Relationship between cystic duct diameter and the presence of cholelithiasis

The anatomy of the cystic duct and its association with cholelithiasis: MR Cholangiopancreatographic study

INTRODUCTION

The aims of this article are to detail the anatomy of the cystic duct in patients with and without gallstones as it relates to maneuvering of the duct during endoscopic transpapillary gallbladder cannulation, and to elucidate its role in the dynamics of bile flow during gallbladder contraction.

MATERIAL AND METHODS

One hundred MRCPs were retrieved from the prospectively maintained radiology data system to assess the configuration of the cystic duct and its confluence vis-a-vis the main biliary duct.

RESULTS

The configuration of the cystic duct was broadly classified into four types: Angular (44%), Linear (40%), Spiral (11%) and Complex (5%). The level of emergence of the cystic duct from the bile duct was proximal in 29%, middle in 49% and distal in 20%. Its direction from the bile duct was to the right and angled upward in 69%, right and angled downward in 15%, left and angled upward in 13%, and left and angled downward in 1%. Its orifice was on the lateral surface of the bile duct in 50%, posterior in 19%, anterior in 15% and medial in 14%. In two cases, the cystic duct opened directly into the duodenum. Tortuous cystic ducts and non-lateral unions with the bile duct were significantly more prevalent in gallstone cases than the non-gallstone group (p=0.02).

CONCLUSIONS

The present study details the spatial anatomy of the cystic duct vis a vis the main biliary duct. This has not been well investigated to date but has become increasingly relevant with the advent of recent gallbladder interventions.

Evaluation of the safety of using harmonic scalpel during laparoscopic cholecystectomy in children: A preliminary report

BACKGROUND AND OBJECTIVE

In spite of being one of the most common surgical procedures performed in adults, laparoscopic cholecystectomy (LC) is relatively uncommon in the pediatric age group. Most surgeons prefer to dissect the cystic duct using a monopolar electrosurgical hook and occlude it with simple metal clips. Although the safety of using the ultrasonically-activated shears, e.g., harmonic scalpel for dissection of the gallbladder is confirmed in many studies, its efficacy in the closure of the cystic artery and duct in adults is still debatable. Furthermore, very few reports studied its safety in children during LC. The aim of our work is to study the safety and efficacy of ultrasonic shears in controlling the cystic duct and artery during LC in children.

MATERIALS AND METHODS

A prospective study was conducted from May 2017 to April 2020, where all children having symptomatic gallbladder stone disease were included in the study. HS was used as a sole instrument in gallbladder dissection as well as in controlling cystic duct and artery. No metal clips or sutures were used throughout the procedure.

RESULTS

A total of forty-two children having symptomatic gallstone disease were included in the study. The main indication for LC was hemolytic anemia. Their age ranged from 3 to 13 years with a mean of 8.4 ± 3.25 years. All operations were completed laparoscopically, i.e., no conversion to open surgery was needed. The mean operative time was 40 ± 10.42 min. There were no intraoperative complications apart from gall bladder perforation in two cases during dissection from the liver bed while the postoperative recovery was smooth in all patients. Patients started oral feeding after 11.30 ± 3.01 h. The mean time for discharge was 25.47 ± 7.49 h, ranging from 14 to 48 h. Postoperative ultrasound for all cases showed no evidence of minor or major bile leaks or CBD injuries.

CONCLUSION

This is the first report to evaluate the use of HS as a sole instrument during LC in the pediatric age group. HS is a safe and efficient instrument that can be used alone in gallbladder dissection as well as in controlling cystic duct and artery during LC in children.

Regression tree for choledocholithiasis prediction

OBJECTIVES

The aim of this study was to develop and compare the predictive accuracy of classification and regression tree (CART) analysis with logistic regression (LR) for predicting common bile duct stones (CBDS) in patients subjected to laparoscopic cholecystectomy.

PATIENTS AND METHODS

We prospectively collected preoperative (demographic, biochemical, ultrasonographic) and intraoperative (intraoperative cholangiography, cystic duct diameter) data for 154 patients considered for elective laparoscopic cholecystectomy at the department of General Surgery at Gornji Milanovac from 2013 through 2014. Univariate and multivariate regression analyses were used to determine independent predictors of CBDS. The CART analysis was carried out using the predictors identified by LR analysis. Various measures for the assessment of risk prediction models were determined, such as predictive ability, accuracy, the area under the receiver operating characteristic curve, and clinical utility using decision curve analysis.

RESULTS

The most decisive variable at the time of classification was the cystic duct diameter category, the alkaline phosphatase, and dangerous stones. The CART model was shown to have good discriminatory ability (93.9%). Accuracy was similar in both models, ranging from 92.9% in the CART model and 93.5% in the LR model. In decision curve analysis, the CART model outperformed the LR model.

CONCLUSION

We developed a user-friendly risk model that can successfully predict the presence of choledocholithiasis in patients planned for elective cholecystectomy. However, before recommending its use in clinical practice, a larger and more complete database should be used to further clarify the differences between models in terms of prediction of the CBDS.

Instrumental detection of cystic duct stones during laparoscopic cholecystectomy

Residual cystic duct stones (CDSs) after cholecystectomy have been recognized as a cause of post-cholecystectomy pain. This study was undertaken to determine the incidence of CDSs during laparoscopic cholecystectomy (LC). A cohort of 330 consecutive patients (80 males and 250 females) undergoing LC between November 2006 and May 2010 was studied. Their age ranged between 16 and 88 years (median 50, IQR: 36.62). The data were prospectively collected of preoperative liver function tests, imaging, the presence of intraoperative CDSs, and common bile duct stones at on-table cholangiogram. CDSs were detected intraoperatively in 64 of the 330 patients (19%). Ultrasound failed to detect CDSs in any of these cases. Deranged liver function tests were noted in 73% of the patients with CDSs and in 57% without CDSs. Common bile duct stones were detected in 9% (29) of the 330 patients. CDSs occur commonly at routine cholecystectomy, and preoperative investigations are not helpful in their diagnosis. As CDSs may lead to postoperative morbidity, they should be actively sought out during surgery if present.

An estimation of the number of cells in the human body

BACKGROUND

All living organisms are made of individual and identifiable cells, whose number, together with their size and type, ultimately defines the structure and functions of an organism. While the total cell number of lower organisms is often known, it has not yet been defined in higher organisms. In particular, the reported total cell number of a human being ranges between 10(12) and 10(16) and it is widely mentioned without a proper reference.

AIM

To study and discuss the theoretical issue of the total number of cells that compose the standard human adult organism.

SUBJECTS AND METHODS

A systematic calculation of the total cell number of the whole human body and of the single organs was carried out using bibliographical and/or mathematical approaches.

RESULTS

A current estimation of human total cell number calculated for a variety of organs and cell types is presented. These partial data correspond to a total number of 3.72 × 10(13).

CONCLUSIONS

Knowing the total cell number of the human body as well as of individual organs is important from a cultural, biological, medical and comparative modelling point of view. The presented cell count could be a starting point for a common effort to complete the total calculation.

Gallbladder abnormalities in carcinoma of pancreatic head: findings on MR imaging

BACKGROUND

Our objective is to study the gallbladder abnormalities on MR images associated with carcinoma of the pancreatic head.

METHODS

Thirty-six patients who had surgical resection of pancreatic head carcinoma were retrospectively analyzed regarding the appearance of the tumor and gallbladder on MR imaging performed within one month before surgery. The changes of the gallbladder wall, and the dimension of the gallbladder, cystic duct, pericholecystic region, and common bile duct (CBD) on MR imaging were noted.

RESULTS

About 92% (33/36) of patients had at least one gallbladder abnormality on MR imaging, including thickened gallbladder wall (58%), gallbladder wall striation (19%), gallbladder wall severe enhancement (44%), enlarged gallbladder (33%), gallbladder stone (19%), dilatation of cystic duct (67%), focally increased liver parenchymal enhancement adjacent to the gallbladder (19%), and pericholecystic fluid (11%). 64% of patients had dilated CBD. The diameter of the cystic duct was correlated with those of the CBD (r = 0.45, P < 0.01) and gallbladder (r = 0.56, P < 0.0001). Enlarged gallbladder, dilatation of the cystic duct, and CBD were correlated with chronic cholecystitis.

CONCLUSION

Most patients with pancreatic head carcinoma show gallbladder abnormalities on MR imaging. Cystic duct dilatation follows CBD dilatation and is the primary cause for dilated gallbladder and chronic cholecystitis in carcinoma of pancreatic head.

Investigation of the functional three-dimensional anatomy of the human cystic duct: a single helix?

Clinical research into the formation of gallstones has indicated that the anatomy of the cystic duct is one of a number of factors contributing to the formation of gallstones. The cystic duct allows low-viscosity hepatic bile to enter the gallbladder under low pressure and the expulsion of a more viscous gallbladder bile, but little is known about this transport mechanism and the effect of anatomical variations in structure. This article describes the variation in geometry of the cystic duct, obtained from acrylic resin casts of the neck and first part of the cystic duct in gallbladders removed for gallstone disease and obtained from patients undergoing partial hepatectomy for metastatic disease. The data obtained allowed us to formulate a number of standard terms for describing cystic duct morphology and demonstrate that the term "spiral valve" is only partially correct when describing the duct anatomy. In over half of the casts, spiraling was not the dominant feature of the cystic duct. Additionally, the term valve implies active resistance to flow in one direction, whereas the internal baffles of the cystic duct would serve to regulate bile flow in both directions. These data are useful for realistic 3D modeling of fluid-structure interactions of the flow of bile in the human cystic duct.

Cystic duct and Heister's "valves"

The anatomy and physiology of the cystic duct have been relatively neglected by anatomists and the function of the spiral mucosal folds or "valves" of Heister, first described in 1732, remains obscure. The gross and microscopic anatomy of the cystic duct is reviewed together with results from laboratory investigations into the function of the cystic duct and its spirally arranged folds. The duct and spiral folds contain muscle fibers responsive to pharmacologic, hormonal, and neural stimuli. There is, however, no convincing evidence of a discrete muscular sphincter within the duct. Although the cystic duct is unlikely to play a major role in gallbladder filling and emptying, it appears to function as more than a passive conduit. Coordinated, graded muscular activity in the cystic duct in response to hormonal and neural stimuli may facilitate gallbladder emptying. The principal function of the internal spiral folds that are found in man and other animals may be to preserve patency of this narrow, tortuous tube rather than to regulate bile flow.

The flow of bile in the human cystic duct

Clinical studies suggest that the flow of bile in the biliary system may be a contributing factor in the pathogenesis of cholelithiasis, but little is known about its transport mechanism. This paper reports a numerical study of steady flow in human cystic duct models. In order to obtain parametric data on the effects of various anatomical features in the cystic duct, idealised models were constructed, first with staggered baffles in a channel to represent the valves of Heister and lumen. The qualitative consistency of these findings are validated by modelling two of the real cystic ducts obtained from operative cholangiograms. Three-dimensional (3D) models were also constructed to further verify the two-dimensional (2D) results. It was found that the most significant geometric parameter affecting resistance is the baffle clearance (lumen size), followed by the number of baffles (number of folds in the valves of Heister), whilst the least significant ones are the curvature of the cystic duct and the angle between the neck and the gallbladder. The study presented here forms part of a larger project to understand the functions of the human cystic duct, especially the influence of its various anatomical structures on the resistance to bile flow, so that it may aid the assessment of the risk of stone formation in the gallbladder.

Three-dimensional sonographic evaluation of the common bile duct

OBJECTIVE

To assess the accuracy of three-dimensional sonographic measurements of the common bile duct compared with standard two-dimensional anteroposterior measurement of the common duct.

METHODS

Fifty-five consecutive patients referred for abdominal sonography underwent standard two-dimensional abdominal sonography followed by three-dimensional sonographic data acquisition of the right upper quadrant. A radiologist blinded to the results of the two-dimensional examination later measured the three-dimensional long axis anteroposterior common duct diameter and three-dimensional short axis anteroposterior and transverse common duct diameters.

RESULTS

The mean average common duct diameter as measured by two-dimensional sonography (long axis anteroposterior) was 3.6 mm. The mean average common duct diameter as measured by long axis anteroposterior three-dimensional sonography was 4.1 mm. The mean average common duct diameter as measured by anteroposterior short axis three-dimensional sonography was 4.1 mm, and by transverse short axis three-dimensional sonography, it was 4.4 mm. The two-dimensional common duct measurement correlated with the long axis anteroposterior three-dimensional measurement (P < .001), the short axis anteroposterior three-dimensional measurement (P < .001), and the short axis transverse three-dimensional measurement (P < .005) by the Spearman rank order correlation coefficient test.

CONCLUSIONS

Three-dimensional sonographic measurements of the common bile duct correlate highly with two-dimensional measurements, validating the use of three-dimensional sonography as a reliable method for evaluation of common bile duct size.

Choledocholithiasis: a prospective study of spontaneous common bile duct stone migration

BACKGROUND

The rate of spontaneous migration of bile duct stones through the duodenal papilla is not well known. Endoscopic retrograde cholangiography (ERC) has been the standard method to diagnose bile duct stones, but accumulating data show there is a good agreement between ERC and endoscopic ultrasonography (EUS). The aim of the study was to evaluate the incidence and time course of stone migration in patients with bile duct stones by analyzing discrepancies between EUS and ERC as a function of the elapsed time between these two procedures. Stone migration was considered as the absence of stones at time of ERC regardless of the number of stones seen at EUS.

METHODS

The main criterion for inclusion was the presence of bile duct stone as shown by EUS. Ninety-two consecutive patients were prospectively included in this study.

RESULTS

Choledocholithiasis was absent at ERC in 12 patients. In univariate analysis, presence of gallbladder was significantly associated with an increased rate of stone migration (correction for multiple testing would remove this statistical significance). The size of the stone was the only independent factor to predict migration.

CONCLUSION

Migration occurred in about 21% of cases within 1 month. Our study emphasizes the need to analyze carefully the results of comparative imaging studies of bile duct stones.

Ultrastructural aspects of human cystic duct epithelium as a result of cholelithiasis and cholesterolosis

Although there is a large body of data on the gallbladder and the importance of the cystic duct in surgical procedures, there is insufficient data regarding the morphology of the human cystic duct. In the present study, transmission electron microscopic (TEM) and scanning electron microscopic (SEM) survey of several surgical and autopsy cystic ducts in cholelithiasis and cholesterolosis is reported. In cholelithiasis, similar to gallbladder epithelium, the cystic duct epithelial cells display minor-to-severe alterations of the epithelial surface accompanied by variable erosion of the epithelium. Areas of intact surface epithelium demonstrate microvilli-covered cells coated by a rich glycocalyx and mucous production. In other areas, apical excrescences are associated with mucus hyperproduction and secretory events. Lipoid bodies are also present in many cells and especially in many of the cells' subliminal apical areas. In cholesterolosis, mucous secretory granules appear dilated, fatty deposits are infrequent, and peculiar intracellular cholesterol deposits can be detected in the apical and subapical region of cells and around condensed mitochondria. Following elective cholecystectomies, predominantly in association with cholelithiasis, eroded areas were detected; therefore, it appears that the action of intraluminal calculi may be a principal causative factor in discrete epithelial erosions of the cystic duct. Intraluminal calculi/ debris, along with the alteration of mucus, cell sloughing, and a decreased pool of bile acids and motility may participate in the gallstone nucleation process. The peculiar cholesterol inclusions may also play a role in that nucleating process.