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Background: Vesical Imaging‐Reporting and Data System (VI‐RADS) has been developed for assessing bladder cancer from multiparametric (mp) MRI but its performance in diagnosing muscle‐invasive bladder cancer (MIBC) is suboptimal. Purpose: To investigate associations between normalized apparent diffusion coefficient (NADC) and clinicopathological characteristics and to determine whether the inclusion of NADC can improve the performance of VI‐RADS in diagnosing MIBC. Study Type: Retrospective. Population: Two hundred seventy‐five patients with pathologically confirmed bladder cancer (101 MIBC and 174 non‐MIBC [NMIBC]) underwent preoperative mpMRI (233 male, 42 female). Field Strength/Sequence: 3‐T, T2‐weighted imaging (turbo spin‐echo), diffusion‐weighted imaging (free‐breathing spin‐echo), and dynamic contrast‐enhanced imaging (gradient‐echo). Assessment: NADC was the mean ADC of tumor divided by that of the iliopsoas muscles in trans caput femoris plane. Associations between NADC and clinicopathological characteristics were evaluated. Models were established for differentiating MIBC and NMIBC: VI‐RADS model; VN model (VI‐RADS and NADC), Images model (significant variables from imaging associated with MIBC), LN model (Images model without NADC), and Full model (all significant variables associated with MIBC). Statistical Tests: Variables for model development were based on logistic regression. Models were evaluated by receiver operating characteristic (ROC) curve. Comparison of the area under the curves (AUCs) for the models used DeLong's test. A P value <0.05 was considered statistically significant. Results: NADC was significantly lower in lesions with diameter ≥ 3 cm, MIBC, histological high grade, lymph node metastasis, and lymphovascular invasion. Compared with VI‐RADS model, the AUCs for VN model (VI‐RADS score and NADC), Images model (VI‐RADS score, NADC and tumor size) and Full model (VI‐RADS score, NADC, tumor size and histological grade) were significantly higher. No significant differences were observed between the AUCs for VN model and Images model (P = 0.051). Data Conclusion: NADC reflects information about the aggressiveness of bladder cancer. Combining VI‐RADS with NADC can improve performance in diagnosing MIBC. Evidence Level: 4 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

Background: The relationship between tumor and muscle layer in the vesical imaging‐reporting and data system (VI–RADS) 3 is ambiguous, and there is a lack of preoperative and non‐invasive procedures to detect muscle invasion in VI‐RADS 3. Purpose: To develop a nomogram based on MRI features for detecting muscle invasion in VI–RADS 3. Study Type: Retrospective. Population: 235 cases (Age: 67.5 ± 11.5 years) with 11.9% females were randomly divided into a training cohort (n = 164) and a validation cohort (n = 71). Field Strength/Sequence: 3T, T2‐weighted imaging (turbo spin‐echo), diffusion‐weighted imaging (breathing‐free spin echo), and dynamic contrast‐enhanced imaging (gradient echo). Assessment: 3 features were selected from the training cohort, including tumor contact length greater than maximum tumor diameter (TCL > Dmax), flat tumor morphology, and lower standard deviation of apparent diffusion coefficient (ADCSD). Three readers assessed VI‐RADS scores and the tumor morphology. Statistical Tests: Interobserver agreement was assessed by Kappa analysis. Features for final analysis were selected by logistic regression. The performance of the nomogram was evaluated by the receiver operating characteristic curve, decision curve analysis, and calibration curve. Results: TCL > Dmax, flat morphology, and lower ADCSD were the independent risk factors for muscle invasive in VI‐RADS 3. The AUCs, accuracy, sensitivity, and specificity of the nomogram 1 composed of three features for detecting muscle invasion were 0.852 (95% CI: 0.793–0.912), 0.756, 0.917, and 0.663 in the training cohort, and 0.885 (95% CI: 0.801–0.969), 0.817, 0.900, and 0.784 in the validation cohort. The nomogram 2 without ADCSD has nearly the same performance as the nomogram 1. Data Conclusion: Nomogram can be an efficient tool for preoperative detection of muscle invasion in VI–RADS 3. Level of Evidence: 3 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

Hydrocyclones can be used to concentrate the entrained sands in sewage and alleviate the clogging and erosion of the drainage network, but in practical application, there are problems such as low concentrations of underflow and a high content of fine particles, which cause a significant load on the subsequent sand dewatering and recycling. This paper designs five spigot structures of hydrocyclones and investigates the separation performance by numerical simulation, aiming to improve the applicability of hydrocyclones in the sewage treatment process by optimizing the spigot structure. The research results show that a large cone spigot delays the external downward swirling flow and reduces fine particle content in the underflow, but its effective separation space is reduced, and the turbulence in the cone section area is more intensive, which influences the separation accuracy. An elongated spigot has a reduced underflow water distribution; fine particles are more enriched in the internal swirling flow, and the underflow recoveries of 1 μm and 5 μm particles drop by 2.34% and 2.31%. The spigot structure affects the downward fluid and air intake states; complicated spigot structures contribute to increasing the resistance of particle discharge through underflow, alleviating fine particle misplacement. [ABSTRACT FROM AUTHOR]

Background: Vesical Imaging–Reporting and Data System (VI‐RADS) is widely used to assess the muscle‐invasive status of bladder cancer. However, the current classification efficacy of VI‐RASD 2 tumors of stalk is unsatisfactory. Purpose: To develop a nomogram to assess muscle‐invasive bladder cancer (MIBC) in VI‐RADS 2 tumors with stalk. Study Type: Retrospective. Population: A total of 186 patients (age: 67.8 ± 12.7 years) with 15.1% females, divided randomly into a training cohort (N = 130) and validation cohort (N = 56). Field Strength/Sequence: 3‐T, T2‐weighted imaging (turbo spin‐echo), diffusion‐weighted imaging (breathing‐free spin‐echo), and dynamic contrast‐enhanced imaging (gradient‐echo). Assessment: Twenty‐one MRI features of tumors and stalks were developed from training cohort. The mean apparent diffusion coefficient (ADC) values of the tumor, stalk, and psoas muscles were calculated from the three circular regions of interest. The normalized T value=meanADCtumormeanADCmuscle. The normalized ST value=meanADCstalkmeanADCtumor. Three readers assessed the morphology of tumors and stalks. Statistical Tests: The final features of nomogram were selected by univariable logistic and the least absolute shrinkage and selection operator (LASSO) regression. The performance of the nomogram was assessed by the receiver operating characteristic (ROC) curve, calibration, and decision curve analysis. Results: In VI‐RADS 2 tumors with stalk, tumor size over 3 cm, increased stalk width, stalk morphology, decreased normalized T value, and increased normalized ST value were selected as the risk factors for MIBC. The AUC, accuracy, sensitivity, and specificity of the nomogram to assess MIBC were 0.969 (95% CI: 0.941–0.997), 92.3%, 94.1%, and 92.0% in training cohort and 0.940 (95% CI: 0.859–1.000), 89.3%, 75.0%, and 91.7% in validation cohort. Data Conclusion: This study constructed a nomogram for preoperative assessment of MIBC and modifying the current VI‐RADS. Level of Evidence: 3 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]