The unwanted third wheel in the Calot's triangle: Incidence and surgical significance of caterpillar hump of right hepatic artery with a systematic review of the literature

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.

Rare anatomical variants encountered during laparoscopic cholecystectomy in low resource conditions and the convenient concept of the safe zone of dissection: a prospective observational study at a single center

Purpose

The severity of surrounding adhesions, anomalous anatomy, and technical issues are the main factors that complicate cholecystectomy. This study focused on determining the types and frequency of laparoscopic anatomical variations found during laparoscopic cholecystectomy in our limited-resources condition and on defining the safe zone of dissection.

Methods

This prospective study was conducted at a single center in Aden, Yemen from 2012 to 2019. A total of 375 patients, comprising 355 females (94.7%) and 20 males (5.3%), presented with symptomatic gallbladders and underwent standard four-port laparoscopic cholecystectomy. The regional laparoscopic variations were evaluated and recorded.

Results

Of the 375 patients, 26 (6.9%) had laparoscopic anatomical variations, of whom 19 (73.1%) had vascular variations and seven (26.9%) had ductal variations. The anatomical variations included the following: double cystic artery of separated origin, seven cases (26.9%); Moynihan's hump, six (23.1%); double cystic artery of single origin, four (15.4%); thin long cystic duct, four (15.4%); subvesical duct, three (11.5%); and cystic artery hocking the cystic duct, two (7.7%).

Conclusion

Biliary anatomical variations can be expected in any dissected zone. Most of the detected variants were associated with the cystic artery. An overlooked accessory cysto-biliary communication can cause complicated biliary leakage. A surgeon's skills and knowledge of laparoscopic anatomical variants are essential for performing a safe laparoscopic cholecystectomy.

Pre-Operative Group and Save in Elective and Emergency Laparoscopic Cholecystectomy: Necessity, Cost-Effectiveness, and Own Experience

Background: Laparoscopic cholecystectomy is associated with a high safety profile. This study seeks to quantify the incidence of blood transfusion in both the elective and emergency settings, examine related patient outcomes, and investigate selection criteria for pre-operative Group and Save (G&S) sampling. Methods: A prospective multi-centre observational study was conducted to investigate patients undergoing either elective or emergency laparoscopic cholecystectomy in the UK between January 2020 and May 2021. Multivariate logistical regression models were used to identify patient factors associated with the risk of transfusion and explore outcomes linked to pre-operative G&S sampling. Results: This study comprised 959 patients, with 631 (65.8%) undergoing elective cholecystectomy and 328 (34.2%) undergoing emergency surgery. The median age was 48 years (range: 35-59), with 724 (75.5%) of the patients being female. Only five patients (0.5%) required blood transfusions, receiving an average of three units, with the first unit administered approximately six hours post-operatively. Among these cases, three patients (60%) had underlying haematological conditions. In adjusted models, male gender was significantly associated with the need for a blood transfusion (OR 11.31, p = 0.013), while the presence of a pre-operative Group and Save sample did not demonstrate any positive impact on patient outcomes. Conclusions: The incidence of blood transfusion following laparoscopic cholecystectomy is very low. Male gender and haematological conditions may present as independent risk factors. Pre-operative G&S sampling did not yield any positive impact on patient outcomes and could be safely excluded in both elective and emergency cases, although certain population subsets will warrant further consideration.

Vascular injury during laparoscopic cholecystectomy: An often-overlooked complication

Laparoscopic cholecystectomy is one of the most frequently performed procedures in gastrointestinal surgery worldwide. Bleeding complications due to vascular injuries represent an important cause of morbidity and mortality, especially when facing major bleeding during laparoscopy, where bleeding control can be technically challenging in inexperienced hands. Interestingly, the reported incidence rate of conversion to open surgery due to vascular lesions is approximately 0%-1.9%, with a mortality rate of approximately 0.02%. The primary aim of this article was to perform an up-to-date overview regarding the incidence and surgical management of vascular injuries during laparoscopic cholecystectomy according to the available scientific evidence.

Moynihan's hump of the right hepatic artery in Calot's triangle: a systematic review and meta-analysis of its incidence and surgical importance

INTRODUCTION

A rare variation known as "Moynihan's or caterpillar hump" of the right hepatic artery raises the danger of vascular and biliary injuries during hepatobiliary surgery. This research intends to carefully record every case (i.e., patients undergoing laparoscopic cholecystectomy or cadaver dissections) where the right hepatic artery received a caterpillar hump.

METHODS

The literature search was conducted with the medical subject headings (MeSH) and EMTREE (subject headings unique to Embase) keywords. The keywords with Boolean operators (OR, AND, and NOT) were used to create search strings in all possible combinations to retrieve bibliographic data. Two authors independently performed a risk of bias assessment and data extraction. The random effects model was used to conduct a meta-analysis.

RESULTS

Thirty studies with a total of 8418 subjects reported that Moynihan's hump was present in 3.81% of them, with a predictive interval of 0.88-16.45%. The incidence of the hump was 3.1% in surgical studies (7496 subjects) and 7.22% (95% CI 4.7-10.93%) in cadaveric data (625 cadavers). Only ten studies addressed the relationship between the caterpillar hump and the common bile duct.

CONCLUSION

A patient with an unusually "small cystic artery" or "large right hepatic artery" is likely to have a "caterpillar hump". The caterpillar's hump of the right hepatic artery is subject to rare anatomical variations in its course that increase the risk of incorrect vessel ligation or injury during laparoscopic cholecystectomy.

Management of Postcholecystectomy Complications

Cholecystectomy is one of the most common general surgery procedures performed worldwide. Complications include bile duct injury, strictures, bleeding, infection/abscess, retained gallstones, hernias, and postcholecystectomy syndrome. Obtaining a critical view of safety and following the other tenets of the Safe Cholecystectomy Task Force will aid in the prevention of bile duct injury and other morbidity associated with cholecystectomy.

Moynihan's Lump as an unusual variant of right hepatic artery during a laparoscopic cholecystectomy approach. A case report

Introduction and importance

One of the most important measures during the cholecystectomy procedure is based on a “Culture for Safe Cholecystectomy (CSC)”. Vascular injury reports an open surgery conversion rate of 0 to 1.9% and a mortality of less than 0.02%. The caterpillar or Moynihan's hump configuration is characterized by a tortuous right hepatic artery (RHA) running proximal and/or parallel to the cystic duct and predisposes to a small and/or short cystic artery (CA).

Case presentation

A 65-year-old woman with no relevant clinical history underwent a laparoscopic cholecystectomy (LC) for cholelithiasis; during the procedure a caterpillar or Moynihan's hump was identified.

Clinical discussion

Anatomical variations represent 20-50% of all cases; therefore, CVS is required. The incidence of caterpillar or Moynihan's hump varies between 1% and 13% of all cases. To date, the scientific literature on this topic is limited. The most accepted etiology is related to embryological formation.

Conclusion

Biliary and arterial variations are more frequent than we think, so an anatomical knowledge, CSC and CVS represent a fundamental rule, increasing the safety of the surgical procedure.

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This is a reminder of how variant the anatomy of the biliary tree can be.

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Anatomical variations could increase the risk of inadvertent injury during LC.

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The certainty of a safe cholecystectomy is of great importance.

Indocyanine green (ICG) fluorescent cholangiography during laparoscopic cholecystectomy using RUBINA™ technology: preliminary experience in two pediatric surgery centers

Background

Recently, we reported the feasibility of indocyanine green (ICG) near-infrared fluorescence (NIRF) imaging to identify extrahepatic biliary anatomy during laparoscopic cholecystectomy (LC) in pediatric patients. This paper aimed to describe the use of a new technology, RUBINA™, to perform intra-operative ICG fluorescent cholangiography (FC) in pediatric LC.

Methods

During the last year, ICG-FC was performed during LC using the new technology RUBINA™ in two pediatric surgery units. The ICG dosage was 0.35 mg/Kg and the median timing of administration was 15.6 h prior to surgery. Patient baseline, intra-operative details, rate of biliary anatomy identification, utilization ease, and surgical outcomes were assessed.

Results

Thirteen patients (11 girls), with median age at surgery of 12.9 years, underwent LC using the new RUBINA™ technology. Six patients (46.1%) had associated comorbidities and five (38.5%) were practicing drug therapy. Pre-operative workup included ultrasound (n = 13) and cholangio-MRI (n = 5), excluding biliary and/or vascular anatomical anomalies. One patient needed conversion to open surgery and was excluded from the study. The median operative time was 96.9 min (range 55–180). Technical failure of intra-operative ICG-NIRF visualization occurred in 2/12 patients (16.7%). In the other cases, ICG-NIRF allowed to identify biliary/vascular anatomic anomalies in 4/12 (33.3%), including Moynihan's hump of the right hepatic artery (n = 1), supravescicular bile duct (n = 1), and short cystic duct (n = 2). No allergic or adverse reactions to ICG, post-operative complications, or reoperations were reported.

Conclusion

Our preliminary experience suggested that the new RUBINA™ technology was very effective to perform ICG-FC during LC in pediatric patients. The advantages of this technology include the possibility to overlay the ICG-NIRF data onto the standard white light image and provide surgeons a constant fluorescence imaging of the target anatomy to assess position of critical biliary structures or presence of anatomical anomalies and safely perform the operation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00464-021-08596-7.