Anatomical variations of the cystic duct: Two case reports

Cholecystitis in a midline gallbladder: A rare ectopic location

Introduction

The ectopic gallbladder is an uncommonly encountered anomaly that surgeons should be aware of. Its diagnosis is difficult but can be elucidated with the use of computed tomography and MRCP.

Presentation of case

We present a case of a 64-year-old patient who presented with abdominal pain, inflammatory epigastric mass and fever. Computed tomography (CT) revealed the presence of a para-umbilical gallbladder with signs of acute cholecystitis. Laparoscopic exploration revealed that the gall bladder was not present in its usual fossa but was seen attached to the midline anterior abdominal wall with extensive adhesion between it and the omentum. Given the complexity of the cholecystectomy via the laparoscopic approach, a conversion to a midline incision was performed. The IOC confirmed the absence of anatomical variants of the biliary tree.

Discussion

An ectopic gallbladder is a difficult entity to diagnose as it can create clinical confusion by tampering with the common clinical presentation of cholecystitis. MRCP is currently one of the most effective preoperative examination methods as it detects the coexistence of biliary tract variation. Laparoscopic surgery is a safe procedure to be performed in the ectopic gallbladder.

Conclusion

Ectopy of the gallbladder is a rare congenital abnormality that should be kept in mind to avoid errors or delays in management.

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Ectopic gallbladder is an extremely rare condition.

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Ectopy of the gallbladder may lead to clinical misdiagnosis, imaging misinterpretation and technical challenges.

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Pre-operative imaging is needed to detect the coexistence of biliary tract variation.

Anatomic Variations of the Cystic Duct in Magnetic Resonance Cholangiopancreatography in Shiraz: A Cross-Sectional Study

BACKGROUND

Anatomic variations of the cystic duct (CD) are commonly encountered. Being aware of these variants will reduce complications subsequent to surgical, endoscopic, or percutaneous procedures. Magnetic resonance cholangiopancreatography (MRCP) is the least invasive and the most reliable modality for biliary anatomy surveys. This study aimed to determine the prevalence of cystic duct variations in the Iranian population.

METHODS

In this retrospective cross-sectional study, MRCP images of 350 patients referred to Shiraz Faraparto Medical Imaging and Interventional Radiology Center from October 2017 to October 2018 were reviewed. The CD course and insertion site to the extrahepatic bile duct (EHBD) was determined and documented in 290 cases. Descriptive statistics and Chi square test were applied for data analysis via SPSS software.

RESULTS

About 77% of cases revealed the classic right lateral insertion to the middle third of EHBD. The insertion of CD to the upper third and the right hepatic duct was 10%, and the insertion to the medial aspect of the middle third of EHBD from anterior or posterior was noted to be about 7.6%. From 2.8% of insertions to the lower third, 1% demonstrated parallel course, and finally, 0.3% of cases presented short CD.

CONCLUSION

CD variations are relatively common, and MRCP mapping prior to the hepatobiliary interventions could prevent unexpected consequences.

The effect and importance of extrahepatic bile duct anatomy variations in the etiology of choledocholithiasis

Background: Biliary stone disease is a frequently encountered problem among the population with a variety of causes and resulting in a wide range of symptoms from vague abdominal discomfort to life-threatening conditions requiring urgent surgical intervention. Magnetic resonance cholangiopancreatography (MRCP) has become a noninvasive radiological diagnostic method extensively used in the evaluation of the biliary tract providing excellent anatomical detail. Apart from the classical causes widely described in the literature in stone etiology, the effect of anatomical variations of the bile tract is a subject that has been investigated recently. The present study aimed to manifest the effect of anatomical variations of the extrahepatic biliary tract on the etiology of choledocholithiasis. Methods: The data of 182 patients who underwent MRCP in our hospital between 2016 and 2021 were retrospectively scanned. The patients were divided into two groups, asymptomatic patients and acute cholangitis. Cystic duct, common hepatic duct, choledochal lengths, and variations in cystic duct opening were analyzed by an experienced radiologist in MRCP. Results: The relation was detected between the cystic choledochal variance of the patients (p<0.001). The cystic duct length of the patients showed statistically significant differences (p<0.05). Conclusion: When the extrahepatic bile duct variations were evaluated, some notable values were found for the etiology, as well as being critical in acute cholangitis. There is a need for studies with larger sample sizes in the literature on this subject.

Variations in the vascular and biliary structures of the liver: a comprehensive anatomical study

PURPOSE

Vascular structures of the liver and the bile ducts are crucial during liver transplantation or liver resection surgery. Here, we report on variations in the vascular structures and bile ducts of 200 patients.

MATERIALS AND METHODS

We reviewed magnetic resonance cholangiopancreatographic and multiple-detector computed tomographic data.

RESULTS

Michels type 1 was detected in 54% of the patients. The other most common variations were, respectively, Michels type 5 (13%) and type 2 (11%). Unclassified variations were defined as Michels type 11; 5% of patients were in this group. Type 1 variations in the hepatic portal vein were detected in 76% of our study group. Other common variations were type 2 (9%) and type 3 (8.5%). The left and intermediate hepatic veins united to become a single vein and then joined the inferior vena cava in 64% of the patients. The right, intermediate, and left hepatic veins joined the inferior vena cava separately in 36% of the patients. Type A, which represents the classic anatomy of the bile duct, was observed in 51.5% of our patients. Type C1 and type B were detected in 15% and 12% of patients, respectively.

CONCLUSIONS

We describe vascular and biliary variations in the livers of our patients.

Anatomical Variations of Cystic Ducts in Magnetic Resonance Cholangiopancreatography and Clinical Implications

Background. Anatomical variations of cystic duct (CD) are frequently unrecognized. It is important to be aware of these variations prior to any surgical, percutaneous, or endoscopic intervention procedures. Objectives. The purpose of our study was to demonstrate the imaging features of CD and its variants using magnetic resonance cholangiopancreatography (MRCP) and document their prevalence in our population. Materials and Methods. This study included 198 patients who underwent MRCP due to different indications. Images were evaluated in picture archiving communication system (PACS) and variations of CD were documented. Results. Normal lateral insertion of CD at middle third of common hepatic duct was seen in 51% of cases. Medial insertion was seen in 16% of cases, of which 4% were low medial insertions. Low insertion of CD was noted in 9% of cases. Parallel course of CD was present in 7.5% of cases. High insertion was noted in 6% and short CD in 1% of cases. In 1 case, CD was draining into right hepatic duct. Congenital cystic dilation of CD was noted in one case with evidence of type IV choledochal cyst. Conclusion. Cystic duct variations are common and MRCP is an optimal imaging modality for demonstration of cystic duct anatomy.

Magnetic resonance cholangiographic evaluation of intrahepatic and extrahepatic bile duct variations

Biliary anatomy and its common and uncommon variations are of considerable clinical significance when performing living donor transplantation, radiological interventions in hepatobiliary system, laparoscopic cholecystectomy, and liver resection (hepatectomy, segmentectomy). Because of increasing trend found in the number of liver transplant surgeries being performed, magnetic resonance cholangiopancreatography (MRCP) has become the modality of choice for noninvasive evaluation of abnormalities of the biliary tract. The purpose of this study is to describe the anatomic variations of the intrahepatic and extrahepatic biliary tree.

Preoperative hepatobiliary imaging: what does the radiologist need to know?

Accurate preoperative reporting is essential in guiding the surgeon in deciding when and how to operate safely and effectively. Critically, this relies on an understanding of the operative issues faced by the surgeon, which is not always appreciated by the radiologist. This paper therefore aims to address this, first focusing on relevant anatomical variants, and then issues specific to laparoscopic cholecystectomy, hepatic transplantation, and finally hepatic resection (including cholangiocarcinoma resection). Throughout the paper, there is an emphasis on associated surgical techniques to add context to the discussion.