The importance of extrahepatic biliary anatomy in preventing complications at laparoscopic cholecystectomy

Aberrant anatomy in the context of the critical view of safety

BACKGROUND

The protective impact of the Critical View of Safety (CVS) approach on the vasculo-biliary injuries during laparoscopic cholecystectomy (LC) depends largely upon the understanding of the normal and variant anatomy. Structures exposed during the acquisition of the CVS can deviate from the typical dual configuration of the cystic duct and artery (gallbladder pedicle) representing either a third (supernumerary) or atypical in course (heterotopic) element. The aim of this study was to determine the identity and the frequency of these anatomical elements and to propose anatomic schemata that can guide the achievement of CVS by surgeons.

METHOD

Fourteen anatomic elements that can be encountered during LC were defined by members of the Hellenic task force on the typology of safe cholecystectomy using a literature review and expert consensus. Videos of 279 LCs performed for biliary colic were reviewed noting the presence of a third and or heterotopic anatomic element. In 108 LCs these elements were sought also intraoperatively. A CVS score according to Sanford and Strasberg was assigned to each video.

RESULTS

The normal configuration of the gallbladder pedicle was present in 233 cases (83.51%). A third element was detected in 42 cases (15.05%) and was arterial in 41 cases and biliary in 1 case. A heterotopic course concerned exclusively the cystic artery in 24 cases (8.6%). Neither of these two variant patterns compromised achievement of the CVS during LC. CVS scores improved with the addition of intraoperative assessment.

CONCLUSION

Typical and aberrant anatomy of LC was defined and anatomic schemata proposed to help the surgeon better understand aberrant anatomy and confidently and safely handle any encountered element that deviates from the normal configuration of the gallbladder pedicle during laparoscopic cholecystectomy.

Anatomical Schemata Revealed by the Critical View of Safety Approach: A Proposal of the Hellenic Task Force on the Typology of Safe Laparoscopic Cholecystectomy (HETALCHO)

Background and objectives: Laparoscopic cholecystectomy (LC) is the most commonly performed operation in general surgery in the Western World. Gallbladder surgery, although most of the time simple, always offers the possibility of unpleasant surprises. Despite progress, the incidence of common bile duct injury is 0.2-0.4%, causing devastating implications for the patient and the surgeon. This is mainly due to the failure to identify the normal anatomy properly. The literature review reveals a lack of structured knowledge in the surgical anatomy of cholecystectomy. The aim of this study was to develop a framework with a common anatomical language for safe laparoscopic and open cholecystectomy. Materials and Methods: The Hellenic Task Force group on the typology for Safe Laparoscopic Cholecystectomy performed a critical review of the literature on the laparoscopic anatomy of cholecystectomy. The results were compared with those of a clinical study of 279 patients undergoing LC for uncomplicated symptomatic gallstone disease. Results: Fourteen elements encountered during LC under the critical view of safety (CVS) approach were determined. The typical vascular-biliary pedicle with one cystic duct distributed laterally (or caudally) and one cystic artery medially (or cranially) lying at any point of the hepatocystic space was found in 66% of the cases studied. Anatomical schemata were formulated corresponding to the norm and four variations. Conclusions: The proposed cognitive anatomical schemata summarize simply what one can expect in terms of deviation from the norm. We believe that the synergy between the correct application of the CVS and the structured knowledge of the surgical anatomy in cholecystectomy helps the surgeon to handle non-typical structures safely and to complete the laparoscopic or open cholecystectomy without vascular-biliary injuries.

Magnetic resonance cholangiopancreatography enhanced by virtual reality as a novel tool to improve the understanding of biliary anatomy and the teaching of surgical trainees

Objective

The novel picture archiving and communication system (PACS), compatible with virtual reality (VR) software, displays cross-sectional images in VR. VR magnetic resonance cholangiopancreatography (MRCP) was tested to improve the anatomical understanding and intraoperative performance of minimally invasive cholecystectomy (CHE) in surgical trainees.

Design

We used an immersive VR environment to display volumetric MRCP data (Specto VRTM). First, we evaluated the tolerability and comprehensibility of anatomy with a validated simulator sickness questionnaire (SSQ) and examined anatomical landmarks. Second, we compared conventional MRCP and VR MRCP by matching three-dimensional (3D) printed models and identifying and measuring common bile duct stones (CBDS) using VR MRCP. Third, surgical trainees prepared for CHE with either conventional MRCP or VR MRCP, and we measured perioperative parameters and surgical performance (validated GOALS score).

Setting

The study was conducted out at Clarunis, University Center for Gastrointestinal and Liver Disease, Basel, Switzerland.

Participants

For the first and second study step, doctors from all specialties and years of experience could participate. In the third study step, exclusively surgical trainees were included. Of 74 participating clinicians, 34, 27, and 13 contributed data to the first, second, and third study phases, respectively.

Results

All participants determined the relevant biliary structures with VR MRCP. The median SSQ score was 0.75 (IQR: 0, 3.5), indicating good tolerability. Participants selected the corresponding 3D printed model faster and more reliably when previously studying VR MRCP compared to conventional MRCP: We obtained a median of 90 s (IQR: 55, 150) and 72.7% correct answers with VR MRCP versus 150 s (IQR: 100, 208) and 49.6% correct answers with conventional MRCP, respectively (p < 0.001). CBDS was correctly identified in 90.5% of VR MRCP cases. The median GOALS score was higher after preparation with VR MRCP than with conventional MRCP for CHE: 16 (IQR: 13, 22) and 11 (IQR: 11, 18), respectively (p = 0.27).

Conclusions

VR MRCP allows for a faster, more accurate understanding of displayed anatomy than conventional MRCP and potentially leads to improved surgical performance in CHE in surgical trainees.

Cholecystectomy, porta hepatis stripping, and omental bursectomy

As ovarian cancer commonly involves the visceral organs without boundary, more aggressive procedures are adopted during cytoreductive surgery. One of the most difficult aspect of the operation involves the procedure for the gall bladder, porta hepatis, and omental bursa. As the upper abdominal surgical field is not familiar to the gynecologic surgeon, and the vital organs or vessels are densely positioned, these procedures can be challenging for achieving the optimal cytoreductive surgery. The surgical approaches for advanced ovarian cancer that are required in the upper abdomen have evolved with the progress in surgical techniques. This article will discuss the surgical approach by focusing on cholecystectomy, porta hepatis debulking, and omental bursectomy, as well as the regional anatomy in patients with advanced ovarian cancer.

Anatomy relevant to cholecystectomy

This review discusses anatomical facts that are of relevance to the performance of a safe cholecystectomy. Misinterpretation of normal anatomy and anatomical variations contribute to the occurrence of major postoperative complications like biliary injuries following a cholecystectomy, the incidence being higher with laparoscopic cholecystectomy. A look at the basic anatomy is therefore important for biliary and minimally invasive surgeons. This includes normal anatomy and variations of the biliary apparatus as well as the arterial supply to the gallbladder. Specific anatomical distortions due to the laparoscopic technique, their contribution in producing injury and a preventive strategy based on this understanding are discussed. Investigative modalities that may help in assessing anatomy are considered. Newer insights into the role of anatomic illusions as well as the role of a system-based approach to preventing injuries is also discussed.

Absence of the common bile duct and junction of the cystic duct with the left hepatic duct in a patient with chronic portal vein thrombosis

A50-year-old male patient was admitted to the hospital because of fatigue and a palpable abdominal mass. The diagnoses of chronic renal failure and portal vein thrombosis were established by specific investigations. Incidentally, junction of the cystic duct with the left hepatic duct and absence of the common bile duct were found during endoscopic retrograde cholangiopancreatography study. To the authors' knowledge, this is the first reported case of an absence of the common bile duct and junction of the cystic duct with the left hepatic duct in a patient with chronic portal vein thrombosis. Such lesions may cause unexpected complications during biliary surgery.

Embryology, anatomy, and surgical applications of the extrahepatic biliary system

As technology has improved and the ability to apply this technology in the surgical arena has grown, surgeons have been able to perform more sophisticated operative procedures. Hepatobiliary surgeons are now able to use laparoscopy, immunosuppressive drugs, and technical advances in cryosurgery to accomplish magnificent results. The success and safety of laparoscopic cholecystectomy, orthotopic liver transplantation, and trisegmentectomy for hepatic tumors depend on a high regard for and an accurate knowledge of the anatomy and some of the common embryologic anomalies of the biliary tree. The blood supply, ductal variations, and gallbladder anatomy of this area are often the source of major challenge to unprepared and unaware surgeons. The authors have attempted to stimulate an interest in, a respect for, and perhaps some desire to learn more about the important and fascinating anatomy of this region.