Trial of Thrombectomy 6 to 24 Hours after Stroke Due to Basilar-Artery Occlusion.

BACKGROUND: The effects and risks of endovascular thrombectomy 6 to 24 hours after stroke onset due to basilar-artery occlusion have not been extensively studied. METHODS: In a trial conducted over a 5-year period in China, we randomly assigned, in a 1:1 ratio, patients with basilar-artery stroke who presented between 6 to 24 hours after symptom onset to receive either medical therapy plus thrombectomy or medical therapy only (control). The original primary outcome, a score of 0 to 4 on the modified Rankin scale (range, 0 to 6, with a score of 0 indicating no disability, 4 moderately severe disability, and 6 death) at 90 days, was changed to a good functional status (a modified Rankin scale score of 0 to 3, with a score of 3 indicating moderate disability). Primary safety outcomes were symptomatic intracranial hemorrhage at 24 hours and 90-day mortality. RESULTS: A total of 217 patients (110 in the thrombectomy group and 107 in the control group) were included in the analysis; randomization occurred at a median of 663 minutes after symptom onset. Enrollment was halted at a prespecified interim analysis because of the superiority of thrombectomy. Thrombolysis was used in 14% of the patients in the thrombectomy group and in 21% of those in the control group. A modified Rankin scale score of 0 to 3 (primary outcome) occurred in 51 patients (46%) in the thrombectomy group and in 26 (24%) in the control group (adjusted rate ratio, 1.81; 95% confidence interval [CI], 1.26 to 2.60; P<0.001). The results for the original primary outcome of a modified Rankin scale score of 0 to 4 were 55% and 43%, respectively (adjusted rate ratio, 1.21; 95% CI, 0.95 to 1.54). Symptomatic intracranial hemorrhage occurred in 6 of 102 patients (6%) in the thrombectomy group and in 1 of 88 (1%) in the control group (risk ratio, 5.18; 95% CI, 0.64 to 42.18). Mortality at 90 days was 31% in the thrombectomy group and 42% in the control group (adjusted risk ratio, 0.75; 95% CI, 0.54 to 1.04). Procedural complications occurred in 11% of the patients who underwent thrombectomy. CONCLUSIONS: Among patients with stroke due to basilar-artery occlusion who presented 6 to 24 hours after symptom onset, thrombectomy led to a higher percentage with good functional status at 90 days than medical therapy but was associated with procedural complications and more cerebral hemorrhages. (Funded by the Chinese National Ministry of Science and Technology; BAOCHE ClinicalTrials.gov number, NCT02737189.).

Combined Approach to Eptifibatide and Thrombectomy in Acute Ischemic Stroke Because of Large Vessel Occlusion: A Matched-Control Analysis.

BACKGROUND: In patients undergoing mechanical thrombectomy (MT), adjunctive antithrombotic might improve angiographic reperfusion, reduce the risk of distal emboli and reocclusion but possibly expose patients to a higher intracranial hemorrhage risk. This study evaluated the safety and efficacy of combined MT plus eptifibatide for acute ischemic stroke. METHODS: This was a propensity-matched analysis of data from 2 prospective trials in Chinese populations: the ANGEL-ACT trial (Endovascular Treatment Key Technique and Emergency Workflow Improvement of Acute Ischemic Stroke) in 111 hospitals between November 2017 and March 2019, and the EPOCH trial (Eptifibatide in Endovascular Treatment of Acute Ischemic Stroke) in 15 hospitals between April 2019 and March 2020. The primary efficacy outcome was good outcome (modified Rankin Scale score 0-2) at 3 months. Secondary efficacy outcomes included the distribution of 3-month modified Rankin Scale scores and poor outcome (modified Rankin Scale score 5-6) and successful recanalization. The safety outcomes included any intracranial hemorrhage, symptomatic intracranial hemorrhage, and 3-month mortality. Mixed-effects logistic regression models were used to account for within-hospital clustering in adjusted analyses. RESULTS: Eighty-one combination arm EPOCH subjects were matched with 81 ANGEL-ACT noneptifibatide patients. Compared with the no eptifibatide group, the eptifibatide group had significantly higher rates of successful recanalization (91.3% versus 81.5%; P=0.043) and 3-month good outcomes (53.1% versus 33.3%; P=0.016). No significant difference was found in the remaining outcome measures between the 2 groups. All outcome measures of propensity score matching were consistent with mixed-effects logistic regression models in the total population. CONCLUSIONS: This matched-control study demonstrated that MT combined with eptifibatide did not raise major safety concerns and showed a trend of better efficacy outcomes compared with MT alone. Overall, eptifibatide shows potential as a periprocedural adjunctive antithrombotic therapy when combined with MT. Further randomized controlled trials of MT plus eptifibatide should be prioritized. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03844594 (EPOCH), NCT03370939 (ANGEL-ACT).

Application of Mobile Stroke Unit in Prehospital Thrombolysis of Acute Stroke: Experience from China.

BACKGROUND AND PURPOSE: Most patients cannot receive intravenous thrombolytic therapy in the early stage of stroke onset, and the application of mobile stroke unit (MSU) in prehospital intravenous thrombolytic therapy of acute stroke may change this situation. The first MSU in China was put into use in 2017. Herein, we aimed to explore the preliminary experience of MSU in prehospital thrombolysis of acute stroke. METHODS: Patients who received prehospital intravenous thrombolytic therapy using MSU were classified to the MSU thrombolysis group, and the control group consisted of stroke patients admitted by regular ambulances, who were transferred to hospital for intravenous thrombolytic therapy. The feasibility, safety, and duration of procedures were compared. RESULTS: There were 14 patients received prehospital intravenous thrombolysis on the MSU, and 24 patients underwent intravenous thrombolysis in the emergency center, who were transferred by the ordinary ambulance during the same period. The median call-to-needle time was 59.5 min in the MSU thrombolysis group, while it was 89 min in the control group; the difference between the 2 groups was statistically significant (p = 0.001). The median time from onset to thrombolysis was 70 and 102.5 min, respectively, in the 2 groups (p = 0.002). The percentages of good clinical outcome (modified Rankin Scale score ≤ 2) at 90-day follow-up were 79 and 67%, respectively (p = 0.488). The rate of symptomatic intracranial hemorrhage and mortality during the perioperative period did not differ significantly between 2 groups. CONCLUSION: Despite the small sample size, our preliminary experience of the application of MSU in the prehospital thrombosis therapy seems to indicate a significant reduction in time from call to needle, the efficacy of MSU in the treatment of acute stroke needs further experiment and larger sample size to confirm.

Astrocyte-derived exosomes suppress autophagy and ameliorate neuronal damage in experimental ischemic stroke.

The aim of this study was to investigate the role of astrocyte-derived exosomes (AS-Exo) on neuronal damage in ischemic stroke. We isolated astrocytes from 3- to 4-day-old C57BL/6 mice and astrocytes were identified by GFAP immunostaining. Exosomes were obtained from astrocyte supernatant by overspeed centrifugation. For investigating the effect of AS-Exo on the apoptosis of neurons after oxygen and glucose deprivation (OGD), the exosome labeling and uptake by neurons were observed by confocal laser microscopy, then HT-22 cell vitality and apoptosis were determined by Cell Counting Kit-8 (CCK-8) assay and Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, respectively. Tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1ß (IL-1ß) in OGD-induced HT-22 was analyzed by Enzyme-linked immunosorbent assay (ELISA). Apoptosis-related protein in HT-22 was analyzed by Western blot. For investigating the effect of AS-Exo on the OGD neurons autophagy, expression of Beclin-1, LC3-I, LC3-II and P62 in OGD-induced HT-22 was analyzed by Western blot. For animal experiments, C57BL/6 mice (6-8 weeks old) models of middle cerebral artery occlusion were used to create permanent focal ischemia. AS-Exo were injected intravenously through the tail vein into ischemic mice at a concentration of 80 µg per 2 ml after 60 min of the ligation operation The results showed that AS-Exo enhanced neurons viability; inhibited OGD-induced apoptosis, inhibited OGD-induced expressions of caspase-3 and Bax and levels of TNF-α, IL-6 and IL-1ß in HT-22 cells. Further findings showed AS-Exo inhibited OGD-induced neurons apoptosis via regulating autophagy. AS-Exo ameliorated neuronal damage through regulating autophagy in vivo. Our data indicate that AS-Exo suppress autophagy and ameliorate neuronal damage in experimental ischemic stroke.

Overexpressed circ_0029426 in glioblastoma forecasts unfavorable prognosis and promotes cell progression by sponging miR-197.

Accumulating studies indicates that circular RNAs (circRNAs) play an imperative role in modulating cancer progression and metastasis. In the previous study, elevated circ_0029426 was first observed in glioblastoma (GBM) tissues compared with normal tissues by circRNA microarray. Our aim is to study the function and mechanism of circ_0029426 in GBM. Quantitative reverse transcription polymerase chain reaction was used to detect relative circ_0029426 expression in GBM tissue samples and cells. Fisher's exact test was used to evaluate the expression of circ_0029426 and clinical parameters.The Kaplan-Meier method and Cox regression were analyzed to evaluate the link between circ_0029426 expression and the overall survival of patients with GBM. Loss/gain-of function experiments were performed to measure GBM cell growth, apoptosis, migration, and invasion. Dual luciferase reporter assays were applied to detect the binding ability between circ_0029426 and miR-197. As a result, the circ_0029426 expression is tightly correlated with patients' clinical severity and prognosis. Functionally, circ_0029426 strikingly promoted cell proliferation, migration and invasion, and inhibited cell apoptosis. Mechanistically, miR-197 was predicted and verified to be sponged by circ_0029426. More importantly, the oncogenic functions of circ_0029426 are partially attributed to its suppression on miR-197. Collectively, circ_0029426 may be taken as a potential therapeutic target for GBM.

Extending the Propagation Distance of a Silver Nanowire Plasmonic Waveguide with a Dielectric Multilayer Substrate.

Chemical-synthesized silver nanowires have been proven as an efficient architecture for plasmonic waveguides, but the high propagation loss prevents their widely applications. Here, we demonstrate that the propagation distance of the plasmons along a silver nanowire can be extended if this nanowire was placed on a dielectric multilayer substrate containing a photonic band gap but not placed on a commonly used glass substrate. The propagation distance at 630 nm wavelength can reach 16 µm, even when the silver nanowire is as thin as 90 nm in diameter. Experimental and simulation results further show that the polarization of this propagating plasmon mode was nearly parallel to the surface of the dielectric multilayer, so it can be excited by a transverse-electric polarized Bloch surface wave propagating along a polymer nanowire with diameter at only about 170 nm on the same dielectric multilayer. Numerical simulations were also carried out and are consistent with the experiment results. Our work provides a platform with which to extend the propagation distance of the plasmonic waveguide and also for the integration between photonic and plasmonic waveguides on the nanometer scale.

Near-Infrared Circularly Polarized Light Triggered Enantioselective Photopolymerization by Using Upconversion Nanophosphors.

Circularly polarized light (CPL) is considered to be a true chiral entity and has been suggested as an explanation for the introduction of initial chiral biases into key biomolecular building blocks. CPL used recently asymmetric photochemical reactions is of wavelengths mainly in the UV and visible regions, whereas natural CPL observed in star-forming regions of the Orion constellation falls in the IR region. Whether CPL in the IR or near-IR region could be utilized to trigger asymmetric photochemical reactions remains to be determined. Herein, it is demonstrated that enantioselective photopolymerization can be realized by using λ=980 nm CPL as the only chiral source. By incorporating NaYF4 nanophosphors as the antenna species, the enantioselective photopolymerization of achiral benzaldehyde-substituted diacetylene monomer can be realized based on an upconversion mechanism upon exposure to λ=980 nm CPL. The screw direction of the helical PDA chains can be completely controlled by the handedness of incident λ=980 nm CPL.

Radiative decay engineering 8: Coupled emission microscopy for lens-free high-throughput fluorescence detection.

Fluorescence spectroscopy and imaging are now used throughout the biosciences. Fluorescence microscopes, spectrofluorometers, microwell plate readers and microarray imagers all use multiple optical components to collect, redirect and focus the emission onto single point or array imaging detectors. For almost all biological samples, except those with regular nanoscale features, emission occurs in all directions. With the exception of complex microscope objectives with large collection angles (NA ≤ 0.5), all these instruments collect only a small fraction of the total emission. Because of the increasing knowledge base on fluorophores within near-field (<200 nm) distances from plasmonic and photonic structures we can anticipate the development of compact devices in which the sample to be detected is located directly on solid state detectors such as CCDs or CMOS cameras. Near-field interactions of fluorophores with metallic or dielectric multi-layer structures (MLSs) can capture a large fraction of the total emission. Depending on the composition and dimensions of the MLSs, the spatial distribution of the sample emission results in distinct optical patterns on the detector surface. With either plain glass slides or MLSs the most commonly used front focal plane (FFP) images reveal the x-y spatial distribution of emission from the sample. Another approach, which is often used with two or three-dimensional nanostructures, is back focal plane (BFP) imaging. The BFP images reveal the angular distribution of the emission. The FFP and BFP images occur at certain distances from the sample which is determined by the details of the optical components. Obtaining these images requires multiple optical components and distances which are too large for the compact devices. For devices described in this paper, the images will be detected at a fixed distance between the sample and some arbitrary distance below the MLS which is determined by the geometry and thicknesses of the components. We refer to measurements at these locations as out-of-focal plane (OFP) imaging. Herein we describe a method to measure the optical fields at micron and multi-micron distances below the MLS, which will represent the images seen by an optically coupled array detector. The possibility of sub-surface optical images is illustrated using five different multi-layer structures. This is accomplished using an optical configuration which allows measurement at a front focal plane (FFP), back focal plane (BFP) or any OFP locations. Our OFP imaging method provides a link between the FFP images which reveals the surface distribution of fluorophores with the BFP images that reveal the angular distribution of emission. This linkage can be useful when examining structures which have nanoscale features due to fluorescence or leakage radiation from nanostructures.

Outcomes of middle cerebral artery angioplasty and stenting with Wingspan at a high-volume center.

INTRODUCTION: This study was to investigate the periprocedural stroke rates, safety, and long-term effect of Wingspan stenting for symptomatic severe stenosis of the middle cerebral artery (MCA) at a high-volume center. METHODS: Between July 2007 and April 2013, 196 consecutive patients with severe MCA atherosclerotic stenosis (≥70%) who were treated with Wingspan stenting were retrospectively studied. All patients had arterial stenosis-related temporary ischemic attack or strokes. The demographic data, cerebral angiography, technical success rate, periprocedural complications, and clinical and imaging follow-up were analyzed. RESULTS: The successful stenting rate was 98.0%, and the stenosis rate was improved from pre-stenting (80.6 ± 8.3 %) to post-stenting (15.5 ± 6.8%). The 30-day periprocedural stroke or death rate was 7.1%, with a disabling or fatal rate of 2.6%. The perioprocedural stroke rate was significantly (P < 0.01) greater in the early learning stage (16.0%) than in the later technical maturation stage (4.1%). The total periprocedural ischemic and perforator stroke rates were greater in patients with the most stenosis in the distal MCA 1/3 segment (6.8 and 5.7%, respectively) than in the proximal and middle 2/3 segments (0.9 and 0%, respectively). The ipsilateral stroke or death rate beyond 30 days (6-69 months, mean 30 ± 16) was 4.8%, with the 1- and 2-year cumulative stroke rates of 9.6 and 12.1%, respectively. Imaging follow-up 6-69 months (mean 10.9 ± 8.5) revealed restenosis in 21 cases (20.4 %). CONCLUSION: Intracranial stenting of MCA stenoses may have the potential of better clinical outcomes if patients are properly selected and treated by an experienced operator at a high-volume center.

Management of tandem internal carotid and middle cerebral arterial occlusions with endovascular multimodal reperfusion therapy.

The aim of this study was to evaluate the safety and efficacy of multimodal reperfusion therapy (MMRT) for tandem internal carotid artery and middle cerebral arterial (TIM) occlusions. Cases of TIM occlusion were collected and retrospectively reviewed. The analyzed objects included etiology, sites of tandem occlusion, collateral flow, location and size of infarcts. Combined with mechanical recanalization techniques and its complications, the National Institute of Health Stroke Scale (NIHSS) score and imaging data that was derived pre- and post-procedure were further contrasted. The study enrolled six patients with TIM occlusions. The mean NIHSS score on admission was 17 (range 13-20) and the median time from puncture to recanalization was 141 min (range 60-230). The substantial recanalization rate (Thrombolysis in Cerebral Infarction 2b or 3) was 83.3% and no symptomatic intracerebral hemorrhage was observed. The mean NIHSS score after three days was 14 (range 10-19) and 9 (range 3-17) following discharge. However, one patient died of pulmonary infection one month after discharge. For the five patients who survived, the modified Rankin Scale was evaluated at three months, with scores of 3, 1, 3, 5 and 3, respectively. It is concluded that endovascular therapy for acute TIM occlusions are complex, MMRT may be relatively safe and effective.

Fluorescence emission difference with defocused surface plasmon-coupled emission microscopy.

A novel fluorescence emission difference method is proposed to improve the lateral resolution of SPCEM without increasing instrument complexity. We discovered the profile of transverse PSF in SPCEM will dramatically change from a hollow spot to a solid spot, when the axial position of sample varies within one wavelength in the vicinity of the focal plane. The subtraction of an image whose PSF is hollow spot and an image with solid PSF will greatly enhance the resolution and contrast of SPCEM images. The mechanism of the distinctive PSF is demonstrated through basic optics theories, and the improvement of lateral resolution is verified by theoretical simulations and experimental results. It is believed that our method will stand out for its pleasant resolution enhancement and its instruments' simplicity to facilitate many biological cellular observations.

Extracting surface wave-coupled emission with subsurface dielectric gratings.

Conventional surface plasmons (SPs) or Bloch surface waves (BSWs) have a wave vector exceeding that of light in vacuum, and, therefore, the surface plasmon-coupled emission (SPCE) or Bloch surface wave-coupled emission (BSWCE) cannot escape from the corresponding structures. With the aid of a high-refractive-index prism or an oil-immersion objective, the SPCE or BSWCE can be coupled into free space. But the large volumes of the prism and objective are certainly unfavorable for miniaturization of the optical systems or inconvenient for applications such as the optical displays. Here we experimentally demonstrate a new method to extract the SPCE or BSWCE with a subsurface dielectric grating. The experimental results verify that the chip-like substrate with two decorated sides can bring out the directional fluorescence emission in free space. The emitting direction and emitting patterns can be tuned by the period size and dimensionality of the gratings. Our work provides a new strategy to realize free-space directional fluorescence emission at a very low cost and compact configuration, which has potential applications in fluorescence-based sensing, imaging, light-emitting diodes, optical displays, and other near-field optical devices.

Effect of metal film thickness on Tamm plasmon-coupled emission.

Tamm plasmons (TPs) are the result of trapping optical energy at the interface between a metal film and a one-dimensional photonic crystal. In contrast to surface plasmons, TPs display unique properties such as the ability to undergo direct optical excitation without the aid of prisms or gratings, being populated using both S- and P-polarized light, and importantly, they can be created with incident light normal to the surface. This latter property has recently been used to obtain Tamm plasmon-coupled emission (TPCE), which beams along a path directly perpendicular to the surface. In this paper the effects of metal film thickness on the TPCE are investigated using back focal plane (BFP) imaging and spectral resolutions. The observed experimental results are in agreement with the numerical simulations. The present work provides the basic understanding needed to design structures for TPCE, which in turn has potential applications in the fabrication of active materials for light emitting devices, fluorescence-based sensing, using microarrays, and imaging.

Perioperative complications of recanalization and stenting for symptomatic nonacute vertebrobasilar artery occlusion.

BACKGROUND: Endovascular recanalization and stenting has been used to treat patients with symptomatic nonacute intracranial vertebrobasilar artery occlusion (VBAO) refractory to aggressive medical treatment. This study was performed to analyze the perioperative complications of the procedures. METHODS: Between February 2010 and March 2012, 27 consecutive patients (24 men, 3 women; age: 57 ± 10 years) with symptomatic, nonacute intracranial VBAO including 12 basilar artery occlusions and 15 vertebral artery occlusions were collected and retrospectively analyzed. RESULTS: The median time between symptom onset and recanalization was 1.5 months (interquartile range [IQR]: 0.7-3.4) and between imaging-documented occlusion and recanalization was 9.5 days (IQR: 6-18 days). Recanalization was achieved in 96% of patients (26/27). Five (5/27; 19%) perioperative complications occurred. Two patients had dissections: 1 dissection resulted in termination of the procedure without successful recanalization, and the other was handled by the placement of 2 stents. There was 1 intraprocedural acute thrombosis that was successfully treated with balloon angioplasty. One patient experienced thrombus disruption and translocation during the procedure: thrombus was dislodged after disruption by the guidewire. There was 1 acute reocclusion after procedure: while recanalization was achieved again, there was no improvement in clinical outcome. CONCLUSIONS: This study revealed that recanalization and stenting for nonacute VBAO may be technically feasible but that it is accompanied by a high risk of complication. The causative factors for perioperative complications need future study.

Dynamically generating a large-area confined optical field with subwavelength feature size.

By using a prism of high refractive index, free-space cylindrical vector beams can be selectively converted into confined optical fields with large area, such as surface plasmon polaritons or waveguide modes, whose interference will produce optical features at the nanometer scale. Due to the polarization sensitivity of these modes, the macroscopic distribution of the confined field can be dynamically manipulated through an electronically driven liquid crystal. Based on these phenomena, a promising maskless interference nanolithography is proposed and experimentally demonstrated.

Dark-field imaging by active polymer slab waveguide.

A dark-field imaging technique taking advantage of the active polymer slab waveguide (APSW) is experimentally investigated. The dye molecules (Rhodamine 6G, Rh6G) are doped in the polymer film for the launching of surface waves on the APSW, such as the surface plasmon polaritons on the Ag-polymer-air interface, evanescent fields at the polymer-air interface by the total internal reflection, or the guided modes. The localized surface waves will not radiate into the far-field space directly. When the specimens are placed on the surface of the APSW, these surface waves will be scattered to the far-field region, which forms the dark-field image of the specimen. Experimental results show that usage of APSW leads to high-contrast dark-field images with the conventional optical microscope system. The polymer film involved in the proposed dark-field microscopy brings about the merits of reduced roughness, good stability, bio-compatibility, and shorter wavelength of the illumination light source.

Comparison of drug-coated balloon with conventional balloon for angioplasty in symptomatic intracranial atherosclerotic stenosis.

BACKGROUND: Drug-coated balloon (DCB) angioplasty has been studied for reducing the occurrence of restenosis after treatment for intracranial atherosclerotic stenosis (ICAS), but no comparison has been published of the use of drug-coated and non-coated balloons in angioplasty for ICAS. We aim to compare the safety and efficacy of DCB angioplasty with conventional balloon (CB) angioplasty for the treatment of symptomatic ICAS. METHODS: One hundred cases with symptomatic ICAS treated with DCB (n=49) and CB (n=51) angioplasty were retrospectively analyzed. 1:1 propensity score matching (PSM) was completed to eliminate bias in the patients selected for further analysis. The periprocedural events and follow-up outcomes between the two groups were compared. RESULTS: There were 32 cases in each group after PSM. Technical success (<50% residual stenosis) was achieved in 30 cases (93.8%) in the DCB group and in 28 cases (87.5%) in the CB group. The rates of stroke or mortality within 30 days were 3.1% in the DCB group and 6.3% in the CB group (p=1). The incidence of restenosis in the DCB group (6.3%) was significantly lower than that in the CB group (31.3%) (p=0.01). CONCLUSIONS: Compared with CB angioplasty, DCB angioplasty can effectively reduce the incidence of restenosis. Further studies are needed to validate the role of DCB angioplasty in the management of symptomatic ICAS.

Endovascular recanalization of symptomatic non-acute occlusion of the vertebrobasilar artery.

Purpose: The study aimed to investigate the safety, effect, and risk factors of endovascular recanalization of symptomatic non-acute occlusion of the vertebrobasilar artery (SNOVA). Materials and methods: Patients with SNOVA were retrospectively enrolled and treated with endovascular recanalization. The clinical data, endovascular treatment, peri-procedural complications, and follow-up outcomes were analyzed. Results: A total of 88 patients were enrolled, with an interval to recanalization of 2-89 days (median 23) and an mRS of 2-5 (median 3 and IQR 1). Occlusion was in the intracranial vertebral artery in 68 (77.27%) patients and basilar artery in 20 (22.73%), with an occlusion length of 4.5-43.7 mm (mean 18.3 ± 8.8). Endovascular recanalization was successful in 81 (92.0%) patients. Post-dilatation was performed in 23 (28.4%) patients. After stenting, the residual stenosis was 10%-40% (mean 20.2% ± 7.6%). Peri-procedural complications occurred in 17 (19.3%) patients, with a mortality rate of 5.7%. In total, 79 (95.18%) patients underwent follow-up 5-29 (mean 16.9 ± 5.5) months later, with an mRS score of 0-6 (median 1 and IQR 1) at follow-up, being significantly (p < 0.0001) better than that at discharge. Stroke occurred in 9 patients (11.4%) in 1 year. In-stent restenosis occurred in 19 (25.33%) patients. Significant (p < 0.05) independent risk factors were blunt occlusion for successful recanalization, duration to recanalization and blunt occlusion for peri-procedural complications, and post-dilatation for both in-stent restenosis and 1-year stroke or death events. Conclusion: Endovascular recanalization of symptomatic non-acute occlusion of the vertebrobasilar artery is feasible even for a long occlusion segment, with a high recanalization rate, a low complication rate, and a good prognosis. Blunt occlusion and duration from the onset to recanalization may affect successful recanalization and peri-procedural complications while post-dilatation may affect in-stent restenosis and prognosis.

MRI arterial spin labeling in evaluating hemorrhagic transformation following endovascular recanalization of subacute ischemic stroke.

Objective: To investigate the value of the MRI arterial spin labeling (ASL) in evaluating the blood-brain barrier permeability of anterior circulation ischemic lesions in subacute ischemic stroke (SIS) and the risk of hemorrhage transformation (HT) after endovascular recanalization. Materials and methods: Patients with anterior circulation SIS treated with endovascular recanalization were prospectively enrolled. The imaging presentations in the MRI ASL sequences, dynamic contrast-enhanced (DCE) sequence, and Xper CT were studied. The relative cerebral blood flow (rCBF), volume transfer constant (Ktrans), and the weighted Kappa coefficient (rKtrans) were analyzed. Results: Among 27 eligible patients, HT occurred in 7 patients (25.92%). Patients with HT had significantly higher rCBF value (1.56 ± 0.16 vs. 1.16 ± 0.16), Ktrans, (0.08 ± 0.03 min vs. 0.03 ± 0.01 min) and rKtrans (3.02 ± 0.89 vs. 1.89 ± 0.56). The ASL imaging sequence had a high consistency with the DCE sequence and Xper CT with a high weighted Kappa coefficient of 0.91 for the DCE sequence and 0.70 for the Xper CT imaging. The DCE sequence was also highly consistent with the Xper CT in imaging classification with a high weighted Kappa coefficient of 0.78. The rCBF value in the 21 patients with the subcortical and basal ganglia infarction was significantly lower than that in the other 6 patients with the cortical infarction (1.222 ± 0.221 vs. 1.413 ± 0.259, t = 1.795, P = 0.004). Conclusion: The MRI ASL sequence has an important role in evaluating the blood-brain barrier permeability and the risk of hemorrhagic transformation of anterior circulation SIS following endovascular recanalization.

Safety and Efficacy of Direct Thrombectomy Versus Bridging Therapy in Patients with Acute Ischemic Stroke Eligible for Intravenous Thrombolysis: A Meta-Analysis of Randomized Controlled Trials.

OBJECTIVE: In the present study, we conducted a meta-analysis of reported randomized controlled trials (RCTs) comparing the safety and efficacy of direct thrombectomy (DT) and bridging therapy (BT) for patients eligible for intravenous thrombolysis (IVT). METHODS: A comprehensive search of PubMed, Cochrane Library, EMBASE, and Web of Science up to July 11, 2022 was performed. RCTs comparing DT and BT were included. The relative risk or rate difference and their 95% confidence intervals in a Mantel-Haenszel fixed effects model were used as the effect index of each outcome. The noninferior margin was specified as 80% for the relative risk or -10% for the rate difference. The primary outcome was the proportion of patients with a favorable functional outcome, defined as a modified Rankin scale (mRS) score of 0-2 or a return to baseline at 90 days. Additional efficacy and safety outcomes included successful recanalization at the end of thrombectomy, excellent clinical outcomes (defined as an mRS score of 0-1), death within 90 ± 14 days, symptomatic intracerebral hemorrhage, any type of intracerebral hemorrhage, and clot migration. RESULTS: Six RCTs with 2334 patients were pooled for the meta-analysis. The results showed the noninferiority of DT for favorable functional outcomes, higher successful recanalization rates, and any intracerebral hemorrhage in the BT group, with no statistically significant differences for other outcomes. The risk of bias for all RCTs in our analysis was low. CONCLUSIONS: DT achieved noninferiority to BT for favorable functional outcomes. Patient-level pooled analysis and subgroup analysis are needed to provide more information to distinguish which patients will benefit more from which therapy.