Sub-satisfactory stenting recanalization of severe vascular stenosis of the posterior circulation can significantly improve cerebral hemodynamic perfusion.

PURPOSE: To investigate the effect of sub-satisfactory stenting recanalization of severe vascular stenosis of the posterior circulation on cerebral hemodynamic perfusion. MATERIALS AND METHODS: Patients with severe vascular stenosis of the posterior circulation who had undergone three-dimensional cerebral angiography before and after stenting were retrospectively enrolled. Computational fluid dynamic (CFD) analysis of hemodynamic parameters at the stenosis, perforating branch, and normal arterial segments proximal and distal to the stenosis were performed. RESULTS: Sixty-two patients with basilar artery stenosis aged 60.9 ±â€¯9.6 years were enrolled, and stent angioplasty resulted in the reduction of stenosis degree from 85.3 ±â€¯7.2% before to 18.6 ±â€¯6.4% after stenting. After stenting, at the proximal normal artery, the total pressures had significantly (P < 0.05) decreased, whereas all the other parameters (WSS, cell Reynolds number, velocity, vorticity, turbulence intensity, turbulence kinetic energy and dissipation rate) had significantly (P < 0.05) increased. At the stenosis, all hemodynamic parameters had significantly decreased. At the stenosis perforating branch, the WSS, cell Reynolds number, velocity, and vorticity were all significantly decreased, and the total pressure, turbulence intensity, kinetic energy, and dissipation rate were all significantly increased. At the distal normal artery, the total flow pressure (perfusion pressure) and velocity were both significantly (P < 0.05) increased, and the total pressure, WSS, cell Reynolds number, vorticity, turbulence intensity, kinetic energy, and dissipation rate were all significantly (P < 0.05) decreased. The hemodynamic parameters after stenting were closer to those after virtual stenosis repair at all measurements. CONCLUSION: Sub-satisfactory recanalization has significantly restored the stenosis and improved the hemodynamic parameters near the stenosis and at the root of the perforating branch, thus significantly improving the cerebral perfusion, similar to the changes of hemodynamic status and cerebral perfusion after virtual removal of the vascular stenosis. This may indicate the good effect of sub-satisfactory stenting recanalization of the vascular stenosis at the posterior circulation.

Safety and efficacy of enterprise stenting for symptomatic atherosclerotic severe posterior circulation stenosis.

PURPOSE: To investigate the safety and efficacy of Enterprise stent angioplasty and risk factors for the prognoses in treating symptomatic severe posterior circulation atherosclerotic stenosis (SSPCAS). MATERIALS AND METHODS: Patients with SSPCAS who were treated with the Enterprise stent angioplasty were retrospectively enrolled. The clinical data, peri-procedural complications, postoperative residual stenosis, in-stent restenosis and recurrent stroke at follow-up were analyzed. RESULTS: 262 patients with 275 stenotic lesions treated with the Enterprise stent angioplasty were enrolled. The stenosis degree was reduced from 86.3 ± 6.2% before to 19.3 ± 5.4% after stenting. Complications occurred in 14 (5.3%) patients. Clinical follow-up was performed in 245 (93.51%) patients for 16.5 ± 7.3 months. During 1 year follow-up, 7 patients (2.9%) had recurrent symptoms, including 4 patients with stenting in the intracranial vertebral artery and 3 in the basilar artery. Imaging follow-up was conducted in 223 (85.11%) patients. In-stent restenosis was present in 35 patients (15.7%), with the restenosis rate of 26.4% (n = 23) in the intracranial vertebral artery, which was significantly (P < 0.001) greater than in the basilar artery (8.8%). Six patients (17.1%) with in-stent restenosis were symptomatic. The stenotic length was the only significant (P = 0.026 and 0.024, respectively) independent risk factor for 1 year stroke or death events and in-stent restenosis. CONCLUSION: The Enterprise stent can be safely and efficaciously applied in the treatment of symptomatic severe posterior circulation atherosclerotic stenosis, with a relatively low rate of in-stent restenosis and recurrent stroke within 1 year. The stenotic length was the only significant independent risk factor for 1 year stroke or death events and in-stent restenosis.

Application of retrievable Solitaire AB stents in the endovascular treatment of acute ischemic stroke.

Purpose: Retrievable stents are widely used in acute ischemic stroke (AIS); however, the results remain unclear in Chinese patients. This study aimed to explore the usefulness of Solitaire AB stents in AIS. Materials and Methods: Seventy-three AIS patients treated with Solitaire AB stents for thrombectomy of large artery occlusion of anterior circulation in January 2014-June 2015 were retrospectively evaluated. Recanalization was assessed with the Thrombolysis In Cerebral Ischemia (TICI) scale. Clinical outcomes were assessed according to the National Institute of Health Stroke Scale (NIHSS) and the modified Rankin Scale (mRS). Operation-related complications were recorded. The main factors affecting successful recanalization with Solitaire AB were analyzed. Results: The 73 patients enrolled included 39 males and 34 females (median age of 59 [31-78] years); 77 Solitaire AB stents were used. The initial recanalization rate with Solitaire AB as the first thrombectomy method was 53.42% (39/73; recanalization group). Among the 34 patients with failed stent retrieval, 32 underwent other treatments; the final arterial recanalization rate was 89.04% (65/73). Perioperative embolization events and symptomatic intracranial hemorrhage (sICH) occurred in 5 and 8 patients, respectively. The mean NIHSS score was 9.12±3.86 one week after thrombectomy, significantly lower compared with admission values. In 31 patients (42.47%), NIHSS score decreased by >8. Good functional independence (mRS score≤2) was achieved in 39 patients (53.42%) at 90 days; 12 patients (16.44%) died. Compared with the recanalization group, the remaining patients showed lower AF and higher LAA percentages. Conclusion: Solitaire AB stents are useful in the endovascular treatment of AIS.

Microwave-assisted synthesis of silver indium tungsten oxide mesocrystals and their selective photocatalytic properties.

A new kind of silver indium tungsten oxide (AgIn(WO(4))(2)) mesocrystals with high hierarchy can be synthesized by a microwave-assisted approach, which shows high and selective photocatalytic activity for the degradation of different organic dyes under UV and visible light irradiation.