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Background: This study aimed to assess the feasibility and performance of 5.0 T MRI in MR Cholangiopancreatography (MRCP) imaging compared to 3.0 T, focusing on detail visualization, signal-to-noise ratio (SNR), and image artifacts. Methods: A prospective study from May to October 2023 involved 20 healthy subjects and 19 with biliary dilation. Both groups underwent MRCP using 3.0 T and 5.0 T scanners. The detail visualization capability of the biliary tree and the SNR of the images were quantitatively evaluated. Two experienced MRI diagnostic physicians assessed the image artifacts qualitatively on a scale of 1 to 5. The t-test or Wilcoxon signed-rank test compared the quantitative results of biliary visualization and SNR between 3.0 T and 5.0 T scanners, while the Wilcoxon signed-rank test was used for comparing the level of image artifacts between the two scanners. The inter reader consistency was tested using Kappa test. Results: In both healthy subjects and those with biliary dilation, the 5.0 T group exhibited significantly higher numbers of biliary tree branches, along with greater total and maximum branch lengths, compared to the 3.0 T group (P<0.05). Although the maximum branch length was higher in the 5.0 T group among healthy subjects, this difference was not statistically significant (P = 0.053). No notable differences were observed in SNR and image artifact levels between the two groups across both field strengths (P>0.05). Conclusions: MRCP at 5.0 T offers superior biliary tree visualization compared to 3.0 T. The performance regarding SNR and image artifacts between the two is relatively comparable. [ABSTRACT FROM AUTHOR]

Background: Ectopic pregnancies (EP) are a common pregnancy complication that's associated with significant morbidity and rarely mortality if not managed properly. Ultrasound examination forms the cornerstone of diagnosis of EP with some sonographic features occasionally not correlating with intraoperative findings. We set out to conduct an audit of EP managed surgically at our hospital for a 10-year period and discern the correlation and prediction of sonographic findings to intraoperative findings. Methods: This study was designed as a Retrospective Observational Study based at the Aga Khan University Hospital (AKUH). Study population was all women admitted to AKUH with a diagnosis of ectopic pregnancy that was surgically managed between the period of January 1st 2011 to December 31st 2020. Analysis of data was done against a pre-set checklist. Descriptive statistics for continuous variables was calculated and tabulated in graphs and tables. SPSS version 22 was used for analysis of data. Results: A total of 337 patients in this study had ultrasound findings. 99.7% (n = 336) of these patients had an intraoperatively confirmed EP. The commonest ultrasound finding was an adnexal mass in 97.1% (n = 309) of patients. These were confirmed surgically in 290 patients at the following locations: 76.6% (n = 222) were ampullary in location; 10.7% (n = 31) were fimbrial in location; 8.6%(n = 25) were isthmic in location; 2.4%(n = 7) were interstitial in location; 1%(n = 3) were abdominal in location; while 0.3% were located in the ovary(n = 1) or round ligament(n = 1) each. Interstitial EP on ultrasound were all (100%) confirmed in the same location intraoperatively, with ampullary EP also correlating fairly well with intraoperative location (75%). The distribution of location in the minor hemoperitoneum (HP) versus major HP groups were similar except for interstitial EP that increased from 1.4% in the minor HP group to 9.5% in the major HP group. Conclusion: In conclusion, ultrasonography still represents the best imaging modality for EP. The most common finding is usually an adnexal mass with no specific location. Most (99.7%) of the patients with this sonographic finding usually have a confirmed EP. Interstitial EP are the most well localized with ultrasound followed by ampullary EP. Furthermore, the presence of major (> 500mls) hemoperitoneum may act as an adjunct for diagnosis of an interstitial EP. [ABSTRACT FROM AUTHOR]

Purpose: Rectal tumor segmentation on post neoadjuvant chemoradiotherapy (nCRT) magnetic resonance imaging (MRI) has great significance for tumor measurement, radiomics analysis, treatment planning, and operative strategy. In this study, we developed and evaluated segmentation potential exclusively on post-chemoradiation T2-weighted MRI using convolutional neural networks, with the aim of reducing the detection workload for radiologists and clinicians. Methods: A total of 372 consecutive patients with LARC were retrospectively enrolled from October 2015 to December 2017. The standard-of-care neoadjuvant process included 22-fraction intensity-modulated radiation therapy and oral capecitabine. Further, 243 patients (3061 slices) were grouped into training and validation datasets with a random 80:20 split, and 41 patients (408 slices) were used as the test dataset. A symmetric eight-layer deep network was developed using the nnU-Net Framework, which outputs the segmentation result with the same size. The trained deep learning (DL) network was examined using fivefold cross-validation and tumor lesions with different TRGs. Results: At the stage of testing, the Dice similarity coefficient (DSC), 95% Hausdorff distance (HD95), and mean surface distance (MSD) were applied to quantitatively evaluate the performance of generalization. Considering the test dataset (41 patients, 408 slices), the average DSC, HD95, and MSD were 0.700 (95% CI: 0.680–0.720), 17.73 mm (95% CI: 16.08–19.39), and 3.11 mm (95% CI: 2.67–3.56), respectively. Eighty-two percent of the MSD values were less than 5 mm, and fifty-five percent were less than 2 mm (median 1.62 mm, minimum 0.07 mm). Conclusions: The experimental results indicated that the constructed pipeline could achieve relatively high accuracy. Future work will focus on assessing the performances with multicentre external validation. [ABSTRACT FROM AUTHOR]

Background: To develop and validate radiomics models for prediction of tumor response to neoadjuvant therapy (NAT) in patients with locally advanced rectal cancer (LARC) using both pre-NAT and post-NAT multiparameter magnetic resonance imaging (mpMRI). Methods: In this multicenter study, a total of 563 patients were included from two independent centers. 453 patients from center 1 were split into training and testing cohorts, the remaining 110 from center 2 served as an external validation cohort. Pre-NAT and post-NAT mpMRI was collected for feature extraction. The radiomics models were constructed using machine learning from a training cohort. The accuracy of the models was verified in a testing cohort and an independent external validation cohort. Model performance was evaluated using area under the curve (AUC), sensitivity, specificity, positive predictive value, and negative predictive value. Results: The model constructed with pre-NAT mpMRI had favorable accuracy for prediction of non-response to NAT in the training cohort (AUC = 0.84), testing cohort (AUC = 0.81), and external validation cohort (AUC = 0.79). The model constructed with both pre-NAT and post-NAT mpMRI had powerful diagnostic value for pathologic complete response in the training cohort (AUC = 0.86), testing cohort (AUC = 0.87), and external validation cohort (AUC = 0.87). Conclusions: Models constructed with multiphase and multiparameter MRI were able to predict tumor response to NAT with high accuracy and robustness, which may assist in individualized management of LARC. [ABSTRACT FROM AUTHOR]

Background: To explore the value of multiparametric MRI markers for preoperative prediction of Ki-67 expression among patients with rectal cancer. Methods: Data from 259 patients with postoperative pathological confirmation of rectal adenocarcinoma who had received enhanced MRI and Ki-67 detection was divided into 4 cohorts: training (139 cases), internal validation (in-valid, 60 cases), and external validation (ex-valid, 60 cases) cohorts. The patients were divided into low and high Ki-67 expression groups. In the training cohort, DWI, T2WI, and contrast enhancement T1WI (CE-T1) sequence radiomics features were extracted from MRI images. Radiomics marker scores and regression coefficient were then calculated for data fitting to construct a radscore model. Subsequently, clinical features with statistical significance were selected to construct a combined model for preoperative individualized prediction of rectal cancer Ki-67 expression. The models were internally and externally validated, and the AUC of each model was calculated. Calibration and decision curves were used to evaluate the clinical practicality of nomograms. Results: Three models for predicting rectal cancer Ki-67 expression were constructed. The AUC and Delong test results revealed that the combined model had better prediction performance than other models in three chohrts. A decision curve analysis revealed that the nomogram based on the combined model had relatively good clinical performance, which can be an intuitive prediction tool for clinicians. Conclusion: The multiparametric MRI radiomics model can provide a noninvasive and accurate auxiliary tool for preoperative evaluation of Ki-67 expression in patients with rectal cancer and can support clinical decision-making. [ABSTRACT FROM AUTHOR]

Objective: To assess the diagnostic efficacy of 18F-FDG PET/MRI for lymph node (LN) metastasis primary staging in patients with colorectal cancer (CRC). Methods: This study was conducted and reported in accordance with the PRISMA-DTA statement. Electronic databases (PubMed, Embase, Cochrane Library) were searched for studies on 18F-FDG PET/MRI for diagnosing LN metastasis. The pooled sensitivity (SEN), specificity (SPE), and area under the curve (AUC) were applied to assess the diagnostic performance. Heterogeneity was identified and processed using meta-regression and sensitivity analysis. All data analyses were performed via STATA 15 and Meta-Disc 1.4 software. Results: There were finally 7 studies included, involving a total of 184 patients. The Spearman rank correlation coefficient was 0.108 (P = 0.818), with no threshold-effect observed. The pooled SEN was 0.81 (95%CI 0.66–0.90) and the SPE was 0.89 (95% CI 0.73–0.96). In sub-groups, prospective groups demonstrated to have the highest SEN of 0.92 (95%CI 0.79–1.00). The studies conducted by Catalano et al. and Kang et al. were considered to be potential sources of heterogeneity. Conclusion: 18F-FDG PET/MRI has shown remarkable diagnostic performance in identification of LN metastases in newly diagnosed CRC patients. It would be of great application value for the primary staging of CRC lymph node metastases. [ABSTRACT FROM AUTHOR]

Background: Preoperative assessment of lymphovascular invasion(LVI) of rectal cancer has very important clinical significance. However, accurate preoperative imaging evaluation of LVI is highly challenging because the resolution of MRI is still limited. Relatively few studies have focused on prediction of LVI of rectal cancer with the tool of radiomics, especially in patients with negative statue of MRI-based extramural vascular invasion (mrEMVI).The purpose of this study was to explore the preoperative predictive value of biparametric MRI-based radiomics features for LVI of rectal cancer in patients with the negative statue of mrEMVI. Methods: The data of 146 cases of rectal adenocarcinoma confirmed by postoperative pathology were retrospectively collected. In the cases, 38 had positive status of LVI. All patients were examined by MRI before the operation. The biparametric MRI protocols included T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI). We used whole-volume three-dimensional method and two feature selection methods, minimum redundancy maximum relevance (mRMR) and least absolute shrinkage and selection operator (LASSO), to extract and select the features. Logistics regression was used to construct models. The area under the receiver operating characteristic curve (AUC) and DeLong's test were used to evaluate the diagnostic performance of the radiomics based on T2WI and DWI and the combined models. Results: Radiomics models based on T2WI and DWI had good predictive performance for LVI of rectal cancer in both the training cohort and the validation cohort. The AUCs of the T2WI model were 0.87 and 0.87, and the AUCs of the DWI model were 0.94 and 0.92. The combined model was better than the T2WI model, with AUCs of 0.97 and 0.95. The predictive performance of the DWI model was comparable to that of the combined model. Conclusions: The radiomics model based on biparametric MRI, especially DWI, had good predictive value for LVI of rectal cancer. This model has the potential to facilitate the clinical recognition of LVI in rectal cancer preoperatively. [ABSTRACT FROM AUTHOR]

Background: Short in-frame deletions in the second extracellular domain of the cytokine receptor gp130 are the leading cause of inflammatory hepatocellular adenomas (IHCAs). The deletions render gp130 constitutively active. In this study we investigate the intracellular signaling potential of one of the most potent constitutively active gp130 mutants (CAgp130) found in IHCAs. Results: Trafficking and signaling of CAgp130 were studied in stably transfected cell lines that allowed the inducible expression of CAgp130 fused to fluorescent proteins such as YFP and mCherry. In contrast to the predominantly highly glycosylated gp130 wild type (WTgp130), CAgp130 is preferentially found in the less glycosylated high-mannose form. Accordingly, the mutated receptor is retained intracellularly and therefore less prominently expressed at the cell surface. CAgp130 persistently activates Stat3 despite the presence of the feedback inhibitor SOCS3 but fails to activate Erk1/2. De novo synthesized CAgp130 signals already from the ER-Golgi compartment before having reached the plasma membrane. Cell surface expressed and endocytosed CAgp130 do not significantly contribute to signaling. As a consequence, Stat3 activation through CAgp130 cannot be inhibited by neutralizing gp130 antibodies but through overexpression of a dominant-negative Stat3 mutant. Conclusion: CAgp130 and WTgp130 differ significantly with respect to glycosylation, trafficking and signaling. As a consequence of intracellular signaling pharmacological inhibition of CAgp130 will not be achieved by targeting the receptor extracellularly but by compounds that act from within the cell. [ABSTRACT FROM AUTHOR]