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@#Objective To investigate the radiomics features to distinguish invasive lung adenocarcinoma with micropapillary or solid structure. Methods A retrospective analysis was conducted on patients who received surgeries and pathologically confirmed invasive lung adenocarcinoma in our hospital from April 2016 to August 2019. The dataset was randomly divided into a training set [including a micropapillary/solid structure positive group (positive group) and a micropapillary/solid structure negative group (negative group)] and a testing set (including a positive group and a negative group) with a ratio of 7∶3. Two radiologists drew regions of interest on preoperative high-resolution CT images to extract radiomics features. Before analysis, the intraclass correlation coefficient was used to determine the stable features, and the training set data were balanced using synthetic minority oversampling technique. After mean normalization processing, further radiomics features selection was conducted using the least absolute shrinkage and selection operator algorithm, and a 5-fold cross validation was performed. Receiver operating characteristic (ROC) curves were depicted on the training and testing sets to evaluate the diagnostic performance of the radiomics model. Results A total of 340 patients were enrolled, including 178 males and 162 females with an average age of 60.31±6.69 years. There were 238 patients in the training set, including 120 patients in the positive group and 118 patients in the negative group. There were 102 patients in the testing set, including 52 patients in the positive group and 50 patients in the negative group. The radiomics model contained 107 features, with the final 2 features selected for the radiomics model, that is, Original_ glszm_ SizeZoneNonUniformityNormalized and Original_ shape_ SurfaceVolumeRatio. The areas under the ROC curve of the training and the testing sets of the radiomics model were 0.863 (95%CI 0.815-0.912) and 0.857 (95%CI 0.783-0.932), respectively. The sensitivity was 91.7% and 73.7%, the specificity was 78.8% and 84.0%, and the accuracy was 85.3% and 78.4%, respectively. Conclusion There are differences in radiomics features between invasive pulmonary adenocarcinoma with or without micropapillary and solid structures, and the radiomics model is demonstrated to be with good diagnostic value.
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<p><b>BACKGROUND</b>Balanced steady-state free precession MR angiography (b-SSFP MRA) has shown great promise in diagnosing renal artery stenosis (RAS) as a non-contrast MR angiography (NC-MRA) method. However, results from related studies are inconsistent. The purpose of this meta-analysis was to assess the accuracy of b-SSFP MRA compared to contrast-enhanced MR angiography (CE-MRA) in diagnosing RAS.</p><p><b>METHODS</b>English and Chinese studies that were published prior to September 4, 2013 and that assessed b-SSFP MRA diagnostic performance in RAS patients were reviewed. Quality of the literature was assessed independently by two observers. The statistical analysis was adopted by the software of Meta-Disc version 1.4. Using the heterogeneity test, a statistical effect model was chosen to calculate different pooled weighted values. The receiver operator characteristic (ROC) space and Spearman correlation coefficient were to explore threshold effect. Sensitivity analysis and the publication bias were performed to demonstrate if the pooled estimates were stable and reliable. We produced forest plots to calculate the pooled values and corresponding 95% confidence interval (CI) of sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and constructed a summary receiver operating characteristic curve (SROC) to calculate the area under the curve (AUC).</p><p><b>RESULTS</b>A total of 10 high quality articles were used in this meta-analysis. The studies showed a high degree of heterogeneity. The "shoulder-arm" shape in the ROC plot and the Spearman correlation coefficient between the log(SEN) and log(1-SPE) suggested that there was a threshold effect. Sensitivity analysis demonstrated that the actual combined effect size was equal to the theoretical combined effect size. The publication bias was low after quality evaluation of the literature and the construction of a funnel plot. The pooled sensitivity was 0.88 (95% CI, 0.83-0.91) and pooled specificity was 0.94 (95% CI, 0.93-0.95); pooled PLR was 14.57 (95% CI, 9.78-21.71]) and pooled NLR was 0.15 (95% CI, 0.11-0.20). The AUC was 0.964 3.</p><p><b>CONCLUSION</b>In contrast to CE-MRA, the b-SSFP MRA is more accurate in diagnosing RAS, and may be able to replace other diagnostic methods in patients with renal insufficiency.</p>
Subject(s)
Humans , Angiography , Methods , Contrast Media , Magnetic Resonance Angiography , Renal Artery Obstruction , DiagnosisABSTRACT
Objective To investigate the value of diffusion-weighted imaging(DWI) in diagnosing the feminine pelvic lesions.Methods Conventional MRI and DWI with b value of 0 and 1000 s/mm2 respectively were performed in 135 feminine patients with pelvic lesions. Apparent diffusion coefficient (ADC) values of the lesions were measured. Contrast-enhancement MR imaging was performed in 16 patients.Results The average ADC values were (0.90?0.10)?10-3mm2/s in uterine malignant lesions (43 cases),(0.12?0.09)?10-3mm2/s in uterine benign lesions ( 24 cases ) , ( 0.98?0.11 )?10-3mm2/s in adnexal malignant diseases ( 34 cases ) and ( 2.25?0.12)?10-3mm2/s in adnexal benign ones(34 cases), respectively.There were significant differences between malignant and benign groups(P
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Objective To evaluate the diagnostic value of magnetic resonance urography(MRU)in patients with iatrogenic ureteral injuries.Methods MRU in 12 patients with iatrogenic ureteral injuries caused by gynecological and rectal operation were performed.Results MRU examinations were successfully done in all cases at once.The accurate rate in localized and qualitative diagnosis was all 100%.The injures of ureter in 12 cases were all located at lower segment of the ureter,of them,8 patients were purely obstruction,4 cases were obstruction with urinal leakage,all cases were accompanied by dilations of ureter and hydronephrosis.Conclusion MRU is helpful for the diagnosis of iatrogenic ureteral injury.