Enhanced Seamless Video Fusion: A Convolutional Pyramid-Based 3D Integration Algorithm.

Video fusion aims to synthesize video footage from different sources into a unified, coherent output. It plays a key role in areas such as video editing and special effects production. The challenge is to ensure the quality and naturalness of synthetic video, especially when dealing with footage of different sources and qualities. Researchers continue to strive to optimize algorithms to adapt to a variety of complex application scenarios and improve the effectiveness and applicability of video fusion. We introduce an algorithm based on a convolution pyramid and propose a 3D video fusion algorithm that looks for the potential function closest to the gradient field in the least square sense. The 3D Poisson equation is solved to realize seamless video editing. This algorithm uses a multi-scale method and wavelet transform to approximate linear time. Through numerical optimization, a small core is designed to deal with large target filters, and multi-scale transformation analysis and synthesis are realized. In terms of seamless video fusion, it shows better performance than existing algorithms. Compared with editing multiple 2D images into video after Poisson fusion, the video quality produced by this method is very close, and the computing speed of the video fusion is improved to a certain extent.

Polarimetric calibration method for the fore-optics of a channeled spectropolarimeter.

A channeled spectropolarimeter is a powerful tool for the simultaneous measurement of the intensity, spectral, and polarization information of a target. However, the fore-optics introduce additional polarization information, which leads to inaccurate reconstruction of the Stokes parameters. In this study, we propose a simple method for polarimetric calibration and Stokes parameters reconstruction for a fieldable channeled spectropolarimeter. The polarization effects of the fore-optics and phase factors of the high-order retarders at varying view angles are considered and calibrated independently using a single reference beam. Moreover, the misalignment of the retarders is also considered. Simulation results demonstrate that the polarization effects of fore-optics can be precisely determined, enhancing the measurement accuracy of the Stokes parameters by approximately an order of magnitude. The effectiveness of the proposed method is also verified experimentally.

Defect detection and response non-uniformity correction of a monocentric camera based on fiber optic relay imaging.

The monocentric camera based on fiber relay imaging offers benefits of light weight, compact size envelope, vast field of view, and high resolution, which can fully fulfill the index requirements of space-based surveillance systems. However, the fiber optic plate's (FOP) defects will result in the loss of imaging data, and the FOP's discrete structural features will exacerbate the imaging's non-uniformity. A global defect detection approach based on manual threshold segmentation of saturated frames is suggested to detect FOP defect features. The suggested method's efficacy and accuracy are confirmed when compared to the classical Otsu algorithm. Additionally, through tests, the relative imaging response coefficients of each pixel are identified, the response non-uniformity of the pixels is corrected, and the whole image non-uniformity drops from 10.01% to 0.78%. The study in this paper expedites the use of fiber relay imaging-based monocentric cameras in the field of space-based surveillance, and the technique described in this paper is also appropriate for large-array optical fiber coupled relay image transmission systems.

Real-time on-orbit image quality improvement for a wide-field imaging system with detector arrays.

Wide-field imaging systems are faced with the problem of massive image information processing and transmission. Due to the limitation of data bandwidth and other factors, it is difficult for the current technology to process and transmit massive images in real-time. With the requirement for fast response, the demand for real-time on-orbit image processing is increasing. In practice, nonuniformity correction is an important preprocessing step to improve the quality of surveillance images. This paper presents a new real-time on-orbit nonuniform background correction method, which only uses the local pixels of a single row output in real-time, breaking the dependence of the traditional algorithm on the whole image information. Combined with the FPGA pipeline design, when the local pixels of a single row are read out, the processing is completed, and no cache is required at all, which saves the resource overhead in hardware design. It achieves microsecond-level ultra-low latency. The experimental results show that under the influence of strong stray light and strong dark current, our real-time algorithm has a better image quality improvement effect compared with the traditional algorithm. It will greatly help the on-orbit real-time moving target recognition and tracking.

National Brain Tumour Registry of China (NBTRC) statistical report of primary brain tumours diagnosed in China in years 2019-2020.

Background: The lack of a well-designed brain tumour registry with standardized pathological diagnoses in underdeveloped countries hinders the ability to compare epidemiologic data across the globe. The National Brain Tumour Registry of China (NBTRC), created in January 2018, is the first multi-hospital-based brain tumour registry in China. Patient data reported to the NBTRC in years 2019-2020 were assessed. Methods: Tumour pathology was based on the 2016 World Health Organization (WHO) classification of tumours of the central nervous system and ICD-O-3. The anatomical site was coded per the Surveillance, Epidemiology, and End Results (SEER) solid tumour module (version of July 2019). The cases were tabulated by histology and anatomical site. Categorical variables were reported as numbers (percentages). The distribution of tumours by age (0-14, 15-19, 20-39, 40-64, and 65+ years) was analysed. Findings: There were a total of 25,537 brain tumours, foremost among them meningioma (23.63%), followed by tumours of the pituitary (23.42%), and nerve sheath tumours (9.09%). Glioblastoma, the most common and lethal form of primary brain cancer in adults, represented 8.56% of all cases. Of note, 6.48% of the malignant tumours were located in the brain stem. The percentage of malignant brain tumours decreased with increasing age, 24.08% in adults (40+ years), 30.25% in young adults (20-39 years), 35.27% in adolescents (15-19 years), and 49.83% in children (0-14 years). Among the 2107 paediatric patients, the most common sites were ventricle (17.19%), brainstem (14.03%), pituitary and craniopharyngeal duct (13.4%), and cerebellum (12.3%), a distribution that differed from that of the entire cohort. The histology distribution was also unique in children, with glioblastoma much less incident compared to the whole cohort (3% vs. 8.47%, p < 0.01). 58.80% of all patients chose higher-level neurosurgical hospitals outside of their province of residence. The median in-hospital length of stay (LOS) for the various pathologies ranged from 11 to 19 days. Interpretation: The histological and anatomical site distribution of brain tumours in the NBTRC was statistically different in the subgroup of children (0-14 years). Patient choice of pursuing trans-provincial treatment was common and the in-hospital LOS was longer compared to that reported in similar European and American patient populations, which merits further attention. Funding: The National Key Research and Development Program of China (2015BAI12B04, 2013BAI09B03, 2014BAI04B01, and 2021YFF1201104) and Chinese National Natural Science Foundation of China (81971668).

In-Orbit Calibration of Phase Retardance for Channeled Spectropolarimeter.

The phase retardance of the optical system (PROS) is a crucial factor limiting the accuracy of the Stokes vector reconstruction for the channeled spectropolarimeter. The dependence on reference light with a specific angle of polarization (AOP) and the sensitivity to environmental disturbance brings challenges to the in-orbit calibration of PROS. In this work, we propose an instant calibration scheme with a simple program. A function with a monitoring role is constructed to precisely acquire a reference beam with a specific AOP. Combined with numerical analysis, high-precision calibration without the onboard calibrator is realized. The simulation and experiments prove the effectiveness and anti-interference characteristics of the scheme. Our research under the framework of fieldable channeled spectropolarimeter shows that the reconstruction accuracy of S2 and S3 in the whole wavenumber domain are 7.2 × 10-3 and 3.3 × 10-3, respectively. The highlight of the scheme is to simplify the calibration program and ensure that the PROS high-precision calibration is not disturbed by the orbital environment.

Epithelial-Mesenchymal Transition Expression Profile Stratifies Human Glioma into Two Distinct Tumor-Immune Subtypes.

Glioma is the primary tumor with the highest incidence and the worst prognosis in the human central nervous system. Epithelial-mesenchymal transition (EMT) and immune responses are two crucial processes that contribute to it having the worst prognosis. However, a comprehensive correlation between these two processes remains elusive. The mRNA expression profiles and corresponding clinical data of patients with glioma were downloaded from public databases. EMT-related genes were collected and provided in the dbEMT database. Risk scores, Lasso regression, and enrichment analysis were conducted for functional validation. In our study, we used unsupervised clustering of EMT gene expression profiles to classify gliomas into two subtypes. We assessed the reliability of this classification system by testing it in three independent cohorts. Each subtype had different clinical and immune system characteristics. The study suggests a possible link between EMT and immune responses in gliomas.

Targeting the Tumor Immune Microenvironment Could Become a Potential Therapeutic Modality for Aggressive Pituitary Adenoma.

OBJECT: This study aimed to explore the relationship between the aggressiveness and immune cell infiltration in pituitary adenoma (PA) and to provide the basis for immuno-targeting therapies. METHODS: One hundred and three patients with PA who underwent surgery at a single institution were retrospectively identified. The infiltration of macrophages and T-lymphocytes was quantitatively assessed. RESULTS: The number of CD68+ macrophages was positively correlated with Knosp (p = 0.003) and MMP-9 expression grades (p = 0.00). The infiltration of CD163+ macrophages differed among Knosp (p = 0.022) and MMP-9 grades (p = 0.04). CD8+ tumor-infiltrating lymphocytes (TILs) were also positively associated with Knosp (p = 0.002) and MMP-9 grades (p = 0.01). Interestingly, MGMT expression was positively correlated with MMP-9 staining extent (p = 0.000). The quantities of CD8+ TILs (p = 0.016), CD68+ macrophages (p = 0.000), and CD163+ macrophages (p = 0.043) were negatively associated with MGMT expression levels. The number of CD68+ macrophages in the PD-L1 negative group was significantly more than that in the PD-L1 positive group (p = 0.01). The rate of PD-L1 positivity was positively correlated with the Ki-67 index (p = 0.046) and p53 expression (p = 0.029). CONCLUSION: Targeted therapy for macrophages and CD8+ TILs could be a helpful treatment in the future for aggressive PA. Anti-PD-L1 therapy may better respond to PAs with higher Ki-67 and p53 expression and more infiltrating CD68+ macrophages. Multiple treatment modalities, especially combined with immunotherapy could become a novel therapeutic strategy for aggressive PA.

Prediction of soil properties based on characteristic wavelengths with optimal spectral resolution by using Vis-NIR spectroscopy.

Visible and near-infrared (Vis-NIR) spectroscopy technique has been recognized as a cost-effective, rapid, non-destructive alternative to traditional soil physicochemical analysis to estimate soil properties over the past few decades. Most efforts are devoted to the selection of characteristic wavelengths to eliminate the uninformative variables while ignoring the impact of the spectral resolution of these wavelengths on the prediction accuracy of soil properties. Therefore, the originality of this study is to identify the characteristic wavelengths with the optimal spectral resolution to achieve a better prediction performance. A 'two-step' wavelength selection method was proposed to select the characteristic wavelengths. Then, we simulated 1 nm-100 nm spectral resolution based on the spectral database measured by a portable ASD spectroradiometer and adopted the artificial bee colony (ABC) algorithm to further improve the prediction ability by configuring the most appropriate spectral resolution for each characteristic wavelength. The soil databases for this study consisted of 112 soil samples collected from Songnen Plain area in northeast China, and partial least squares regression (PLSR) was used to establish relations between pretreatment spectra and soil properties, including soil organic matter (SOM), available phosphorus (AP), and available potassium (AK). The independent validation results of this strategy effectively favored the prediction accuracy of SOM ( [Formula: see text] ), AP ( [Formula: see text] ), and AK ( [Formula: see text] ) compared with the PLSR models developed with full-spectra. In general, the method presented in this study suggested a framework for selecting characteristic wavelengths with optimal spectral solutions to predict SOM, AP, AK, and perhaps some other soil properties. The results of this paper also will provide guidance for the development of the low-cost specialized spectroscopic instruments for soil properties measurement.

Clinical Characteristics and Prognostic Risk Factors of Parasellar Chondrosarcoma.

Background: Parasellar chondrosarcomas are extremely rare. This study describes the characteristics of parasellar chondrosarcoma and analyzes the risk factors and prognosis based on the resection degree. Methods: Fifteen patients with pathologically diagnosed parasellar chondrosarcoma were retrospectively analyzed for the clinical data, surgical methods, and prognosis to identify relationships between the surgical resection degree, tumor recurrence, and imaging characteristics. Results: Twelve patients had eye dysfunction and ptosis. Differentiation from other parasellar tumors by imaging is difficult. The preoperative Karnofsky Performance Scale (KPS) score positively correlated with the tumor resection degree (p = 0.026) and negatively correlated with the maximum tumor diameter (p = 0.001). Tumor recurrence negatively correlated with the resection degree (p = 0.009). The postoperative KPS score positively correlated with the preoperative KPS score (p < 0.001) and tumor resection degree (p = 0.026), and negatively correlated with the maximum tumor diameter (p = 0.016) and age (p = 0.047). An improved KPS score positively correlated with the tumor resection degree (p = 0.039). Patients who underwent total resection of the chondrosarcoma had longer progression-free survival than those who underwent partial resection (p = 0.0322). Conclusion: Parasellar chondrosarcomas are difficult to resect completely. Preoperative KPS score is an important factor for the degree of resection. KPS score, age, maximum tumor diameter, and resection degree may be important prognostic factors.

DICER1-associated central nervous system sarcoma with neural lineage differentiation: a case report.

BACKGROUND: DICER1-associated central nervous system sarcoma (DCS) without evidence of other cancer-related syndromes is rare. Though the morphology of DCS was highly variable, the immunophenotype was predominant myogenic phenotype. Other lineage markers were consistently negative. CASE PRESENTATION: We report a case of DCS with neurogenic differentiation proved by immunohistochemical staining and whole-exome sequencing (WES). An 8-year-old female patient presented with 8-day history of headache, nausea and vomiting. Magnetic resonance imaging (MRI) revealed a heterogeneous mass in the left parietal lobe. The patient underwent the craniotomy via left parietal approach to resect the tumor completely. Histologically, the tumor predominately showed fibrosarcoma-like spindle cells with obvious cytoplasmic eosinophilic globules. Immunohistochemically, the tumor stained positively for DICER1, Desmin, and several neurogenic markers. DICER1 somatic hotspot mutation was confirmed by WES, as well as TP53 and RAF1 mutations which were commonly found in DCS, and other sarcoma-associated genes including AR, AXL and ETV5 mutations. Subsequently, the result of Gene Ontology (GO) analysis showed that the mutated genes in this case were involved in neuron development. All of these findings indicated the diagnosis of DCS with neurogenic differentiation. Postoperatively, the patient received high-dose radiotherapy (60 Gy) and chemotherapy. There was no MRI evidence of tumor recurrence at the 21-month postoperative follow-up. CONCLUSIONS: This unusual DCS case with neuronal differentiation is an important addition to the immuno-phenotypic spectrum of DCS. Although the prognosis for DCS is poor, gross tumor resection with high dose radiotherapy and chemotherapy may assist in prolonging survival.

Development and Validation of a Nomogram Model Based on Hematological Indicators for Predicting the Prognosis of Diffused Gliomas.

Background: Diffused gliomas are aggressive malignant brain tumors. Various hematological factors have been proven to predict the prognosis of patients with gliomas. The aim of this study is to integrate these hematological markers and develop a comprehensive system for predicting the prognosis of patients with gliomas. Method: This retrospective study included 723 patients pathologically diagnosed with diffused gliomas. Hematological indicators were collected preoperatively, including neutrophil-to-lymphocyte ratio (NLR), lymphocyte-monocyte ratio (LMR), platelet-to-lymphocyte ratio (PLR), albumin globulin ratio (AGR), platelet distribution width (PDW), red blood cell distribution width (RDW), fibrinogen (FIB), and prognostic nutritional index (PNI). Least absolute shrinkage and selection operator (LASSO) Cox was applied to screen the hematological indicators for a better prediction of patients' prognosis and to build an inflammation-nutrition score. A nomogram model was developed to predict the overall survival (OS), which included age, tumor grade, IDH-1 mutations, and inflammation-nutrition score. Result: Patients were randomly divided into a primary cohort (n = 509) and a validation cohort (n = 214). There was no difference in age and IDH-1 mutation frequency between the cohorts. In the primary cohort, NLR, LMR, AGR, FIB, and PNI were selected to build an inflammation nutrition score. Patients with a high-risk inflammation-nutrition score had a short median OS of 17.40 months compared with 27.43 months in the low-risk group [HR 2.54; 95% CI (1.91-3.37); p < 0.001]. Moreover, age, tumor grade, IDH-1 mutations, and inflammation-nutrition score were independent prognostic factors in the multivariate analysis and thus were included in the nomogram model. The nomogram model showed a high prediction value with a Harrell's concordance index (C-index) of 0.75 [95% CI (0.72-0.77)]. The validation cohort supported these results. Conclusion: The prognostic nomogram model provided a high prognostic predictive power for patients with gliomas.

Channeled spectropolarimeter with arbitrary retarder orientation settings.

A channeled spectropolarimeter can simultaneously obtain intensity, spectral, and polarization information. In the traditional model, the retarders must be oriented at specific angles. However, misalignments of the retarders are inevitable during assembly, and the status of the retarders is sensitive to environmental perturbations, which affects the performance of the channeled spectropolarimeter. In this study, a general channeled spectropolarimeter model was derived, in which the retarder orientations can be arbitrary and unknown. Meanwhile, the system is unaffected by environmental perturbation because it can self-calibrate to avoid fluctuations in the retarder orientations and phase retardations. The effectiveness and robustness of the model were verified through simulations and experiments.

Torque Ripple Suppression of Brushless DC Motor Drive System Based on Improved Harmonic Injection Active Disturbance Rejection Control.

The positioning accuracy and speed stability of the brushless DC motor (BLDC motor), as the drive element of the optomechanically scanned system (OMSS), are closely interrelated to the final imaging quality of the system. Active disturbance rejection control (ADRC) with strong anti-interference ability, fast response and good robustness is one of the extensively used control strategies. However, the performance of ADRC working in a complicated environment will be limited due to the controller structure, parameter tuning and the influence of multi-source nonlinear disturbance. Therefore, an improved ADRC method is proposed, which can switch between 'point-to-point control mode' and 'stable speed control mode' according to the system requirements. To further suppress the torque ripple and improve the control performance of the system, an improved harmonic injection scheme is added, and the parameters of improved ADRC are tuned by a slime mould algorithm based on a Levy flight operator (LF-SMA). The stability of the proposed ADRC is proved by Lyapunov stability theory. The experimental results show that the proposed control scheme could be available to reduce the torque ripple of the system.

Postoperative hydrocephalus is a high-risk lethal factor for patients with low-grade optic pathway glioma.

OBJECTIVES: To explore the prognostic factors of patients with low-grade optic pathway glioma (OPG) and the optimal treatment to reduce the incidence of postoperative hydrocephalus. PATIENTS AND METHODS: This single-center study retrospectively analyzed data from 66 patients with OPGs who underwent surgery. The patients were followed, and overall survival (OS) and progression-free survival (PFS) were determined. The effects of different treatments on the hydrocephalus of patients were compared. RESULTS: Postoperative hydrocephalus was identified as a factor to increase the risk of mortality by 1.99-fold (p = .028). And, 5-year survival rate was significantly lower among patients with postoperative hydrocephalus (p = .027). The main factors leading to preoperative hydrocephalus in patients are large tumor volume and invasion into the third ventricle. Gross total resections (GTR) could reduce the risk of long-term hydrocephalus (p = .046). Age younger than 4 years (p = .046) and tumor invasion range/classification (p = .029) are the main factors to reduce the five-year survival rate. Postoperative radiotherapy (RT) and chemotherapy (CT) had no significant effects on OS. Extraventricular drainage (EVD) was not associated with perioperative infection (p = .798 > .05) and bleeding (p = .09 > .05). Compared with 2 stage surgery (external ventricular drainage or ventriculoperitoneal shunt (VPS) was first placed, followed by tumor resection), 1 stage surgery (direct resection of tumor) had no complication increase. CONCLUSIONS: Postoperative hydrocephalus is mostly obstructive hydrocephalus, and it is an important factor that reduces the OS of patients with low-grade OPGs. Surgery to remove the tumor to the greatest extent improves cerebrospinal fluid circulation is effective at reducing the incidence postoperative hydrocephalus. For patients whose ventricles are still dilated after surgery, in addition to considering poor ventricular compliance, they need to be aware of the persistence and progression of hydrocephalus.

Expression of TCF7L2 in Glioma and Its Relationship With Clinicopathological Characteristics and Patient Overall Survival.

Background: The TCF7L2 gene is known as transcription factor 7-like 2 which has been identified as a novel transcription factor epithelial-mesenchymal transition (EMT) in tumor cells at 10q25.3. TCF7L2 may affect cancer progression and plays a central role in cancer proliferation, migration, and invasion. However, its clinical and prognostic value have not been researched in glioma. The purpose of our study was to research TCF7L2 expression and evaluate the clinical value of prognosis. Method: We collected glioma specimens including low-grade glioma (n = 46) and glioblastoma (n = 51) from September 2015 to September 2017. Expression of TCF7L2 in 97 specimens was detected by quantitative real-time PCR (qRT-PCR). The chi-square test was applied to analyze the relationship between TCF7L2 expression and clinicopathological characteristics. The overall survival (OS) was estimated by log-rank tests among strata, and the survival curves were drawn by Kaplan-Meier. Univariate and multivariate analysis were utilized to analyze the relationship between prognosis and clinicopathological characteristics including TCF7L2 expression. Results: Compared with the low-grade glioma group, the expression of TCF7L2 was significantly increased in the glioblastoma group (p = 0.001). TCF7L2 overexpression was associated with higher WHO grade (p = 0.001), isocitrate dehydrogenase (IDH) wild-type (p = 0.001), and lack of O(6)-methylguanine-DNA methyltransferase (MGMT) methylation (p = 0.001). Moreover, Kaplan-Meier analysis proved that overexpressed TCF7L2 was associated with poor OS (p = 0.010). The multivariate analysis suggested that TCF7L2 expression was an independent prognostic factor (p = 0.020). Conclusions: Our research proved that TCF7L2 was overexpressed in glioblastoma, and related with tumor long-term prognosis, which, therefore, could be an independent prognostic factor for glioma patients.

Spatially modulated snapshot computed tomographic polarization imaging spectrometer.

Herein, a spatially modulated snapshot computed tomographic polarization imaging spectrometer (SMSCTPIS) is proposed. This instrument can obtain spatial, intensity, and polarization information of different wavelengths of a target simultaneously. It can also alleviate certain limitations of the spatially modulated snapshot imaging polarimeter (SMSIP) based on a Savart polarizer, which cannot obtain information of different wavelengths in a single measurement. Further, it can also mitigate the need to frequently replace the filters of SMSIPs for different detection wavelengths. The paper introduces the structure and principle of the SMCTPIS first, followed by experiments confirming its accuracy. Finally, the experimental results are analyzed, and conclusions are drawn.

Alterations in the RTK/Ras/PI3K/AKT pathway serve as potential biomarkers for immunotherapy outcome of diffuse gliomas.

BACKGROUND: Diffuse gliomas are the most common malignant brain tumors, and immune checkpoint inhibitors have limited therapeutic effects against this cancer. Three oncogenic pathways are altered in diffuse gliomas: the RTK/Ras/PI3K/AKT signaling, TP53, and RB pathways. Although these pathways may affect the tumor immune microenvironment, their association with immunotherapy biomarkers remains unclear. METHODS: We used copy number variation and mutation data to stratify patients with specific oncogenic signaling alterations, and evaluated their correlation with predictive immunotherapy biomarkers, including tumor mutation burden (TMB), immune cytolytic activity (CYT), tumor purity, and tumor-infiltrating CD8+ T cells. Immune checkpoint expression and interferon-γ signaling activity were also compared in these samples. RESULTS: We identified differentially expressed genes in three distinct oncogenic pathways. Gene ontology analysis of these genes revealed the involvement of RTK/Ras/PI3K/AKT-associated genes in immune and inflammatory responses. Moreover, significantly elevated TMB, CYT, and numbers of CD8+ T cells and decreased tumor purity were correlated with altered RTK/Ras/PI3K/AKT signaling. Single cell sequencing also confirmed that this tumor subgroup had increased immune checkpoint expression and interferon-γ signaling activity. Immune phenotyping based on the presence of CD274 and TMB or CD274 and CD8 T+ cells indicated that tumors with altered RTK/Ras/PI3K/AKT pathways represent a beneficial subtype and are associated with improved survival. CONCLUSION: Altered RTK/Ras/PI3K/AKT signaling and immunotherapy biomarkers are strongly correlated in gliomas. Gliomas with altered expression of RTK/Ras/PI3K/AKT pathway components may be sensitive to immunotherapy. A combination of small-molecule kinase inhibitors and immunotherapy is proposed for this subgroup of tumors.

The role of clinical factors and immunocheckpoint molecules in the prognosis of patients with supratentorial extraventricular ependymoma: a single-center retrospective study.

PURPOSE: Supratentorial extraventricular ependymoma (SEE) is a rare subset of ependymomas located in the supratentorial parenchyma, and little is known regarding its management and prognosis. Our study aimed to reveal the prognostic factors in patients with SEE and the roles of programmed death ligand-1 (PD-L1), programmed cell death protein 1 (PD-1), Ki-67, and neural cell adhesion molecule L1 (L1CAM) in predicting these patients' outcomes. METHODS: We retrospectively studied the clinical features and prognostic factors in 48 patients with SEE admitted to our center from April 2008 to October 2018. Tissue slides were constructed from patient samples, and PD-L1, PD-1, Ki-67, and L1CAM expression levels were evaluated by immunohistochemistry. RESULTS: Patients with gross total resection (GTR) had better progression-free survival than patients with subtotal resection (STR). Moreover, the recurrence hazard ratios in patients with STR at 3, 5, and 10 years were 8.746, 6.866 and 3.962 times those of patients with GTR, respectively. PD-L1 positivity predicted worse progression-free survival, while the recurrence hazard ratios for patients with PD-L1 positivity at 3, 5, and 10 years were 10.445, 5.539, and 3.949 times those of patients with PD-L1 negativity, respectively. Multivariate analysis revealed that PD-L1 expression and GTR could independently predict outcomes in patients with SEE. CONCLUSION: PD-L1 expression was an independent and more readily obtained predictor of outcomes, representing a simple and reliable biological prognostic factor for patients with SEE. Further studies are needed to explore PD-L1 inhibitor treatment for patients with ependymoma. CLINICAL TRIAL REGISTRATION: No clinical trials were performed in the study.

Typical subdural contrast effusion secondary to endovascular treatment of a pediatric pial arteriovenous fistula.

Subdural contrast effusion secondary to endovascular treatment is exceptionally rare and might be mistaken as subdural hematoma because of similar hyperattenuation on computer tomography. The authors present the case of a 13-month-old girl with a history of increased head circumference and developmental retardation. Cerebral digital subtraction angiography showed a high-flow pial arteriovenous fistula fed by multiple arteries on the right cerebellar surface, with occlusion of the right sigmoid sinus and severe stenosis of the left sigmoid sinus. Staged endovascular treatments were performed to eliminate the fistula. Follow-up head computer tomography scans performed 3 h after both procedures demonstrated typical high-density subdural effusion with computer tomography attenuation value similar to hemorrhage. These effusions did not aggravate the condition and disappeared spontaneously 32 h after the first treatment and 29 h after the second, respectively.