Connectomic insights into the impact of 1p/19q co-deletion in dominant hemisphere insular glioma patients.

Objectives: This study aimed to elucidate the influences of 1p/19q co-deletion on structural connectivity alterations in patients with dominant hemisphere insular diffuse gliomas. Methods: We incorporated 32 cases of left insular gliomas and 20 healthy controls for this study. Using diffusion MRI, we applied correlational tractography, differential tractography, and graph theoretical analysis to explore the potential connectivity associated with 1p/19q co-deletion. Results: The study revealed that the quantitative anisotropy (QA) of key deep medial fiber tracts, including the anterior thalamic radiation, superior thalamic radiation, fornix, and cingulum, had significant negative associations with 1p/19q co-deletion (FDR = 4.72 × 10-5). These tracts are crucial in maintaining the integrity of brain networks. Differential analysis further supported these findings (FWER-corrected p < 0.05). The 1p/19q non-co-deletion group exhibited significantly higher clustering coefficients (FDR-corrected p < 0.05) and reduced betweenness centrality (FDR-corrected p < 0.05) in regions around the tumor compared to HC group. Graph theoretical analysis indicated that non-co-deletion patients had increased local clustering and decreased betweenness centrality in peritumoral brain regions compared to co-deletion patients and healthy controls (FDR-corrected p < 0.05). Additionally, despite not being significant through correction, patients with 1p/19q co-deletion exhibited lower trends in weighted average clustering coefficient, transitivity, small worldness, and global efficiency, while showing higher tendencies in weighted path length compared to patients without the co-deletion. Conclusion: The findings of this study underline the significant role of 1p/19q co-deletion in altering structural connectivity in insular glioma patients. These alterations in brain networks could have profound implications for the neural functionality in patients with dominant hemisphere insular gliomas.

Survival outcome and predictors of WHO grade 2 and 3 insular gliomas: A classification based on the tumor spread.

OBJECTIVE: The study aimed to identify if clinical features and survival outcomes of insular glioma patients are associated with our classification based on the tumor spread. METHODS: Our study included 283 consecutive patients diagnosed with histological grade 2 and 3 insular gliomas. A new classification was proposed, and tumors restricted to the paralimbic system were defined as type 1. When tumors invaded the limbic system (referred to as the hippocampus and its surrounding structures in this study) simultaneously, they were defined as type 2. Tumors with additional internal capsule involvement were defined as type 3. RESULTS: Tumors defined as type 3 had a higher age at diagnosis (p = 0.002) and a higher preoperative volume (p < 0.001). Furthermore, type 3 was more likely to be diagnosed as IDH wild type (p < 0.001), with a higher rate of Ki-67 index (p = 0.015) and a lower rate of gross total resection (p < 0.001). Type 1 had a slower tumor growth rate than type 2 (mean 3.3%/month vs. 19.8%/month; p < 0.001). Multivariate Cox regression analysis revealed the extent of resection (HR 0.259, p = 0.004), IDH status (HR 3.694, p = 0.012), and tumor spread type (HR = 1.874, p = 0.012) as independent predictors of overall survival (OS). Tumor grade (HR 2.609, p = 0.008), the extent of resection (HR 0.488, p = 0.038), IDH status (HR 2.225, p = 0.025), and tumor spread type (HR 1.531, p = 0.038) were significant in predicting progression-free survival (PFS). CONCLUSION: The current study proposes a classification of the insular glioma according to the tumor spread. It indicates that the tumors defined as type 1 have a relatively better nature and biological characteristics, and those defined as type 3 can be more aggressive and refractory. Besides its predictive value for prognosis, the classification has potential value in formulating surgical strategies for patients with insular gliomas.

Epilepsy alters brain networks in patients with insular glioma.

AIMS: We intend to elucidate the alterations of cerebral networks in patients with insular glioma-related epilepsy (GRE) based on resting-state functional magnetic resonance images. METHODS: We collected 62 insular glioma patients, who were subsequently categorized into glioma-related epilepsy (GRE) and glioma with no epilepsy (GnE) groups, and recruited 16 healthy individuals matched to the patient's age and gender to form the healthy control (HC) group. Graph theoretical analysis was applied to reveal differences in sensorimotor, default mode, visual, and executive networks among different subgroups. RESULTS: No significant alterations in functional connectivity were found in either hemisphere insular glioma. Using graph theoretical analysis, differences were found in visual, sensorimotor, and default mode networks (p < 0.05). When the glioma located in the left hemisphere, the degree centrality was reduced in the GE group compared to the GnE group. When the glioma located in the right insula, the degree centrality, nodal efficiency, nodal local efficiency, and nodal clustering coefficient of the GE group were lower than those of the GnE group. CONCLUSION: The impact of insular glioma itself and GRE on the brain network is widespread. The networks altered by insular GRE differ depending on the hemisphere location. GRE reduces the nodal properties of brain networks than that in insular glioma.

Assessing Postoperative Motor Risk in Insular Low-Grade Gliomas Patients: The Potential Role of Presurgery MRI Corticospinal Tract Shape Measures.

BACKGROUND: Insular low-grade gliomas (LGGs) are surgically challenging due to their proximity to critical structures like the corticospinal tract (CST). PURPOSE: This study aims to determine if preoperative CST shape metrics correlate with postoperative motor complications in insular LGG patients. STUDY TYPE: Retrospective. POPULATION: 42 patients (mean age 40.26 ± 10.21 years, 25 male) with insular LGGs. FIELD STRENGTH/SEQUENCE: Imaging was performed using 3.0 Tesla MRI, incorporating T1-weighted magnetization-prepared rapid gradient-echo, T2-weighted space dark-fluid with spin echo (SE), and diffusional kurtosis imaging (DKI) with gradient echo sequences, all integrated with echo planar imaging. ASSESSMENT: Shape metrics of the CST, including span, irregularity, radius, and irregularity of end regions (RER and IER, respectively), were compared between the affected and healthy hemispheres. Total end region radius (TRER) was determined as the sum of RER 1 and RER 2. The relationships between shape metrics and postoperative short-term (4 weeks) and long-term (>8 weeks) motor disturbances assessing by British Medical Research Council grading system, was analyzed using multivariable regression models. STATISTICAL TESTING: Paired t-tests compared CST metrics between hemispheres. Logistic regression identified associations between these metrics and motor disturbances. The models were developed using all available data and there was no independent validation dataset. Significance was set at P < 0.05. RESULTS: Short-term motor disturbance risk was significantly related to TRER (OR = 199.57). Long-term risk significantly correlated with IER 1 (OR = 59.84), confirmed as a significant marker with an AUC of 0.78. Furthermore, the CST on the affected side significantly had the greater irregularity, larger TRER and RER 1, and smaller span compared to the healthy side. DATA CONCLUSION: Preoperative evaluation of TRER and IER 1 metrics in the CST may serve as a tool for assessing the risk of postoperative motor complications in insular LGG patients. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.

Exploring MGMT methylation-driven structural connectivity changes in insular gliomas: a tractography and graph theoretical analysis.

OBJECTIVES: This study aims to explore the relationship between the methylation levels of the O-6-methylguanine-DNA methyltransferase (MGMT) promoter and the structural connectivity in insular gliomas across hemispheres. METHODS: We analyzed 32 left and 29 right insular glioma cases and 50 healthy controls, using differential tractography, correlational tractography, and graph theoretical analysis to investigate the correlation between structural connectivity and the methylation level. RESULTS: The differential tractography results revealed that in left insular glioma, the volume of affected inferior fronto-occipital fasciculus (IFOF, p = 0.019) significantly correlated with methylation levels. Correlational tractography results showed that the quantitative anisotropy (QA) value of peritumoral fiber tracts also exhibited a significant correlation with methylation levels (FDR < 0.05). On the other hand, in right insular glioma, anterior internal part of the reticular tract, IFOF, and thalamic radiation showed a significant correlation with methylation levels but at a different correlation direction from the left side (FDR < 0.05). The graph theoretical analysis showed that in the left insular gliomas, only the radius of graph was significantly lower in methylated MGMT group than unmethylated group (p = 0.047). No significant correlations between global properties and methylation levels were observed in insular gliomas on both sides. CONCLUSION: Our findings highlight a significant, hemisphere-specific correlation between MGMT promoter methylation and structural connectivity in insular gliomas. This study provides new insights into the genetic influence on glioma pathology, which could inform targeted therapeutic strategies.

A preliminary study on corticospinal tract morphology in incidental and symptomatic insular low-grade glioma: implications for post-surgical motor outcomes.

OBJECTIVE: Our study aimed to investigate the shape and diffusion properties of the corticospinal tract (CST) in patients with insular incidental and symptomatic low-grade gliomas (LGGs), especially those in the incidental group, and evaluate their association with post-surgical motor function. METHODS: We performed automatic fiber tracking on 41 LGG patients, comparing macroscopic shape and microscopic diffusion properties of CST between ipsilateral and contralateral tracts in both incidental and symptomatic groups. A correlation analysis was conducted between properties of CST and post-operative motor strength grades. RESULTS: In the incidental group, no significant differences in mean diffusion properties were found between bilateral CST. While decreased anisotropy of the CST around the superior limiting sulcus and increased axial diffusivity of the CST near the midbrain level were noted, there was no significant correlation between pre-operative diffusion metrics and post-operative motor strength. In comparison, we found significant correlations between the elongation of the affected CST in the preoperative scans and post-operative motor strength in short-term and long-term follow ups (p = 1.810 × 10-4 and p = 9.560 × 10-4, respectively). CONCLUSIONS: We found a significant correlation between CST shape measures and post-operative motor function outcomes in patients with incidental insular LGGs. CST morphology shows promise as a potential prognostic factor for identifying functional deficits in this patient population.

Spatial distribution of supratentorial diffuse gliomas: A retrospective study of 990 cases.

Background: Gliomas distribute unevenly in the supratentorial brain space. Many factors were linked to tumor locations. This study aims to describe a more detailed distributing pattern of these tumors with age and pathological factors concerned. Methods: A consecutive series of 990 adult patients with newly-diagnosed supratentorial diffuse gliomas who underwent resection in Beijing Tiantan Hospital between January 2013 and January 2017 were retrospectively reviewed. For each patient, the anatomic locations were identified by the preoperative MRI, and the pathological subtypes were reviewed for histological grade and molecular status (if any) from his medical record. The MNI template was manually segmented to measure each anatomic location's volume, and its invaded ratio was then adjusted by the volume to calculate the frequency density. Factors of age and pathological subtypes were also compared among locations. Results: The insulae, hippocampi, and corpus callosum were locations of the densest frequencies. The frequency density decreased from the anterior to posterior (frontal - motor region - sensory region - parietal - occipital), while the grade (p < 0.0001) and the proportion of IDH-wt (p < 0.0001) increased. More tumors invading the right basal ganglion were MGMT-mt (p = 0.0007), and more of those invading the left frontal were TERT-wt (p = 0.0256). Age varied among locations and pathological subtypes. Conclusions: This study demonstrated more detailed spatial disproportions of supratentorial gliomas. There are potential interactions among age, pathological subtypes, and tumor locations.

A nomogram model to predict the acute venous thromboembolism risk after surgery in patients with glioma.

INTRODUCTION: Postoperative venous thromboembolism (VTE) is a common complication for glioma patients, with an incidence rate of about 20 %. The purpose of this study was to explore the risk factors of acute VTE after glioma surgery, which may provide an essential reference for clinical guidance on the prevention of acute VTE. MATERIALS AND METHODS: A total of 435 patients who underwent glioma surgery from 2012 to 2021 were included in this study. Duplex ultrasonography was performed routinely 3-5 days after the surgery to define VTE. Univariate and multivariate logistic regression analyses were performed to explore the independent predictor of acute VTE after glioma surgery and use these selected risk factors to construct and validate a nomogram. RESULTS: Several risk factors for predicting acute VTE after glioma surgery were identified and used to build the nomogram: age, operation time, systemic immune-inflammation index (SII), hypertension, and diabetes mellitus. The area under the curve of the nomogram was 0.834, indicating good discrimination. Hosmer-Lemeshow of the calibration curve was 3.05 (P = 0.98), showing a high degree of agreement between the prediction and actual outcome. Decision curve analysis indicated that the nomogram model was helpful when the incidence of VTE was 5-80 %. CONCLUSIONS: A nomogram to predict acute VTE after glioma surgery was constructed and validated. Clinicians can use this predictive model to achieve risk assessment and take different treatment measures to prevent acute postoperative VTE and improve patients' quality of life effectively.

Incidence of ischemic complications and technical nuances of arteries preservation for insular gliomas resection.

Introduction: Insular gliomas have complex anatomy and microvascular supply that make resection difficult. Furthermore, resection of insular glioma is associated with a significant risk of postoperative ischemic complications. Thus, this study aimed to assess the incidence of ischemic complications related to insular glioma resection, determine its risk factors, and describe a single surgeon's experience of artery-preserving tumor resection. Methods: We enrolled 75 consecutive patients with insular gliomas who underwent transcortical tumor resection. Preoperative and postoperative demographic, clinical, radiological [including diffusion-weighted imaging (DWI)], intraoperative neurophysiological data, and functional outcomes were analyzed. Motor evoked potentials (MEPs) and radiological characteristics like the relationship between the proximal segment of the lateral lenticulostriate arteries (LLSAs) and the tumor, the flat inner edge sign (the inner edge of the insular glioma is well-defined) or obscure inner edge sign, the distance between the lesion and posterior limb of the internal capsule and the invasion of the superior limiting sulcus by the tumor were analyzed. Strategies such as "residual triangle," "basal ganglia outline reappearance," and "sculpting" technique were used to preserve the LLSAs and the main branches of M2 for maximal tumor resection according to the Berger-Sinai classification. Results: Postoperative DWI showed acute ischemia in 44 patients (58.7%). Moreover, nine patients (12%) had developed new motor deficits, as determined by the treating neurosurgeons. The flat inner edge sign [odds ratio (OR), 0.144; 95% confidence interval (CI), 0.024-0.876) and MEPs (>50%) (OR, 18.182; 95% CI, 3.311-100.00) were significantly associated with postoperative core ischemia, which affected the posterior limb of the internal capsule or corona radiata. Conclusions: Insular glioma resection was associated with a high incidence of ischemia, as detected by DWI, as well as new motor deficits that were determined by the treating neurosurgeons. Insular glioma patients with obscure inner edge signs and intraoperative MEPs decline >50% had a higher risk of developing core ischemia. With our strategies, maximal safe resection of insular gliomas may be achieved.

Reduced sensitivity to delayed time and delayed reward of the post-operative insular glioma patients in delay discounting.

Previous studies have shown that the insula is closely related to addiction, and the structure's role in delay discounting can be measured by a specific task, but the specific role of the insula has been less studied. In this study, we first conducted a lesion study in which we recruited healthy controls (n = 30) and patients with unilateral insula injury (n = 16) to complete a behavioral delay discounting task. Then we conducted a functional magnetic resonance imaging (fMRI) study, and a separate group healthy volunteers (n = 51) completed a delay discounting task during the fMRI scan. The lesion study showed a significant difference between the two groups in the delay discounting task, which revealed that insula injury was associated with impaired decision making. The fMRI study revealed choice-sensitive insula activation that was modulated by delayed time and delayed reward, indicating an important role of the insula in delay discounting. Overall, our results provide evidence for a role of the insular lobe in delay discounting and suggests that this structure may be considered an important factor in the future treatment and diagnosis of addiction disorders.

Contralesional Structural Plasticity in Different Molecular Pathologic Subtypes of Insular Glioma.

Neuroplasticity may preserve neurologic function in insular glioma, thereby improving prognosis following resection. However, the anatomic and molecular bases of this phenomenon are not known. To address this gap in knowledge, the present study investigated contralesional compensation in different molecular pathologic subtypes of insular glioma by high-resolution three-dimensional T1-weighted structural magnetic resonance imaging. A total of 52 patients with insular glioma were examined. We compared the gray matter volume (GMV) of the contralesional insula according to histological grade [low-grade glioma (LGG) and high-grade glioma (HGG)] and molecular pathology status [isocitrate dehydrogenase (IDH) mutation, telomerase reverse-transcriptase (TERT) promoter mutation, and 1p19q codeletion] by voxel-based morphometry (VBM). A cluster of 320 voxels in contralesional insula with higher GMV was observed in glioma with IDH mutation as compared to IDH wild-type tumors by region of interest-based VBM analysis (family-wise error-corrected at p < 0.05). The GMV of the entire contralesional insula was also larger in insular glioma patients with IDH mutation than in patients with wild-type IDH. However, there was no association between histological grade, TERT promoter mutation, or 1p19q codeletion and GMV in the contralesional insula. Thus, IDH mutation is associated with greater structural compensation in insular glioma. These findings may be useful for predicting neurocognitive and functional outcomes in patients undergoing resection surgery.

Prediction of Lower Grade Insular Glioma Molecular Pathology Using Diffusion Tensor Imaging Metric-Based Histogram Parameters.

OBJECTIVES: To explore whether a simplified lesion delineation method and a set of diffusion tensor imaging (DTI) metric-based histogram parameters (mean, 25th percentile, 75th percentile, skewness, and kurtosis) are efficient at predicting the molecular pathology status (MGMT methylation, IDH mutation, TERT promoter mutation, and 1p19q codeletion) of lower grade insular gliomas (grades II and III). METHODS: 40 lower grade insular glioma patients in two medical centers underwent preoperative DTI scanning. For each patient, the entire abnormal area in their b-non (b0) image was defined as region of interest (ROI), and a set of histogram parameters were calculated for two DTI metrics, fractional anisotropy (FA) and mean diffusivity (MD). Then, we compared how these DTI metrics varied according to molecular pathology and glioma grade, with their predictive performance individually and jointly assessed using receiver operating characteristic curves. The reliability of the combined prediction was evaluated by the calibration curve and Hosmer and Lemeshow test. RESULTS: The mean, 25th percentile, and 75th percentile of FA were associated with glioma grade, while the mean, 25th percentile, 75th percentile, and skewness of both FA and MD predicted IDH mutation. The mean, 25th percentile, and 75th percentile of FA, and all MD histogram parameters significantly distinguished TERT promoter status. Similarly, all MD histogram parameters were associated with 1p19q status. However, none of the parameters analyzed for either metric successfully predicted MGMT methylation. The 25th percentile of FA yielded the highest prediction efficiency for glioma grade, IDH mutation, and TERT promoter mutation, while the 75th percentile of MD gave the best prediction of 1p19q codeletion. The combined prediction could enhance the discrimination of grading, IDH and TERT mutation, and also with a good fitness. CONCLUSIONS: Overall, more invasive gliomas showed higher FA and lower MD values. The simplified ROI delineation method presented here based on the combination of appropriate histogram parameters yielded a more practical and efficient approach to predicting molecular pathology in lower grade insular gliomas. This approach could help clinicians to determine the extent of tumor resection required and reduce complications, enabling more precise treatment of insular gliomas in combination with radiotherapy and chemotherapy.

Transcortical approach for insular gliomas: a series of 253 patients.

PURPOSE: The object of this study was to identify the distribution characteristics of insular gliomas and evaluate the efficiency of transcortical approach. METHODS: Insular gliomas patients who underwent transcortical approach for the first time between March 2011 and July 2019 at our institute were analyzed. RESULTS: A total of 253 primary insular gliomas patients were enrolled in the study. Of all patients, 176 patients (69.6%) underwent gross total resection, 61 patients (24.1%) underwent subtotal resection and 16 patients (6.3%) underwent partial resection. According to Berger-Sanai classification, the gross total resection rates of different types of insular gliomas were as follows: Zone I (90.1%), zone II (50.0%), zone III (40.0%), zone IV (89.5%), zone I + II (43.5%), zone I + IV (74.6%), zone II + III (44.4%), zone III + IV (41.7%), Giant (34.5%). According to our modified classification, the gross total resection rates were as follows: anterior type (84.9%), posterior type (45.8%), anterior-posterior type (42.9%), giant type (34.5%). After surgery, new limb motor deficit was observed in 28 patients (11.1%), and 5 patients (2.0%) were left long-term limb motor disability. New language impairment occurred in 23 patients (9.1%), and 3 patients (1.2%) were left long-term language disability. The patients were followed up for 1 to 89.2 months (average, 39.9 ± 20.3 months). At the end of follow-up, tumor progression occurred in 98 (38.7%) patients and 71 (28.1%) patients died of their disease. CONCLUSION: This study demonstrated that the maximal safe resection of insular gliomas can be achieved by transcortical approach. Insular gliomas had the characteristic of forward distribution, anterior transcortical approach can provide enough surgical freedom for anterior type of insular gliomas. If anterior tumors can make route to the posterior parts, anterior transcortical approach was also applied to some anterior-posterior and giant types of insular gliomas without resection of excessive brain, which may reduce the incidence of neurological complications.

Inadequate Expression and Activation of Mineralocorticoid Receptor Aggravates Spatial Memory Impairment after Traumatic Brain Injury.

The administration of glucocorticoids (GCs) for the treatment of traumatic brain injury (TBI) is controversial. Both protective and deleterious effects of GCs on the brain have been reported in previous studies, while the mechanisms are unclear. Most experimental studies have reported glucocorticoid receptor (GR)-mediated deleterious effects after TBI. Sufficient mineralocorticoid receptor (MR) activation was reported to be indispensable for normal function and survival of hippocampal neurons, but changes in MR expression and activation and the roles of MRs in the survival of neurons after TBI remain unclear. We hypothesized that inadequate MR expression and activation caused by TBI aggravates posttraumatic hippocampal apoptosis but that restoration by restoring MRs promotes the survival of neurons. Using a rat controlled cortical impact model, we examined plasma corticosterone, MR expression and activation, neuronal apoptosis in the hippocampus, and spatial memory on day 3 after injury with and without fludrocortisone (1 mg/kg) treatment. Plasma corticosterone levels were significantly reduced after TBI. In addition, both MR expression and activation were inhibited. Fludrocortisone treatment significantly increased both the expression and activation of MRs, reduced the number of apoptotic neurons and cell loss in the ipsilateral hippocampus, and subsequently improved spatial memory. Its protective effects were counteracted by the MR antagonist spironolactone. The results suggest that adequate expression and activation of MRs is crucial for the survival of neurons after TBI and that fludrocortisone protects hippocampal neurons via promoting MR expression and activation.

Eosinophils and other peripheral blood biomarkers in glioma grading: a preliminary study.

BACKGROUND: Many peripheral blood biomarkers are associated with glioma grade, but eosinophils (Eo) are scarcely reported. This study assessed preoperative peripheral eosinophil levels and other peripheral biomarkers presented in prior literature, probing their associations and diagnostic value in the grading of glioma, including its most aggressive type, glioblastoma (GBM). METHODS: Patients newly diagnosed with neuroepithelial tumors were included and divided into low-grade glioma (LGG)/high-grade glioma (HGG) groups and non-GBM/GBM groups separately. Preoperative peripheral biomarkers were collected, such as the counts of Eo, neutrophils (Neu), and lymphocytes (Ly), and values such as the eosinophil to lymphocyte ratio (ELR) and neutrophil to lymphocyte ratio (NLR) were calculated. Correlation analyses were also performed between these biomarkers and the groups. Receiver operating characteristic curves were utilized to assess the individual and joint diagnostic values of the biomarkers. RESULTS: The HGG patients presented lower Eo and ELR values, which had negative correlations with glioma grade. The diagnostic efficiency of Eo and ELR could be enhanced when combined other biomarkers. In the non-GBM vs GBM analysis, GBM patients displayed reduced Eo and a negative correlation between Eo and a GBM diagnosis The combination of Eo and other biomarkers enhanced the diagnostic efficiency. CONCLUSIONS: A negative correlation between peripheral eosinophils and glioma grade was found in our study. Numerous cytokines derived from eosinophils could regulate the immune response and affect the tumor microenvironment; moreover, eosinophils may inhibit the tumorigenesis of glioma, which should be explored in the future and may enlighten some new paths for glioma therapy.

Tanycytic ependymoma of filum terminale: Clinical characteristics and surgical outcomes.

Tanycytic ependymoma (TE), a rare subtype of ependymoma, was classified as grade II ependymoma by the World Health Organization in 2000 and 2007. Preoperative diagnosis of TE is challenging due to its similarities to schwannoma and astrocytoma; therefore, differentiation is required. The present study investigated the clinical, imaging and pathological characteristics of TE in the filum terminale. A retrospective analysis was conducted on the clinical, imaging, pathological and immunohistochemical characteristics of 8 patients with TE in the filum terminale and the relevant literature was reviewed. Of the 8 patients 7 were female and 1 was male, with an age range of 24-62 years old. The primary clinical symptom observed was lumbago, accompanied by lower limb pain and numbness. Magnetic resonance imaging predominantly identified isointensity on thoracic (T) 1-weighted images and iso- or hyperintense signal intensity on T2-weighted images, with homogeneous or inhomogeneous enhancement. All patients underwent resection of the tumor through a posterior median approach, and total resection was acighieved in 7 patients. During postoperative follow-up, all patients experienced improvement compared with their preoperative status, and were without tumor recurrence. The present study comprised the largest group of cases with TE in the filum terminale reported so far, to the best of our knowledge, which could foster a better understanding of this disease. Complete surgical resection of the tumor has the greatest effectiveness of any treatment for TE in the filum terminale. Postoperative histological examination, immunohistochemistry and electron microscopy for tumor specimens may assist in its diagnosis and differential diagnosis.

Decompressive craniectomy protects against hippocampal edema and behavioral deficits at an early stage of a moderately controlled cortical impact brain injury model in adult male rats.

A decompressive craniectomy (DC) has been shown to be a life-saving therapeutic treatment for traumatic brain injury (TBI) patients, which also might result in post-operative behavioral dysfunction. However, there is still no definite conclusion about whether the behavioral dysfunction already existed at an early stage after the DC operation or is just a long-term post-operation complication. Therefore, the aim of the present study was to analyze whether DC treatment was beneficial to behavioral function at an early stage post TBI. In this study, we established a controlled cortical impact injury rat model to evaluate the therapeutic effect of DC treatment on behavioral deficits at 1 d, 2 d, 3 d and 7 d after TBI. Our results showed that rats suffered significant behavioral and mood deficits after TBI compared to the control group, while decompressive craniectomy treatment could normalize MMP-9 expression levels and reduce hippocampal edema formation, stabilize the expression of Synapsin I, which was a potential indicator of maintaining the hippocampal synaptic function, thus counteracting behavioral but not mood decay in rats subjected to TBI. In conclusion, decompressive craniectomy, excepting for its life-saving effect, could also play a potential beneficial neuroprotective role on behavioral but not mood deficits at an early stage of moderate traumatic brain injury in rats.

Quantitative Assessment of Invasion of High-Grade Gliomas Using Diffusion Tensor Magnetic Resonance Imaging.

OBJECTIVE: To determine heterogeneity of high-grade glioma (HGG) and its surrounding area and explore quantitative analysis of invasion of HGG using diffusion tensor imaging. METHODS: This study included 14 patients with HGG and preoperative magnetic resonance imaging and diffusion tensor imaging examinations. Three regions of interest were placed. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values of these regions of interest were measured, and specimens from the 3 regions of interest were obtained under navigation guidance. Postoperative examinations of specimens were carried out. Correlations between ADC and FA values and tumor cell density were evaluated. RESULTS: Median survival was 36.7 months. As distance from the tumor increased, the number of tumor cells significantly decreased. Regarding levels of matrix metalloproteinase-9 and Ki-67, only the differences between tumor and distances of 1 cm and 2 cm away from the tumor were statistically significant. For analysis of the relationship between tumor cell density and ADC and FA values, the discriminant formulas were as follows: G1 = -13.678 + 14984.791 (X) + 14443.847 (Y) (tumor cell density ≥10%); G2 = -11.649 + 14443.847 (X) + 33.285 (Y) (tumor cell density <10%). CONCLUSIONS: We verified the heterogeneity of HGG and its surrounding area and found that patients with extensive resection may have longer survival. We also found a few formulas using FA and ADC values to predict tumor cell density.

Clinical Features, Treatment, and Prognostic Factors of 56 Intracranial and Intraspinal Clear Cell Meningiomas.

OBJECTIVE: Intracranial and intraspinal clear cell meningiomas (CCMs) are rarely reported because of their extremely low incidence, and the current understanding of CCM is poor. The purpose of this study was to analyze the incidence and the clinical, radiologic, pathologic, and prognostic features of intracranial and intraspinal CCMs. METHODS: Among 14,310 cases of intracranial and intraspinal meningiomas that were surgically treated between 2006 and 2016 at Beijing Tian Tan Hospital, 56 were chosen for analysis and retrospectively reviewed. To determine which parameters were associated with longer progression-free survival (PFS) and overall survival (OS), statistical analysis was performed. RESULTS: CCMs accounted for approximately 0.39% of all intracranial and intraspinal meningiomas. Patients with CCM had a mean age of 32.3 years and there was a female predilection (20 males and 36 females). Gross total resection was achieved in 35 cases, and subtotal resection was achieved in 21 cases. All patients were followed up for 10-206 months after surgery. Twenty-six patients experienced tumor recurrence, and the median PFS was 48.0 months. The 1-year, 3-year, and 5-year PFS was 87.5%, 59.8%, and 41.8%, respectively. Twelve patients died of tumor recurrence, and the median OS was not available. The 1-year, 3-year, and 5-year OS was 98.2%, 91.3%, and 65.8%, respectively. Univariate analysis showed that total tumor removal was significantly associated with a better prognosis. Multivariate analysis confirmed only Simpson grade III and IV resection as an independent risk factor for shorter PFS. Radiotherapy mildly improved PFS after both gross total resection and subtotal resection, showing no significant difference because of the small sample size and short follow-up duration. CONCLUSIONS: CCM is a rare subtype of World Health Organization grade II meningioma. CCM typically involves young patients and shows a female predilection and high recurrence rate. When possible, total resection is the primary and most suitable treatment for CCM. For patients with primary tumors, radiotherapy is recommended after the initial operation regardless of the extent of resection. For patients with disease recurrence, secondary surgery combined with radiotherapy might serve as an effective treatment.

Clinical features, surgical management, and prognostic factors of secretory meningiomas: a single-center case series of 149 patients.

Secretory meningioma (SM) is a rare histological subtype of the meningioma family. Few reports investigating SM have been published due to its extremely low incidence; thus, the current understanding of this disease is poor. We analyzed the incidence and clinical, radiological, pathological, and prognostic features of SM. Approximately 12,380 intracranial meningiomas were surgically resected at Beijing Tiantan Hospital between April 2008 and January 2017. All pathologically confirmed SM cases were identified. SMs accounted for approximately 1.2% of the intracranial meningiomas (149 of 12,380). The patients with SM had a mean age of 51.0 years and were predominantly female (112 female and 37 male). Radiologically, peritumoral brain edema was observed in 49 (32.9%) patients. Gross total resection was achieved in 115 (77.2%) cases. At the 35-months median follow-up (range 4-109 months), six patients had tumor recurrence, and one patient died from the tumor recurrence. The 5-year progression-free survival rates were 95.9%, and the 5-year overall survival rate was 99.3%. A skull base location and a tumor size ≥ 3.5 cm were significantly associated with poor short-term outcomes, and a skull base location was significantly associated with an increased risk of poor long-term outcomes (P < 0.05). A skull base location (OR 3.797; 95% CI 1.071-13.468; P = 0.039) and tumor size ≥ 3.5 cm (OR 2.616; 95% CI 1.107-6.181; P = 0.028) were independent risk factors for non-gross total resection. A son-skull base location (OR 0.070; 95% CI 0.028-0.177; P = 0.001) was the only independent risk factor that correlated with more severe peritumoral brain edema. SM is a rare subtype of meningiomas with a female predominance and low recurrence. Our results highlight the risk factors for short- and long-term outcomes, which can be useful for selecting treatments and predicting prognosis. Microsurgical treatment of a skull base SM remains a formidable challenge due to a large tumor size and critical neurovascular structure encasement.