Analysis of influencing factors and clinical value of anterior peritoneal reflection for patients with rectal cancer / 中华外科杂志

Objectives: To investigate the factors influencing the height of anterior peritoneal reflection (APR) for patients with rectal cancer, and to analyze the relationship between the APR and the lateral lymph node metastasis. Methods: Clinical data of 432 patients with tumor located within and below APR were retrospectively collected from the rectal cancer database at the Department of General Surgery, Peking Union Medical College Hospital from August 2020 to September 2022. Ninty-eight non-rectal cancer patients were also enrolled as a control group. There were 308 males and 124 females in the tumor group, aged (M(IQR)) 62 (16) years (range: 24 to 85 years) and 53 males and 45 females in the control group, aged 60 (22) years (range: 27 to 87 years). The APR height, pelvis, and tumor-related parameters were measured by MRI. A multifactor linear regression model was established to analyze the dependent correlation factors of APR height. These factors of the two groups were matched by propensity score matching and their APR heights were compared after matching. An ordinal Logistic regression model was established to explore the relationship between APR-related parameters and radiographic lateral lymph node metastasis. Results: The APR height of the tumor group was (98.7±14.4) mm (range: 43.3 to 154.0 mm) and the control group was (95.1±12.7) mm (range: 68.0 to 137.9 mm). Multivariable linear regression revealed that the greater the weight (B=0.519, 95%CI: 0.399 to 0.640, P<0.01), the anterior pelvic depth (B=0.109, 95%CI: 0.005 to 0.213, P=0.039) and the smaller the bi-ischial diameter (B=-0.172, 95%CI:-0.294 to -0.049, P=0.006), the higher the APR height. The tumor group had a higher APR height than the control group after propensity score matching ((98.3±14.2) mm vs. (95.1±12.7) mm, t=-1.992, P=0.047). Ordinal Logistic regression indicated that the longer segment of the tumor invade the nonperitoneal rectum was an independent influencing factor of radiographic lateral lymph node metastasis (OR=1.016, 95%CI: 1.002 to 1.030, P=0.021), while the distance between the anal verge and the tumor was not (OR=0.986, 95%CI: 0.972 to 1.000, P=0.058). Conclusions: The higher the weight, the deeper and narrower the pelvis, the higher the APR height. There is a certain relationship between APR and lateral lymph node metastasis on imaging.

Assessing Liver Function by T1 Maps on Gd-EOB-DTPA-Enhanced MRI for up to 50 Min in Rat Models of Liver Fibrosis: A Longer Hepatobiliary Time Period may Help / 中国医学科学杂志(英文版)

Objectives To investigate whether a longer time period of gadolinium ethoxybenzyl diethylenetriaminepen-taacetic acid (Gd-EOB-DTPA)-enhanced T1 mapping scanning, as well as dynamic contrast-enhanced (DCE) and multiple hepatobiliary phase magnetic resonance imaging (MRI) have the potential to provide information about liver function in rats with liver fibrosis. Methods Forty rats were divided into the carbon tetrachloride-induced hepatic injury groups [carbon tetrachloride for four (

Correlation of Intravoxel Incoherent Motion-derived Parameters with Computer Tomography Perfusion Parameters in Insulinoma / 中国医学科学院学报

To prospectively evaluate the correlation between intravoxel incoherent motion (IVIM)-derived parameters and CT perfusion parameters as well as the pathological grade in insulinoma. A total of 55 patients with suspected insulinoma undergoing IVIM and CT perfusion scans were prospectively enrolled. The images were post-processed to obtain IVIM parameters including apparent diffusion coefficient (ADC),diffusion (D),perfusion correlated diffusion (D*),and f,and CT perfusion parameters including blood flow (BF),blood volume (BV),and permeability (PM). The pathological specimens were stained to obtain pathological parameters including the grading,ki-67 index,and the mitotic count. The IVIM derived parameters of normal pancreas including head,body,and tail as well as that of the pancreatic insulinoma were compared. The correlation between IVIM parameters and CT perfusion parameters as well as the pathological parameters was analyzed. ADC and D values of pancreatic tail were significantly lower than those of the pancreatic head and neck (all 0.05). IVIM parameters differ at different anatomical parts of normal pancreas. IVIM parameters can distinguish normal pancreatic parenchyma from insulinoma. The ADC value is weakly correlated with BF.

Value of Texture Analysis on Gadoxetic Acid-enhanced MR for Detecting Liver Fibrosis in a Rat Model / 中国医学科学杂志(英文版)

Objective To explore the ability of texture analysis of gadoxetic acid-enhanced magnetic resonance imaging (MRI) T1 mapping images, as well as T1-weighted (T1W), T2-weighted (T2W) and apparent diffusion coefficient (ADC) maps for distinguishing between varying degrees of hepatic fibrosis in an experimental rat model.Methods Liver fibrosis in rats was induced by carbon tetrachloride intraperitoneal injection for 4-12 weeks (n=30). In the control group (n=10) normal saline was applied. The MRI protocol contained T2W, diffusion weighted imaging, pre-and post-contrast image series of T1W and T1 mapping images. METAVIR score was used to grade liver fibrosis as normal (F0), mild fibrosis (F1-2), and advanced fibrosis (F3-4). Texture parameters including mean gray-level intensity (Mean), standard deviation (SD), Entropy, mean of positive pixels (MPP), Skewness, and Kurtosis were obtained. Nonparametric Mann-Whitney U test was used to compare the average value of each texture parameter in each sequence for assessing the difference between F0 and F≥1 as well as F0-2 and F3-4. Receiver operating characteristic (ROC) curves were obtained to assess the diagnosing accuracy of the parameters for differentiating no liver fibrosis from liver fibrosis and rats with liver fibrosis grading F0-2 from those with grading F3-4. The area under ROC curve (AUC) was calculated to evaluate the diagnostic efficiency of texture parameters.Results Finally, 20 rats completed MR T1 mapping image scan. The pathologic staging of these 20 rats was no fibrosis (F0, n=6), mild fibrosis (F1-2, n=5) and advanced fibrosis (F3-4, n=9). On pre-contrast T1 mapping image, Entropy was seen to be statistically significant higher in the F≥1 group than that in the F0 group at each spatial scaling factor (SSF) setting (P=0.015, 0.015, 0.015, 0.013, 0.015 and 0.018 respectively to SSF=0, 2, 3, 4, 5, 6), and Mean of the F≥1 rats was statistically significant higher than that of the F0 rats at SSF 4, 5, 6 (P=0.004, 0.006, and 0.013, respectively). Entropy and Mean showed a moderate diagnostic performance in most SSF settings of T1 mapping pre-contrast images for differentiation of normal liver from liver fibrosis.Conclusions Certain texture features of gadoxetic acid-enhanced MR images, especially the Entropy of non-contrast T1 mapping image, was found to be a useful biomarker for the diagnosis of liver fibrosis.

Gadolinium Ethoxybenzyl Diethylene-triamine-pentaacetic-acid-enhanced Magnetic Resonance Imaging Perfusion and Multiple Hepatobiliary-phase Imaging for Quantitative Assessment of Liver Fibrosis in Rat Models / 中国医学科学院学报

Objective To investigate the value of gadolinium ethoxybenzyl diethylene-triamine-pentaacetic-acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) in detecting different stages of liver fibrosis in rats.Methods Rat models of liver fibrosis were induced by carbon tetrachloride intraperitoneal injection for 4 - 12 weeks (n=45). The control group was applied with 0.9% saline (n=15). The MRI protocol contained both dynamic contrast-enhanced sequence (60 continuous scans within 3 minutes,including three pre-contrast measurements) and multiple hepatobiliary-phase acquisitions (every 5 minutes after contrast injection,60 minutes in total). METAVIR score was used to grade liver fibrosis:normal (F0),mild fibrosis (F1 - F2),and advanced fibrosis (F3 - F4). Liver perfusion parameters [transfer constant (K ),extravascular extracellular volume fraction (V),initial area under curve (iAUC),maximum relative enhancement (RE),and time of maximum RE (T)] as well as hepatobiliary-phase parameters [RE at different time point,the decrease of RE (RE=RE - RE),and elimination half-life of RE (T)] were measured and compared with ANOVA analysis and Spearman rank correlation.Results Thirty-one rats completed MRI exams and were then divided into normal (n=10),mild fibrosis (n=10),and advanced fibrosis (n=11) groups. K ,V and iAUC decreased as liver fibrosis progressed (r=-0.631,P=0.002;r=-0.503,P=0.017;r=-0.446,P=0.037). K and V showed significant differences among three groups(F=7.011,P=0.005;F=4.656,P=0.023). K and V were significantly lower in advanced fibrosis group than in normal group (P=0.001,P=0.009). There were statistical significant differences of T,T and RE among groups(F=6.633,P=0.005;F=5.493,P=0.010;F=5.343,P=0.014). Compared to normal and mild fibrosis groups,advanced fibrosis group had significantly longer T and T (P=0.005,P=0.004;P=0.008,P=0.008)and significantly lower RE(P=0.007,P=0.012).Conclusion Perfusion and multi-hepatobiliary-phase parameters such as K ,V,T, T and RE obtained from Gd-EOB-DTPA-enhanced MRI,may be valuable for detecting and staging liver fibrosis.