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Purpose Clinical approach for staging cerebral venous sinus thrombosis (CVST) depends on the duration from symptom onset to clinical diagnosis, which is subjective and may be incorrect. To investigate if T1-weighted signal characteristics of the thrombus can be used for staging the thrombus on segment level and predicting endovascular therapy outcome. Methods Ninety-one CVST patients underwent non-contrast-enhanced T1-weighted 3D variable-flip-angle fast-spin-echo (T1-SPACE) and 29 of them received endovascular therapy. We divided the 91 patients into acute, subacute, and chronic CVST stage according to the clinical approach, and then analyzed the T1 weighted signal characteristics (i.e., thrombus shape and signal intensity) of the thrombus at each stage. To investigate the endovascular therapy outcome associated with the thrombus stage and signal characteristics, we evaluated the thrombolytic ratio on patient level and recanalization rate on segment level, respectively. Results The thrombi at acute or chronic stage were depicted as isointense signals but as hyperintense signals at subacute stage. Compared to the thrombus at acute stage, the thrombus at chronic stage was contractive and can be distinguished. Developing thrombi at transition periods of acute-to-subacute or subacute-to-chronic stage were found appearing mixed iso-/hyper-intense signals. On patient’s level, the patients at earlier stage had higher thrombolytic ratio (acute: 80.7 ± 18.3%, subacute: 62.6 ± 36.3%, chronic: 22.9 ± 24.2%). On segment level, the thromboembolic segments of isointense or mixed iso-/hyper-intense thrombi at non-chronic stage had good thrombolytic outcome. Conclusion T1-weighted signal characteristics of the thrombus can be used for staging CVST and predicting the endovascular therapy outcome.

Iatrogenic ICA injury is a life‐threatening and underreported complication of EES. For selected patients, covered stent implantation is the best and only way to block the rupture spot immediately and maintain ICA blood flow., Endovascular procedure in the treatment of iatrogenic ICA rupture in EES. ​

This study aimed to evaluate prognostic parameters associated with favorable clinical prognosis and assess the feasibility and safety of three different treatment strategies in patients with acute intracranial vertebrobasilar artery occlusion (VBAO). A total of 159 patients with acute VBAO at 3 stroke centers between September 2015 and October 2018 were retrospectively analyzed. Eighty-nine patients underwent mechanical thrombectomy (MT) alone, 43 underwent MT with additional rescue angioplasty, and 27 underwent primary balloon angioplasty (without or with stenting). In patients treated with primary or rescue balloon angioplasty (without or with stenting), a low-dose intra-arterial tirofiban injection was used. The reperfusion status was assessed after the procedure, and the functional outcome was assessed at 90-day follow-up. The baseline characteristics and 90-day prognosis of three different treatment subgroups were comparatively analyzed. Overall, successful reperfusion and a favorable outcome were achieved in 96.86% (154/159) and 46.54% (74/159) patients, respectively. The onset to puncture time (461.96 min vs 603.59 min, P = 0.000), procedure time (64.12 min vs 70.47 min, P = 0.007), and onset to reperfusion time (526.08 min vs 674.47 min, P = 0.000) were significantly shorter in patients with favorable outcomes than in those with poor outcomes. Among different endovascular treatment subgroups, no significant differences were found in successful reperfusion and 90-day outcome. Low-dose tirofiban did not increase the risk of symptomatic intracranial hemorrhage and the 90-day mortality in patients with acute VBAO. Individualized endovascular treatment strategy for selected patients with acute VBAO could achieve satisfactory reperfusion rate and favorable prognosis.

Background Vessel perforation is a serious technical complication during mechanical thrombectomy (MT) for the treatment of acute ischemic stroke with large vessel occlusion. Routine rescue strategy includes balloon occlusion for tamponade, procedure suspension, and lowering or normalizing blood pressure. However, this complication is still associated with poor outcome and high mortality. Methods In this paper, the authors report their experience by using glue to embolize the ruptured vessel secondary to microcatheter/microwire perforation, preventing further deterioration in clinical outcome. Rescue glue embolization was attempted in 2 patients who developed intraprocedural vessel perforation while trying to gain access through the blocked artery with a microcatheter/microwire. Results The ruptured vessels were effectively occluded. Stent retriever thrombectomies were then continued, and TICI 2b and 3 recanalizations were achieved. Both patients' neurologic status improved. Conclusions The key benefit of this method exists in embolizing the ruptured vessel without affecting the following MT. We propose the rescue glue embolization is simple yet effective in managing vessel perforation complication during MT.

Objective: Symptomatic in-stent restenosis (sISR) is the major cause of medium- or long-term cerebral infarctions in patients who underwent percutaneous transluminal angioplasty and stenting for severe intracranial atherosclerotic stenosis. This study aims to evaluate the feasibility and safety of paclitaxel-coated balloon (PCB) angioplasty for the treatment of intracranial sISR. Methods: We report 11 cases of PCB angioplasty for intracranial sISR. Lesion locations and number were as follows: intracranial internal carotid artery (n = 4), M1 segment of middle cerebral artery (MCA) (n = 1), V4 segment of vertebral artery (n = 6). The technical success rate, periprocedural complications, and short-term outcome were retrospectively analyzed. Results: All procedures were successfully performed without periprocedural complication. Asymptomatic vessel dissection after PCB inflation occurred in one case. Postprocedural diffusion-weighted imaging (DWI) showed new asymptomatic ipsilateral infarction in one case. All 11 cases did not experience ipsilateral stroke or death within 30 days or ischemic stroke in the territory of the target artery between 31 and 90 days after procedure. Conclusion: This preliminary study indicates that PCB angioplasty is feasible and safe for the treatment of intracranial sISR. Further studies are needed to clarify its efficiency and long-term outcome.

BackgroundMechanical thrombectomy with a stent retriever (SR) and/or aspiration is the 'gold standard' for the treatment of acute ischemic stroke due to large vessel occlusion (LVO). However, sometimes clots may not be retrievable with a single SR alone or combined with aspiration.ObjectiveTo assess the safety and efficacy of a novel tandem stents thrombectomy (TST) technique as a rescue treatment for acute LVO that is refractory to conventional attempts.MethodsAll patients treated with the TST technique as rescue treatment after failure of conventional attempts were retrospectively reviewed. The postprocedural angiographic and clinical outcome, including modified Thrombolysis in Cerebral infarction (mTICI) grade, National Institutes of Health Stroke Scale (NIHSS) score, and modified Rankin Scale (mRS) score, was assessed.ResultsNine patients (mean age, 65.2 years; median NIHSS score 18) with middle cerebral artery M1 segment (n=6) and terminal internal carotid artery (n=3) occlusions were included in the study. The TST technique was performed as a rescue treatment after unsuccessful stent thrombectomy alone (four cases) and stent thrombectomy plus aspiration (five cases). Successful recanalization (mTICI 2b/3) was achieved in all patients. No procedure-related complications occurred except reversible vasospasms were observed in three patients and one patient developed hemorrhage transformation after the procedure, but was asymptomatic. Three patients had good clinical outcome (mRS score 0–2 at 90 days). Two patients (22.2%) died.ConclusionsThe TST technique seems to be a safe and effective rescue treatment for acute LVO that is refractory to conventional attempts.

Background and Purpose— Symptomatic intracranial hemorrhage (SICH) pose a major safety concern for endovascular treatment of acute ischemic stroke. This study aimed to evaluate the risk and related factors of SICH after endovascular treatment in a real-world practice. Methods— Patients with stroke treated with stent-like retrievers for recanalizing a blocked artery in anterior circulation were enrolled from 21 stroke centers in China. Intracranial hemorrhage was classified as symptomatic and asymptomatic ones according to Heidelberg Bleeding Classification. Logistic regression was used to identify predictors for SICH. Results— Of the 632 enrolled patients, 101 (16.0%) were diagnosed with SICH within 72 hours after endovascular treatment. Ninety-day mortality was higher in patients with SICH than in patients without SICH (65.3% versus 18.8%; P 0.83 (odds ratio [OR], 2.07; 95% confidence interval [CI], 1.24–3.46), pretreatment Alberta Stroke Program Early Computed Tomography Score of 270 minutes (OR, 1.70; 95% CI, 1.03–2.80), >3 passes with retriever (OR, 2.55; 95% CI, 1.40–4.65) were associated with SICH after endovascular treatment. Conclusions— Incidence of SICH after thrombectomy is higher in Asian patients with acute ischemic stroke. Cardioembolic stroke, poor collateral circulation, delayed endovascular treatment, multiple passes with stent retriever device, lower pretreatment Alberta Stroke Program Early Computed Tomography Score, higher baseline neutrophil ratio may increase the risk of SICH.

Objective: To test whether Neuroform EZ stent placement combined with the modified techniques in symptomatic severe intracranial stenosis (ICAS) would result in lower rates of peri-procedural complications of intracranial stenting. Methods: We retrospectively reviewed the clinical data from 71 consecutive patients who underwent Neuroform EZ stent placement combined with the modified techniques for symptomatic severe ICAS at our institute between January 2016 and October 2017. The primary outcomes were ipsi-lateral ischemic stroke, intra-cerebral hemorrhage, or death within 30 days after stenting. The secondary outcome was technical success. Results: The technical success rate was 100%. The mean pre and post-stent stenoses were 84.2% ± 9.1% (median 85%, IQR75% to 90%) and 16.9% ± 10.2 % (median 15%, IQR 10% to 25%). The frequency of ipsi-lateral stroke, intra-cerebral hemorrhage, or death within 30 days was 0%. Conclusions: The combined use of Neuroform EZ stent placement and the modified techniques for symptomatic severe ICAS is technically feasible and safe, with very low peri-procedural complications. Further studies are required to assess the long-term results of this approach.

Purpose Transverse sinus stenosis (TSS) is the most sensitive imaging characteristic of idiopathic intracranial hypertension (IIH). This study aimed to assess the diagnostic performance of contrast-enhanced magnetic resonance high-resolution variable flip angle turbo-spin-echo (T1 SPACE) technique in TSS patients and evaluate the diagnostic accuracy of enhanced T1 SPACE, and phase-contrast magnetic resonance venography (PC MRV) with digital subtraction angiography (DSA) as standard imaging. Method This prospective study enrolled 62 patients with suspected IIH and PC MRV-confirmed transverse sinus stenosis. All patients underwent lumbar puncture, PC MRV, enhanced T1 SPACE sequences and DSA examination. The accuracy, sensitivity, and specificity of enhanced T1 SPACE in detecting venous sinus stenosis were calculated and compared with those of PC MRV. Intermodality agreement (Kendall’s rank correlation coefficients and weighted kappa statistic) was assessed. Results Sixty-two patients were enrolled from November 2016 to October 2018. For the measured stenosis, better correlation was observed in enhanced T1 SPACE and DSA (AUC = 0.953) than PC MRV (AUC = 0.871). Intermodality agreement of enhanced T1 SPACE (rk = 0.895 and weighted ĸ = 0.868) was better than PC MRV (rk = 0.753 and weighted ĸ = 0.653) compared with DSA. Thirty-seven intrasinus filling defects were detected by contrast-enhanced T1 SPACE, while only twenty of them were detected on source imaging of PC MRV. Conclusions The contrast-enhanced T1 SPACE sequence was more sensitive and specific compared with PC MRV in assessing stenosis and detecting lesions in TSS patients. Accurate determination of the presence and extent of TSS using this technique might be useful in patient selection and guiding the treatment.

Insufficient nidus occlusion is a matter of great concern to routine Onyx embolization of brain arteriovenous malformations (AVMs). This paper described an efficient method which using the diluted Onyx embolization technique to treat brain AVM. The diluted Onyx technique was performed in a series of 15 patients with brain AVMs (10 males, 5 females; age range, 11–44 years). It consists of initial embolization with routine Onyx-18, followed by the diluted Onyx (1.5 mL of Onyx-18 diluted with 0.5 mL of DMSO) through the same microcatheter. The technical skills and angiographic and clinical outcomes were analyzed. A total of 15 embolization sessions were performed with diluted Onyx via 16 arterial feeders in these 15 patients. Each patient underwent one attempt of diluted Onyx through a single feeder except one patient. In this patient, the AVM was simultaneously embolized with diluted Onyx through double microcatheters which were placed in two feeders. When the length of reflux reached to 2 cm (or close to the determined length) and the embolic material could not move distally any more despite some rounds of “injection-reflux-waiting,” regular Onyx 18 was changed to diluted Onyx. Antegrade flow of embolic material into the nidus was observed in 12 cases but failed in 3. An average of 90% (range 55–100%) estimated size reduction was achieved, and 6 AVMs were completely obliterated. No functionally relevant complications occurred. The diluted Onyx technique could be a useful adjunct to routine Onyx embolization which may offer more embolic material penetrating into the nidus of AVM, but additional work is needed to validate this technique.

Periprocedural symptomatic intracranial hemorrhage (sICH) unrelated to coil embolization of intracranial aneurysm has been rarely reported. The incidence and characteristics of this complication remain unclear. This study was designed to elucidate the incidence and characteristics of periprocedural sICH unrelated to coiling of intracranial aneurysm, and to explore the possible mechanisms underlying this complication. Included in this retrospective study were 1287 patients with 1394 aneurysms who were treated with coil embolization (476 patients with stent assistance and 811 patients without stents) between May 2008 and August 2017. All procedure-unrelated sICHs that occurred within 30 days after coiling were selected. The technical details of the procedure, clinical characteristics, and medical therapy were recorded. A total of 6 patients developed periprocedural sICH unrelated to coil embolization. All these six patients underwent stent-assisted coiling (SAC). Therefore, there was a 1.3% (6/476) procedure-unrelated sICH rate of SAC and 0% (0/811) in patients underwent coiling without stent during the periprocedural period (P = 0.005, RR 0.987; 95% CI, 0.977–0.997). These phenomena occurred more often in patients who received SAC for ruptured aneurysms vs patients underwent this technique for unruptured aneurysms (2.0 vs 0.7%, P = 0.390, RR 2.896; 95% CI, 0.525–15.968). All these phenomena occurred within 7 days after coiling, and resulted in one mortality, one unfavorable outcome (mRS Score 3), and other four favorable outcomes (mRS Scores 0–2) at 90 days after procedure. Our findings suggest that the procedure-unrelated sICH, though less frequent, may exist following stent-assisted coiling of intracranial aneurysm during the periprocedural period. Extra caution may be warranted in patients who were treated with SAC for ruptured aneurysms.

Intracranial hypertension (IH) may be misdiagnosed owing to the lack of typical imaging features and pathological confirmation of the sinus lesions. The authors report the use of percutaneous endovascular biopsy (PEB) for the diagnosis of IH in patients with venous sinus lesions. A total of 9 patients (age 46 ± 9 years) underwent PEB between June 2016 and August 2017. All patients underwent lumbar puncture and contrast-enhanced MRI before the procedure. PEB was technically successful in 6 patients. No intra- or postprocedural complications occurred. The confirmed lesions were meningioma in 2 patients and fibrous thrombus in 4 patients. All patients received individualized treatment. PEB of venous sinus lesions is a safe and efficient method to establish an early diagnosis and appropriate treatment in patients with IH.

The paper discusses the fatigue design theory of pressure vessels. For pressure vessel loads absorbed (pressure, temperature, earthquake, wind, snow, etc.) have significant stochastic dynamic characteristics and coupling characteristics, fatigue life analysis of pressure vessels based on random load history is proposed. Discusses in detail the random load spectrum rain flow counting process, the linear damage theory and fatigue life analysis. The new structure reactor of synthesis system fatigue life is calculated, the results show that the fatigue life and the design life of equipment vary widely, the need to improve pressure fluctuations of the synthesis of system.

A novel ice monitoring system for the overhead transmission lines based on fiber Bragg grating (FBG) sensing is proposed in this paper. Compared to the existing systems, this system has several unique advantages, such as unnecessary power supply onsite, excellent ability for avoiding electromagnetic interference, and long lifespan. First, two near-elliptical-shaped concavities with FBG in each side are designed on the column structure to improve accuracy in measuring eccentric load. Then, a high reliability and high resolution tilt sensing section is developed based on a beam of uniform strength where an FBG is fixed on. Finally, an unforced FBG is placed in the sensor to solve the cross-sensitivity of strain and temperature in FBG sensing. Tension and angle experiments are conducted in our laboratory to calibrate the sensor. The tension experiment results indicate that the sensor is sensitive to tension, and the sensitivity and resolution of the sensor are 0.0413 pm/N and 24.21 N. The results of the tilt angle experiment show that the sensitivity and resolution of the sensor is 16.17 pm/° and 0.0619°. The temperature effect on the tension and angle measurement, evaluated by putting the sensor in an oven, is less than ±0.3% and ±0.38% separately. A 250-h outdoor experiment was carried out in the testing field, and the results prove the sensor can work properly in harsh environments and no creep is observed during the experiment.

Disconnector switching operations in large gas-insulated switchgear (GIS) systems may produce very fast transient overvoltages (VFTOs), causing high electric stress to other apparatuses in the substation, such as power transformers. This paper presents a VFTO measuring technique based on a transformer bushing sensor, which consists of the transformer bushing (C1) and a capacitor sensor (C2) installed at the test tap of transformer bushing. In order to solve the problem of the frequency limitation of the transformer bushing sensor for measuring VFTO, a convolution model on the square-wave response of the transformer bushing sensor is introduced to obtain the frequency response of the transformer bushing sensor, and a deconvolution model based on the incremental Wiener filter is applied to reconstruct the input transient voltage waveform at the tip of the bushing by using the output signals from the bushing sensor. A 110-kV transformer bushing sensor and a fast transient overvoltage source are built in our laboratory. The results from the laboratory indicate that a transient voltage can be measured correctly based on our technique with the 110-kV transformer bushing sensor. A 750-kV transformer bushing sensor is built in a 750-kV substation. The measuring results from the 750-kV substation by using our technique show that the peak value of the VFTO produced by the disconnector (AIS) switching off operations is about 775 kV, and the dominant oscillating frequencies of the VFTO are 3.5 MHz, 1.6 MHz, and 650 kHz.

Background With the significant improvement in the survival of patients with nasopharyngeal carcinoma (NPC) undergoing radiotherapy and the growing availability of the sophisticated imaging modalities, the number of radiation encephalopathy (RE) cases relating to NPC radiotherapy is increasing. In this study, we investigated the metabolic and density changes of the compromised brain tissues during delayed RE using a positron-emission tomography-computed tomography (PET/CT) to provide clinical evidences for the diagnosis of delayed RE following radiotherapy for NPC. Methods The PET/CT manifestations and the clinical data of 53 pathologically confirmed NPC patients with delayed RE following radical radiotherapy and 15 healthy volunteers were investigated. The standardized uptake values (SUV) of the bilateral temporal lobes, the occipital lobe and the brain stem were measured respectively; and then the metabolic reduction rate of 88 temporal lobes and 13 brain stems were calculated for a statistical comparison between the two groups. Results The earliest case of delayed RE in the investigated patients occurred 1.5 years after radiotherapy. Delayed RE frequently involved the inferior temporal lobe. For patients with delayed RE confirmed by clinical symptoms and imaging findings, PET maintained a 100% coincidence rate with CT; however, in the 25 temporal lobes of the 35 delayed RE patients, PET revealed obvious hypometabolic changes whereas CT displayed normal density. The incidence of brain stem metabolic reductions was 24.5% (13/53) in the investigated patients, including 4 patients with hypometabolic changes shown by PET and negative finding shown by CT. The incidence of granuloma adjacent to the hypometabolic region in the temporal lobe was 12.5% (11/88). Conclusion Delayed RE patients exhibit significant hypometabolic changes in the inferior temporal lobe, captured by PET much earlier than by CT. PET/CT offers a valuable means for the diagnosis of delayed RE in subacute stages and granuloma formation.

In order to evaluate students' learning quality scientifically and reasonably,This paper utilized the way of literatural material,questionnaire survey,contrast analysis,mathematical statistics and so on to analysis synthetically on content ,standard and method of primary and secondary school's sports and healthy curriculum.The author had constructed evaluation system of learning quality by four first-level indexes.It mainly includes evaluation method, function, way and standard and so on. KEYWORD: Sports and Healthy Curriculum; Learning Quality; Evaluation System

A 41-year-old male patient was admitted to the General Hospital of Guangzhou Military Command due to upper abdominal pain persisting for 12 h. Computed tomography (CT) and positron emission tomography/CT scans revealed multiple soft-tissue shadows in the abdominal cavity, peritoneum and Glisson's capsule, but the metabolic activity was at normal levels. A small area of low-density shadows near the tail of the pancreas and multiple shadows of enlarged lymph nodes were identified around the porta hepatis and the pancreas, with a mildly increased metabolic activity. On the basis of the CT images the patient was diagnosed with pancreatitis. Radionuclide imaging showed the absence of the spleen from its normal position (following splenectomy), but abnormal phagocytosis of multiple red blood cells was observed in the abdomen, which was diagnosed as ectopic splenic autotransplantation (ESAT). The patient subsequently recovered well following symptomatic treatment. ESAT in trauma patients requires urgent surgery in order to remove the damaged spleen and artificially cultivate partial splenic tissue.

Ground conductor is easily broken when ice accumulates on it. Thus a novel Fiber Bragg Grating (FBG) sensor is proposed to measure the tension of the ground conductor to warning the danger. The factors affecting the sensitivity of the sensor are studied. The results of tension experiment indicate the sensitivity and resolution of the sensor are 0.2286pm/N and 2.18N respectively, and both of them can be easily altered by the equation proposed. The temperature effect on the measurement, which is caused by the crosstalk of FBG, is reduced by setting a zero-force FBG. The error of the sensor caused by temperature, evaluated by putting the sensor in an oven, is lower than 10 pm from −30 °C to 50 °C. An ice simulation platform is build in our laboratory, the results show the relative error of the simulated ice load calculated by the output of the sensor is lower than 5%.

Ice monitoring on the overhead transmission lines is very important to insure the power grid safe during the ice disaster. To solve the electromagnetic interference, a tension sensor based on Fiber Bragg Grating is developed to measure the tension of the power transmission line. The sensitivity of the sensor is 0.2286 pm/N calibrated with a test machine. The relative error of the load and sag, measured by the FBG sensing system, are smaller than 5% and 2% respectively based on our ice simulation system.

Disconnector operations in GIS may generate very fast transient overvoltage (VFTO), which is characterized by its high peak value, short rise time, and high frequencies. Mostly, researches on VFTO are focusing on the apparatus involving in the active circuit. However, VFTO may pass through open devices by electromagnetic coupling. To measure VFTO under this situation, lots of field experiments have been carried out in a 750 kV substation. VFTO is measured at the test tap of the high voltage reactor bushing, using the sensor we developed. In one of the experiments, the breaker is kept open, VFTO is generated by disconnector operations (in AIS) on one side of the breaker and measured on the other side. Results show that under this situation, VFTO could reach the peak values of about 55 kV and - 70 kV, the main oscillation frequencies are about 236 kHz, 535 kHz and 1.59 MHz. To verify this case further, computer simulation has also been carried out in the laboratory with the help of ATP. The results agree with each other well.

A capacitive sensor has been developed for the measurements of very fast transient over-voltages (VFTO) in GIS. Step response measurement was performed on the sensor. It is shown from the test that the settling time is less than 20 ns and the response time is less than 2ns, suitable to the IEC1321-1. The sensor has been calibrated by power frequency voltage, impulse voltage, the division ratio of the power frequency voltage is almost as the same as that of the impulse voltage, the maximum error was less than 1.3%. The sensor was mounted in a 126KV GIS test setup to measure the transients produced by the air gap discharges. The measurement results demonstrated that the sensor is able to measure the transients with 10ns rise-time successfully.

Disconnector switching operations in large gas insulated switchgear (GIS) systems may cause very fast transients overvoltages (VFTO), which produce dielectric stress to transformer connecting with the disconnector. A VFTO bushing sensor is developed to measure the VFTO at the transformer entrance. Since the high frequency ratio of the bushing sensor is not constant, calibration before the field measurement is needed. Based on the convolution model and step response, a new calibration method is used to identify the frequency response of the bushing sensor. Calibration of an 110 kV rated bushing sensor is carried on in our laboratory to investigate the effectiveness of this method, and the calibrated results agree well with the amplitude-response gained by frequency sweep test, which demonstrates the calibrating method can be applied in VFTO bushing sensor calibration. Calibration of an UHV rated bushing sensor is processed in a factory and the frequency response of the sensor is given at the end of the paper.