or giant ICA aneurysms. Four patients (9%) presented with aneurysmal subarachnoid hemorrhage (SAH). FD/FDs were used alone in 26 patients and in combination with coil embolization in the 18 remaining patients. The mortality rate due to procedure-related and/or neurological complications was 2.2%. Twelve months after the procedure, 88.6% (n = 39) of patients had a favorable neurological outcome. One year after the procedure, the aneurysm was completely occluded in 72.7% of patients: 61.5% (16/18) in group A and 88.9% (16/26) in group B. CONCLUSION: Clinical outcomes and rates of intraoperative and postoperative complications did not differ significantly between the groups. Better anatomic results using FD/FDs combined with coils were documented 6 months after the procedure; this option seems to provide a higher aneurysm occlusion rate and reduce the need for retreatment.

Background and purpose Aspiration thrombectomy of large vessel occlusions has made a comeback among recanalization techniques thanks to recent advances in catheter technology resulting in faster recanalization and promising clinical results when used either alone or as an adjunct to stent retriever. This multicenter retrospective study reports angiographic data, complications, and clinical outcome in patients treated with aspiration thrombectomy as the first-line option. Materials and methods We analysed the clinical and procedural data of patients treated from January 2014 to March 2015. Recanalization was assessed according to the Thrombolysis in Cerebral Infarction score. Clinical outcome was evaluated at discharge and after 3 months. Results Overall, 152 patients (mean age 68 years) were treated. Sites of occlusion were 90.8% anterior circulation (including 16.4% tandem extracranial/intracranial occlusions) and 9.2% basilar artery. In 79 patients administration of intravenous tissue plasminogen activator was attempted. Recanalization of the target vessel was obtained in 115/152 cases (75.6%) whereas direct aspiration alone was successful in 83/152 cases (54.6%) with an average puncture to revascularization time of 44.67 min. Symptomatic intracranial hemorrhage occurred in 7.8% and embolization to new territories in 1.9%. 77 patients (50.6%) had a good outcome at 90-day follow-up: 55/96 in the direct aspiration alone group and 22/56 in the aspiration-stent retriever group. Conclusions Direct aspiration thrombectomy appears a feasible technique with good revascularization results achieved in more than half the patients. In light of the self-reported data, inhomogeneous patient selection, absence of a core imaging laboratory, and a non-standardized approach, the results should be validated in a larger trial.

Background Emergent carotid artery stenting (eCAS) is performed during mechanical thrombectomy for acute ischemic stroke due to tandem occlusion. However, the optimal management strategy in this setting is still unclear. Objective To carry out a systematic review and meta-analysis to investigate the safety and efficacy of eCAS in patients with tandem occlusion. Methods Systematic review followed the PRISMA guidelines. Medline, EMBASE, and Scopus were searched from January 1, 2004 to March 7, 2022 for studies evaluating eCAS and no-stenting approach in patients with stroke with tandem occlusion. Primary endpoint was the 90-day modified Rankin Scale score 0–2; secondary outcomes were (1) symptomatic intracerebral hemorrhage (sICH), (2) recurrent stroke, (3) successful recanalization (Thrombolysis in Cerebral Infarction score 2b–3), (4) embolization in new territories, and (5) restenosis rate. Meta-analysis was performed using the Mantel-Haenszel method and random-effects modeling. Results Forty-six studies reached synthesis. eCAS was associated with higher good functional outcome compared with the no-stenting approach (OR=1.52, 95% CI 1.19 to 1.95), despite a significantly increased risk of sICH (OR=1.97, 95% CI 1.23 to 3.15), and higher successful recanalization rate (OR=1.91, 95% CI 1.29 to 2.85). Restenosis rate was lower in the eCAS group than in the no-stenting group (2% vs 9%, p=0.001). Recanalization rate was higher in retrograde than antegrade eCAS (OR=0.51, 95% CI 0.28 to 0.93). Intraprocedural antiplatelets during eCAS were associated with higher rate of good functional outcome (60% vs 46%, p=0.016) and lower rate of sICH (7% vs 11%; p=0.08) compared with glycoprotein IIb/IIIa inhibitors. Conclusions In observational studies, eCAS seems to be associated with higher good functional outcome than no-stenting in patients with acute ischemic stroke due to tandem occlusion, despite the higher risk of sICH. Dedicated trials are needed to confirm these results.