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Background: Current radiomics for treatment response assessment in gastric cancer (GC) have focused solely on Computed tomography (CT). The importance of multi‐parametric magnetic resonance imaging (mp‐MRI) radiomics in GC is less clear. Purpose: To compare and combine CT and mp‐MRI radiomics for pretreatment identification of pathological response to neoadjuvant chemotherapy in GC. Study Type: Retrospective. Population: Two hundred twenty‐five GC patients were recruited and split into training (157) and validation dataset (68) in the ratio of 7:3 randomly. Field/Sequence: T2‐weighted fast spin echo (fat suppressed T2‐weighted imaging [fs‐T2WI]), diffusion weighted echo planar imaging (DWI), and fast gradient echo (dynamic contrast enhanced [DCE]) sequences at 3.0T. Assessment: Apparent diffusion coefficient (ADC) maps were generated from DWI. CT, fs‐T2WI, ADC, DCE, and mp‐MRI Radiomics score (Radscores) were compared between responders and non‐responders. A multimodal nomogram combining CT and mp‐MRI Radscores was developed. Patients were followed up for 3–65 months (median 19) after surgery, the overall survival (OS) and progression free survival (PFS) were calculated. Statistical Tests: A logistic regression classifier was applied to construct the five models. Each model's performance was evaluated using a receiver operating characteristic curve. The association of the nomogram with OS/PFS was evaluated by Kaplan–Meier survival analysis and C‐index. A P value <0.05 was considered statistically significant. Results: CT Radscore, mp‐MRI Radscore and nomogram were significantly associated with tumor regression grading. The nomogram achieved the highest area under the curves (AUCs) of 0.893 (0.834–0.937) and 0.871 (0.767–0.940) in training and validation datasets, respectively. The C‐index was 0.589 for OS and 0.601 for PFS. The AUCs of the mp‐MRI model were not significantly different to that of the CT model in training (0.831 vs. 0.770, P = 0.267) and validation dataset (0.797 vs. 0.746, P = 0.137). Data Conclusions: mp‐MRI radiomics provides similar results to CT radiomics for early identification of pathologic response to neoadjuvant chemotherapy. The multimodal radiomics nomogram further improved the capability. Evidence Level: 3 Technical Efficacy: 2 [ABSTRACT FROM AUTHOR]

Objective: The objective of our study was to retrospectively evaluate the efficacy of combined analysis of T2-weighted imaging and DWI in the diagnosis of parametrial invasion (PMI) in cervical carcinoma., Materials and Methods: The clinical records of 192 patients with cervical carcinoma who met the study requirements were reviewed for this retrospective study. The signal intensities of suspicious PMI tissue were assessed on T2-weighted images, DW images, and apparent diffusion coefficient maps independently by two experienced radiologists. The radiologist observers predicted the presence of PMI by scoring T2-weighted imaging alone and then by scoring T2-weighted imaging and DWI combined. The results were compared with histopathologic findings., Results: Histopathologic findings revealed PMI in 24 of 192 study subjects. In positively predicting the presence of PMI, T2-weighted imaging and DWI combined scored significantly better than T2-weighted imaging alone, as proven by high sensitivity (T2-weighted imaging alone vs T2-weighted imaging and DWI combined: observer 1, 75.0% vs 83.3% [p = 0.477]; observer 2, 66.7% vs 91.7% [p < 0.05]), high specificity (T2-weighted imaging alone vs T2-weighted imaging and DWI combined: observer 1, 84.5% vs 98.8% [p < 0.001]; observer 2, 85.7% vs 98.8% [p < 0.001]), and high accuracy (T2-weighted imaging alone vs T2-weighted imaging and DWI combined: observer 1, 83.3% vs 96.9% [p < 0.001]; observer 2, 83.3% vs 97.9% [p < 0.001]). The area under the ROC curve was also significantly higher for T2-weighted imaging and DWI combined (observer 1, 0.911; observer 2, 0.952) than for T2-weighted imaging alone (observer 1, 0.798; observer 2, 0.762). Although the interobserver agreement was good for T2-weighted imaging (κ = 0.695) and excellent for T2-weighted imaging and DWI combined (κ = 0.753), the improvement failed to achieve statistical significance (p = 0.28)., Conclusion: Combined analysis of T2-weighted imaging and DWI enhances the accuracy of diagnosing PMI in patients with cervical cancer compared with T2-weighted imaging alone.

Background: Reliable early prediction response to therapy and time-to-progression (TTP) remain an important goal of high-grade gliomas (HGGs) research. Proton magnetic resonance spectroscopy ((1)H-MRS) has been applied with variable success in clinical application, and we hypothesize that (1)H-MRS in predictive value should perform well as a marker of TTP in patients treated with radiotherapy (RT) after surgery., Methods: (1)H-MRS was performed before surgery on 25 patients who had undergone resection of HGGs; then the ratios of lipid/creatine (Lip/Cr) and myo-inositol/creatine (mI/Cr) were determined in the solid tumor. RT response was classified as follows: complete resolution (CR), partial response (PR), stable disease (SD), and progressive disease (PD) by comparison of pre-treatment and post-radiotherapy scans. TTP was defined at the time to radiographic progression by MacDonald criteria. Correlation was evaluated between the ratios of Lip/Cr, mI/Cr and treatment response, TTP. The chi-square test and Pearson correlation test were used for data analyses., Results: Multivariate analysis revealed that the prognostic value of spectroscopic variables was independent of age, sex, WHO histologic grade, extent of surgery, and Karnofsky score (KPS). The correlation between the ratios of lipid/Cr and TTP was significant (r = 0.894, P = 0.000), and between the ratios of mI/Cr and TTP was also significant (r = 0.891, P = 0.000). As predicted, RT response correlated significantly with TTP (r = 0.59, P = 0.002): median TTP was 49.9 days for patients with PD compared with 202.7 days for SD, 208.0 days for PR, and 234.5 days for CR., Conclusion: The ratios of Lip/Cr and mI/Cr of the solid tumor region before surgery could provide important information in predicting RT response and TTP in patients with HGGs treated by radiation alone after surgery.

Objective: To locate motor functional area of patients who undergone modified anatomical hemispherectomy in order to analysis the plasticity of upper limbs motor., Methods: The patients who undergone modified anatomical hemispherectomy were performed BOLD sequences, to locate functional cortical areas in their residual brain., Results: 6 patients have performed examination of BOLD sequences by 3.0-T MRI.5 of them obtained contralateral upper limb motor areas in their residual brain, and 3 of them obtained ipsilateral and contralateral upper limb motor area map in cortex. The ipsilateral upper limb motor areas in the M1, SMA and posterior parietal cortex., Conclusions: The patients who undergone modified anatomical hemispherectomy is an excellent model to investigate mechanism of plasticity in the developing brain. Functional magnetic resonance (fMRI) provided fine spatial detail of brain responses, would describe the motor functional area of cortical maps. These patients exist ipsilateral motor areas in their residual mono hemisphere. The study indicated there maybe have somewhat extent of correlation between the surgical procedure and the outcome of neuroplasticity.

The surface-enhanced Raman scattering (SERS) spectra of adenine, purine and pyrene adsorbed on a SERS-active silver surface roughened by nitric acid have been measured over the -190 degrees C-30 degrees C surface temperature range. The results show that the Raman shifts and SERS intensity of the vibrations, which are enhanced by electromagnetic mechanism, are affected by temperature, those by chemical mechanism are not. However, it has been found that the observed temperature dependence can be explained by postulating the reorientation of the absorbates. Adenine molecules and purine molecules prefer to adopt a more perpendicular stance on the surface at high temperature, but for a planar symmetric molecule, such as pyrene, the preferred orientation is parallel and temperature has no effect on its orientation.