Value of dual-layer detector spectral CT quantitative parameters in evaluating treatment response of neoadjuvant chemoradiotherapy in patients with locally advanced rectal cancer / 中华放射学杂志

Objective:To explore the value of dual-layer detector spectral CT quantitative parameters in evaluating the treatment response of neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced rectal cancer (LARC).Methods:The study was a cross-sectional study. From May 2021 to March 2023, a total of 52 patients with LARC who received complete nCRT and were pathologically confirmed rectal adenocarcinoma at the Guangdong Province Hospital of Traditional Chinese Medicine were retrospectively enrolled. Each patient underwent spectral CT examination before and after nCRT, including plain scan, arterial phase (AP), and venous phase (VP) scans. According to the tumor regression grade, the patients were divided into the good response ( n=20) and the poor response group ( n=32). Measurements of the primary tumor′s spectral CT parameters, including effective atomic number (Z eff) at plain scan, iodine concentration (IC), CT values of 40 keV and 100 keV virtual monochromatic image (VMI) at dual-enhanced phases, were taken before and after nCRT. Additionally, the normalized iodine concentration (NIC), spectral curve slope (λHU), and the change rate of the above parameters before and after nCRT were calculated. The independent sample t-test or Mann-Whitney U test was used to compare the differences between the two groups. The receiver operating characteristic (ROC) curve was used to assess the efficacy of various metrics in evaluating the tumor treatment response of nCRT. A binary logistic regression analysis of combined parameter results was performed for the parameters with the areas under curve (AUC)>0.75, and the AUC of the combined parameter was evaluated. Results:There were significant differences in NIC AP and λHU VP before nCRT, NIC VP and λHU VP after nCRT, and the change rates of Z eff, NIC AP, NIC VP and λHU AP between the good response group and the poor response group ( P<0.05). The remaining parameters showed no statistically significant difference ( P>0.05). The ROC curve results showed that the AUCs of the above 8 parameters for evaluating tumor treatment response of nCRT were 0.702, 0.655, 0.695, 0.769, 0.738, 0.807, 0.791, and 0.677, respectively. The AUC of the combined model of the three parameters with AUC>0.75 (λHU VP after nCRT, the change rate of NIC AP and NIC VP) was 0.869, with 80.0% sensitivity and 84.4% specificity. Conclusion:The quantitative parameters derived from spectral CT may provide new markers for evaluating the response to nCRT treatment in patients with LARC. The multi-parameter combined model can improve diagnostic efficacy.

Prediction of 1p/19q codeletion status in diffuse lower-grade glioma using multimodal MRI radiomics / 南方医科大学学报

OBJECTIVE@#To develop a noninvasive method for prediction of 1p/19q codeletion in diffuse lower-grade glioma (DLGG) based on multimodal magnetic resonance imaging (MRI) radiomics.@*METHODS@#We collected MRI data from 104 patients with pathologically confirmed DLGG between October, 2015 and September, 2022. A total of 535 radiomics features were extracted from T2WI, T1WI, FLAIR, CE-T1WI and DWI, including 70 morphological features, 90 first order features, and 375 texture features. We constructed logistic regression (LR), logistic regression least absolute shrinkage and selection operator (LRlasso), support vector machine (SVM) and Linear Discriminant Analysis (LDA) radiomics models and compared their predictive performance after 10-fold cross validation. The MRI images were reviewed by two radiologists independently for predicting the 1p/19q status. Receiver operating characteristic curves were used to evaluate classification performance of the radiomics models and the radiologists.@*RESULTS@#The 4 radiomics models (LR, LRlasso, SVM and LDA) achieved similar area under the curve (AUC) in the validation dataset (0.833, 0.819, 0.824 and 0.819, respectively; P>0.1), and their predictive performance was all superior to that of resident physicians of radiology (AUC=0.645, P=0.011, 0.022, 0.016, 0.030, respectively) and similar to that of attending physicians of radiology (AUC=0.838, P>0.05).@*CONCLUSION@#Multiparametric MRI radiomics models show good performance for noninvasive prediction of 1p/19q codeletion status in patients with in diffuse lower-grade glioma.

The value of wholeGtumor texture analysis of contrastGenhanced T1 WI in differentiating cystic glioma from brain abscess / 实用放射学杂志

Objective To evaluate the feasibility of wholeGtumor texture analysis of contrastGenhanced T1 WI (T1 Ce)in differentiating cystic glioma (CG)from brain abscess (BA).Methods MRI data of 25 cases of ringGenhanced CG and 24 cases of BA proven pathologically were retrospectively studied.All the patients underwent preGsurgery MRI plain and contrastGenhanced scans.FireVoxel software was used to outline the ROI of the wholeGtumor.The signal intensity histogram and related texture parameters of the 3D ROI were obtained,including mean, median,standard deviation,inhomogeneity,skewness,kurtosis and entropy.The data were first tested for normality and the differences in wholeG tumor texture analysis parameters of T1 Ce between CGs and BAs were compared using the independentGsample t test(normal distribution)and MannGWhitney rank sum test (skewed distribution).ROC curve was used to evaluate the efficacy of the parameter in differentiating CG from BA.Results There were statistical significances in the parameters of mean,median,standard deviation,inhomogeneity and skewness between CGs and BAs(P＜0.05),and there were no any statistical significances in kurtosis and entropy between CGs and BAs(P＞0.05).In all the texture parameters,the AUC of inhomogeneity was the largest(0.988),and when the threshold was 0.314, the sensitivity and the specificity were 92.60% and 9 7.1 0%,respectively.Conclusion Some of the quantitative parameters of the wholeGtumor texture analysis of T1 Ce(mean,median,standard deviation,inhomogeneity and skewness)could provide reliable and objective evidences for imaging differential diagnosis of CG and BA preGsurgery.

Abnormal resting brain activity of default mode network in patients with gastroesophageal reflux disease / 中华神经医学杂志

Objective To compare the default mode network (DMN) between patients with gastroesophageal reflux disease (GERD) and healthy controls (HCs).Methods Included for this study were 30 GERD patients who were treated at Department of Digestive Diseases,Zhujiang Hospital from September 2016 to December 2017 and contemporary 49 HCs who received health examination at the out-patient department.Resting-state functional magnetic resonance imaging (fMRI) was conducted for the 2 groups.Fractional amplitude of low-frequency fluctuation (fALFF) and regional homogeneity (ReHo) were used to study significant alterations in their DMN.Results Compared with the HCs,the GERD patients demonstrated the following alterations:the ReHo values were significantly decreased in bilateral superior temporal gyri,middle temporal gyri and dorsal anterior cingulate cortexes (dACC) but significantly increased in bilateral medial prefrontal lobes,dorsal anterior cingutates,posterior cingulates,precunei,and angular gyri;the fALFF value was increased in bilateral dACC and precunei but decreased in the paracentral lobules (P＜0.05).Conjunction analyses using both ReHo and fALFF values of their DMN showed the overlapping activated brain regions lied in the paracentral lobules,dACC and precunei.The fALFF values in the paracentral lobules and the dACC of the GERD patients were negatively correlated with their disease course (r=-0.380,P=0.035;r=-0.375,P=0.041) while the ReHo values in the superior temporal gyri of the GERD patients were also negatively correlated with their disease course (r=-0.446,P=0.016).Conclusion In GERD patients,their DMN might undergo dysfunctional changes because of the abnormal activity of DMN which may be correlated with their disorder of visceral sensation.

Comparative study of clinical and MRI features between intracranial solitary fibrous tumor/hemangiopericytoma and meningioma / 中国医学影像技术

Objective To investigate the MRI features of intracranial solitary fibrous tumors/hemangiopericytomas (SFT/HPC),and to compare these findings with those of intracranial meningiomas.Methods The clinical features and MRI findings in 28 patients of intracranial SFT/HPC (SFT/HPC group)and 68 patients of meningiomas (meningiomas group) confirmed by operation and pathology were retrospectively analyzed.The indicators of two groups were compared.Results Shape of tumor,signal homogeneous,signal voids of vessel in tumor,hypointense signal nodules on T2WI and enhanded,cystic or necrosis in tumor,meningeal tail sign,changes of the nearby bone,sex,Ki-67％ level,blood lose in surgery had significant differences between SFT/HPC group and meningiomas group (all P＜0.05).Conclusion There are some differences between intracranial SFT/HPC and meningiomas.It is helpful in diagnosis and differential diagnosis through the comparative analysis of the imaging signs.

MR imaging features of intracranial tumors in infants: a report of 12 cases / 中华神经医学杂志

Objective To explore the MR imaging characteristics of brain tumors in infants to improve the diagnosis and early treatment.Methods Twelve infants with brain tumors (less than 1 year old),performed surgery in our hospital from April 2008 to August 2014 and proved by pathology,were collected in our study; the clinical data and MR imaging features were reviewed retrospectively.Results Among the 12 infants,4 (33％) had tumors located at the lateral ventricle,3 (25％) at the cerebral hemisphere,one (8.3％) at the pineal region,one (8.3％) at the suprasellar region,one (8.3％) at the cerebral convexity,one (8.3％) at the cerebellar hemisphere and one (8.3％) at the fourth ventricle.These tumors included immature teratoma (n=3),choroid plexus tumor (n=3),atypical teratoid/rhabdoid tumor (n=2),medulloblastoma (n=1),anaplastic ependymoma (n=1),pilomyxoidastrocytomas (n=1) and infantile fibrosarcoma (n=1).Diversity of MR imaging features was found in different types of brain tumors; tumors as immature teratoma,atypical teratoid/rhabdoid tumor and infantile fibrosarcoma showed mainly mixed signal intensity on T1-weighted images and T2-weighted images,and these tumors displayed heterogeneously enhancement at MR imaging; choroid plexus tumors and medulloblastoma showed isointenseon T1-weighted images and T2-weighted images mostly,and both had obvious enhancement; anaplastic ependymoma showed isointensity signal on T1-weighted images,slightly hyperintenseon T2-weighted images and heterogeneously enhancement; pilomyxoidastrocytomas were hypointenseon Tl-weighted images,hyperintenseon T2-weighted images and homogeneous enhancement.Conclusions Immature teratomas,choroid plexus tumors and embryonal tumors are common in infants.Supratentorial tumors are mostly found.Typical features are showed in some brian tumors,but part of atypical tumors remain challenging in diagnosis.To improve diagnostic accuracy,imaging data should be accumulated in the future.

CT and MR imaging diagnosis of intracranial teratomas / 中华神经医学杂志

Objective To analyze the CT and MR imaging features of intracranial teratomas to improve the diagnostic accuracy.Methods Twenty patients with intracranial teratomas,admitted to and performed surgery in our hospital from January 2010 and January 2014,were chosen;the teratoma was confirmed by histopathology.The CT and MR imaging features,clinical and pathology materials of these patients were retrospectively analyzed.Results Twelve immature teratomas,7 mature teratomas and one teratoma with malignant transformation were noted;18 patients were in the central line area and 2 were not.In the 9 patients performed CT scan,7 showed heterogeneous mass;peritumoral calcification was more common than intratumoral calcification,and it turned out to be round with diameter less than 1 cm,while intratumoral calcification was multifocally strip and patchy.In the 17 patients performed MR imaging,14 showed heterogeneous signal and fatty signal was detected in 3;enhanced MR imaging showed that 6 presented nodular enhancement,3 presented multilocular enhancement markedly,patchy enhancement showed in 2,and one showed marked enhancement in mural nodule and cystic wall.In 8 patients performed diffusion-weighted imaging,7 displayed hypointense to isointense and one demonstrated isointense to hyperintense.Conclusions Intracranial teratoma has some characteristic imaging features,so by combining clinical materials,it should be considered when fatty component is detected in a heterogeneous intensity tumor with multiple cystic change,calcification and a hypointense to isointense signal on DWI;however,pathology is needed to make a definite diagnosis.

Carotid artery plaque burden and composition characteristics measured by 3.0T MRI and its relationship with ischemic stroke / 中华神经医学杂志

Objective To investigate the differences of carotid plaque burden,composition characteristics between index side and non-index side in patients with ischemic stroke by multi-contrast 3.0T MRI,and analyze their relationships with cerebral ischemic events.Methods Sixty-two ischemic stroke patients,admitted to our hospital from 2012 August to 2013 December,were chosen in our study;they all underwent brain routine 3.0T MR imaging examinations within 2 weeks of stoke onset; according to the ischemic signs,the index side and non-index side of the patients were recognized and noted; carotid artery multi-contrast MR imaging was,then,employed to distinguish the discriminant carotid artery plaque components (such as calcification,lipid rich necrotic core [LRNC],intraplaque hemorrhage [IPH])and measure the corresponding volume,to judge the carotid artery plaque fibrous cap surface state (complete or broken) measure the total vessel area,lumen area,wall thickness and calculation wall area and normalized wall index.Results A total of 120 carotid arteries met the inclusion criteria,including 85 in the index side and 35 in the non-index side.LRNC and IPH incidence rates between the index side and non-index side (71.7％ vs.22.8％; 12.9％ vs.0％) and volume (19.96 mm3 [0 mm3,61.91 mm3] vs.0mm3 [0 mm3,0 mm3]; [0 mm3,58.73 mm3] vs.[0 mm3,0 mm3]) were statistically different (P＜0.05).FCR incidence rate showed no significant difference between the index side and non-index side (P＞0.05).The carotid artery average and maximum wall area ([28.06±10.06] mm2 and [47.61±16.82] mm2),average and maximum wall thickness ([1.07±0.37] mm and [2.88±1.72] mm),and average and maximum wall standard index ([0.41 ±,0.09] and [0.54±0.16]) of index side had significant difference as compared with the non-index side([22.50±5.04] mm2 and [36.22±10.53] ram2; [0.88±0.18] mm and [1.91±1.00] mm;[0.36±0.05] and [0.45±0.10],P＜0.05).Conclusion The 3.0T multi-contrast high resolution MRI of the carotid artery can quantitatively measure the carotid plaque burden and evaluate the plaque characteristics; the heavier the plaque burden,the more complex the components,the higher the cerebral ischemic events.

Ultrasmall superparamagnetic iron oxide-enhanced magnetic resonance angiography combined with inflammatory factors for detecting atherosclerotic plaques in rabbits / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the feasibility of Ultrasmall superparamagnetic iron oxide-enhanced magnetic resonance angiography (USPIO-MRA) combined with interleukin-6 (IL-6) and IL-10 detection for detecting atherosclerotic plaques in rabbits.</p><p><b>METHODS</b>Twenty-four normal male rabbits were randomly assigned (n=8) into group A with atherosclerosis induced by damaging the aortic tunica intima with Foley's tube in combination with a high fat diet, group B with a high fat diet, and group C without any intervention. At week 12, plain and USPIO-MRA was performed in all the 24 rabbits and the results were compared with pathological examinations; blood samples were collected from the ear vein to examine blood lipids and levels of IL-6 and IL-10.</p><p><b>RESULTS</b>The rabbits in groups A and B showed significantly different IL-6 levels (167 ± 21.3 vs 116 ± 14.3 pg/ml, P<0.05) but comparable blood lipids and IL-10 levels (P>0.05). The levels of IL-6, IL-10, TC, TG, and LDL, but not HDL, differed significantly between groups A and C and between groups B and C (P<0.01). Continuous MRA scan showed significantly different signal-to-noise ratios (SNR) between the 3 groups.</p><p><b>CONCLUSION</b>USPIO-MRA combined with IL-6 and IL-10 detection is feasible in detecting atherosclerotic plaques in rabbits.</p>

Correlation between MR amide proton transfer signal intensity and pathologic features in brain glioma / 中华放射学杂志

Objective To investigate the probable pathologic basis of amido proton transfer(APT) imaging by analysing APT signal intensity and pathologic features of different grades of glioma.Methods Twenty-eight patients with glioma confirmed by postoperative pathology underwent APT scan.All the patients were divided into two groups,including 11 cases in low grade (WHO Ⅰ and Ⅱ) and 17 cases in high grade (WHO Ⅲ and Ⅳ) group.The APT rate of tumor core was measured.The specimens were processed with routine hematoxylin-eosin (HE) staining and immunohistochemistry of Ki-67 and CD34.Independent-samples t test was used to detect the difference of APT rate,cellularity,microvessel density and Ki-67 labeling indices of tumor core between low grade and high grade group.Pearson correlation analysis and multi-variable linear regression analysis were used to detect the relationship of APT rate with cellularity,microvessel density and Ki-67 labeling indices of the tumor core.Results The APT rate,cellularity and proliferation index were (2.3±0.6) ％,(9.4±2.4) ％ and (14.2±5.4) ％ in low grade group,while (3.6±0.7) ％,(18.4±4.7) ％ and (31.7±4.5) ％ in high grade group,respectively.Microvessel density was (19.0±7.4) per high-power field in low grade group and (38.9±11.3) in high grade group.There were statistical differences of the APT rate,cellularity,microvessel density and proliferation index between the low grade group and the high grade group (t=-4.94,-5.89,-5.13,and-9.28,respectively,P＜0.01).The APT rate was positive correlated with cellularity,microvessel density and proliferation index.The coefficient of correlation were 0.904,0.598,and 0.750,respectively,(P＜0.01).Multiple linear correlative analysis showed that increasing cellularity (X1),microvessel density (X2) and proliferation index (X3) were the main factors for increasing APT rate,and the correlation equation was Y=0.801 + 0.12X1-0.003X2 + 0.026X3 (F=46.437,P＜0.01,R2=0.853).Conclusions The APT signal intensity of the tumor core could reflect the pathologic features of glioma.The APT rate was positive correlated with cellularity,microvessel density and proliferation index,which indicate the higher APT rate the higher grade tumor.

Comparative study of USPIO-enhanced and Gd-enhanced MRI in the diagnosis of atherosclerotic plaques in rabbits / 实用医学杂志

Objective To investigate the imaging characteristics of USPIO-enhanced and Gd-enhanced MRI in atherosclerosis and to compare the detection rate of atherosclerotic plaque between them. Methods Thirty-five healthy male rabbits were assigned to experimental group (n=30) to establish a model of atherosclerosis by damaging aortic tunica intima with Foley′s tube in combination with a high fat diet and 5 to control group without any intervention. At week 12, USPIO-enhanced and Gd-enhanced MRI scanning were conducted to compare the signal changes of atherosclerotic plaque before and after enhancement with the 2 contrast media. Ninety seven pictures were randomly selected respectively from the pictures enhanced by the 2 contrast media to compare the detection rate plaque between them. Pthology examination was used for detection standard. For the control group , pictures were randomly selected. Results In the experimental group, 7 rabbits died of Foley′s tube damaging, 2 died of raising and 1 died of anesthesia. All 5 rabbits in control group survived. A total of 172 pathological sections were made with 134 plaques and 72 vulnerable plaques pathologically confirmed. In pictures enhanced by USPIO , 84 plaques were confirmed by HE staining with a detection rate of 86.6%. In pictures enhanced by Gd, 72 plaques were confirmed by HE staining with a detection rate of 74.2%. Detection rate of USPIO-enhanced MRI in atherosclerosis plaque was significantly higher than that of Gd-enhanced MRI (X2=3.96, P=0.046). Conclusion USPIO shows its superiority as a new contrast medium in detection of atherosclerosis plaque.