Gallbladder function and dynamics of bile flow in asymptomatic gallstone disease

Association between history of cholecystectomy and risk of gastric cancer: a meta-analysis of epidemiological studies

PURPOSE

Evidence from previous studies on the association between cholecystectomy and risk of gastric cancer are still inconsistent. We aimed at conducting a meta-analysis of epidemiological studies to evaluate this association.

METHODS

Researchers searched three databases (PubMed, Embase and Web of Science) through January 2021 for eligible studies. Relative risks (RRs) and 95% CIs in each included studies were pooled by random-effects models. Patients and the public were not involved in our study.

RESULTS

Eight studies were identified. Four studies reported significantly positive association between history of cholecystectomy and risk of gastric cancer, and the remaining studies reported null association. The pooled RR of these eight studies showed that a history of cholecystectomy was associated with a 11% higher risk of gastric cancer (pooled RR=1.11, 95% CI: 1.03 to 1.20). Moderate heterogeneity across the studies was detected (p=0.117, I2=37.8%). The pooled RRs were 1.12 (95% CI: 1.01 to 1.24) for five cohort studies and 0.95 (95% CI: 0.66 to 1.38) for three case-control studies. Compared with the risk in Europe and the USA, the pooled RR was higher for two studies conducted in Asia. Six studies were assessed as high-quality studies with the pooled RR of 1.12 (95% CI: 1.02 to 1.23). The pooled results were robust by sensitivity analyses, and no indication of publication bias was detected.

CONCLUSION

This meta-analysis suggests that a history of cholecystectomy may be associated with an increased risk of gastric cancer.

Bile Flow Dynamics in Patients with Cholelithiasis: An Evaluation with Cine-Dynamic Magnetic Resonance Cholangiopancreatography Using a Spatially Selective Inversion-Recovery Pulse

Background: A variety of pathophysiological changes in the biliary system occur in patients with cholelithiasis, but the changes in the bile flow dynamics in those patients remain unclear. The purpose of this study was to elucidate the changes in the bile flow dynamics in patients with cholelithiasis using cine-dynamic magnetic resonance cholangiopancreatography (MRCP) with a spatially selective inversion-recovery (IR) pulse. Methods: We retrospectively examined 25 patients with gallstones (gallstone group) and 69 patients without gallstones (non-gallstone group) who underwent abdominal MRI, including in- and opposed-phase T1-weighted images and cine-dynamic MRCP with a spatially selective IR pulse. The frequency and secretion grade of the antegrade and reverse flow of the bile on the cine dynamic MRCP images and the signal intensity ratio (SIR) of the gallbladder in the in- and opposed-phase T1-weighted images were evaluated. Results: The frequency and mean secretion grade of the antegrade bile flow were significantly higher in the gallstone group than in the non-gallstone group (p = 0.011 and p = 0.003), while no significant differences in those values of the reverse bile flow were found between the two groups. The SIR of the gallbladder in the T1-weighted gradient-echo in-phase images was significantly lower in the gallstone group than in the non-gallstone group (p = 0.004). Conclusions: Cine-dynamic MRCP with a spatially selective IR pulse can noninvasively visualize changes in the bile flow dynamics of patients with gallstones.

Patient-specific fluid-structure interaction model of bile flow: comparison between 1-way and 2-way algorithms

Gallbladder disease is one of the most spread pathologies in the world. Despite the number of operations dealing with biliary surgery increases, the number of postoperative complications is also high. The aim of this study is to show the influence of the biliary system pathology on bile flow character and to numerically assess the effect of surgical operation (cholecystectomy) on the fluid dynamics in the extrahepatic biliary tree, and also to reveal the difference between 1-way and 2-way FSI algorithms on the results. Moreover, the bile viscosity and biliary tree geometry influence on the choledynamics were evaluated. Bile velocity, pressure, wall shear stress (WSS), displacements and von Mises stress distributions in the extrahepatic biliary tree are presented, and comparison is made between a healthy and a lithogenic bile. The patient-specific biliary tree model is created using magnetic resonance imaging (MRI) and imported in a commercial finite element analysis software. It is found that in the case of lithogenic bile, velocities have lower magnitude while pressures are higher. Furthermore, stress analysis of the bile ducts shows that the WSS distribution is found mostly prevailing in the common hepatic duct and common bile duct areas. It is shown that when it is necessary to evaluate the bile flow dynamics in urgent medical situations, 1-way analysis is acceptable. Nevertheless, 2-way FSI provides more accurate data, if necessary to evaluate the stress-strain state of bile ducts. The proposed model can be applied to medical practice to reduce the number of post-operative complications.

Constitutive law of healthy gallbladder walls in passive state with damage effect

Biomechanical properties of human gallbladder (GB) wall in passive state can be valuable to diagnosis of GB diseases. In the article, an approach for identifying damage effect in GB walls during uniaxial tensile test was proposed and a strain energy function with the damage effect was devised as a constitutive law phenomenologically. Scalar damage variables were introduced respectively into the matrix and two families of fibres to assess the damage degree in GB walls. The parameters in the constitutive law with the damage effect were determined with a custom MATLAB code based on two sets of existing uniaxial tensile test data on human and porcine GB walls in passive state. It turned out that the uniaxial tensile test data for GB walls could not be fitted properly by using the existing strain energy function without the damage effect, but could be done by means of the proposed strain energy function with the damage effect involved. The stresses and Young moduli developed in two families of fibres were more than thousands higher than the stresses and Young's moduli in the matrix. According to the damage variables estimated, the damage effect occurred in two families of fibres only. Once the damage occurs, the value of the strain energy function will decrease. The proposed constitutive laws are meaningful for finite element analysis on human GB walls.

Gallbladder function predicts subsequent biliary complications in patients with common bile duct stones after endoscopic treatment?

BACKGROUND

In patients with common bile duct stones (CBDS) and intact gallbladder, further management for the gallbladder after the CBDS clearance is still controversial. The relationship between gallbladder motility and the biliary complications were seldom discussed. Our study is to predict the subsequent biliary complications by gallbladder function test using fatty meal sonography (FMS) in patients with CBDS who had been treated by endoscopic retrograde cholangiopancreatography (ERCP).

METHODS

Patients with an intact gallbladder and CBDS after endoscopic clearance of bile duct were enrolled. Patients received a fatty meal sonography after liver function returned to normal. The fasting volume, residual volume, and gallbladder ejection fraction (GBEF) in FMS were measured. Relationships of patients' characteristics, gallbladder function and recurrent biliary complication were analyzed.

RESULTS

From 2011 to 2014, 118 patients were enrolled; 86 patients had calculus gallbladders, and 32 patients had acalculous gallbladders. After a mean follow- up of 33 months, 23 patients had recurrent biliary complications. Among 86 patients with calculus gallbladder, 15 patients had spontaneous clearance of gallbladder stones; 14 patients received cholecystectomy due to acute cholecystitis or recurrent colic pain with smooth postoperative courses. In the follow up period, six patients died of non-biliary causes. The GBEF is significant reduced in most patients with a calculus gallbladder in spite of stone color. Calculus gallbladder, alcohol drinking and more than one sessions of initial endoscopic treatment were found to be the risk factors of recurrent biliary complication.

CONCLUSIONS

Gallbladder motility function was poorer in patients with a calculus gallbladder, but it cannot predict the recurrent biliary complication. Since spontaneous clearance of gallbladder stone may occur, wait and see policy of gallbladder management after endoscopic treatment of CBDS is appropriate, but regular follow- up in those patients with risk factors for recurrence is necessary.

Change in biliary motility in rats with severe acute pancreatitis and its effect

AIM: To observe the change in biliary motility in rats with severe acute pancreatitis and study its effect.

METHODS: Severe acute pancreatitis was induced in 28 male Sprague-Dawley rats by injection of sodium taurocholate into the pancreatobiliary duct. These rats were randomly divided into an experiment group (n = 14) and a control group (n = 14). Another 14 male SD rats injected with saline served as a sham operation group (SO group, n = 14). The experiment group was pretreated by intraperitoneal injection of anisodamine at 20 mg/kg. The control group was pretreated with saline. Twenty-four hours after operation, quantitative ^99mTc-EHIDA hepatobiliary dynamic imaging was performed in each group. Plasma levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and endotoxin (ET) were detected, and the levels of cholecystokinin 8 (CCK8) in plasma, gallbladder and duodenal tissues were also measured. Abdominal viscera bacterial translocation rates were compared among these groups.

RESULTS: In comparison with the SO group and experiment group, a significant delay in duodenal appearance time (DAT) was noted in the control group (56.73 s ± 12.34 s vs 48.44 s ± 11.12 s, 29.52 s ± 11.83 s). A lower level of CCK8 in duodenal tissue was found in the control group than in the SO group and experiment group (5.24 pg/mL ± 0.56 pg/mL vs 5.81 pg/mL ± 0.45 pg/mL, 6.25 pg/mL ± 0.53 pg/mL). The levels of TNF-α, IL-1β, and ET were significantly higher in the control group and experiment group at 24 h after operation than in the SO group (P < 0.05 for all). The levels of TNF-α and ET were significantly lower in the experiment group than in the control group (ET: 0.148 EU/mL ± 0.032 EU/mL vs 0.320 EU/mL ± 0026 EU/mL, P = 0.040; TNF-α: 89.24 pg/mL ± 34.45 pg/mL vs 123.18 pg/mL ± 41.24 pg/mL, P = 0.049). The abdominal viscera bacterial translocation rate was significantly higher in the control group than in the other two groups (0.714% vs 0.573%, 0.143%, P < 0.05).

CONCLUSION: The inhibition of biliary motility was observed in rats with acute pancreatitis, and the change in biliary motility may promote viscera bacterial translocation.

Standardization of "In-House fatty meal" methodology for cholescintigraphy

AIM

This study was aimed at standardizing the "In-House fatty meal" methodology in cholescintigraphy and to determine gall bladder ejection fraction (GBEF) with this standardized meal.

MATERIALS AND METHODS

This is a prospective case-control study where 61 patients having right upper quadrant pain and postprandial bloating and 59 healthy volunteers were included. They underwent (99m)Tc-mebrofenin fatty meal cholescintigraphy following a standard protocol. Dynamic acquisitions over 120 min were done, with a fatty meal being given between 45- and 60-min. Gallbladder emptying kinetics was studied by assessing the time activity curves and calculation of GBEFs were made at 30-min, 45-min, and at 60-min and assessed.

RESULTS

The GBEF at 30-min was 74.42% ± 8.26% (mean ± standard deviation), at 45-min was 82.61% ± 6.5%, and at 60-min was 89.37% ± 4.48% in the volunteer group. The lower limit of GBEF in volunteers at 30-min was 58%, 45-min was 69%, and at 60-min was 81%. Receiver operating characteristic (ROC) analysis showed that 30-min GBEF provided the best separation between healthy and diseased subjects with an area under curve of 0.952 (95% confidence interval = 0.914-0.989). The lower limit of GBEF at 30-min was 58%.

CONCLUSIONS

An in-House standard fatty meal could be a reproducible alternative to cholecystokinin as it is well-tolerated. Based on ROC curve analysis, we propose that 30-min GBEF provides good separation between healthy and diseased people with this in-House fatty meal. Hence, dynamic acquisitions beyond 30-min postingestion of the fatty meal may not be warranted.

A new exploration for gallbladder polyps: gallbladder polypectomy by endolap technique

Abstract Gallbladder polyps are most commonly treated with cholecystectomy, which is associated with various complications. For benign disease, preserving the gallbladder is preferable. Since 1994, we have been exploring percutaneous polypectomy and have recently developed an improved new technique. This study reports a new endoscopic-laparoscopic (Endolap) technique for the removal of polyps and the preservation of the gallbladder. Nine Chinese mini-pigs were used to observe mucosal regeneration. Microwaves of 50-70 mA for 9 seconds were safe, and the gallbladder mucosa of pigs recovered to nearly normal 2 weeks later. In the clinical cases, 60 patients with gallbladder polyps were studied. With the patient under general anesthesia, each polyp stem was coagulated, and then the polyp was removed. All procedures were successful at between 60 and 135 minutes. The success rate was 93.33% (56/60). A retrospective analysis was conducted to assess the recovery of gallbladder function. All patients were followed up and symptom-free, without recurrence of the polyps; 3 months after the operation, the volume and contraction of the gallbladder recovered to preoperative levels. Thus the Endolap technique is reliable for removing benign gallbladder polyps and is applicable to a wider range of clinical situations than percutaneous polypectomy.

Assessment of physiologic bile flow in the extrahepatic bile duct with cine-dynamic MR cholangiopancreatography and a spatially selective inversion-recovery pulse

PURPOSE

To determine the feasibility of directly and noninvasively visualizing physiologic bile flow in the extrahepatic bile duct by means of nonpharmacologic cine-dynamic magnetic resonance (MR) cholangiopancreatography with a spatially selective inversion-recovery (IR) pulse and assess the flow dynamic pattern of bile in the extrahepatic bile duct.

MATERIALS AND METHODS

The institutional review board approved this retrospective study and waived the need for informed consent. Thirty-five patients without known pancreatobiliary diseases and 11 patients with dilatation of the extrahepatic bile duct were included. Cine-dynamic MR cholangiopancreatography with a spatially selective IR pulse was performed by imaging every 15 seconds over a 5-minute interval (20 images acquired total). The images were evaluated for the visualization of bile flow, the frequency that bile flow was observed in the extrahepatic bile duct, and the distance the bile moved within the area of the IR pulse. Statistical analysis was performed by using Spearman rank correlation coefficient and Mann-Whitney U tests.

RESULTS

Antegrade bile flow was observed in 29 of 35 patients (83%) in the nondilated group. Bile flow was observed much more frequently in the nondilated group than in the dilated group (4.4 times vs 1.8 times, P = .029). The distance that bile moved forward within the area of the IR pulse was significantly greater in the nondilated group than in the dilated group (mean grade, 0.44 vs 0.14; P = .033), suggesting stagnation or slowdown of antegrade bile flow in patients with biliary dilatation. Reversed bile flow was also observed in 26 of 35 patients (74%) in the nondilated group without biliary diseases.

CONCLUSION

Nonpharmacologic cine-dynamic MR cholangiopancreatography with a spatially selective IR pulse allows direct and noninvasive visualization of bile flow in the extrahepatic bile duct, demonstrating that reversed bile flow is a physiologic phenomenon.

Impact of airplane cabin pressure on biliary motility in rabbits

AIM: To observe the effect of the change in barometric pressure on biliary motility by using a hypobaric chamber to simulate a civil aircraft in flight.

METHODS: Forty-two rabbits were randomly divided into a control group (n = 14), a Ta group (n = 14, hypobaric exposure in a hypobaric chamber 3 times in 3 d) and a Tb group (n = 14, hypobaric exposure in a hypobaric chamber 7 times in 7 d). The level of cholecystokinin 8 (CCK8) was measured in the duodenal tissue and plasma. The expression of CCK-A receptor (CCK-AR) mRNA in gallbladder tissues was detected by RT-PCR. Quantitative analysis of 99mTc-EHIDA hepatobiliary dynamic imaging was made in each group.

RESULTS: Compared to the control group, the Ta group had lower levels of CCK8 both in duodenal tissue and plasma (Ta group vs C group, 5.24 pg/mL ± 0.56 pg/mL vs 6.25 pg/mL ± 0.53 pg/mL in duodenal tissue, P < 0.05; 3.59 pg/mL ± 0.20 pg/mL vs 4.61 pg/mL ± 0.10 pg/mL in plasma, P < 0.05) and a significant delay in duodenal appearance time (Ta group vs C group, 114.73 s ± 13.34 s vs 79.52 s ± 10.83 s, P < 0.05). Besides a delay in DAT and lower level of CCK8, decreased expression of CCK-A receptor mRNA was found in gallbladder tissues in the Tb group compared to the control group and Ta group (CCK-AR/β-actin: Tb group vs C group: 0.56 ± 0.21 vs 0.82 ± 0.16, P < 0.05; Tb group vs Ta group: 0.56 ± 0.21 vs 0.75 ± 0.29, P < 0.05).

CONCLUSION: Barometric pressure change in a civil aircraft in flight shows some inhibitory effects on biliary motility.

Concept of the pathogenesis and treatment of cholelithiasis

Gallstone disease (GD) is a chronic recurrent hepatobiliary disease, the basis for which is the impaired metabolism of cholesterol, bilirubin and bile acids, which is characterized by the formation of gallstones in the hepatic bile duct, common bile duct, or gallbladder. GD is one of the most prevalent gastrointestinal diseases with a substantial burden to health care systems. GD can result in serious outcomes, such as acute gallstone pancreatitis and gallbladder cancer. The epidemiology, pathogenesis and treatment of GD are discussed in this review. The prevalence of GD varies widely by region. The prevalence of gallstone disease has increased in recent years. This is connected with a change in lifestyle: reduction of motor activity, reduction of the physical load and changes to diets. One of the important benefits of early screening for gallstone disease is that ultrasonography can detect asymptomatic cases, which results in early treatment and the prevention of serious outcomes. The pathogenesis of GD is suggested to be multifactorial and probably develops from complex interactions between many genetic and environmental factors. It suggests that corticosteroids and oral contraceptives, which contain hormones related to steroid hormones, may be regarded as a model system of cholelithiasis development in man. The achievement in the study of the physiology of bile formation and the pathogenesis of GD has allowed expanding indications for therapeutic treatment of GD.