Objective: To explore the value of spectral CT in differentiating pure and impure cholesterol stones. Methods: Spectral CT was used to scan in vitro gallstones, and infrared spectroscopy spectrum was used to observe the composition and classification of gallstones. ROIs were outlined in the axial, coronal and sagittal maximum planes of gallstones. Spectral CT indexes, including spectral curves, CT value, CT slope, effective atomic number (Zeff) and calcium-water ratio (CWR)) of the stones were acquired. Mann-Whitney U test was used to analyze the differences of parameters among different gallstone groups and subgroups. ROC curve was used to determine the diagnostic threshold, sensitivity, specificity, positive predictive value and negative predictive value of pure and impure cholesterol stone group. Results: There were significant differences of CT parameters between pure and impure cholesterol stone groups (all P<0.01). The AUC of the different parameters in differetical the pure and impure cholesterol stone had no statistical difference (all P>0.05). Conclusion: The parameters of pure and impure cholesterol stones have good diagnostic efficacies. There are differences of energy spectrum curves of gallstones with different compositions.

Objective:To explore the value of metal artifact reduction in oblique sagittal multi-acquisition with variable resonance image combination slab selectivity (MAVRIC-SL) inversion recovery (IR) sequence compared with conventional fast spin-echo (FSE) fat saturation (FS)-T 2WI and proton density weighted imaging (PDWI) on the postoperative review of patients with metal-fixed anterior cruciate ligament reconstruction (ACLR) at 3.0 T MR. Methods:From June to November 2018, 27 patients with metal fixtures in ACLR were prospectively recruited in the First Hospital of China Medical University. The FSE sequences (FS-T 2WI and PDWI) and the MAVRIC-SL IR were performed at 3.0 T MRI system. The maximum artifact slice was selected and ROI was drawn, then the implant and artifact area and the number of artifact-influence slices were recorded. Image signal-to-noise ratio (SNR) was calculated. The degree of image artifacts (artifact degree of spiked ligament staple and its influence on the diagnosis of surrounding structures), measurability (measurability of distance between the upper edge of the staple and the lower edge of the graft entrance on tibia), and other degree of artifacts (whether there were metal artifacts other than implants that affect the observation of other structures within the scanning range) were scored. The Friedman M test and pairwise comparison were used to compare and analyze the quantitative and qualitative data. Results:The differences in artifact area, the number of artifact-influence slices and SNR among FS-T 2WI, PDWI and MAVRIC-SL IR images were statistically significant (all P<0.001). Pairwise comparison analysis suggested that the metal implant artifact area and the number of artifact-influence slices in the MAVRIC-SL IR image were smaller, and the SNR was higher than those of FS-T 2WI and PDWI (all P<0.05 after correction). The differences of the three scores among FS-T 2WI, PDWI and MAVRIC-SL IR were statistically significant (all P<0.001). Pairwise comparison analysis suggested that the degree of image artifacts score of MAVRIC-SL IR sequence was lower, and the measurability and other degree of artifacts scores were higher than FS-T 2WI and PDWI (all P<0.05 after correction). Conclusion:MAVRIC-SL can significantly reduce the metal artifacts and improve image quality in the postoperative MRI review of the patients with metal-fixed ACLR. Therefore, oblique sagittal MAVRIC-SL IR sequence can be used for assisting the diagnosis of conventional FS-T 2WI and PDWI.

The histopathological growth pattern (HGP) of colorectal cancer liver metastasis (CRLM) is correlated with the prognosis of patients. Patients with desmoplastic HGP have a better prognosis. The latest international scoring guidelines have modified the cut-off value of HGP, and divides it into two types: complete desmoplastic HGP and incomplete desmoplastic HGP. However, the relationship between the HGPs and the treatment response to systemic treatment is still unclear. It is necessary to develop non-invasive methods to evaluate changes in HGP during treatment in the future. This paper reviews the new scoring consensus and clinical applications of HGP in CRLM.

Objective:To investigate the changes of cardiac morphology and function in obese patients after bariatric surgery.Methods:The clinical data of 100 patients who underwent bariatric surgery, including gastric sleeve resection and gastric bypass in Beijing Friendship Hospital, Capital Medical University from January 2018 to December 2021 were selected for retrospective analysis, including 67 females and 33 males, aged from 18 to 65 years, with average of (36.7±9.5) years. The software of SPSS 26.0 was used to conduct data analysis. Univariate and Logistic regression analysis was performed on the indicators of patients before bariatric surgery and 1 year after surgery, and ROC curves were drawn to determine the changes of cardiac morphology and cardiac function after bariatric surgery.Results:Compared with preoperative, one year after bariatric surgery, patients′ body weight [(112.2±30.2) kg vs(80.7±23) kg, P<0.001] and body mass indes [(38.77±8.26) kg/m 2vs (27.98±6.54) kg/m 2, P<0.001] were significantly decreased, and systolic and diastolic blood pressure, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglyceride, blood uric acid, and resting heart rate were also significantly decreased ( P<0.05), cardiac ejection fraction was significantly improved [(65.5±5.9)% vs (67.9±4.7)%, P<0.001], ventricular septum, left ventricular posterior wall, left atrial diameter, left ventricular systolic and end-diastolic diameter were significantly reduced ( P<0.05), while the inner diameter of the ascending aorta was not significantly changed [(3.14±0.39) cm vs (3.09±0.38) cm, P=0.125]. In addition, there were no significant differences in cardiac morphology between gastric bypass and gastric sleeve resection. Logistic regression analysis showed that pre-bariatric BMI value, postoperative BMI reduction value, whether suffering from hypertension, and whether the inner diameter of the ascending aorta was widened were the important influencing factors for the improvement of ejection fraction after bariatric surgery ( P<0.05). The area under the ROC curve for predicting the improvement of ejection fraction was 0.772 (95% CI: 0.669-0.875), the specificity was 85%, the sensitivity was 66%, and the best cut-off point was 0.545. Conclusions:One year after bariatric surgery in obese patients, cardiac ejection fraction was significantly improved, and ventricular septum, left ventricular posterior wall, left atrial diameter, left ventricular systolic and end-diastolic diameter were significantly reduced compared with those before surgery. There was no significant difference between gastric sleeve resection and gastric bypass in the improvement of cardiac function and the effect on cardiac morphology. The combined prediction model composed of preoperative body mass index value, decreased body mass index value at 1 year after operation, whether suffering from hypertension, whether the inner diameter of the ascending aorta is widened and other indicators has a good predictive value for the improvement of ejection fraction in bariatric patients at 1 year after operation.

Objective:To systematically evaluate the effect of bariatric and metabolic surgery on bone metabolism in obese patients.Methods:Search terms for the present meta-analysis included "bariatric surgery, metabolic surgery, sleeve gastrectomy, gastric bypass, bone metabolic indicators, bone mineral density", both in English and corresponding Chinese. PubMed, WOS, Cochrane, CNKI, and VIP databases were searched for longitudinal studies from the establishment of the database to September 20, 2022. The data on bone mineral density and bone metabolic markers in obese patients before and after bariatric surgery were extracted. RevMan5.4 and Stata17.0 software were used for Meta-analysis.Results:A total of 8 clinical studies with 420 patients were included. The results of the meta-analysis showed that compared with the preoperative baseline, lumbar spine bone mineral density ( WMD=0.05, 95% CI: -0.00~0.1), femoral neck bone mineral density( WMD=0.10, 95% CI: 0.05-0.15), hip bone mineral density( WMD=0.14, 95% CI: 0.10-0.17), and serum vitamin D 3 ( WMD=-4.87, 95% CI: -6.34--3.40)were decreased, while parathyroid hormone ( WMD=10.04, 95% CI: 5.32-14.76) was elevated after surgery. Conclusions:Current evidence demonstrates that metabolic and bariatric surgery can lead to decreased bone mineral density and impairs in bone metabolic markers early after surgery. Roux-en-Y gastric bypass surgery cause more adverse effects on bone metabolism than sleeve gastrectomy. The results imply that all patients undergoing metabolic and bariatric surgery should be monitored for bone metabolism and routinely take vitamin D and calcium supplements.