Since its first use by Philippe Mouret in 1987, laparoscopic cholecystectomy has become the gold standard in the treatment of gallstone disease [1]. However, over the years, retrospective studies have shown that the morbidity of this laparoscopic surgery has reached a high rate compared to that known with conventional cholecystectomy, which is the main reason leading surgeons to seek the safety of the operative procedure through the implementation of systematic procedures for the prevention of s the message message finds surgical risks, even minor ones. Thus, great importance is given to the practice of intraoperative cholangiography, which ensures low biliary morbidity. CPO, performed for the first time in 1932 by Mirizzi [2], remains a subject of controversy. The debate between advocates of routine CPO and those advocating selective implementation is not new, but the advent of laparoscopy has reignited this debate, as there are some specific considerations in the laparoscopic approach, including an increased risk of iatrogenic bile duct injuries.

The theoretical benefits of CPO are numerous; it allows not only to verify the patency of the main bile duct but also to guide dissection by identifying anatomical variations and, most importantly, to detect intraoperative bile duct injuries.

The question that arises is whether a cholangiography should be performed in every cholecystectomy?

To attempt to answer this question, we conducted a prospective study involving 300 patients with gallstone disease treated with laparoscopic cholecystectomy and systematic intraoperative cholangiography.

This prospective series, conducted from 2006 to 2014, included 216 women (72%) and 84 men (28%) with a mean age of 41.6 years (ranging from 25 to 85 years). They were recruited either through outpatient consultations or admitted as emergency cases. The reasons for consultation were as follows: biliary colic (n=249), acute cholecystitis (n=31), chronic right hypochondrial pain (n=17), and atypical pain (n=3). Preoperative evaluation consisted of liver function tests and an abdominal hepatobiliary ultrasound. The main ultrasound diagnoses included simple gallstones (n=250), acute cholecystitis (n=32), and scleroatrophic gallbladder (n=18). At the end of this assessment, only patients with gallstones without signs of choledochal migration were included. All patients underwent laparoscopic cholecystectomy with systematic intraoperative cholangiography using the open laparoscopy technique. The cholangiography was performed by catheterizing the cystic duct using a vascular catheter introduced into the abdomen with the aid of a STORZ cholangiography forceps introduced by the operator's trocar, equipped with jaws to hold the vascular catheter in place. The cholangiography was carried out by dynamic fluoroscopy using a mobile surgical C-arm coupled to a scopic visualization console with an image amplifier. The duration in m Ain but Set of the cholangiography was calculated from the introduction of the catheter transcutaneously to the capture of the image. The duration in minutes of the cholangiography was calculated from the introduction of the catheter transcutaneously to the capture of the image.

The cholangiography was successfully performed in 295 patients (98.3%). In the 5 cases of failure (1.7%), the causes were related to a too narrow cystic duct in 3 cases and cystic duct obstruction due to sclerosis (scleroatrophic gallbladder) in 2 cases. Regarding the duration of on the 3rd postoperative day, he developed jaundice with an external biliary fistula from t drain. The reevaluation of the cholangiogram not reveal any bile duct injury. A laparotomy was necessary, and a recognized duodenal in was treated

minutes with an average duration of 11-55minutes. There were no complications related to the cholangiography. In our series, the presence of biliary anomalies was observed in 3 patients (1%). This involved a cystic duct that opened low, running parallel to the common bile duct, and 2 cholecysto-choledochal convergences on the left side of the common bile duct. No iatrogenic injuries to the common bile duct were recorded.

Thirteen patients (4.33%) were found to have common bile duct stones intraoperatively with no predictive factors. At the beginning of our experience, lacking adequate equipment and sufficient skills, the discovery of common bile duct stones required conversion to right subcostal laparotomy in 6 patients (46.15%). An external biliary drainage, such as the Kehr type, was quickly put in place, and we soon became convinced that treatment could be done laparoscopically. This treatment was performed on 7 patients (53.85%). Furthermore, we systematically conducted an exploration of the common bile duct using cholangioscopy. The stones were extracted using a Dormia catheter under the control of the cholangioscope, once through the transcystic route and six times through choledochotomy. An external biliary drainage was established. Patients left with the external biliary drainage, and a postoperative cholangiography was performed on day 13. There were no mortalities. Morbidity was 2%, including 2 parietal abscesses at trocar sites requiring flattening, a hemo-peritoneum due to bleeding from a trocar site, reoperated on 12 hours later, residual lithiasis treated with endoscopic sphincterotomy, and a duodenal injury that occurred during gallbladder dissection. For the duodenal injury, it involved a 42-year-old man with an uncomplicated gallbladder stone treated with laparoscopic cholecystectomy with normal common bile duct. For patients treated for common bile duct stones, the duration was 8 to 12 days.

The question of whether to perform routine intraoperative cholangiography during laparoscopic cholecystectomies remains debated. This controversy, which is not new, was reignited in the era of laparoscopy due to an abnormally high incidence of iatrogenic injuries to the main biliary tract. In the late 1980s, the frequency of biliary injuries during traditional cholecystectomy was approximately 0.15%. This rate has multiplied by 2 to 4 since the introduction of laparoscopy, especially in its early stages, with rates of 1.4% to 2.9%. Currently, the average incidence is 0.5%, but it remains higher than that occurring during laparotomy.

Thus, the most important measure is the prevention of operative injuries to the main biliary tract. Furthermore, the nature, severity, time of recognition, appropriate treatment of the injury, and the medicolegal implications all represent equally important factors that should also be specified.

Prevention from Surgery Injuries

To prevent operative injuries, the risk of these traumas has indeed become low, at 0.5% [6], but it remains non-zero. The mechanisms leading to their occurrence are multiple, and it has been demonstrated that the most common cause is the confusion between the cystic duct and the common bile duct [7]. Several authors have suggested that intraoperative cholangiography (CPO) was associated with a significant reduction in the risk of bile duct injuries [8-11], evaluating the correlation between the occurrence of injuries and the performance of CPO. They showed an inverse correlation: the more injuries, the less CPO, with Fletcher et al [12] in their Australian study, including 20,000 cholecystectomies (laparoscopic and open), demonstrating a significant protective effect of CPO. This effect was particularly pronounced in complex cholecystectomies, where injuries were eight times less likely with CPO. Flum et al [9] reported a two-fold lower rate of injuries with systematic CPO. In a national retrospective study involving over a million and a half cholecystectomies and nearly 8,000 injuries, the same   authors showed a significantly increased risk in the absence of CPO. In Ludwig's meta-analysis [10], which included 327,523 laparoscopic cholecystectomies, the injury rate was halved in the group of patients who had CPO (0.21 vs. 0.43; p < 0.05). Knowledge of any anatomical variations beforehand can guide the dissection of the cystic-choledochal region. The frequency of anomalies reported in the literature during cholangiography ranges from 1.7% to 28% [14-15]. In our series, the rate of these variations is 1%, and the failure to visualize these anomalies can lead to incorrect dissection or even accidental section of the extrahepatic bile ducts. In our experience, no injuries were recorded. Although the clear benefits of CPO are evident, some teams believe that the preventive role of CPO is not clear and remains debatable, as it does not influence the risk of bile duct injuries [16-22], and several criticisms have been raised about this.

It is necessary to interpret the results of these studies, which are often retrospective, considering the period during which the cholecystectomies were performed, with many at the beginning of the laparoscopic era. As noted by Metcalfe et al [18], few studies published in the late 1990s reported a similar frequency of injuries to the common bile duct, indicating the widespread acquisition of sufficient laparoscopic expertise. In the English literature, the use of CPO is not common, and the risk of injuries is comparable to that in centers that use it extensively. In the UK, it is systematic in 15% [23], selective in 33% of centers, and 52% of English surgeons never perform it. It is performed systematically in less than 50% of American centers [24]. CPO is not without risk; an unsuccessful attempt to perform CPO in certain cystic ducts that are thin or fragile can lead to accidental tearing. Likewise, a false image (false positive) that leads to unnecessary openings of the common bile duct can be dangerous and several allergic reactions to the contrast product have also been reported in the literature [25]. CPO cannot prevent injuries that occur after its execution due to misplacement of clips or detachment of the gallbladder from the hepatic bed [26]. Even if the common bile duct was mistaken for the common hepatic duct, CPO only identifies the trauma and its location. Anatomical anomalies in the biliary tract are ultimately rare [27,28], and currently, it is not possible to establish a clear link between the identification of these anomalies and the risk of trauma. Therefore, the best way to prevent bile duct injuries remains adhering to preoperative dissection principles, including identifying the cystic artery and the common bile duct before any cystic duct dissection [29,30]. CPO is only indicated in the presence of doubt or specific conditions (e.g., inflammatory adhesions) to achieve better orientation. Based on these arguments, it can be affirmed that CPO does not prevent all bile duct injuries but significantly reduces their incidence.

Recognizing Bile Duct Injuries

Another benefit of systematic CPO is the immediate intraoperative recognition of injuries, which is a factor in the proper management. An analysis by Ludwig et al [10] with 405 bile duct injuries showed that injuries were diagnosed twice as often in the group of cholecystectomies with routine CPO (44.5% vs. 20.1%, p < 0.05). In a Belgian experience involving 57 cases, intraoperative detection of bile duct injuries was achieved in 25% of cases in the absence of CPO and in 71% of cases with CPO. According to Archer et al [31], CPO identified 81% of bile duct injuries during the intervention. In the absence of CPO, detection was possible in only 45% of cases.

Severity of Operative Injury

Currently, it is evident that injuries occurring during cholecystectomy, whether laparoscopic with routine CPO or not, are less severe [6,10,20]. Given that the dominant mechanism of injury is the confusion between the cystic duct and the common bile duct [7], CPO allows the recognition of errors and prevents transforming a partial lateral injury into a complete section of the common bile duct. Ludwig et al [10] reported a rate of 73% of injuries in the group of patients undergoing cholecystectomy with systematic CPO. This rate drops to 14% in the case of cholecystectomy without CPO, with significantly more severe injuries in this case.

Repair of Bile Duct Injuries

Intraoperative recognition of injuries by systematic CPO, usually of lesser severity, allows for repair under favorable local operative conditions with little or no local inflammation, permitting biliary-to-biliary anastomosis. When considering operative injuries to the common bile duct, the immediate postoperative outcome was better in terms of postoperative deaths and secondary failures due to stenosis, and the best time to repair an injury is undoubtedly during the intervention itself. According to Casnedi et al [32], CPO allowed the recognition of 80% of injuries and enabled immediate repair with simple consequences. In the Belgian experience [26], immediate repair resulted in a 4% mortality rate and a 12% rate of anastomotic stenoses. In cases of late diagnosis and consequently delayed repair, the figures increased from 19% to 38%. Kullmann et al [33] recorded a long-term complication rate of approximately 25-50% in patients treated late with bilio- digestive bypass.

Screening for Asymptomatic Common Bile Duct

Gallstones has led some to question the routine use of CPO

for the detection of asymptomatic common bile duct stones [16,29,19,34,35]. They advocate its selective use in situations that increase the risk of common bile duct stones, considering preoperative and intraoperative criteria [36] that can predict 98% of cases, accepting a 2% rate of missed stones, while recognizing the possibility of spontaneous elimination of small stones in at least 50% of cases. A study [34] on the natural history of radiolucent images during routine CPO showed that 26% of the images were false positives, 26% corresponded to stones that would be spontaneously passed within six to eight weeks, and 48% corresponded to stones requiring endoscopic treatment. Thus, therapeutic decisions based on CPO findings would result in initial intervention in only 50% of cases. However, with the advent of laparoscopy on the one hand and changes in the approach to common bile duct stones in the laparoscopic era on the other, the practice of CPO has garnered renewed interest. Many teams [38,39], when deciding to perform CPO as a routine, have carefully considered a strategy for the treatment of common bile duct stones discovered intraoperatively, whether suspected or not via laparoscopy. CPO shows a better performance in detecting common bile duct stones compared to preoperative ultrasonography and intraoperative palpation (40-41) with a false positive rate of 0.6% to 2% and a false negative rate of 2%. Only laparoscopic ultrasound seems to be more sensitive but not specific [42]. Nevertheless, laparoscopic ultrasound requires specific training and expensive equipment. The approach to incidentally discovered gallstones also remains a controversial topic. Can they be ignored, subjecting the patient to the risks of future clinical manifestations and other interventions? Is it better to propose a complete biliary procedure under laparoscopy or a combined approach with endoscopic sphincterotomy? In response to the first question, it is likely that some stones can migrate silently through the papilla without symptoms, but it is impossible to predict which ones will do so and which will cause acute pancreatitis or potentially serious acute cholangitis. Hence, the systematic treatment of common bile duct stones diagnosed during CPO is justified. In our practice, the rate of common bile duct stones was 4.33%, and it seemed reasonable to treat all stones discovered during routine CPO in the course of laparoscopic cholecystectomy.

Many publications conclude that this treatment is feasible, safe, with success rates ranging from 80% to 97%, and similar mortality and morbidity rates even lower in laparoscopic surgery with less hospitalization time (43-47). In our series, laparoscopic treatment was attempted in 53.85% with satisfactory results (success rate 100%). A controlled retrospective study (48) comparing results in two approaches (complete biliary procedure under laparoscopy or secondary endoscopic sphincterotomy) for the discovery of common bile duct stones concluded that, regardless of the procedure proposed, the rate of common bile duct clearance was 75% in both groups. It was 100% in the "laparoscopic" group and 93% in the "endoscopic sphincterotomy" group. Moreover, the hospital stay was shorter in the laparoscopic group. It is evident that the "all- laparoscopic" approach is gaining ground every day, and the widespread use of systematic CPO, which requires laparoscopic skills, the availability of the cystic duct and dilated common bile duct, is the responsibility of digestive surgery educators.

Prolongation of Operative Time

One of the arguments against the routine practice of CPO is that it lengthens the operative time. Currently, the practice of CPO under fluoroscopy using high- resolution digital image amplifier support with image storage and reproduction capabilities [29] does not exceed 10 minutes. completion time of three to five minutes. In our study, the average time is also acceptable, at 11.55 minutes. Ultimately, the time spent discussing the indications for CPO should not exceed the time required for its systematic practice. Mirizzi [2] had already provided the best answer, "The only disadvantage is that it prolongs the operation, but one should not forget that in many cases, the patient's future health depends on those few minutes of waiting."

Medicolegal Aspect

 Intraoperative cholangiography is of major importance in understanding symptoms and postoperative complications through the review of images and has medicolegal significance in case of legal proceedings. Its absence or poor quality, especially if a common bile duct injury occurs, is unfavorably considered and could be viewed as a lost opportunity by the judiciary. In laparoscopic surgery, iatrogenic injuries to the biliary tract are the leading cause of legal action. A relatively recent Anglo-Saxon statistical study [50] covering all medical liability complaints in biliary surgery provides many interesting points to consider: over a period from 2000 to 2005, 208 complaints were filed following laparoscopic complications, with 133 (64%) during laparoscopic cholecystectomy alone. The most common complications were iatrogenic injuries to the biliary tract, with a rate of 72%, of which only 20% were detected intraoperatively. Regarding the legal aspect of repair, 50% of complaints with early diagnosis had a favorable outcome for the patient, compared to 90% of cases where the diagnosis was delayed.

The debate over the systematic or selective use of intraoperative cholangiography (CPO) is far from settled. Currently, the diagnostic performance of CPO appears just as reliable under laparoscopy as it was under laparotomy. In this study, CPO seemed to be a worthy consideration with a success rate of 98.3%, with no incidents related to catheterization and no bile duct injuries recorded. It revealed unsuspected common bile duct stones in 4.33% of patients. No exploration of the common bile duct, whether traditional or endoscopic, was excessive or unnecessary. Its use for the prevention of bile duct injuries is systematic. While it may not prevent all bile duct injuries, it would significantly reduce their incidence, frequency, and allow for early detection during the intraoperative period. However, there is no indication for systematic CPO to search for asymptomatic common bile duct stones, and it should be performed selectively when predictive factors for common bile duct stones are present.

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