Duct Diameter Research Articles

The problem of pancreatic fistula development after pancreatic surgery in oncological patients

Pancreaticoduodenal and distal resections are crucial components of pancreatic cancer treatment. Pancreatic fistula is one of the most common complications of these surgeries. The main criterion for the diagnosis of pancreatic fistula is the increase of amylase drain level more than 3 times from the normal blood level. Pancreatic fistulas worsen the long-term results of cancer treatment and increase the risk of bleeding per an erosion of visceral vessels, pancreatitis and peritonitis, as well as increase the duration of hospital stay. Risk factors for pancreatic fistula can be split in two categories: patient-related and procedure-related. The patient-related risk factors are: male sex, age more than 70 years, small or large diameter of the pancreatic duct, epithelial type of the malignancy, comorbidities and a high volume of drainage fluid in the postoperative period. Surgical risk factors are: the severity of intraoperative blood loss, “soft” pancreas, duration of surgery and surgical techniques. The most effective method for fistula prophylaxis is intraoperative risk evaluation with initial pancreatectomy in case of high risk. At the same time, it is possible to use medical glues and pharmacological methods for prevention and treatment of postoperative pancreatic fistulas, but further investigations are required. Thus, prevention and treatment of postoperative pancreatic fistulas is a crucial component of management of patients who undergo surgery for pancreatic malignancies.

Study on the application of self-fixing and self-detachable drainage stent in pancreaticojejunostomy

Objectives: To evaluate the efficacy and safety of the self-fixing and self-detachable drainage stent in pancreaticojejunostomy and to provide supportive data for the follow clinical trials. Methods: This is an experimental research in animals which completed from February 2022 to September 2022. A self-fixing and self-detachable pancreaticojejunostomy drainage stent was designed for Hong's pancreaticojejunostomy technique based on the theory of "fistula healing" in pancreaticojejunostomy. Ten biocompatibility tests were completed in vitro before this study. Twenty-five Bama minipigs were selected and double-ligated in the neck of the pancreas to dilate the distal main pancreatic duct. Twenty-three of them were successfully modelled and divided into three groups by a stratified random method: pancreaticojejunostomy drainage stent group (referred to as stent group) with 11 pigs, pancreatic duct to jejunal mucosa anastomosis group (referred to as manual suture group) with 8 pigs, sham operation group with 4 pigs. The anastomic time,amylase content in postoperative abdominal drainage fluid and the tolerable pressure value of pancreaticojejunostomy were compared between the stent group and the manual suture group. An abdominal X-ray fluoroscopy examination was adopted to detect the detach time of the stent. A postoperative pathological examination was performed to verify the healing time,the type of treatment and the stricture rate of pancreaticojejunostomy. Quantitative data was analyzed by independent sample t-test. The classified data were analyzed by Fisher's exact test. Results: There were no significant differences in the diameter of the pancreatic duct and pancreatic texture,the time of pancreaticojejunostomy,the amylase content in postoperative peritoneal drainage fluid,and the tolerable pressure value of the pancreaticojejunostomy between the stent group and the manual suture group(all P>0.05). Abdominal X-ray fluoroscopy showed that the stents gradually detached and were removed from the body 21 days after operation,and all stents were detached in the follow 3 months after operation. Pancreaticojejunostomy healed 7 days after operation based on fistula formation in the stent group,and 14 days in the manual suture group. The incidence of anastomotic stricture within 35 days after operation was 2/8 in the stent group and 6/8 in the manual suture group (Fisher's exact test: P=0.132). Conclusion: The stent method is safer and simpler than the manual suture method in pancreaticojejunostomy of Bama minipigs, with shorter anastomotic healing time and lower stricture rate.

Effect of endoscopic sphincterotomy and endoscopic papillary balloon dilation endoscopic retrograde cholangiopancreatographies on the sphincter of Oddi.

Endoscopic retrograde cholangiopancreatography (ERCP), with its clinical ad-vantages of less trauma and faster recovery, has become the primary treatment for choledocholithiasis. To investigate the effects of different ERCP procedures on the sphincter of Oddi. The clinical data of 91 patients who underwent ERCP at Yixing Hospital of Traditional Chinese Medicine between February 2018 and February 2021 were analyzed retrospectively. The patients were divided into endoscopic sphincterotomy (EST, n = 24) and endoscopic papillary balloon dilation (EPBD, n = 67) groups. The duration of operation, pancreatic development, pancreatic sphincterotomy, intubation difficulties, stone recurrence, and incidence of reflux cholangitis and cholecystitis were statistically analyzed in patients with a history of choledocholithiasis, pancreatitis, and Oddi sphincter dysfunction in the EST and EPBD groups. Differences in hypertension, diabetes, increased bilirubin, small diameter of the common bile duct, or ampullary diverticulum between the two groups were not significant. Statistically significant differences were observed between the two groups concerning sex and age (< 60 years). Patients with a history of choledocholithiasis, pancreatitis, and Oddi sphincter dysfunction were higher in the EST group than in the EPBD group. The number of cases of pancreatic development, pancreatic duct sphincterotomy, and difficult intubation were higher in the EST group than in the EPBD group. The number of Oddi's sphincter manometries, ERCP surgical outcomes, and guidewires entering the pancreatic duct several times in EST group were lower than those in the EPBD group. The numbers of stone recurrences, reflux cholangitis, and cholecystitis were higher in the EST group than in the EPBD group. In summary, common bile duct stones, pancreatitis history, and multiple guided wire introductions into the pancreatic duct are independent risk factors for EST and EPBD. Based on this evidence, this study can provide actionable insights for clinicians and researchers.

Identifying the risk factors for pancreatic fistula after laparoscopic pancreaticoduodenectomy in patients with pancreatic cancer.

Laparoscopic pancreaticoduodenectomy (LPD) is a surgical procedure for treating pancreatic cancer; however, the risk of complications remains high owing to the wide range of organs involved during the surgery and the difficulty of anastomosis. Pancreatic fistula (PF) is a major complication that not only increases the risk of postoperative infection and abdominal hemorrhage but may also cause multi-organ failure, which is a serious threat to the patient's life. This study hypothesized the risk factors for PF after LPD. To identify the risk factors for PF after laparoscopic pancreatoduodenectomy in patients with pancreatic cancer. We retrospectively analyzed the data of 201 patients admitted to the Fudan University Shanghai Cancer Center between August 2022 and August 2023 who underwent LPD for pancreatic cancer. On the basis of the PF's incidence (grades B and C), patients were categorized into the PF (n = 15) and non-PF groups (n = 186). Differences in general data, preoperative laboratory indicators, and surgery-related factors between the two groups were compared and analyzed using multifactorial logistic regression and receiver-operating characteristic (ROC) curve analyses. The proportions of males, combined hypertension, soft pancreatic texture, and pancreatic duct diameter ≤ 3 mm; surgery time; body mass index (BMI); and amylase (Am) level in the drainage fluid on the first postoperative day (Am > 1069 U/L) were greater in the PF group than in the non-PF group (P < 0.05), whereas the preoperative monocyte count in the PF group was lower than that in the non-PF group (all P < 0.05). The logistic regression analysis revealed that BMI > 24.91 kg/m² [odds ratio (OR) =13.978, 95% confidence interval (CI): 1.886-103.581], hypertension (OR = 8.484, 95%CI: 1.22-58.994), soft pancreatic texture (OR = 42.015, 95%CI: 5.698-309.782), and operation time > 414 min (OR = 15.41, 95%CI: 1.63-145.674) were risk factors for the development of PF after LPD for pancreatic cancer (all P < 0.05). The areas under the ROC curve for BMI, hypertension, soft pancreatic texture, and time prediction of PF surgery were 0.655, 0.661, 0.873, and 0.758, respectively. BMI (> 24.91 kg/m²), hypertension, soft pancreatic texture, and operation time (> 414 min) are considered to be the risk factors for postoperative PF.

Sonographic Determination of the Pancreatic Duct Diameter among Healthy Individuals in Gaborone, Southeast District, Botswana

Sonographic Determination of the Pancreatic Duct Diameter among Healthy Individuals in Gaborone, Southeast District, Botswana

The Revised Kyoto Criteria and Risk of Malignancy Among Patients With Intraductal Papillary Mucinous Neoplasms

Background & AimsThe revised Kyoto guidelines have a new catalog of high-risk stigmata and worrisome features for the risk stratification of intraductal papillary mucinous neoplasms (IPMNs). We aimed to validate the stratification system in terms of short- and long-term risks of pancreatic carcinoma. MethodsWe included 3,336 patients diagnosed with IPMNs in 2000-2021 and examined short-term (≤ 6 months) and long-term risks of pancreatic carcinoma diagnosis. We used the multivariable competing-risks proportional hazards regression model to calculate subdistribution hazard ratios for long-term incidence of pancreatic carcinoma with adjustment for potential confounders. ResultsIn short-term analyses, pancreatic carcinomas were prevalent predominantly in IPMNs with high-risk stigmata (49% vs. 1.3% and 0.05% in IPMNs with worrisome features and no risk factors, respectively). In long-term analyses of worrisome features, the main pancreatic duct diameter of 5-9.9 mm, acute pancreatitis, and IPMN growth rate of 2.5 mm/year were associated with a high incidence with multivariable subdistribution hazard ratios (95% confidence intervals) of 3.46 (2.04-5.89), 5.65 (1.86-17.2), and 3.83 (2.14-6.86), respectively. An increasing number of worrisome features at baseline was associated with a higher prevalence and incidence of pancreatic carcinoma (Ptrend < .001). Patients with 1, 2, and 3-4 worrisome features had multivariable subdistribution hazard ratios (95% confidence intervals) for pancreatic cancer incidence of 1.43 (0.93-2.19), 2.17 (1.17-4.05), and 10.1 (4.20-24.5), respectively (vs. no positive feature). ConclusionsThe revised Kyoto criteria stratify IPMN patients well in terms of the short- and long-term risks of pancreatic carcinoma diagnosis, potentially informing personalized patient management.

Inhibition of Prolactin Affects Epididymal Morphology by Decreasing the Secretion of Estradiol in Cashmere Bucks.

Yanshan Cashmere bucks are seasonal breeding animals and an important national genetic resource. This study aimed to investigate the involvement of prolactin (PRL) in the epididymal function of bucks. Twenty eleven-month-old Cashmere bucks were randomly divided into a control (CON) group and a bromocriptine (BCR, a prolactin inhibitor, 0.06 mg/kg body weight (BW)) treatment group. The experiment was conducted from September to October 2020 in Qinhuangdao City, China, and lasted for 30 days. Blood was collected on the last day before the BCR treatment (day 0) and on the 15th and 30th days after the BCR treatment (days 15 and 30). On the 30th day, all bucks were transported to the local slaughterhouse, where epididymal samples were collected immediately after slaughter. The left epididymis was preserved in 4% paraformaldehyde for histological observation, and the right epididymis was immediately preserved in liquid nitrogen for RNA sequencing (RNA-seq). The results show that the PRL inhibitor reduced the serum PRL and estradiol (E2) concentrations (p < 0.05) and tended to decrease luteinizing hormone (LH) concentrations (p = 0.052) by the 30th day, but no differences (p > 0.05) occurred by either day 0 or 15. There were no differences (p > 0.05) observed in the follicle-stimulating hormone (FSH), testosterone (T), and dihydrotestosterone (DHT) concentrations between the two groups. The PRL receptor (PRLR) protein was mainly located in the cytoplasm and intercellular substance of the epididymal epithelial cells. The PRL inhibitor decreased (p < 0.05) the expression of the PRLR protein in the epididymis. In the BCR group, the height of the epididymal epithelium in the caput and cauda increased, as did the diameter of the epididymal duct in the caput (p < 0.05). However, the diameter of the cauda epididymal duct decreased (p < 0.05). Thereafter, a total of 358 differentially expressed genes (DEGs) were identified in the epididymal tissues, among which 191 were upregulated and 167 were downregulated. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses revealed that ESR2, MAPK10, JUN, ACTL7A, and CALML4 were mainly enriched in the estrogen signaling pathway, steroid binding, calcium ion binding, the GnRH signaling pathway, the cAMP signaling pathway, and the chemical carcinogenesis-reactive oxygen species pathway, which are related to epididymal function. In conclusion, the inhibition of PRL may affect the structure of the epididymis by reducing the expression of the PRLR protein and the secretion of E2. ESR2, MAPK10, JUN, ACTL7A, and CALML4 could be the key genes of PRL in its regulation of epididymal reproductive function.

Efficacy of the omental roll-up technique in pancreaticojejunostomy to prevent postoperative pancreatic fistula after pancreaticoduodenectomy.

Pancreaticoduodenectomy (PD) is being performed more frequently. A pancreaticojejunostomy (PJ) leak is the major determinant of patient outcomes. An omental flap around PJ might improve postoperative outcomes. A prospective randomized controlled trial was planned at PGIMER, Chandigarh. Fifty-eight patients meeting the criteria were included in the study. Group A underwent PD with omental roll-up and group B underwent standard PD. The mean age of patients in group A was 57.1 ± 14.3 years and 51.2 ± 10.7 in group B. Jaundice (p = 0.667), abdominal pain (p = 0.69), and co-morbidities were equal among the groups. The body mass index of patients in group B was higher at 24.3 ± 5.4 kg/m2 (p = 0.03). The common bile duct diameter (12.6 ± 5.3 mm vs. 17.2 ± 10.3 mm, p = 0.13) and the pancreatic duct diameter (4.06 ± 2.01 mm vs. 4.60 ± 2.43 mm, p = 0.91) were comparable. The intraoperative blood loss (mL) was significantly higher in group B (233.33 ± 9.57 vs. 343.33 ± 177.14, p = 0.04). Drain fluid amylase levels on postoperative day (POD) 1 (p = 0.97) and POD3 (p = 0.92) were comparable. The rate of postoperative pancreatic fistula (POPF) grade A (p ≥ 0.99) and grade B (p = 0.54) were comparable. The mean postoperative length of stay among was similar (p = 0.89). An omental wrap can be performed without increase in complexity of the procedure. However, its utility in preventing POPFs and morbidity remains unclear.

Ductus arteriosus diameters in fetuses with early- and late-onset fetal growth restriction.

Fetal growth restriction (FGR) is a common pregnancy complication that can be associated with several adverse perinatal outcomes. One of these negative outcomes is ductus arteriosus, especially in preterm babies. In this study, intrauterine heart function and ductus diameter were evaluated in babies with FGR. Thirty-seven fetuses with FGR were compared with 37 normal-weight fetuses at the same gestational week. In our study, ventricular diameters, aorta, pulmonary artery, ductus arteriosus (DA), aortic arch diameter, and flow traces were examined. In addition, the aorta and aortic isthmus diameters were proportioned to the ductus diameter, and the left ventricular myocardial performance index (MPI) [(ICT + IRT)/ET] was evaluated. There was no difference in DA diameters between the patient and control groups. The intragroup comparison of the cases with early- and late-onset FGR revealed no statistically significant difference between DA diameters. However, the ratios of the aortic annulus diameter/ductus diameter (AOD/DAD) and aortic isthmus diameter/ductus diameter (AID/DAD) were significantly lower in early-onset FGR because the diameter of the DA was greater. In addition, the mod-MPI values were higher in the patient group. In our study, although the ductal diameters did not change significantly in the patient group, the ductal diameter was greater in the early-onset intrauterine growth restriction (FGR) group compared with other cardiac measurements. The mod-MPI value, a cardiac function indicator, was higher in fetuses with FGR. These findings may be useful for evaluating postnatal cardiac functions in FGR.

A Comparison of Preoperative Predictive Scoring Systems for Postoperative Pancreatic Fistula after Pancreaticoduodenectomy Based on a Single-Center Analysis.

Background: Postoperative pancreatic fistula (POPF) after pancreaticoduodenectomy (PD) is associated with major postoperative morbidity and mortality. Several scoring systems have been described to stratify patients into risk groups according to the risk of POPF. The aim of this study was to compare scoring systems in patients who underwent a PD. Methods: A total of 196 patients undergoing PD from July 2019 to June 2022 were identified from a prospectively maintained database of the University Hospital Ghent. After performing a literature search, four validated, solely preoperative risk scores and the intraoperative Fistula Risk Score (FRS) were included in our analysis. Furthermore, we eliminated the variable blood loss (BL) from the FRS and created an additional score. Univariate and multivariate analyses were performed for all risk factors, followed by a ROC analysis for the six scoring systems. Results: All scores showed strong prognostic stratification for developing POPF (p < 0.001). FRS showed the best predictive accuracy in general (AUC 0.862). FRS without BL presented the best prognostic value of the scores that included solely preoperative variables (AUC 0.783). Soft pancreatic texture, male gender, and diameter of the Wirsung duct were independent prognostic factors on multivariate analysis. Conclusions: Although all predictive scoring systems stratify patients accurately by risk of POPF, preoperative risk stratification could improve clinical decision-making and implement preventive strategies for high-risk patients. Therefore, the preoperative use of the FRS without BL is a potential alternative.

Open-Y technique for the internal mammary vein in the free abdominal flap of unilateral breast reconstruction

BackgroundIn microvascular breast reconstruction, the internal mammary vein (IMV) has emerged as the most common recipient vein. The open-Y technique can increase the vessel diameter via the bifurcation site. This study aims to investigate the open-Y technique for IMV. MethodsThe characteristics and details of the operative procedure in patients who had undergone unilateral breast reconstruction with and without the open-Y approach for the free abdominal flap were compared. Differences in IMV anastomosis site (the bifurcation of the main duct or that of the perforator branch) were also compared in patients with the open-Y technique. The open-Y technique was performed on the IMV side. ResultsThe open-Y and conventional groups included 127 and 62 patients respectively. The main duct diameter of IMV was significantly smaller (median 2.5 vs. 3.0mm, P < 0.001), and the rate of right-sided anastomosis (47.2 vs. 82.3%, P < 0.001) was significantly lower in the open-Y group. When comparing the main duct and perforator groups, the branch diameter (1.8 vs. 1.0mm, P < 0.001) and the diameter after the open-Y technique (5.0 vs. 3.9mm, P < 0.001) were significantly higher, and the angle of bifurcation (45° vs. 60°, P = 0.007) was significantly lower in the main duct group. ConclusionsGiven a small venous diameter, the open-Y technique is superior, especially for left-sided breast reconstruction. Owing to the lower angle of bifurcation and large diameter, the open-Y technique at the main duct bifurcation of IMV causes less turbulence in the blood flow. Take home messageThe open-Y technique is especially effective for left-sided breast reconstruction. Considering the lower angle of bifurcation and large diameter, the open-Y technique at the main duct bifurcation of the internal mammary vein causes less turbulence in the blood flow.

Ultrasound analysis of cervical thoracic duct for patients with constrictive pericarditis and chylothorax.

To analyze ultrasound features of cervical thoracic duct for patients with constrictive pericarditis and chylothorax. Patients were retrospectively assessed. The patients were divided into a non-pleural effusion (PE) group (n = 54), a chylothorax group (n = 23), and non-chylothorax group (n = 28). Conventional ultrasound was used to obtain the maximum inner diameter and collapse of the inferior vena cava, the inner diameter of left cervical thoracic duct, and the frequency of opening of the valve at the end of the left thoracic duct. Contrast ultrasonography was used to score the reverse flow of the thoracic tube. The percentage of PE was 48.5%, and the percentage of chylothorax was 21.9%. The three groups had significant differences in five parameters. The inner diameter of left cervical thoracic duct was correlated with the degree of central venous pressure. Contrast ultrasonography was effective in quantitative assessment of the degree of intravenous-thoracic cord reverse flow which correlated with all parameters of central venous pressure. Thoracic duct dilation and regurgitation secondary to central venous pressure can lead to chyloreflux disorder and may be the mechanism of chylothorax occurrence in constrictive pericarditis.

Association of preoperative CT-scan features and clinically relevant postoperative pancreatic fistula after pancreaticoduodenectomy: a meta-analysis.

Clinically relevant postoperative pancreatic fistula (CR-POPF) is a significant complication after pancreaticoduodenectomy. CR-POPF is associated with various adverse outcomes, including high mortality rates. Identifying complication predictors for CR-POPF, such as preoperative CT scan features, including pancreatic attenuation index (PAI) and pancreatic duct diameter (PDD), is critical. This systematic review and meta-analysis consolidate existing literature to assess the impact of these variables on CR-POPF risk. Our comprehensive search, conducted in May 2023, covered PubMed, Scopus, Embase, and Web of Science databases. Inclusion criteria encompassed peer-reviewed cohort studies on pancreaticoduodenectomy, focusing on preoperative CT scan data. Case reports, case series, and studies reporting distal pancreatectomy were excluded. The quality assessment of included articles was done using New-Castle Ottawa Scale for cohort studies. Statistical analysis was carried out using Review Manager 5. This study was registered at the International Prospective Register of Systematic Reviews database (PROSPERO) on 12 May 2023 (registration number: CRD42023414139). We conducted a detailed analysis of 38 studies with 7393 participants. The overall incidence of CR-POPF was 24%. Multiple linear regression analyses revealed that PDD and pancreatic parenchymal thickness were significantly associated with CR-POPF. Our systematic review and meta-analysis shed light on CT scan findings for predicting CR-POPF after Whipple surgery. Age, PDD, and pancreatic parenchymal thickness significantly correlate with CR-POPF.

Minimally Invasive Common Bile Duct Stone Management in Gastric Bypass Patients: Laparoscopic Common Bile Duct Exploration with Disposable Bronchoscope.

Bariatric surgery patients may develop common bile duct stones, and the alterations in their anatomy present challenges in treating this condition. Methods such as laparoscopic bile duct exploration is impractical in many healthcare facilities, due to the absence of a choledochoscope. This study assesses the feasibility of laparoscopic exploration of the common bile duct using a disposable bronchoscope in these individuals. The study involved 32 participants who had undergone gastric bypass surgery. These participants presented with both bile duct stones and bile ducts exceeding 8mm in diameter, diagnosed through either MRCP or cholangiography conducted during the surgery. Stone extraction was carried out through either choledotomy or transcystic routes using a disposable bronchoscope and endoscopic baskets. The patients' ages ranged from 27 to 66years, with a mean bile duct diameter of 11.6mm (SD 3.1mm). A 100% stone clearance rate was achieved for all patients. None of the patients required conversion to open surgery. No T-tubes were placed. One patient developed biloma and intra-abdominal abscesses, which were successfully treated with a percutaneous drain over the course of a week. No mortalities were recorded during the course of this study. Our study results demonstrate that laparoscopic bile duct exploration is both feasible and safe in patients who have undergone gastric bypass surgery. The utilization of a disposable bronchoscope emerges as a practical and cost-effective alternative to a choledochoscope in this procedure.

Prediction for post-ERCP pancreatitis in non-elderly patients with common bile duct stones: a cross-sectional study at a major Chinese tertiary hospital (2015–2023)

BackgroundPost-ERCP pancreatitis is one of the most common adverse events in ERCP-related procedures. The purpose of this study is to construct an online model to predict the risk of post-ERCP pancreatitis in non-elderly patients with common bile duct stones through screening of relevant clinical parameters.MethodsA total of 919 cases were selected from 7154 cases from a major Chinese tertiary hospital. Multivariable logistic regression model was fitted using the variables selected by the LASSO regression from 28 potential predictor variables. The internal and external validation was assessed by evaluating the receiver operating characteristic curve and the area under curve. Restricted cubic spline modelling was used to explore non-linear associations. The interactive Web application developed for risk prediction was built using the R “shiny” package.ResultsThe incidence of post-ERCP pancreatitis was 5.22% (48/919) and significantly higher in non-elderly patients with female, high blood pressure, the history of pancreatitis, difficult intubation, endoscopic sphincterotomy, lower alkaline phosphatase and smaller diameter of common bile duct. The predictive performance in the test and external validation set was 0.915 (95% CI, 0.858–0.972) and 0.838 (95% CI, 0.689–0.986), respectively. The multivariate restricted cubic spline results showed that the incidence of pancreatitis was increased at 33–50 years old, neutrophil percentage > 58.90%, hemoglobin > 131 g/L, platelet < 203.04 or > 241.40 × 109/L, total bilirubin > 18.39 umol / L, aspartate amino transferase < 36.56 IU / L, alkaline phosphatase < 124.92 IU / L, Albumin < 42.21 g / L and common bile duct diameter between 7.25 and 10.02 mm. In addition, a web server was developed that supports query for immediate PEP risk.ConclusionThe visualized networked version of the above model is able to most accurately predict the risk of PEP in non-elderly patients with choledocholithiasis and allows clinicians to assess the risk of PEP in real time and provide preventive treatment measures as early as possible.

Experimental investigation of effect of different configurations of semi-circular or half-round ribs on heat transfer enhancement in a rectangular duct

This research study investigated the impact of various configurations of semi-circular or half-round ribs on the thermal performance and frictional factor characteristics of a rectangular duct. During this research study, the ribs were provided on the inner surface of the test section’s bottom wall. Six distinct configurations of semi-circular ribs varying from continuous to hybrid arrangement were used. The range of Reynolds number was varied from 13,500 to 34,800; while the ratio of rib pitch to rib height (P/e ratio) was kept constant at 8. The ratio of the height of rib to hydraulic diameter of duct (also known as blockage ratio) was kept at 0.114. The results of experimental investigation showed that the Nusselt number ratio obtained was ranging from 1.36 to 2.74, while the friction factor ratio ranges from 1.70 to 4.51. The overall enhancement ratio for all configurations obtained was in the range of 1.06–1.80 times to that of plain duct. Among all rib configurations, the hybrid rib configuration showed superior ratio of Nusselt number and intermediate increase in ratio of friction factor as compared to all the other rib configurations. Hybrid rib configuration showed overall enhancement ratio values ranging from 1.45 to 1.80 times as compared to that of plain duct (duct without ribs) within the specified range of Reynolds number. The results of study showed that the hybrid configuration of semi-circular ribs exhibited superior overall thermal enhancement as compared to that of remaining tested rib configurations.

Magnetic resonance imaging features and classification of intraductal papillary neoplasm of the bile duct

Objective: To explore the magnetic resonance imaging (MRI) features and classification of intraductal papillary neoplasm of the bile duct (IPNB). Methods: Data from 90 patients with intraductal papillary neoplasm of the bile duct confirmed pathologically between June 2010 and January 2023 were retrospectively analyzed. The image analysis included the shape and location of the tumor, whether bile ducts had dilatation and the degree of dilation, whether there was a history of liver disease, whether there was a history of schistosomiasis, whether there was cancerous transformation, whether there were concurrent bile duct stones, whether there was hepatic lobe atrophy, whether there was hilar or abdominal lymph node enlargement, whether there was invasion of the bile duct wall, whether there was invasion of surrounding blood vessels, whether the tumor appears on T1-and T2 weighted imaging (T(1)WI and T(2)WI), whether the diffusion was limited, whether there was concurrent bleeding, enhancement rate, and whether there was abdominal fluid accumulation. Intraductal papillary neoplasms of the bile duct were divided into four types according to the morphological classification standards: type I (local bile duct dilation), type II (cystic), type III (free tumor), and type IV (dilated bile duct). The differences in the clinical and MRI features of the four groups of lesions were analyzed. Statistical analysis was performed with a t-test, an analysis of variance, and an χ(2)-test according to the different data. Results: Among the 90 cases with hepatic IPNB, there were 31 cases of type I, 15 cases of type II, 16 cases of type III, and 28 cases of type IV, 41 cases of liver left lobe, 11 cases of right and left lobe liver span, 7 cases of liver right lobes, 2 cases of liver caudate lobe, and 13 cases of hepatic hilar. There were statistically significant differences between the four groups (P < 0.05) in terms of age, clinical symptoms, direct bilirubin, γ-glutamyltransferase, whether they were cancerous, whether they were combined with bile duct stones, whether the liver lobes were atrophying, whether there was limited diffusion, intrahepatic bile duct diameter, and common bile duct diameter. However, there were no statistically significant differences among the four groups in gender, location, carbohydrate antigen 19-9, history of liver disease, history of schistosomiasis, carcinoembryonic antigen, alanine aminotransferase, aspartate aminotransferase, total bilirubin, whether hemorrhage was associated, lesion enhancement rate, whether the hilar/retroperitoneal lymph node was enlarged, whether the bile duct wall was invaded, whether blood vessels were invaded, and whether abdominal fluid was accumulated (P > 0.05). Conclusion: MRI manifestations have certain features for different types of intraductal papillary neoplasm of the bile duct tumors; hence, MRI aids in the diagnosis and differential diagnosis of this disease.

Key postnatal magnetic resonance characteristics for differentiating cystic biliary atresia from choledochal cyst.

To analyze the ability of magnetic resonance (MR) to identify cystic biliary atresia (CBA) and choledochal cyst (CC). Infants (≤ 1 year old) who were diagnosed with CBA or CC type I/IV from January 2010 to July 2023 were retrospectively reviewed. Imaging characteristics on MR were compared between the CBA and CC groups. Binary logistic regression and the area under the receiver operating characteristic curve (AUC) were analyzed for the identification of CBA. Sixty-three patients with CBA (median age, 30 days) and 172 patients with CC (median age, 60 days) were included. Gallbladder (GB) wall thickness (cutoff, 1.2 mm) showed 98.4% sensitivity and 100% specificity (AUC, 0.998). MR-triangular cord thickness (MR-TCT) (cutoff, 4.1 mm) showed 100% sensitivity and 95.9% specificity (AUC, 0.986). The bile duct loop visualization showed 96.8% sensitivity and 100% specificity (AUC, 0.984). Proximal bile duct (PBD) diameter (cutoff, 1.3 mm) showed 92.1% sensitivity and 95.3% specificity (AUC, 0.977). Cyst wall thickness (cutoff, 1 mm) showed 77.8% sensitivity and 95.3% specificity (AUC, 0.942). The combination of GB wall thickness > 1.2 mm and MR-TCT > 4.1 mm, GB wall thickness > 1.2 mm and loop visualization, GB wall thickness > 1.2 mm, and cyst wall thickness > 1 mm showed 100% sensitivity and 100% specificity (AUC, 1.000). Imaging characteristics on MR might be used to identify CBA and CC, and the combination of GB wall thickness and MR-TCT, or loop visualization, or cyst wall thickness, has a perfect diagnostic value. Early and accurate differentiation of CBA and CC is essential, but current methods rely on inherently subjective ultrasound. Biliary features on MRI allow for an objective, accurate diagnosis.

Comparison between Endoscopic Ultrasound-Guided Antegrade and Transluminal Stent Implantation in Distal Malignant Biliary Obstruction after Failed ERCP.

Distal malignant biliary obstruction (DMBO) can result in obstructive jaundice. Endoscopic ultrasound- (EUS-) guided biliary drainage (EUS-BD) has been an alternative for DMBO after failed ERCP. To compare the efficacy and safety between antegrade and transluminal approaches in patients with unresectable DMBO when ERCP failed. Patients with DMBO leading to obstructive jaundice after failed ERCP were enrolled in this study. We retrospectively evaluated the safety and efficacy between EUS-guided transluminal stenting (TLS group) and antegrade stenting (AGS group). 82 patients were enrolled, of which 45 patients were in TLS group and 37 in AGS group. There were no statistical differences in the malignancy type, baseline common bile duct diameter, total bilirubin level, reason for EUS-BD, and history of biliary drainage between TLS and AGS groups. The technical success rate was statistically higher in TLS group than in AGS group (97.8 vs. 81.1%, P = 0.031). There were no statistical differences in clinical success rate, procedure-related adverse events, stent migration rate, stent dysfunction rate, reintervention rate, and overall patient survival time between TLS and AGS groups. The median time to stent dysfunction or patient death in TLS and AGS groups was 53 and 81 days, respectively (P = 0.017). Although AGS had a lower technical success rate than TLS, it was superior to TLS in stent patency in patients with DMBO.

Variability of Silver Fir Needle (Abies alba Mill.) Anatomical Features in the Southeast Europe Natural Populations.

The survival of marginal/peripheral silver fir (Abies alba Mill.) populations in the broader region of Southeast Europe is endangered due to climate change and population decline. This study aimed to determine the level and pattern of variability for the anatomical traits of needles and the possibility of linking the pattern of phenotypic variability with environmental factors. In most of the analyzed needle traits, the statistically significant variability between populations was determined. According to the results of the multivariate principal component analysis, it is evident that the populations are distinct from each other, in three groups. The climatic factors Hargreaves reference evaporation, mean annual temperature, and growing degree-days, were statistically significantly correlated. The altitude and heating degree-days are statistically significantly correlated with the following three environmental factors: Hargreaves reference evaporation, mean annual temperature and growing degree-days, but negatively with others. The paper's findings indicate significant moderate and high correlations between the anatomical traits of the needles' central bundle diameter with the resin duct diameter, the distance between the vascular bundle and the resin duct and the epidermis thickness with cuticle, the resin duct diameter with the distance between the vascular bundle and the resin duct and the epidermis thickness with cuticle, as well as the distance between the vascular bundle and the resin duct with the hypodermis height and the epidermis thickness with cuticle. The results of agglomerative hierarchical clustering analysis, performed for anatomical and climatic traits, confirmed the existence of three groups of tested populations according to the altitude gradient. Research results provide knowledge on the diversity and structure of Abies alba populations of Southeast Europe, important for further research and guidelines for the species' conservation and genetic variability preservation in the southern marginal distribution area and keeping in line with climate change projections.