Statistics of metabolic ratios in different areas using AQoCE and Siemens approaches.

<p>Note: Data are expressed as mean±standard deviation.</p><p>Statistics of metabolic ratios in different areas using AQoCE and Siemens approaches.</p

Pathology data.

<p>Pathology data.</p

<i>t</i>-test of intratumoral metabolic ratios in AQoCE and Siemens approaches.

<p>Note: Data are <i>t</i>/<i>p</i> values of independent sample <i>t</i>-test.</p><p><i>t</i>-test of intratumoral metabolic ratios in AQoCE and Siemens approaches.</p

Statistics of intratumoral metabolic ratios by AQoCE and Siemens approaches.

<p>Note: Data are expressed as mean±standard deviation.</p><p>Statistics of intratumoral metabolic ratios by AQoCE and Siemens approaches.</p

Images of a 31-year-old female with a grade II astrocytoma.

<p>MRS grid map overlaid on a T2-weighted image (top left). T1-weighted image (top right). Spectroscopy processed by the AQoCE approach (bottom left). Spectroscopy processed by Siemens processing software (bottom right). The chosen spectroscopy volume of interest (VOI) is located in the peritumoral area. Scale bar: 1 cm.</p

Convex-Envelope Based Automated Quantitative Approach to Multi-Voxel ¹H-MRS Applied to Brain Tumor Analysis

<div><p>Background</p><p>Magnetic Resonance Spectroscopy (MRS) can measure <i>in vivo</i> brain tissue metabolism that exhibits unique biochemical characteristics in brain tumors. For clinical application, an efficient and versatile quantification method of MRS would be an important tool for medical research, particularly for exploring the scientific problem of tumor monitoring. The objective of our study is to propose an automated MRS quantitative approach and assess the feasibility of this approach for glioma grading, prognosis and boundary detection.</p><p>Methods</p><p>An automated quantitative approach based on a convex envelope (AQoCE) is proposed in this paper, including preprocessing, convex-envelope based baseline fitting, bias correction, sectional baseline removal, and peak detection, in a total of 5 steps. Some metabolic ratios acquired by this quantification are selected for statistical analysis. An independent sample t-test and the Kruskal-Wallis test are used for distinguishing low-grade gliomas (LGG) and high-grade gliomas (HGG) and for detecting the tumor, peritumoral and contralateral areas, respectively. Seventy-eight cases of pre-operative brain gliomas with pathological reports are included in this study.</p><p>Results</p><p>Cho/NAA, Cho/Cr and Lip-Lac/Cr (LL/Cr) calculated by AQoCE in the tumor area differ significantly between LGG and HGG, with <i>p</i>≤0.005. Using logistic regression combining Cho/NAA, Cho/Cr and LL/Cr to generate a ROC curve, AQoCE achieves a sensitivity of 92.9%, a specificity of 72.2%, and an area under ROC curve (AUC) of 0.860. Moreover, both Cho/NAA and Cho/Cr in the AQoCE approach show a significant difference (<i>p</i>≤0.019) between tumoral, peritumoral, and contralateral areas. The comparison between the results of AQoCE and Siemens MRS processing software are also discussed in this paper.</p><p>Conclusions</p><p>The AQoCE approach is an automated method of residual water removal and metabolite quantification. It can be applied to multi-voxel ¹H-MRS for evaluating brain glioma grading and demonstrating characteristics of brain glioma metabolism. It can also detect infiltration in the peritumoral area. Under the limited clinical data used, AQoCE is significantly more versatile and efficient compared to the reference approach of Siemens.</p></div

Kruskal-Wallis test of metabolic ratios in different areas using AQoCE and Siemens approaches.

<p>Note: Data are <i>h</i>/<i>p</i> values of the Kruskal-Wallis test.</p><p>Kruskal-Wallis test of metabolic ratios in different areas using AQoCE and Siemens approaches.</p

Samples of spectroscopy processed by Siemens processing software with LL quantification error.

<p>All the chosen spectroscopies belong to tumoral area. The quantification results are presented in red line, and these errors should be found at the location of Lac point by comparing with original spectrum (white line).</p

Significance of miR-196b in Tumor-Related Epilepsy of Patients with Gliomas

<div><h3>Objectives</h3><p>Seizure is a common presenting symptom of primary brain tumors. There are no published studies regarding the roles of MicroRNA (miRNA) in tumor-related epilepsy. The authors set out to correlate miR-196b expression in low-grade glioma patients with pre-operative seizures and post-operative seizure control.</p> <h3>Methods</h3><p>Twenty-three patients with WHO grade II astrocytomas and 83 similar patients for independent validation were included. Follow-up visits regarding seizure prognosis were scheduled at 6 months. MiRNA profiling was used to identify differentially expressed miRNAs. The most important miRNA was determined by quantitative reverse-transcriptase polymerase chain reaction (q-PCR) in the validation cohort. Gene ontology (GO) analysis and whole genome mRNA profiling was performed to investigate the underlying biological processes.</p> <h3>Results</h3><p>Array results showed that 30 miRNAs were overexpressed and 10 miRNAs were underexpressed (with more than 2 fold change) in patients with pre-operative seizures. MiR-196b was validated in the independent validation cohort. Patients with good seizure prognosis exhibited low levels of miR-196b expression compared with those who had poor seizure prognosis in the group without pre-operative seizures. Biological processes that relate to transcription and cell cycles were over-represented in the miR-196b-associated gene expression signature. MiR-196b-associated gene expression profiling was characterized by enrichment of genes usually involved in cell proliferation.</p> <h3>Conclusions</h3><p>We have provided the first evidence that expression of miR-196b was associated with the occurrence of pre-operative seizures in low-grade gliomas, and may predict seizure prognosis in patients without pre-operative seizures. Targeted treatments that decrease endogenous levels of miR-196b might represent novel therapeutic strategies.</p> </div

Association of miR-196b expression by qPCR with the occurrence of pre-operative seizures in LGGs.

<p>(A) Patients with pre-operative seizures exhibited higher expression levels of miR-196b when compared with those without pre-operative seizures. (B) The diagnostic role of miR-196b for determining the occurrence of pre-operative seizures using receiver operating characteristic curve analysis.</p