Objective To develop a practical testing system on internet,to offer a modern pattern of practicing testing for diagnostic imaging and to evaluate the effects.Methods Practical testing system for diagnostic imaging based on PACS was set up and its effect was evaluated by students.Results The developed practical testing system combines question bank,image reading tool and answering interface together and has functions of controlling and managing both the questions and students participating in the examination.In the satisfaction survey of students,practicing testing system of diagnostic imaging got a score of 96.75 (full mark 100) and was highly prized.Conclusions This pattern of online testing offers more imaging information and makes practicing examination of diagnostic imaging more vivid and scientific.

Objective To explore the value of abnormal imaging findings on susceptibility weighted imaging (SWI) in delayed graft function (DGF). Methods The conventional MRI and SWI images of 26 cases with DGF and 20 cases with normal renal function of transplanted kidneys were retrospectively analyzed. Patients with cysts and angiomyolipomas were excluded. Normal structures of transplanted kidney were identified. If lesions of abnormal signal intensity were found in the transplanted kidney, the location, border and signal intensity compared to renal cortex would be analyzed. The differences in signal intensity between the abnormal signal lesions and normal renal cortex in the same SWI layer of DGF were compared by using independent-sample t test. The differences in positive detection rate of discovering the abnormal signal lesions in DGF between conventional MRI and SWI were compared by using McNemar test. Results Of the 26 cases with DGF, one case was found to exhibit abnormally low signal lesions with fuzzy boundary located at junctional zone between cortex and medulla on both conventional MRI and SWI images. Ten cases were found to exhibit abnormally low signal lesions with fuzzy boundary located at junctional zone between cortex and medulla on SWI images only. Fifteen cases exhibited no abnormal signal lesions on both conventional MRI and SWI images. Twenty cases with normal renal function of transplanted kidney, no abnormal signal lesions were found on both conventional MRI and SWI images. The differences in signal intensity between the abnormally low signal lesions (130±20) and normal renal cortex (177±25) in the same SWI layer of 11 cases with DGF were statistically significant (t=-4.582,P<0.01). The differences in positive detection rate of discovering the abnormally low signal lesions in DGF between conventional MRI [3.8%(1/26)] and SWI [42.3% (11/26)] were statistically significant (χ2=8.100,P=0.002). Conclusions Abnormally low signal lesions with fuzzy boundary located at junctional zone between cortex and medulla on SWI images suggest the presence of DGF. Compared with conventional MRI, SWI appears to be superior in detecting the abnormally low signal lesions.

Objective To evaluate dynamic CT and PET-CT features of normal dog liver after radiofrequency ablation(RFA)correlated with the time-related histopathological changes.Methods Fifteen hybrid adult dogs in good health condition were evenly divided into 5 groups(the immediate,1 st,2 nd,4 th and 8 th week group)according to random digits table methods.Twice RFA was performed for each dog liver.The dogs after RFA underwent CT and PET-CT scanning respectively at the time point defined for each group.All dogs were executed through intravenous injection of klorvess liquid after scanning.Liver samples were histologically examined.All images were assessed to determine the ratios(r_(p/p))which referred to the comparison of rimlike enhancement or tracer uptake in the periphery of the necrosis to that in normal liver parenchyma.Those imaging results were compared and correlated with histopathological findings.Results For the immediate group after RFA procedure,central ablation lesions appeared coagulation necrosis and surrounding sinusoids engorged with blood.On the images of enhanced CT,marked rimlike enhancement was noticed in peripheral ablation lesions.While PET-CT showed decreased ~(18)F-FDG uptake surrounded by homogeneous tracer distribution.For the 1 st-4 th week group,central necrosis was gradually getting more severe.Infiltration of the inflammatory cells,granulation tissue formation and fibrous tissue restoration were noticed in peripheral ablation lesions.Rimlike enhancement and increased glucose metabolism appeared surrounding the lesions on CT and PET-CT,especially in the 1st to 2nd week groups.For the 8 th week group after RFA,the enhancement or hypermetabolism metioned above disappeared when perilesional tissue regeneration became more obvious.From the dynamic curve of changes on enhanced CT,marked enhancement occurred in the immediate group after ablation(r_(p/p)=1.34±0.21),reached its peak at the 1st week group(r_(p/p)=1.39±0.20),and then declined gradually.The metabolic changes on PET-CT showed a typical single peak curve,with the peak at the 1st week group(r_(p/p)=1.19±0.09)and similar even metabolism at the immediate and 8 th week group.Conclusions Both CT and PET-CT imaging can well correlate with the histopathological changes after RFA in the normal liver.To avoid the interference of inflammatory reaction when differentiating normal liver tissue from residual tumor,it is better to take radiology examination immediately and 8 weeks after RFA.PET-CT probably has advantages over CT immediately after RAF.After 1 week,PET-CT and CT may have similar diagnostic efficacy.

Objective: To detect the values of CT texture features in the preoperative prediction of Fuhrman grade of clear cell renal cell carcinoma (ccRCC). Methods: The CT data of 206 patients with ccRCC admitted to the Third Affiliated Hospital of Soochow University from January 2011 to December 2016 were retrospectively analyzed, and the ccRCC cases were graded using Fuhrman grading system, including 38 cases of Grade Ⅰ, 107 cases of Grade Ⅱ, 50 cases of Grade Ⅲ and 11 cases of Grade Ⅳ. All subjects undergone plain and enhancement CT scans. There were two methods used for the extraction of texture features, including histogram (2 features: Kurtosis and Skewness) and gray-level co-occurrence matrix (6 features: Contrast, Correlation, Energy, Entropy, Homogeneity and Variance). Each texture feature during Grade Ⅰ to Ⅳ was compared using a one-way analysis of variance following the log-ratio transformation, and a Newman-Keuls test was performed for all pairwise comparisons. An independent sample t test was used to find the differences of each texture feature between low (Grade Ⅰ+Ⅱ) and high grade (Grade Ⅲ+Ⅳ) ccRCC. A Spearman Rank test was performed to quantify the correlation of each texture feature with Fuhrman grade in ccRCC. Receiver operating characteristic curve (ROC) was employed to compare the diagnostic performance of the texture features to differentiate the low grade from high grade ccRCC. Results: Six texture features, including Contrast, Correlation, Entropy, Homogeneity, Variance and Kurtosis, were different during Grade Ⅰ to Ⅳ (all P<0.05) with the exception of the two features of Energy and Skewness (all P>0.05). Furthermore, five textures, such as Correlation, Entropy, Homogeneity, Variance and Kurtosis, were not significantly different between Grade Ⅲ and Ⅳ ccRCC. There was no clinical application value for the features of Correlation, Energy, Entropy, Variance and Skewness with the absolute coefficients of<0.3, in contrast, the correlation coefficients were -0.54, 0.39 and 0.32 for the features of Contrast, Homogeneity and Kurtosis, respectively (all P<0.05). Compared with that in the low grade ccRCC, the values of Contrast and Variance reduced in the high grade ccRCC (all P<0.05), while the values of Kurtosis, Correlation and Homogeneity increased significantly in the high grade ccRCC (all P<0.05), and no difference was found for the features of Skewness, Energy and Entropy between the low and high grade ccRCC (all P>0.05). When those features were used to differentiate the high from low grade ccRCC, the Contrast exhibited the biggest area under ROC of 0.806 (P<0.05), followed by the Correlation of 0.641, Homogeneity of 0.687, Kurtosis of 0.668 and Variance of 0.659. Conclusion CT texture features can preoperatively predict the Fuhrman grade of ccRCC, and the Contrast will likely be the potential imaging biomarker for the clinical application.

Objective: To investigate the influence of extremely low-frequency magnetic field on periodical expression of cryptochrome (Cry) gene in mouse embryonic fibroblast NIH3T3 cells. Methods: The NIH3T3 cells were divided into magnetic field group and sham-exposure group. The NIH3T3 cells in the magnetic field group were stimulated by horse serum and then exposed to an extremely low-frequency magnetic field (50 Hz and 0.3 mT) for 48 hours, and those in the sham-exposure group were also stimulated by horse serum and then exposed to a coil for 48 hours. The NIH3T3 cells were collected, total RNA was extracted, and cDNA was obtained via reverse transcription. Real-time fluorescent quantitative RT-PCR was used to measure the changes in transcription cycles of Cry and Period genes in both groups. Results: There was no significant difference in the proliferation rate at 0, 12, 24, and 48 hours of exposure between the two groups (P>0.05) . Both sham-exposure group and magnetic field group showed a rhythmic change in the expression of Cry gene, and compared with the sham-exposure group, the magnetic field group had a significantly shortened circadian rhythm of Cry gene in NIH3T3 cells (t=2.57, P<0.05) . Both groups had rhythmic and periodical expression of Period gene and there was no significant difference between the two groups (t=0.70, P>0.05) . Conclusion Extremely low-frequency magnetic field can significantly shorten the circadian rhythm of Cry gene in mouse embryonic fibroblasts, while there is no significant change in the circadian rhythm of Period gene.

Benign tumors of the parotid gland are common tumors of the head and neck. Surgical resection is considered the main treatment. For the treatment of benign parotid tumors, different surgical approaches can be applied based on many factors, such as tumor type, size, location, depth of tumor and patient requirements, such as improved periauricular incision and improved facial wrinkle removal incision, to achieve the best therapeutic effect. In parotidectomy, the facial nerve, great auricular nerve and parotid duct should be protected as much as possible to preserve the function of the nerve and gland and reduce postoperative complications. In addition, complications after parotidectomy, such as facial nerve injury, salivary fistula, Frey syndrome, postoperative facial depression, abnormal ear sensation and recurrence, should be actively prevented and treated early after the operation, consequently minimizing the impact on patients' postoperative life and improving patients' satisfaction with the operation.

OBJECTIVE:Cement-augmentation pedicle screws have been widely used in spinal internal fixation surgery combined with osteoporosis in recent years,which can significantly improve the fixation strength,but compared with conventional methods,whether it has more advantages is still inconclusive of evidence-based medicine.To systematically evaluate the efficacy and safety of cement-augmented pedicle screw in the treatment of thoracolumbar degenerative diseases with osteoporosis. METHODS:Clinical controlled trials concerning the cement-augmented pedicle screw and the traditional pedicle screw placement for thoracolumbar degenerative diseases with osteoporosis were retrieved from the electronic databases such as CNKI,CBM,WanFang,VIP,PubMed,Cochrane Library,Web of Science and Embase.According to the unified criteria,we performed literature screening and quality evaluation.The meta-analysis was performed using RevMan 5.4 software. RESULTS:(1)Totally 20 articles were selected eventually,involving 2 randomized controlled studies and 18 retrospective cohort studies,totally 1 566 patients.Among them,789 cases were in the cement-augmented screw group and 777 cases in the conventional screw group.(2)Meta-analysis results showed that Japanese Orthopaedic Association score,intervertebral space height and fusion rate were higher in the cement-augmented screw group than those in the conventional screw group(MD=1.60,95%CI:1.14,2.07,P<0.000 01;MD=1.26,95%CI:0.62,1.90,P=0.000 1;OR=11.24,95%CI:2.86,44.14,P=0.000 5).Operation time was longer in the cement-augmented screw group than that in the conventional screw group(SMD=0.82,95%CI:0.42,1.23,P<0.000 1).Postoperative visual analog scale score,Oswestry dysfunction index score and incidence of screw loosening were lower in the cement-augmented screw group than those in the conventional screw group(MD=-0.50,95%CI:-0.78,-0.21,P=0.000 7;SMD=-0.49,95%CI:-0.88,-0.10,P=0.01;OR=0.08,95%CI:0.05,0.12,P<0.000 01).Hospitalization time,intraoperative blood loss,and postoperative drainage volume were not significantly different between the two groups(P>0.05). CONCLUSION:Compared with conventional pedicle screw placement,cement-augmented pedicle screw is more effective in the treatment of osteoporotic thoracolumbar degenerative disease by improving fusion rate and interbody height,reducing the incidence of screw loosening,and elevating long-term efficacy.

Objective:To explore the value of susceptibility-weighted imaging (SWI) in quantitative evaluation of iron load in diabetic kidneys.Methods:Thirty two healthy New Zealand white rabbits were randomly divided into diabetic group (DM, n = 20) and control group (NC, n = 12). DM model was established by injecting 5% alloxan solution (100 ml/kg) through ear vein. 12 rats were finally enrolled into the group. NC group was injected with the same dose of normal saline. DM group and NC group were intramuscularly injected with 60 mg/kg iron dextran. The left kidney was scanned by MRI immediately after iron injection (0 weeks) and 12 weeks after feeding. The left kidney was killed after 12 weeks of scanning. The left kidney was examined by Prussian blue staining and atomic absorption spectrophotometer. The value of SWI in quantitative evaluation of renal iron content was evaluated by using the iron content measured by atomic absorption spectrophotometer as the gold standard. On SWI phase diagram, the region of interest (ROI) was manually drawn along the renal cortical vagal area, and the measured phase values were converted into angular radians. Mann Whitney U test was used to compare the blood glucose value and the angle radian value at 0 week and 12 week between the two groups; independent sample t test was used to compare the difference of iron content between the two groups; nonparametric Wilcoxon signed rank test was used to compare the difference of angle radian between DM group and NC group at 0 and 12 weeks; Spearman correlation analysis was used to study the correlation between angle radian value and atomic absorption spectrophotometer results. Results:The blood glucose level in DM group [28.0 (10.6) mmol/L] was significantly higher than that in NC Group [6.5 (1.9) mmol/L], and the difference was statistically significant (U = 0, P<0.001). At week 0, there was no significant difference between DM group [-0.04 (-0.02)] and NC Group [-0.02 (0.06)] in angle radian value (U=105.50, P>0.05); at 12 weeks, the angle radian value of DM group [0.22 (0.17)] was higher than that of NC Group [0.17 (0.05)], the difference was statistically significant (U=35.50, P<0.05). The angle radian of DM group and NC group at 12 weeks were higher than that of 0 weeks, and the differences were statistically significant ( P<0.05). Prussian blue staining showed that iron was mainly deposited in renal cortex, and the blue staining in DM group was more obvious than that in NC group. The signal intensity of renal cortex on SWI images in DM group was significantly lower than that in 0 week group at 12 weeks, and slightly decreased in NC group. The iron content of DM group and NC group were (171.39±20.13) mg/kg and (116.21±28.90) mg/kg, respectively, and the difference was statistically significant ( t=5.428, P<0.001). Spearman correlation analysis showed that the angle radian was positively correlated with iron content ( r=0.67, P<0.001). Conclusions:Diabetic kidneys have more iron deposits than normal kidneys. As a non-invasive, simple and convenient examination technique, SWI has the potential to quantitatively evaluate the iron load of diabetic kidneys.

Objective:To investigate the value of multimodal MRI radiomics in the preoperative prediction of Fuhrman nuclear grade of clear cell renal cell carcinoma (ccRCC).Methods:A total of 129 patients with ccRCC confirmed by pathology from April 2011 to April 2021 in Third Affiliated Hospital of Soochow University were collected, and the imaging and clinicopathological data were retrospectively analyzed. All patients were divided into training set ( n=90) and validation set ( n=39) at the ratio of 7∶3 using random indicator method. According to the postoperative pathological results, Fuhrman grades Ⅰ and Ⅱ were included in the low grade group (96 cases, 65 cases in the training set and 31 cases in the validation set), and Fuhrman grades Ⅲ and Ⅳ were included in the high grade group (33 cases, 25 cases in the training set and 8 cases in the validation set). Two radiologists manually delineated regions of interest (ROI) on T 1WI, T 2WI, Dixon-water, Dixon-fat, susceptibility weighted imaging (SWI), blood oxygen level dependent (BOLD) images, and 396 texture features were extracted from each ROI. In the training set, intra-class correlation coefficient, Mann-Whitney U test, minimum redundancy maximum relevance and least absolute shrinkage and selection operator method were used to reduce the dimension of features to obtain the best texture features. The logistic regression was used to develop the multimodal radiomics model, and the receiver operating characteristic (ROC) curve was used to evaluate the effectiveness of the model in identifying high and low-grade ccRCC in training set and validation set. Results:Four SWI, one T 2WI and one BOLD texture features were selected for modeling. The areas under the ROC curve (95%CI) of the multimodal radiomics model for identifying high and low grade ccRCC in the training and validation sets were 0.859 (0.770-0.923) and 0.883 (0.740-0.964), with the specificity at 95.4% and 87.1%, the sensitivity at 68.0% and 87.5%, the accuracy at 87.8% and 87.2%, respectively. Conclusion:The multimodal MRI radiomics model based on T 2WI, SWI and BOLD images has high effectiveness in preoperative predicting Fuhrman nuclear grade of ccRCC.

Objective: To investigate the role of lncRNAs in the invasion and metastasis of salivary adenoid cystic carcinoma (SACC) cells. Methods: With SACC-LM as the experimental group and SACC83 as the control group, lncRNA chips were used to screen the differentially expressed lncRNAs. The differentially expressed lncRNAs were further verified by real-time quantitative RT-PCR (qRT-PCR). The invasion and migration abilities of the adenoid cystic carcinoma cell lines before and after transfection with lncRNA siRNAs were detected by invasion and migration experiments. The clinicopathological features and prognosis of patients with different expression of lncRNAs and SACC were analyzed. Results: The microarray showed that ADAMTS9-AS2 was highly expressed in the SACC-LM cells. Real-time quantitative RT-PCR further confirmed that ADAMTS9-AS2 was significantly upregulated in the SACC-LM cells. Invasion and migration experiments showed that the invasion and migration were significantly reduced after the expression level of ADAMTS9-AS2 was downregulated (P ＜ 0.001). Analysis of the clinicopathological data showed that ADAMTS9-AS2 was highly expressed in SACC. High expression of ADAMTS9-AS2 was associated with poor prognosis and a high tumor metastasis rate in SACC patients. Conclusion High expression of ADAMTS9-AS2 promotes the migration and invasion of SACC cells. ADAMTS9-AS2 is upregulated in the SACC tissues and is related to a high metastasis rate and poor prognosis.