LABEL procedure: Laser-Assisted Bile duct Exploration by Laparoendoscopy for choledocholithiasis: improving surgical outcomes and reducing technical failure

Mirizzi Syndrome-The Past, Present, and Future

Mirizzi syndrome is a complication of gallstone disease caused by an impacted gallstone in the infundibulum of the gallbladder or within the cystic duct, causing chronic inflammation and extrinsic compression of the common hepatic duct or common bile duct. Eventually, mucosal ulceration occurs and progresses to cholecystobiliary fistulation. Numerous systems exist to classify Mirizzi syndrome, with the Csendes classification widely adopted. It describes five types of Mirizzi syndrome according to the presence of a cholecystobiliary fistula and its corresponding severity, and whether a cholecystoenteric fistula is present. The clinical presentation of Mirizzi syndrome is non-specific, and patients typically have a longstanding history of gallstones. It commonly presents with obstructive jaundice, and can mimic gallbladder, biliary, or pancreatic malignancy. Achieving a preoperative diagnosis guides surgical planning and improves treatment outcomes. However, a significant proportion of cases of Mirizzi syndrome are diagnosed intraoperatively, and the presence of dense adhesions and distorted anatomy at Calot's triangle increases the risk of bile duct injury. Cholecystectomy remains the mainstay of treatment for Mirizzi syndrome, and laparoscopic cholecystectomy is increasingly becoming a viable option, especially for less severe stages of cholecystobiliary fistula. Subtotal cholecystectomy is feasible if total cholecystectomy cannot be performed safely. Additional procedures may be required, such as common bile duct exploration, choledochoplasty, and bilioenteric anastomosis. Conclusions: There is currently no consensus for the management of Mirizzi syndrome, as the management options depend on the extent of surgical pathology and availability of surgical expertise. Multidisciplinary collaboration is important to achieve diagnostic accuracy and guide treatment planning to ensure good clinical outcomes.

Learning curve for performing laparoscopic common bile duct exploration in biliary surgery 2.0 era

BACKGROUND

Recent trials and metanalysis have demonstrated the favorable results of laparoscopic cholecystectomy (LC) and laparoscopic common bile duct exploration (LCBDE) for the treatment of cholecysto-choledocholithiasis. The aim of this study was to evaluate the LC + LCBDE learning curve including transcystic and transductal approaches and its effect on the outcomes.

METHODS

We identified all unselected patients who underwent LC + LCBDE by a single surgeon between May 2017 and July 2021. Pre-, intra-, and postoperative data were analyzed using the cumulative sum (CUSUM) analysis to evaluate the learning curve.

RESULTS

A total of 110 patients were included. Total postoperative complications rate was 12.7%, including bile leakage in six (5.5%) patients. Mean length of hospital stay was 2.7 (1-14) days. No patient had conversion to open surgery. The CUSUM graph divided the learning curve into three distinct phases: (1) Learning (1-38), (2) Competence (39-61) and (3) Proficiency (62-110). There was a significant increase in the transcystic approach rate with each phase (44.7% vs 73.9% vs 98%; P < .001). A significant decrease in the operative time (150.9 vs 117.6 vs 99.9 min; P < .001) and complication rate (21.1% vs 21.7% vs 2%; P = .01) were observed across the three phases.

CONCLUSION

Our data suggest that the learning curve for complete competence in LC + LCBDE is approximately 60 cases, provided that proper training is available. The initial learning phase can be carried out safely and efficiently with acceptable results.

Utilization of Laparoscopic Choledochoscopy During Bile Duct Exploration and Evaluation of the Wiper Blade Maneuver for Transcystic Intrahepatic Access

OBJECTIVE

This study aims to examine the indications, techniques, and outcomes of choledochoscopy during laparoscopic bile duct exploration and evaluate the results of the wiper blade maneuver (WBM) for transcystic intrahepatic choledochoscopy.

SUMMARY OF BACKGROUND DATA

Choledochoscopy has traditionally been integral to bile duct explorations. However, laparoscopic era studies have reported wide variations in choledochoscopy availability and use, particularly with the increasing role of transcystic exploration.

METHODS

The indications, techniques, and operative and postoperative data on choledochoscopy collected prospectively during transcystic and choledo- chotomy explorations were analyzed. The success rates of the WBM were evaluated for the 3 mm and 5 mm choledochoscopes.

RESULTS

Of 935 choledochoscopies, 4 were performed during laparoscopic cholecystectomies and 931 during 1320 bile duct explorations (70.5%); 486 transcystic choledochoscopies (52%) and 445 through choledochotomies (48%). Transcystic choledochoscopy was utilized more often than blind exploration (55.7%% vs 44.3%) in patients with emergency admissions, jaundice, dilated bile ducts on preoperative imaging, wide cystic ducts, and large, numerous or impacted bile duct stones. Intrahepatic choledochoscopy was successful in 70% using the 3 mm scope and 81% with the 5 mm scope. Choledochoscopy was necessary in all 124 explorations for impacted stones. Twenty retained stones (2.1%) were encountered but no choledochoscopy related complications.

CONCLUSIONS

Choledochoscopy should always be performed during a chol- edochotomy, particularly with multiple and intrahepatic stones, reducing the incidence of retained stones. Transcystic choledochoscopy was utilized in over 50% of explorations, increasing their rate of success. When attempted, the transcystic WBM achieves intrahepatic access in 70%-80%. It should be part of the training curriculum.

Novel advances in surgery for Gallstone Disease

PURPOSE OF REVIEW

Examine recent advances in the treatment of patients with complex gallstone disease.

RECENT FINDINGS

Laparoscopic common bile duct exploration (LCBDE) has been shown to be an effective and safe treatment for choledocholithiasis, resulting in decreased hospital length of stay and costs when compared with ERCP plus laparoscopic cholecystectomy (LC). Novel simulator-based curricula have recently been developed to address the educational gap that has resulted in an underutilization of LCBDE. Patients with cholecystitis who are too ill to safely undergo LC have traditionally been treated with percutaneous cholecystostomy (PC). Endoscopic ultrasound (EUS) guided gallbladder drainage is a novel definitive treatment for such patients and has been shown to result in decreased complications and hospital readmissions compared to PC. The management of symptomatic gallstone disease during pregnancy has evolved over the last several decades. While it is now well established that laparoscopic procedures under general anesthesia are safe throughout a pregnancy, recent studies have suggested that laparoscopic cholecystectomy during the third trimester specifically may result in higher rates of preterm labor when compared with non-operative management. Finally, indocyanine green (ICG) fluorescence cholangiography is a novel imaging modality that has been used during laparoscopic cholecystectomy and may offer better visualization of biliary anatomy during dissection when compared with traditional intraoperative cholangiography. A number of recent technological, procedural, educational, and research innovations have enhanced and expanded treatment options for patients with complex gallstone disease.

Controversias en cirugía: colelitiasis y coledocolitiasis ¿Exploración de vías biliares laparoscópica más colecistectomía laparoscópica (cirugía en un paso) o CPRE y colecistectomía laparoscópica (cirugía en dos pasos)?

Introducción. La colelitiasis tiene una prevalencia del 15 % y el 21 % tendrá coledocolitiasis al momento de la colecistectomía, con 50 % de probabilidad de presentar complicaciones asociadas. Desde el advenimiento de la colecistectomía laparoscópica, el abordaje de la coledocolitiasis ha sido endoscópico, usualmente en un tiempo diferente al vesicular, sin embargo, los avances en laparoscopia han permitido explorar la vía biliar común por la misma vía, pudiendo realizar ambos procedimientos en el mismo tiempo de forma segura. Métodos. Se realizó una búsqueda de la literatura existente con relación al enfoque para el manejo de la colecistocoledocolitasis en un paso comparado con dos pasos. Resultados. Existe evidencia que demuestra mayor efectividad del abordaje en dos pasos, con CPRE y posterior colecistectomía laparoscópica, sobre el abordaje en un paso, especialmente en la tasa de fuga biliar y de cálculos retenidos. El enfoque en un paso con exploración de vías biliares y colecistectomía laparoscópica en el mismo tiempo es seguro, con alta tasa de éxito, baja incidencia de complicaciones, menor estancia hospitalaria y costos. Conclusión. El abordaje laparoscópico en un solo paso es un procedimiento seguro y eficaz para el manejo de la colecisto-coledocolitiasis, con el beneficio de estancia hospitalaria menor, sin embargo, se requieren habilidades técnicas avanzadas en cirugía laparoscópica. En nuestro medio ya existe una infraestructura para el manejo híbrido con CPRE y colecistectomía laparoscópica, pudiéndose realizar ambos en el mismo tiempo, para reducir estancia y costos.

Contemporary management of concomitant gallstones and common bile duct stones: a survey of Spanish surgeons

BACKGROUND

Concomitant gallstones and common bile duct stones (CBDS) is a relatively frequent presentation. The optimal treatment remains controversial and the debate persists between two strategies. The one-stage approach: laparoscopic cholecystectomy with laparoscopic common bile duct exploration (LCBDE) has been shown to be equally safe and more cost-effective than the more traditional two-stage approach: endoscopic retrograde cholangiography followed by laparoscopic cholecystectomy (ERCP + LC). However, many surgeons worldwide still prefer the two-stage procedure. This survey evaluated contemporary management of CBDS in Spain and assessed the impact of surgeon and hospital factors on provision of LCBDE.

METHODS

A 25-item, web-based anonymous survey was sent to general surgeons members of the Spanish Surgeons Association. Descriptive statistics were applied to summarize results.

RESULTS

Responses from 305 surgeons across 173 Spanish hospitals were analyzed. ERCP is the initial approach for preoperatively suspected CBDS for 86% of surgeons. LCBDE is the preferred method for only 11% of surgeons and only 11% treat more than 10 cases per year. For CBDS discovered intraoperatively, 59% of respondents attempt extraction while 32% defer to a postoperative ERCP. The main reasons cited for not performing LCBDE were lack of equipment, training and timely availability of an ERCP proceduralist. Despite these barriers, most surgeons (84%) responded that LCBDE should be implemented in their departments.

CONCLUSIONS

ERCP was the preferred approach for CBDS for the majority of respondents. There remains limited use of LCBDE despite many surgeons indicating it should be implemented. Focused planning and resourcing of both training and operational demands are required to facilitate adoption of LCBDE as option for patients.

Comparison of intraoperative endoscopic retrograde cholangiopancreatography and laparoscopic common bile duct exploration combined with laparoscopic cholecystectomy for treating gallstones and common bile duct stones: a systematic review and meta-analysis

BACKGROUND

This study aimed to compare the efficacy and safety of laparoscopic cholecystectomy combined with intraoperative endoscopic retrograde cholangiopancreatography (LC-IntraERCP) and laparoscopic cholecystectomy combined with laparoscopic common bile duct exploration (LC-LCBDE) to determine which one-stage therapeutic strategy provides better outcomes for patients with gallstones and common bile duct stones.

METHODS

Cochrane Library, EMBASE, PubMed, and Web of Science databases were searched to identify eligible articles from the database inception to September 2020. The revised Cochrane risk of bias tools for randomized trials (RoB-2) and non-randomized interventions (ROBINS-I) was used to assess the quality of the included studies. The overall quality of evidence was assessed through the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool. The primary outcomes consisted of surgical success, retained stones, and overall postoperative complications, while secondary outcomes included postoperative bleeding, postoperative pancreatitis, postoperative bile leakage, conversion to laparotomy, and operative time.

RESULTS

Eight studies (four RCTs and four Non-RCTs with high quality) with 2948 patients were included. No significant difference was seen between the two groups regarding surgical success, overall postoperative complications, conversion to laparotomy, and operative time. The meta-analysis demonstrated that in the LC-IntraERCP group, the rate of retained stones (OR 0.51, 95% CI 0.28-0.91) and postoperative bile leakage were lower (OR 0.25, 95% CI 0.09-0.69), while in the LC-LCBDE group, postoperative bleeding (OR 5.24, 95% CI 1.65-16.65) and postoperative pancreatitis (OR 4.80, 95% CI 2.35-9.78) decreased.

CONCLUSIONS

LC-IntraERCP and LC-LCBDE exhibited similar efficacies when surgical success rate, overall postoperative complications, conversion to laparotomy, and operative time were compared. However, LC-IntraERCP is probably to be more effective in terms of lowering the rate of retained stones.

Porcine Aorto-Renal Artery (PARA) model for laparoscopic transcystic common bile duct exploration: the evolution of a training model to meet new clinical needs

BACKGROUND

The transcystic approach to laparoscopic common bile duct exploration has gained popularity for the single-stage management of choledocholithiasis with concomitant gallstones. Our team previously described the use of a porcine aorta segment to simulate the common bile duct during laparoscopic skill training.

METHODS

With the advent of the transcystic approach as a contender for the first-line technique of accessing the common bile duct, we present an evolution of the laparoscopic training model using a Porcine Aorta-Renal Artery (PARA) specimen to simulate the structural integrity, dimensions and spatial distribution of both the human cystic and common bile ducts.

RESULTS

This training model allows the use of a choledochoscope for transcystic exploration of the biliary tree. It combines fidelity and reproducibility required for a simulated training model to offer experience in laparoscopic transcystic common bile duct exploration. Validation of the model was demonstrated by 21 surgeons who completed a questionnaire after performing the simulated procedure. In all sections assessing reliability, face validity and content validity of the model, mean rating scores were between 4 and 5 out of five (good or excellent).

CONCLUSIONS

We present the evolution of an established training model for laparoscopic common bile duct exploration which focusses the attention on the transcystic approach to the common bile duct and the use of lithotripsy techniques. The need for such a model reflects the shift in the current practice of the laparoendoscopic management of choledocholithiasis with concomitant gallstones from transductal to transcystic approach.

Application of Laparoscopic Technique in the Treatment of Hepatolithiasis

Hepatolithiasis is commonly encountered in Southeastern and East Asian countries, and its incidence is increasing in Western countries. For symptomatic hepatolithiasis or asymptomatic hepatolithiasis with signs of liver atrophy or malignancy, surgical intervention is needed, especially when peroral cholangioscopy and percutaneous transhepatic cholangioscopic lithotomy are not suitable or fail to be performed. Currently, laparoscopic surgery is gradually replacing traditional open surgery and becoming a better option. Various types of laparoscopic surgeries, including laparoscopic hepatectomy, laparoscopic biliary exploration through the common bile duct or the hepatic duct stump, and robotic-assisted laparoscopic surgery, have been developed for the treatment of simple hepatolithiasis, hepatolithiasis concomitant with choledocholithiasis, recurrent hepatolithiasis, and complicated hepatolithiasis. The related clinical experience is gradually accumulating. In this review, the laparoscopic applications and their advantages will be summarized. In most cases, the laparoscopic technique could provide the advantages of less trauma, reduced blood loss, and faster postoperative recovery.

The ABCdE score for PREdicting Lithotripsy Assistance during transcystic Bile duct Exploration by Laparoendoscopy (PRE-LABEL)

BACKGROUND

Common bile duct (CBD) stones are reported in ~ 15% of patients who undergo laparoscopic cholecystectomy for symptomatic gallstones. Prior to lithotripsy techniques, transcystic laparoscopic common bile duct exploration (LCBDE) was limited to smaller CBD stones. The addition of lithotripsy to LCBDE increases cost, operative time and staffing requirements. Predicting which patients might require lithotripsy would be useful in operative planning. The primary aim was to investigate clinical variables for predicting lithotripsy assistance during transcystic bile duct exploration by laparoendoscopy (PRE-LABEL). Secondary aims were to develop and validate a predictive scoring tool.

METHODS

A retrospective review of a prospectively collected database of consecutive patients who underwent transcystic LCBDE at a single centre in the UK was performed to investigate clinical variables for PRE-LABEL and develop a scoring tool (ABCdE score: age, bilirubin, CBD diameter, ERCP). Binary logistic regression was used to investigate which independent variables (predictors) were associated with lithotripsy assistance during transcystic LCBDE. The ABCdE score was applied to both UK and Spain patient cohorts to determine its sensitivity, specificity and accuracy.

RESULTS

From 8 pre-operative clinical variables analysed, age ≤ 40 years, bilirubin > two-times upper limit of normal, CBD diameter ≥ 10 mm and ERCP failure of stone extraction were independent predictors of requiring lithotripsy during transcystic LCBDE and formed the ABCdE score. The hazard ratios were 2.87, 3.79, 2.78 and 10.06, respectively. An ABCdE score ≥ 2 resulted in 71% sensitivity, 81% specificity and 79% accuracy in predicting lithotripsy during LCBDE (UK cohort). Validation using a contemporary cohort from Spain yielded similar sensitivity, specificity and accuracy.

CONCLUSIONS

This study represents the only study to date reporting independent predictors of requiring lithotripsy assistance during transcystic LCBDE. ABCdE score ≥ 2 can highlight patients that may require lithotripsy in order to avoid failure of transcystic LCBDE and therefore avoid choledochotomy or post-operative ERCP.

Transductal versus transcystic laparoscopic common bile duct exploration: an institutional review of over four hundred cases

BACKGROUND

Many studies have failed to demonstrate significant differences between single- and two-staged approaches for the management of choledocholithiasis with concomitant gallstones in terms of post-operative morbidity. However, none of these studies paid specific attention to the differences between the methods of accessing the bile duct during laparoscopy. The aim of this study was to report outcomes of transcystic versus transductal laparoscopic common bile duct exploration (LCBDE) from our experience of over four hundred cases.

METHODS

Retrospective review of 416 consecutive patients who underwent LCBDE at a single-centre between 1998 and 2018 was performed. Data collected included pre-operative demographic information, medical co-morbidity, pre-operative investigations, intra-operative findings (including negative choledochoscopy rates, use of holmium laser lithotripsy and operative time) and post-operative outcomes.

RESULTS

Transductal LCBDE via choledochotomy was achieved in 242 patients (58.2%), whereas 174 patients (41.8%) underwent transcystic LCBDE. Stone clearance rates, conversion to open surgery and mortality were similar between the two groups. Overall morbidity as well as minor and major post-operative complications were significantly higher in the transductal group. The main surgery-related complications were bile leak (5.8% vs 1.1%, p = 0.0181) and pancreatitis (7.4% vs 0.6%, p = 0.0005). Median length of post-operative stay was also significantly greater in the transductal group.

CONCLUSION

This study represents the largest single study to date comparing outcomes from transcystic and transductal LCBDE. Where possibly, the transcystic route should be used for LCBDE and this approach can be augmented with various techniques to increase successful stone clearance and reduce the need for choledochotomy.

Laparoscopic management of type II Mirizzi syndrome

BACKGROUND

Mirizzi syndrome is an uncommon complication of longstanding gallstone disease. Pre-operative diagnosis is challenging, and to date, there is no consensus on the standard management for this condition. Until recently open cholecystectomy was the standard of care for type II Mirizzi syndrome (McSherry classification). The objective of this study was to assess the incidence and management of type II Mirizzi syndrome in patients with proven or suspected choledocholithiasis undergoing laparoscopic common bile duct (CBD) exploration and present our experience in the laparoscopic management of this rare condition over the last 21 years.

METHODS

Prospective data collection of eleven cases of type II Mirizzi syndrome amongst a series of 425 laparoscopic bile duct explorations was performed between 1998 and 2019. Demographic, clinical, diagnostic, intra-operative, and post-operative data were recorded.

RESULTS

The incidence of type II Mirizzi syndrome was 2.6% in 425 laparoscopic CBD explorations. All operations were completed laparoscopically with closure of the defect over a decompressed CBD (T-tube n = 3, antegrade stent n = 5, transcystic drain n = 2), and in one case a non-drained duct was closed with Endoloop. Stone clearance rate was 100% (11 cases). In two patients the transinfundibular approach was used in conjunction with holmium laser lithotripsy to enable choledochoscopy and successful stone clearance. Three patients were complicated in the post-operative period with bile leak (n = 2) and lower respiratory tract infection (n = 1). An incidental gallbladder carcinoma was found in one patient.

CONCLUSION

Laparoscopic management of type II Mirizzi syndrome is feasible and safe when performed by experienced laparoscopic foregut surgeons. Laparoscopy and choledochoscopy can be combined with novel approaches and techniques to increase the likelihood of treatment success.

Holmium laser lithotripsy improves the rate of successful transcystic laparoscopic common bile duct exploration

Purpose

Transcystic laparoscopic common bile duct exploration (LCBDE) seems safer than transductal LCBDE and is associated with fewer biliary complications. It has traditionally been limited to smaller bile duct stones however. This study aimed to assess the ability of laser-assisted bile duct exploration by laparoendoscopy (LABEL) to increase the rate of successful transcystic LCBDE in patients with bile duct stones at the time of laparoscopic cholecystectomy.

Methods

Patients undergoing LCBDE between 2014 and 2018 were retrospectively analysed. Baseline demographic and medical characteristics were recorded, as well as intra-operative findings and post-procedure outcomes. Standard LCBDE via the transcystic route was initially attempted in all patients, and LABEL was only utilised if there was failure to achieve transcystic duct clearance. The transductal route was utilised for failed transcystic extraction.

Results

One hundred and seventy-nine consecutive patients underwent LCBDE; 119 (66.5%) underwent unaided transcystic extraction, 29 (16.2%) required LABEL to achieve transcystic extraction and 31 (17.3%) failed transcystic extraction (despite the use of LABEL in 7 of these cases) and hence required conversion to transductal LCBDE. As such, LABEL could be considered to increase the rate of successful transcystic extraction from 66.5% (119/179) to 82.7% (148/179). Patients requiring LABEL were however more likely to experience major complications (CD III–IV 5.6% vs 0.7%, p = 0.042) although none were specifically attributable to the laser intra-operatively.

Conclusions

LABEL is an effective adjunct to LCBDE that improves the rate of successful transcystic extraction.

Single-stage approach for the management of choledocolithiasis with concomitant cholelithiasis. Implementation of a protocol in a secondary hospital

BACKGROUND

Current evidence shows that single-stage treatment of concomitant choledocholithiasis and cholelithiasis is as effective and safe as two-stage treatment. However, several studies suggest that single-stage approach requires shorter hospitalization time and is more cost-effective than the two-stage approach, even though it requires considerable training. This study aimed to evaluate the implementation of a protocol for managing concomitant choledocholithiasis and cholelithiasis using single-stage treatment.

METHODS

A prospective cohort study of patients diagnosed with cholelithiasis and choledocholithiasis who were treated with the single-stage treatment - transcystic instrumentation, choledocotomy or intraoperative endoscopic retrograde cholangiopancreatography (ERCP) - between September 2010 and June 2017 was assessed. The primary outcomes were complications, hospital stay, operative time and recurrence rate.

RESULTS

164 patients were enrolled. 141 (86%) were operated laparoscopically. Preoperatively diagnosed stones were not found by intraoperative imaging or disappeared after "flushing" in 38 patients (23.2%). Surgical approach was transcystic in 45 patients (27.41%), choledochotomy in 74 (45.1%), intraoperative ERCP in 4 (2.4%), and bilioenteric derivation in 3 (1.8%). Mean hospitalization stay was 4.4 days. Mean operative time was 166 min 27 patients (16.5%) had complications and 1 patient was exitus (0.6%). Recurrence rate was 1.2%.

CONCLUSIONS

Single-stage approach is a safe and effective management option for concomitant cholelithiasis and choledocolithiasis. Furthermore, a significant number of common bile duct stones pass spontaneously to duodenum or can benefit from a transcystic approach, with presumable low morbidity and cost-efficiency.

Trans-infundibular choledochoscopy: a method for accessing the common bile duct in complex cases

PURPOSE

During laparoscopic common bile duct exploration (LCBDE) where Calot's triangle cannot be safely dissected due to a 'frozen' hepatic hilum secondary to severe inflammation or fibrosis, the preferred transcystic approach to the common bile duct (CBD) is precluded. The aim of this paper is to describe a safe method of accessing the CBD via a trans-infundibular approach (TIA) in complex cases where conventional access to the cystic duct or CBD is denied.

METHODS

A retrospective review of 154 consecutive patients who underwent LCBDE at a single centre between 2014 and 2018 was performed. Outcomes of this study were successful access to the CBD to achieve choledochoscopy, successful stone clearance (when required), conversion to open surgery, total or subtotal cholecystectomy, post-operative complications, and length of hospital stay.

RESULTS

Nine (5.8%) patients underwent access to the CBD via TIA choledochoscopy. TIA-LCBDE resulted in a stone extraction rate of 86% with one patient requiring choledochotomy. There were zero conversions to open surgery, and total/near total cholecystectomy was achieved in all patients. One patient suffered a post-operative complication for bilateral atelectasis and lower respiratory tract infection. Median length of hospital stay was 3 days.

CONCLUSIONS

The use of a trans-infundibular approach to the CBD is indicated when the hepatic hilum is 'frozen' with severe inflammation and/or fibrosis precluding safe dissection of the critical structures within Calot's triangle. This strategy enables exploration of the CBD via the transcystic route without the need for critical view dissection or choledochotomy.