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.

Preparation of well-distributed titania nanopillar arrays on Ti6Al4V surface by induction heating for enhancing osteogenic differentiation of stem cells.

Great effort has recently been devoted to the preparation of nanoscale surfaces on titanium-based implants to achieve clinically fast osteoinduction and osseointegration, which relies on the unique characteristics of the nanostructure. In this work, we used induction heating treatment (IHT) as a rapid oxidation method to fabricate a porous nanoscale oxide layer on the Ti6Al4V surface for better medical application. Well-distributed vertical nanopillars were yielded by IHT for 20-35 s on the alloy surface. The composition of the oxides contained rutile/anatase TiO2 and a small amount of Al2O3 between the TiO2 grain boundaries (GBs). This technology resulted in a reduction and subsequent increase of surface roughness of 26-32 nm when upregulating the heating time, followed by the successive enhancement of the thickness, wettability and adhesion strength of the oxidation layer to the matrix. The surface hardness also distinctly rose to 554 HV in the IHT-35 s group compared with the 350 HV of bare Ti6Al4V. The massive small-angle GBs in the bare alloy promoted the formation of nanosized oxide crystallites. The grain refinement and deformation texture reduction further improved the mechanical properties of the matrix after IHT. Moreover, in vitro experiments on a mesenchymal stem cell (BMSC) culture derived from human bone marrow for 1-7 days indicated that the nanoscale layers did not cause cytotoxicity, and facilitated cell differentiation in osteoblasts by enhancing the gene and osteogenesis-related protein expressions after 1-3 weeks of culturing. The increase of the IHT time slightly advanced the BMSC proliferation and differentiation, especially during long-term culture. Our findings provide strong evidence that IHT oxidation technology is a novel nanosurface modification technology, which is potentially promising for further clinical development.

"Dynamic spot sign" on CT perfusion source images predicts haematoma expansion in acute intracerebral haemorrhage.

OBJECTIVES: To evaluate the association between dynamic progressive enhancing foci ("dynamic spot sign") in acute haematoma on CT perfusion source images (CTP-SI) and haematoma expansion. METHODS: One hundred twelve consecutive patients with spontaneous intracerebral haemorrhage according to unenhanced CT, CTP and CT angiography within 6 h of symptom onset were prospectively evaluated. Patients were dichotomised according to the presence/absence of the dynamic spot sign on CTP-SI in haematoma. The predictive value of haematoma expansion was analysed. RESULTS: Haematoma expansion was detected in 28 patients (25.0 %) on follow-up unenhanced CT images. Thirty patients (26.8 %) demonstrated the dynamic spot sign on CTP-SI, about 83.3 % of patients with haematoma expansion (P < 0.001). Sensitivity, specificity, positive predictive value, negative predictive value and kappa value for expansion were 89.3 %, 94.0 %, 96.3 %, 83.3 % and 0.814, respectively. In multiple regression, the presence of the CTP dynamic spot sign within acute haematomas independently predicted haematoma expansion; the univariate analysis OR value was 131.667 (29.386-590.289), P < 0.0001. Moreover, the multivariate analysis CTP dynamic spot sign OR value was 203.996 (32.123-1295.488), P < 0.0001. CONCLUSIONS: The CTP-SI dynamic spot sign is associated with acute haematoma expansion, is more direct in showing active ongoing bleeding and has a higher predictive value than the CTA spot sign. KEY POINTS: • It is important to identify potential progression of spontaneous intracerebral haemorrhage. • Dynamic enhancement within CT perfusion source images is associated with haemorrhage expansion. • The CTP dynamic spot sign may be present throughout arterial to venous phase imaging. • The CTP dynamic spot sign carries a higher predive value for haematoma expansion than CTA.

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.

Clinical characteristics associated with the intracranial dissemination of gliomas.

OBJECTIVES: Glioma is the most common malignant tumor of the brain and the intracranial dissemination of gliomas is the late stage of the development of the tumor. However, there is little research in literature on the occurrence of intracranial dissemination of gliomas. In order to provide a reference for clinical work, we carried out this study on intracranial dissemination of glioma. PATIENTS AND METHODS: A total of 629 patients with gliomas received tumor resection by the same surgeon from August 2010 to September 2015 were included in this study. The authors performed a retrospective review of the patients and the information regarding clinical features, histopathological results, molecular pathologic results and clinical outcomes was collected and analyzed. RESULTS: In this retrospective study, we found that the intracranial dissemination phenomenon occurred in 53 patients (8.43%). We analyzed the clinical characteristics of patients and found that the age at diagnosis (P = 0.011), WHO grade of the tumor (P < 0.001), and involvement of the corpus callosum (P = 0.010) were associated with the occurrence of dissemination. The higher grade of the tumor, the more prone to disseminate. Deletion of 1p/19q had no significant correlation with the intracranial dissemination. MMP9, Ki-67, and EGFR were highly expressed in tumor cells that caused dissemination, and the level of Ki-67 expression had significance in statistics (P < 0.01). CONCLUSION: In our study, older age (>40 years), high pathological grade, invasion of the corpus callosum and high levels of Ki-67 expression were risk factors associated with the intracranial dissemination of gliomas.

[Research about the mechanism in masticatory muscle dysfunctional induced by hemimastication].

OBJECTIVE: To study the mechanism in masticatory muscle dysfunctional induced by hemimastication. METHODS: Ca2+ contents were measured with atomic absorption spectrometry; calcinuerin were measured with colorimetric method; muscle fiber types were measured with adenosine-triphosphate (ATPase) staining. RESULTS: (1) Compared with the controls, Ca2+ contents in experimental group had the higher level except 8 weeks (P < 0.05). (2) The ratio of slow fiber in experimental group increased, higher than the match groups (P < 0.05). (3) With Ca2 contents rise, the activities of calcinuerin present a bell-like shape. (4) The ratio of slow-type fiber was positively correlated to the activities of calcinuerin (r = 0.876, P < 0.05). CONCLUSION: The signal way of muscle fiber growth and fiber transformation were activated by high concentration of calcium, then, muscle fiber transferred from fast to slow type. It may play an important role in the mechanism that hemimastication result in masticatory muscles dysfunction.

[A preliminary study on the effects of the exogenous creatine phosphate on rat masseter muscle after unilateral chew].

OBJECTIVE: To study the effect of energy therapy on Ca2+ concentration and Ca2+ -ATP enzyme activity in rat master muscle after unilateral chew, and to discuss the protective action of the exogenous creatine phosphate on rat masseter muscle after unilateral chew. METHODS: The 20 rats were randomly divided into 4 groups, A: Creatine phosphate normal control group; B: Creatine phosphate experimental group; C: Saline normal control group; D: Saline experimental group. The Ca2+ concentration were determined by atomic absorption spectrophotometry, the activity of the Ca2+ -ATP enzyme were determined by super-micro volume Ca2+ -ATP enzyme kit. RESULTS: (1) The Ca2+ concentration of the extraction side of group D which received the saline injection had significant difference compared with the non-extraction side (P = 0.007), the group C (P = 0.009) and the extraction side of group B (P = 0.01); (2) Ca2+ -ATP enzyme activity of group D were higher than its non-extraction side (P = 0.001), group C (P = 0.003) and the extraction side of group B (P = 0.001); (3) The ultrastructural changes of the rat masseter muscle under transmission electron microscope were as follows: The extraction side of group D have more severe pathological manifestations than non-extraction side. Both the extraction side and the non-extraction side of group B had a similar manifestation to the normal control group. CONCLUSION: Exogenous energy material, creatine phosphate, may have certain degree of protective effect on rat masseter muscles after unilateral chew. And it may become a possible way to improve the injury of the masseter muscle.