Fluorescent cholangiography illuminating the biliary tree during laparoscopic cholecystectomy

Role of indocyanine green-guided near-infrared fluorescence imaging in identification of the cause of neonatal cholestasis

To evaluate the efficacy and safety of indocyanine green (ICG)-guided near-infrared fluorescence (NIRF) imaging during surgery to diagnose the cause of neonatal cholestasis (NC). Data on NC patients who underwent both NIRF with ICG and conventional laparoscopic bile duct exploration (the gold standard) at our institute from January 2022 to December 2022 were retrospectively analyzed. The patients' baseline characteristics and liver function outcomes were collected and analyzed, and the diagnostic consistency was compared between the 2 methods. In total, 16 NC patients were included in the study, comprising 8 (50%) male and 8 (50%) female patients, ranging in age from 42 to 93 days, with a median age of 54.4 ± 21 days. During surgery, all the patients underwent NIRF with ICG, followed by conventional laparoscopic bile duct exploration. Finally, 15 of the patients were diagnosed with biliary atresia (BA) (1 with type-I BA, and 14 with type-II BA). The other patient was diagnosed with cholestasis. The diagnostic results from fluorescence imaging with ICG were consistent with those from conventional laparoscopic bile duct exploration. ICG-guided NIRF is associated with an easy operation, less trauma, and good safety. Also, its diagnostic accuracy is similar to conventional laparoscopic bile duct exploration.

A bibliometric analysis of indocyanine green (ICG) in hepatobiliary surgery from 2008 to 2021

Hundreds of scientific documents have reported on the application of indocyanine green (ICG) in hepatobiliary surgery in the past 13 years, but few bibliometric studies have been conducted. This study aimed to identify the situations of authors, countries/regions, institutions, journals, and hot topics in this field. The overall status and prospects of the current research in this field can be elucidated by bibliometric analysis. Publications from 2008 to 2021 were retrieved from the Web of Science (WoS) Core Collection. The search terms included "liver," "hepatic," "gallbladder," "bile duct," "surgery," "hepatectomy," "ICG," "indocyanine green," and related synonyms. The full records of the search results were exported in text, and the cooperation network and hot topics were evaluated and visualized using CiteSpace software. The number of publications increased between 2008 and 2021. A total of 1527 publications were included in the results, and the frequency of citations was 30,742. The largest proportion of the publications emanated from Japan, and the majority of the papers were published by Kokudo. Tian Jie contributed the largest number of papers in China. Research was relatively concentrated among one country/region. The latest hotspots, "preservation" and "resistance", frequently occurred. Cooperation between authors, countries, and institutions needs to be strengthened for high-quality research. Recent studies have focused on hepatectomy, bile duct resection, liver transplantation, and tumors in this field. Future research may focus on other aspects, such as liver preservation and resistance.

Efficacy of different indocyanine green doses in fluorescent laparoscopic cholecystectomy: A prospective, randomized, double-blind trial

BACKGROUND AND OBJECTIVES

Intraoperative bile duct injury is a significant complication in laparoscopic cholecystectomy (LC). Near-infrared fluorescence cholangiography (NIFC) can reduce this complication. Therefore, determining the optimal indocyanine green (ICG) dosage for effective NIFC is crucial. This study aimed to determine the optimal ICG dosage for NIFC.

METHODS

This was a prospective, randomized, double-blind clinical trial at a single tertiary referral center, including 195 patients randomly assigned to three groups: lower dose (0.01 mg/BMI) ICG (n = 63), medium dose (0.02 mg/BMI) ICG (n = 68), and higher dose (0.04 mg/BMI) ICG (n = 64). Surgeon satisfaction and detection rates for seven biliary structures were compared among the three dose groups.

RESULTS

Demographic parameters did not significantly differ among the groups. The medium dose (72.1%) and higher dose ICG groups (70.3%) exhibited superior visualization of the common hepatic duct compared to the lower dose group (41.3%) (p < 0.001). No differences existed between the medium and higher dose groups. Similar trends were observed for the common bile duct and cystic common bile duct junction.

CONCLUSIONS

In patients undergoing fluorescent laparoscopic cholecystectomy, the 0.02 mg/BMI dose of indocyanine green demonstrated better biliary structure detection rates than the 0.01 mg/BMI dose and was non-inferior to the 0.04 mg/BMI dose.

Enhancing biliary structure identification using percutaneous cholecystostomy drain delivery of indocyanine green: a glowing two case review

The use of indocyanine green for fluorescent cholangiography in patients with cholecystitis initially treated with percutaneous cholecystostomy drainage catheters was described in this two case series. Two patients underwent robotic assisted cholecystectomy with fluorescent cholangiography and indocyanine green through percutaneous cholecystostomy drainage catheters. The patients were diagnosed with acute cholecystitis. Directed injection of indocyanine green allowed for direct visualization of the biliary system allowing for a safe identification of the critical view of safety. Injection of indocyanine green for fluorescent cholangiography through percutaneous cholecystostomy drainage catheters is reliable to assess the critical view of safety and allows for improved identification of the biliary tree anatomy. Administration of indocyanine green through the percutaneous cholecystostomy drainage catheters avoided background hepatic fluorescence and increased contrast between biliary structures.

Near-infrared fluorescence cholangiography in dogs: A pilot study

OBJECTIVE

To determine the effect of indocyanine green (ICG) dose and timing of administration on near-infrared fluorescence (NIRF) imaging of the normal canine biliary tree.

STUDY DESIGN

Preclinical prospective study.

ANIMALS

Eight purpose-bred beagles.

METHODS

The dogs were randomized to receive two of four intravenous ICG dose (low [L]:0.05 mg/kg or high [H]:0.25 mg/kg)/time (0 and 3 h prior to NIRF) combinations. NIRF images were collected every 10 min for 120 min. Target (cystic duct)-to-background (liver) ratios were calculated for all timepoints and compared.

RESULTS

ICG cholangiography was successful in all dogs. The contrast ratio was above 1 in the L0 group by 20 min and reached its peak at 100 min. In the H0 group, the ratio was above 1 by 60 min and reached its peak at 90 min. Contrast ratios above 2 (fluorescence twice as bright in the cystic duct compared to the liver) were maintained from 180 to 300 min for L3 and H3 and was achieved after 80 min for L0.

CONCLUSION

Low dose ICG provided better ratios early after injection compared to the high dose which remained highly concentrated in the liver tissue after injection. Both doses provided excellent visualization of the biliary tree at 3 h post injection, low dose ICG provided better ratios from 3 to 5 h post injection. Based on these results, 0.05 mg/kg of ICG administered at anesthetic premedication, or as early as 3 h prior to laparoscopic surgery should yield optimal fluorescence images.

CLINICAL SIGNIFICANCE

This study provides guidelines for NIRF cholangiography in clinically normal dogs.

Near-infrared cholangiography with intragallbladder indocyanine green injection in minimally invasive cholecystectomy

Laparoscopic cholecystectomy (LC) remains one of the most commonly performed procedures in adult and paediatric populations. Despite the advances made in intraoperative biliary anatomy recognition, iatrogenic bile duct injuries during LC represent a fatal complication and consist an economic burden for healthcare systems. A series of methods have been proposed to prevent bile duct injury, among them the use of indocyanine green (ICG) fluorescence. The most commonly reported method of ICG injection is the intravenous administration, while literature is lacking studies investigating the direct intragallbladder ICG injection. This narrative mini-review aims to assess the potential applications, usefulness, and limitations of intragallbladder ICG fluorescence in LC. Authors screened the available international literature to identify the reports of intragallbladder ICG fluorescence imaging in minimally invasive cholecystectomy, as well as special issues regarding its use. Literature search retrieved four prospective cohort studies, three case-control studies, and one case report. In the three case-control studies selected, intragallbladder near-infrared cholangiography (NIRC) was compared with standard LC under white light, with intravenous administration of ICG for NIRC and with standard intraoperative cholangiography (IOC). In total, 133 patients reported in the literature have been administered intragallbladder ICG administration for biliary mapping during LC. Literature includes several reports of intragallbladder ICG administration, but a standardized technique has not been established yet. Published data suggest that NIRC with intragallbladder ICG injection is a promising method to achieve biliary mapping, overwhelming limitations of IOC including intervention and radiation exposure, as well as the high hepatic parenchyma signal and time interval needed in intravenous ICG fluorescence. Evidence-based guidelines on the role of intragallbladder ICG fluorescence in LC require the assessment of further studies and multicenter data collection into large registries.

INDURG TRIAL Protocol: A Randomized Controlled Trial Using Indocyanine Green during Cholecystectomy in Acute Cholecystitis

INTRODUCTION

Laparoscopic cholecystectomy is one of the most common gastrointestinal surgeries, and bile duct injury is one of its main complications. The use of real-time indocyanine green fluorescence cholangiography allows the identification of extrahepatic biliary structures, facilitating the procedure and reducing the risk of bile duct lesions. A better visualization of the bile duct may help to reduce the need for conversion to open surgery, and may also shorten operating time. The main objective of this study was to determine whether the use of indocyanine green is associated with a reduction in operating time in emergency cholecystectomies. Secondary outcomes are the postoperative hospital stay, the correct intraoperative visualization of the Calot's Triangle structures with the administration of indocyanine green, and the intraoperative complications, postoperative complications and morbidity according to the Clavien-Dindo classification.

METHODS

This is a randomized, prospective, controlled, multicenter trial with patients diagnosed with acute cholecystitis requiring emergency cholecystectomy. The control group will comprise 220 patients undergoing emergency laparoscopic cholecystectomy applying the standard technique. The intervention group will comprise 220 patients also undergoing emergency laparoscopic cholecystectomy for acute cholecystitis with prior administration of indocyanine green.

CONCLUSION

Due to the lack of published studies on ICG in emergency laparoscopic cholecystectomy, this study may help to establish procedures for its use in the emergency setting.

Clinical application of indocyanine green fluorescence navigation technique in laparoscopic common bile duct exploration for complex hepatolithiasis

BACKGROUND

This study investigated the clinical application of the indocyanine green (ICG) fluorescence navigation technique in bile duct identification during laparoscopic common bile duct exploration (LCBDE) for complex hepatolithiasis.

METHODS

Eighty patients with complex hepatolithiasis were admitted to our department between January 2022 and June 2023 and randomly divided into control and observation groups. The control group underwent conventional LCBDE, while the observation group underwent LCBDE guided by ICG fluorescence.

RESULTS

Intraoperatively, the observation group had shorter operation and search times for the common bile duct (CBD), as well as reduced intraoperative blood loss and fewer complications, such as conversion to laparotomy and various injuries (gastroduodenal, colon, pancreatic, and vascular) than the control group, with statistical significance (P < 0.05). Postoperatively, the observation group had lower rates of postoperative bile leakage, abdominal infection, postoperative hemorrhage, and residual stone than the control group. Additionally, the observation group demonstrated significantly shorter times for resuming flatus, removal of the abdominal drainage tube, and hospitalization than the control group, with statistical significance (P < 0.05).

CONCLUSION

ICG fluorescence navigation technology effectively visualizes the bile duct, improves its identification rate, shortens the operation time, prevents biliary tract injury, and reduces the occurrence of complications.

The Frequency of Anatomical Variants of the Bile Ducts: A Review Based on a Single Classification as Support for Cholangiographic Examinations

Complications arising from hepatobiliary surgery can have adverse effects on both the quality of life and the survival of patients. Magnetic resonance cholangiography (MRC) techniques are highly effective at revealing anatomical variants of the bile ducts and thus play a vital role in minimizing the occurrence of complications. The aims of this review are threefold: to ascertain the classifications utilized for categorizing anatomical variants of the bile ducts, to present the reported results on the prevalence of these anatomical variants, and to explore the diagnostic modalities employed to visualize these anatomical variants and associated complications during surgical procedures. A review of the literature was carried out using the Cochrane Library database and the PubMed, Medical Literature Analysis and Retrieval System Online (MEDLINE), and Google Scholar platforms. We conducted a comprehensive review of relevant studies to categorize the different anatomical variants according to the Huang classification. According to the Huang classification, our study showed type A1, 60.44%; type A2, 11.76%; type A3, 11.73%; type A4, 5.47%; type A5, 0.26%; and type B, which was identified in insignificant numbers (0.16%) or does not appear; additionally, variants that do not fit into the Huang classification have also been identified (10.18%). The Huang classification serves as an invaluable presurgical guide, aiding in the strategic planning of biliary interventions and effectively reducing the risk of iatrogenic complications, morbidity, mortality, and postoperative length of stay. MRC is still considered the noninvasive gold standard method for evaluating the bile ducts and their anatomical variations.

Utility of indocyanine green fluorescent dye in emergency general surgery: a review of the contemporary literature

For decades, indocyanine green (ICG) has been available for medical and surgical use. The indications for ICG use in surgery have expanded where guided surgery directed by fluorescence and near-infrared fluorescent imaging offers numerous advantages. Recently, surgeons have reported using ICG operative navigation in the emergency setting, with fluorescent cholangiography being the most common procedure. The utility of ICG also involves real-time perfusion assessment, such as ischemic organs and limbs. The rising use of ICG in surgery can be explained by the ICG's rapid technological evolution, accuracy, ease of use, and great potential to guide precision surgical diagnosis and management. The review aims to summarize the current literature on the uses of ICG in emergency general surgery. It provides a comprehensive and practical summary of the use of ICG, including indication, route of administration, and dosages. To simplify the application of ICG, we subdivided its use into anatomical mapping and perfusion assessment. Anatomical mapping includes the biliary tree, ureters, and bowel. Perfusion assessment includes bowel, pancreas, skin and soft tissue, and gonads. This review provides a reference to emergency general surgeons to aid in implementing ICG in the emergency setting for more enhanced and safer patient care.

Indocyanine green (ICG) fluorescence-enhanced applications in pediatric surgery

The breadth of pediatric surgical practice and variety of anatomic anomalies that characterize surgical disease in children and neonates require a unique level of operative mastery and versatility. Intraoperative navigation of small, complex, and often abnormal anatomy presents a particular challenge for pediatric surgeons. Clinical experience with fluorescent tissue dye, specifically indocyanine green (ICG), is quickly gaining widespread incorporation into adult surgical practice as a safe, non-toxic means of accurately visualizing tissue perfusion, lymphatic flow, and biliary anatomy to enhance operative speed, safety, and patient outcomes. Experience in pediatric surgery, however, remains limited. ICG-fluorescence guided surgery is poised to address the challenges of pediatric and neonatal operations for a growing breadth of surgical pathology. Fluorescent angiography has permitted intraoperative visualization of colorectal flap perfusion for complex pelvic reconstruction and anastomotic perfusion after esophageal atresia repair, while its hepatic absorption and biliary excretion has made it an excellent agent for delineating the dissection plane in the Kasai portoenterostomy and identifying both primary and metastatic hepatoblastoma lesions. Subcutaneous and intra-lymphatic ICG injection can identify iatrogenic chylous leaks and improved yields in sentinel lymph node biopsies. ICG-guided surgery holds promise for more widespread use in pediatric surgical conditions, and continued evaluation of efficacy will be necessary to better inform clinical practice and identify where to focus and develop this technical resource.

Biliary Anatomy Visualization and Surgeon Satisfaction Using Standard Cholangiography versus Indocyanine Green Fluorescent Cholangiography during Elective Laparoscopic Cholecystectomy: A Randomized Controlled Trial

Background: Intraoperative biliary anatomy recognition is crucial for safety during laparoscopic cholecystectomy, since iatrogenic bile duct injuries represent a fatal complication, occurring in up to 0.9% of patients. Indocyanine green fluorescence cholangiography (ICG-FC) is a safe and cost-effective procedure for achieving a critical view of safety and recognizing early biliary injuries. The aim of this study is to compare the perioperative outcomes, usefulness and safety of standard intraoperative cholangiography (IOC) with ICG-FC with intravenous ICG. Methods: Between 1 June 2021 and 31 December 2022, 160 patients undergoing elective LC were randomized into two equal groups: Group A (standard IOC) and group B (ICG-FC with intravenous ICG). Results: No significant difference was found between the two groups regarding demographics, surgery indication or surgery duration. No significant difference was found regarding the visualization of critical biliary structures. However, the surgeon satisfaction and cholangiography duration presented significant differences in favor of ICG-FC. Regarding the inflammatory response, a significant difference between the two groups was found only in postoperative WBC levels. Hepatic and renal function test results were not significantly different between the two groups on the first postoperative day, except for direct bilirubin. No statistically significant difference was noted regarding 30-day postoperative complications, while none of the complications noted included bile duct injury events. Conclusions: ICG-FC presents equivalent results to IOC regarding extrahepatic biliary visualization and postoperative complications. However, more studies need to be performed in order to standardize the optimal dose, timing and mode of administration.

Indocyanine green fluorescent cholangiography: The new standard practice to perform laparoscopic cholecystectomy in pediatric patients. A comparative study with conventional laparoscopic technique

BACKGROUND

This study aimed to compare outcomes of standard laparoscopic cholecystectomy and indocyanine green fluorescent cholangiography laparoscopic cholecystectomy over a 10-year period.

METHODS

From 2013 to 2023, 173 laparoscopic cholecystectomies were performed in 2 pediatric surgery units: 83 using standard technique (G1) and 90 using indocyanine green fluorescent cholangiography (G2). Patients included 96 girls and 77 boys, with a median age of 12.3 years (range 4-17) and a median weight of 51 kg (range 19-114). The 2 groups were compared regarding the following: (1) perioperative complications rate; (2) overall length of surgery (T1); (3) length of cystic duct isolation, clipping, and sectioning (T2); (4) time of gallbladder removal (T3); (5) degree of visualization of biliary tree; (6) safety and feasibility of indocyanine green fluorescent cholangiography; (7) incidence of anatomical anomalies detected intraoperatively.

RESULTS

All laparoscopic cholecystectomies were accomplished without conversion to open. The perioperative complications rate was significantly higher in G1 compared with G2 (12% vs 0%; P = .0007). Median T1, T2, and T3 were significantly longer in G1 (90, 37, 35 minutes) compared with G2 (55, 17, 19 minutes) (P = .0001), respectively. The visualization rate of the complete biliary tree was significantly higher in G2 (98.8%) than in G1 (80.7%) (P = .0001). No adverse reactions to indocyanine green were recorded. The incidence of biliary anomalies detected intraoperatively was significantly higher in G2 (7.8%) than in G1 (1.2%) (P = .03).

CONCLUSION

Indocyanine green fluorescent cholangiography can be considered the new standard practice to perform laparoscopic cholecystectomy in pediatrics. Indocyanine green fluorescence provided superior visualization of biliary anatomy, increased detection of anatomic variants, faster procedure, and fewer complications compared with conventional technique. Indocyanine green fluorescent cholangiography was safe, feasible, simple, inexpensive, and a timesaving tool.

Near-infrared indocyanine green fluorescent cholangiography in urgent and emergency laparoscopic cholecystectomy: a preliminary study after propensity score-matched study

INTRODUCTION

Bile duct injury is a major complication of laparoscopic cholecystectomy (LC). Indocyanine green near-infrared fluorescence cholangiography (ICG-NIFC) is a well-recognized technique who provides an intraoperative mapping of the biliary system.

METHODS

All patients underwent urgent LC and randomly divided into two groups: in one group, only white light imaging was used and, in the ICG group, ICG was used. Due to the heterogeneity of our groups, a PSM was performed with a 1:1 PSM cohort.

RESULTS

The use of ICG clearly decreases the operation time (p value 0.002). The overall rate of intra- and post- operative complications was 4.17% and 15.8% respectively. Post-operative biliary duct injury trend decreases in ICG group and after the homogenization of the 2 cohorts, the intra- and post- operative complications (including vascular and biliary duct injury) results changed with a highest rate of complication in the cohort with no-ICG administration. The use of NIFC demonstrated a protective effect against intra- and post- operative complications and biliary duct injury (HR 0.037, p value 0.337 and HR 0.039, p value 0.647; HR 0.288; p value 0.05 and HR 0.635; p value 0.687, respectively).

CONCLUSIONS

The intra-operative use of NIFC showed a trend in the reduction of the rate of intra- and post-operative complications, the duration of surgery, and the length of hospital stay. ICG is a highly safe approach to urgent and emergency LC, as for elective LC, and could lead the surgeon to conduct the procedure more efficiently.

Efficacy and outcome of indocyanine green-based intraoperative cholangiography using near-infrared fluorescence imaging: A prospective study

INTRODUCTION

The most dreaded complication during laparoscopic cholecystectomy still remains to be injury to the common bile duct. The primary cause for bile duct injury during LC is misinterpretation of the biliary anatomy. Intra-operative cholangiography was introduced as a means of reducing the chances of biliary injury, done using Fluoroscopic imaging or Near-infrared fluorescence imaging method. NIRF is one of the most popular imaging methods in biomedical sciences. Indocyanine Green is sterile and water soluble which completely binds to albumin and is excreted in bile.

PATIENTS AND METHODS

This prospective study was conducted among 70 patients between July 2020 and December 2021. Subjects were administered 5mg of ICG dye pre-operatively and procedure performed using Karl Storz HD image S1 system with a D-light P light source for NIRF imaging.

RESULTS

The average duration of surgery was 58.10 minutes. After calot's dissection, the CBD was visualized in 88.71 % patients, with a mean time to visualization at 26.33 minutes. The cystic duct was visualized in 87.3% cases with a mean time of visualization of 32.10 minutes. The hepatic duct was visualized in 28.57% and the hepatic duct-CBD confluence was visualized in 34.28% patients.

CONCLUSION

Near infrared imaging based intra-operative cholangiography, using Indocyanine Green dye, during Lap. Cholecystectomy is an easy, useful and inexpensive method of visualizing the biliary ductal anatomy.

Distinguishing characteristics of xanthogranulomatous cholecystitis and gallbladder adenocarcinoma: a persistent diagnostic dilemma

BACKGROUND

Xanthogranulomatous cholecystitis (XGC) is an uncommon variant of chronic cholecystitis which can resemble gallbladder adenocarcinoma (GAC) on preoperative imaging and present technical challenges in the performance of cholecystectomy. We examined our experience with each pathology to identify distinguishing characteristics that may guide patient counseling and surgical management.

METHODS

A retrospective review of all pathologically confirmed cases of XGC and GAC following cholecystectomy between 2015 and 2021 at a single institution was performed. Clinical, biochemical, radiographic, and intraoperative features were compared.

RESULTS

There were 37 cases of XGC and 20 cases of GAC. Patients with GAC were older (mean 70.3 years vs 58.0, p = 0.01) and exclusively female (100% vs 45.9%, p < 0.0001). There were no significant differences in accompanying symptoms between groups (nausea/vomiting, fevers, or jaundice). The mean maximum white blood cell count was elevated for XGC compared to GAC (16.4 vs 8.6 respectively, p = 0.044); however, there were no differences in the remainder of the biochemical profile, including bilirubin, liver transaminases, CEA, and CA 19-9. The presence of an intraluminal mass (61.1% vs 9.1%, p = 0.0001) and lymphadenopathy (18.8%. vs 0.0%, p = 0.045) were associated with malignancy, whereas gallbladder wall thickening as reported on imaging (87.9% vs 38.9%, p = 0.0008) and gallstones (76.5% vs. 50.0%, p = 0.053) were more often present with XGC. Cases of XGC more often had significant adhesions/inflammation (83.8% vs 55.0%, p = 0.03).

CONCLUSION

Clinical features that may favor benign chronic cholecystitis over gallbladder adenocarcinoma include younger age, male gender, current or prior leukocytosis, and the absence of an intraluminal mass or lymphadenopathy. Laparoscopic cholecystectomy is a safe surgical option for equivocal presentations. Intraoperative frozen section or intentional staging of more extensive procedures based upon final histopathology are valuable surgical strategies.

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.

Fluorescence cholangiography for laparoscopic cholecystectomy: how, when, and why? A single-center preliminary study

INTRODUCTION

Bile duct injuries avoidance is a key goal of biliary surgery. In this prospective study we evaluate the safety and feasibility of ICG fluorescent cholangiography during laparoscopic cholecystectomy (LC) focusing on the optimization of timing and dose administration.

MATERIAL AND METHODS

From February to December 2022 fifty-four LC were performed with fluorescence imaging in our surgical department. 2.5 mg ICG were administered intravenously between 5 h and 24 h before surgery. Near-infrared fluorescent cholangiography (NIRF-C) was performed. Adequate fluorescence was evaluated by comparing agent accumulation in the gallbladder and the extrahepatic duct and the background of liver parenchyma.

RESULTS

Biliary anatomy was identified in all cases. Median time of ICG administration was 11 h previous surgery and three groups of patients were identified: group A receiving ICG 5-9 h, group B 10-14 h, group C 15-24 h before surgery. Peak contrast was gained in group B, with minimal fluorescence of liver parenchyma and more intense visibility of the biliary tract. Intraoperative cholangiogram was unnecessary in all cases.

CONCLUSION

Fluorescent cholangiography during LC is safe and feasible overcoming the limits of other techniques available. 2.5 mg ICG administered 10-14 h before surgery produces optimal outcomes for near-infrared (NIR) fluorescent cholangiography.

Investigation of the optimal indocyanine green dose in real-time fluorescent cholangiography during laparoscopic cholecystectomy with an ultra-high-definition 4K fluorescent system: a randomized controlled trial

This study aimed to investigate the indocyanine green (ICG) dose in real-time fluorescent cholangiography during laparoscopic cholecystectomy (LC) with a 4K fluorescent system. A randomized controlled clinical trial was conducted in patients who underwent LC for treatment of cholelithiasis. Using the OptoMedic 4K fluorescent endoscopic system, we compared four different doses of ICG (1, 10, 25, and 100 µg) administered intravenously within 30 min preoperatively and evaluated the fluorescence intensity (FI) of the common bile duct and liver background and the bile-to-liver ratio (BLR) of the FI at three timepoints: before surgical dissection of the cystohepatic triangle, before clipping the cystic duct, and before closure. Forty patients were randomized into four groups, and 33 patients were fully analyzed, with 10 patients in Group A (1 µg), 7 patients in Group B (10 µg), 9 patients in Group C (25 µg), and 7 patients in Group D (100 µg). The preoperative baseline characteristics were compared among groups (p > 0.05). Group A showed no or minimal FI in the bile duct and liver background, while Group D showed extremely high FIs in the bile duct and in the liver background at the three timepoints. Groups B and C presented with visible FI in the bile duct and low FI in the liver background. With increasing ICG doses, the FIs in the liver background and bile duct gradually increased at the three timepoints. The BLR, however, showed no increasing trend with an increasing ICG dose. A relatively high BLR on average was found in Group B, without a significant difference compared to the other groups (p > 0.05). An ICG dose ranging from 10 to 25 µg by intravenous administration within 30 min preoperatively was appropriate for real-time fluorescent cholangiography in LC with a 4K fluorescent system. Registration: This study was registered in the Chinese Clinical Trial Registry (ChiCTR No: ChiCTR2200064726).

Identification of the ideal weight-based indocyanine green dose for fluorescent cholangiography

BACKGROUND

Ideal visualization of fluorescent cholangiography during laparoscopic cholecystectomy is when maximum fluorescence into biliary ducts and absent signal into liver parenchyma, defined as "signal to background ratio" (SBR), is obtained. Such condition is mainly dependent by indocyanine green (ICG) dose and timing. The aim of this study was to identify the ideal ICG dose to obtain the best possible intraoperative visualization of the extra-hepatic biliary tree.

METHODS

The first part of the study was used to define a range of small weight-based ICG dosages using the mathematical function bisection method. During the second part of the study, the midpoint dose of the identified range, was tested in 50 consecutive cholecystectomies using a laser-based fluorescence laparoscopic camera (SynergyID system by Arthrex, Naples, FL, USA). Timing administration was set at 1 h before surgery, since this is the most common situation in clinical practice. Fluorescence intensity of bile ducts and liver parenchyma were assessed both subjectively, by blinded operative surgeon, as well as objectively, using an image analysis software (Fiji plugin), before and after Calot's triangle dissection.

RESULTS

Fourteen patients were included in the first part of the study and ICG dose between 0.01191406 and 0.0119873 mg/kg was identified. The second part confirmed previous results after testing the dosage equal to 0.0119 mg/kg (midpoint of the defined range) in 50 consecutive cholecystectomies. Cystic duct was identified in 66 and 100% of cases before and after dissection of Calot's triangle respectively. On the other hand, common bile duct was identified in 82 and 92% before and after dissection respectively. Subjective and objective SBRs confirmed the benefit of the identified ICG dose.

CONCLUSION

ICG dose calculated by 0.0119 mg/kg administered one hour before surgery allows an ideal intraoperative visualization of the extra-hepatic biliary tree.

REGISTRATION NUMBER

ISRCTN10190039.

Clinical value of fluorescent cholangiography for the infraportal type of right posterior bile duct

BACKGROUND

The infraportal type of the right posterior bile duct (infraportal RPBD) is a well-known anatomical variation that increases the potential risk of intraoperative biliary injury. The aim of this study is to clarify the clinical value of fluorescent cholangiography during single-incision laparoscopic cholecystectomy (SILC) for patients with infraportal RPBD.

MATERIAL AND METHODS

Our procedure for SILC utilized the SILS-Port, and another 5-mm forceps was inserted via an umbilical incision. A laparoscopic fluorescence imaging system developed by Karl Storz Endoskope was utilized for fluorescent cholangiography. Between July 2010 and March 2022, 41 patients with infraportal RPBD underwent SILC. We conducted retrospective reviews of patient data, focusing on the clinical value of fluorescent cholangiography.

RESULTS

Thirty-one patients underwent fluorescent cholangiography during SILC, but the remaining ten did not. Only one patient who did not undergo fluorescent cholangiography developed an intraoperative biliary injury. The detectability of infraportal RPBD before and during the dissection of Calot's triangle was 16.1% and 45.2%, respectively. These visible infraportal RPBDs were characterized as connections to the common bile duct. The confluence pattern of infraportal RPBD significantly influenced its detectability during the dissection of Calot's triangle (p < 0.001).

CONCLUSIONS

The application of fluorescent cholangiography can lead to safe SILC, even for patients with infraportal RPBD. Its benefit is emphasized when infraportal RPBD is connected to the common bile duct.

The Role of Colour Segmented Fluorescence (CSF) Mode and Same-day Administration of Low-dose Indocyanine Green in Liver Surgery: Our Initial Experience : Indocyanine Green Fluorescence Guided Resection of Liver Tumours

Indocyanine green (ICG) fluorescence image guidance (I-FIGS) is increasingly used in liver surgery. Several regimens have been described regarding the optimum timing and dose of administration. This study presents our early experience with utilising monochromatic Colour Segmented Fluorescence (CSF)-mode and same-day administration of low-dose-ICG in the resection of liver tumours. Between November 2020 and March 2022, I-FIGS was used in 15 patients with suspected liver tumours. ICG was administered intravenously at 0.02 to 0.05 mg/kg dose 2-3 h before surgery. ICG camera was switched to CSF-grey-scale mode to visualise the tumour and to avoid the interference of the green background liver. Using the SPY-CSF mode, the image was scaled to near-infra-red (NIR) fluorescence intensity to accurately identify the tumours and resection margins. Fifteen patients (eight males) with a median age of 71 years (range: 36-86) underwent I-FIGS. Of these, 67% underwent laparoscopic liver surgery, 78% had non-anatomical resections, and 33% underwent redo liver surgery. The mean tumour size was 40.6 mm (SD+/-41 mm). The median number of tumours was two (1-7). All colorectal liver metastases (CRLM) had a signet ring appearance. Hepatocellular carcinomas (HCC) showed partial fluorescence. Tumours were well/moderately differentiated, with CRLM in 86% and HCC in two patients. The R0 resection rate was 72%. In our experience, low-dose-ICG administered at least 2-3 h before surgery can identify liver tumours and their margins in CSF-grey-scale mode. Further research is needed to evaluate its role in reducing R1 resection rates and surgical outcomes.

Preoperative planning and intraoperative real-time navigation with indocyanine green fluorescence in robotic liver surgery

PURPOSE

We aimed at exploring indocyanine green (ICG) fluorescence wide spectrum of applications in hepatobiliary surgery as can result particularly useful in robotic liver resections (RLR) in order to overcome some technical limitations, increasing safety, and efficacy.

METHODS

We describe our experience of 76 RLR performed between March 2020 and December 2022 exploring all the possible applications of pre- and intraoperative ICG administration.

RESULTS

Hepatocellular carcinoma and colorectal liver metastases were the most common indications for RLR (34.2% and 26.7% of patients, respectively), and 51.3% of cases were complex resections with high IWATE difficulty scores. ICG was administered preoperatively in 61 patients (80.3%), intraoperatively in 42 patients (55.3%) and in both contexts in 25 patients (32.9%), with no observed adverse events. The most frequent ICG goal was to achieve tumor enhancement (59 patients, 77.6%), with a success rate of 94.9% and the detection of 3 additional malignant lesions. ICG facilitated evaluation of the resection margin for residual tumor and perfusion adequacy in 33.9% and 32.9% of cases, respectively, mandating a resection enlargement in 7.9% of patients. ICG fluorescence allowed the identification of the transection plane through negative staining in the 25% of cases. Vascular and biliary structures were visualized in 21.1% and 9.2% of patients, with a success rate of 81.3% and 85.7%, respectively.

CONCLUSION

RLR can benefit from the routine integration of ICG fluoresce evaluation according to each individual patient and condition-specific goals and issues, allowing liver functional assessment, anatomical and vascular evaluation, tumor detection, and resection margins assessment.

Intraoperative Imaging in Hepatopancreatobiliary Surgery

Hepatopancreatobiliary surgery belongs to one of the most complex fields of general surgery. An intricate and vital anatomy is accompanied by difficult distinctions of tumors from fibrosis and inflammation; the identification of precise tumor margins; or small, even disappearing, lesions on currently available imaging. The routine implementation of ultrasound use shifted the possibilities in the operating room, yet more precision is necessary to achieve negative resection margins. Modalities utilizing fluorescent-compatible dyes have proven their role in hepatopancreatobiliary surgery, although this is not yet a routine practice, as there are many limitations. Modalities, such as photoacoustic imaging or 3D holograms, are emerging but are mostly limited to preclinical settings. There is a need to identify and develop an ideal contrast agent capable of differentiating between malignant and benign tissue and to report on the prognostic benefits of implemented intraoperative imaging in order to navigate clinical translation. This review focuses on existing and developing imaging modalities for intraoperative use, tailored to the needs of hepatopancreatobiliary cancers. We will also cover the application of these imaging techniques to theranostics to achieve combined diagnostic and therapeutic potential.

Real-Time Fluorescent Cholangiography by Intrabiliary Indocyanine Green Administration With Near-Infrared Laparoscopy in Major Hepatectomy

BACKGROUND AND PURPOSE

Biliary injury is a severe complication that can be associated with liver surgery. Intrahepatic biliary anatomy can be evaluated using magnetic resonance cholangiopancreatography and X-ray cholangiography; however, an intraoperative real-time bile duct visualization method has not yet been reported. This study aimed to demonstrate the availability of real-time fluorescent cholangiography (FC) by intrabiliary indocyanine green administration with near-infrared laparoscopy in major hepatectomy.

METHODS

The optimal concentration of indocyanine green (ICG) solution was examined ex vivo. The fluorescence intensity of the ICG solution and its mixture with bile was measured. Using a clinical trial model, ICG solution was injected into the cystic duct, followed by near-infrared laparoscopy performed during hepatectomy.

RESULTS

The optimal concentration of ICG solution for FC was between 0.01 and 0.05 mg/mL. Three different laparoscopic systems were used in three hepatectomy cases. In all cases, the fluorescence of the intrahepatic bile ducts in the Glissonian sheath was clearly visualized using the near-infrared laparoscopic system. A small piece of tissue prevented the bile glow; thus, exposure of the Glissonian sheath was necessary for clear FC. This procedure also detected bile leakage from the cut surface of the liver.

CONCLUSIONS

Intrabiliary ICG administration and near-infrared laparoscopy enabled real-time intrahepatic FC during major hepatectomy.

Fluorescence-guided surgery: comprehensive review

BACKGROUND

Despite significant improvements in preoperative workup and surgical planning, surgeons often rely on their eyes and hands during surgery. Although this can be sufficient in some patients, intraoperative guidance is highly desirable. Near-infrared fluorescence has been advocated as a potential technique to guide surgeons during surgery.

METHODS

A literature search was conducted to identify relevant articles for fluorescence-guided surgery. The literature search was performed using Medical Subject Headings on PubMed for articles in English until November 2022 and a narrative review undertaken.

RESULTS

The use of invisible light, enabling real-time imaging, superior penetration depth, and the possibility to use targeted imaging agents, makes this optical imaging technique increasingly popular. Four main indications are described in this review: tissue perfusion, lymph node assessment, anatomy of vital structures, and tumour tissue imaging. Furthermore, this review provides an overview of future opportunities in the field of fluorescence-guided surgery.

CONCLUSION

Fluorescence-guided surgery has proven to be a widely innovative technique applicable in many fields of surgery. The potential indications for its use are diverse and can be combined. The big challenge for the future will be in bringing experimental fluorophores and conjugates through trials and into clinical practice, as well as validation of computer visualization with large data sets. This will require collaborative surgical groups focusing on utility, efficacy, and outcomes for these techniques.

Efficacy and Safety of Near-Infrared Florescence Cholangiography Using Indocyanine Green in Laparoscopic Cholecystectomy: A Systematic Review and Meta-Analysis

Background: Achieving critical view of safety is a key for a successful laparoscopic cholecystectomy (LC) procedure. Near-infrared fluorescence cholangiography using indocyanine green (NIF-ICG) in LC has been extensively used and accepted as beneficial auxiliary tool to visualize extrahepatic biliary structures intraoperatively. This study aimed to analyze its safety and efficacy. Materials and Methods: Searching for potential articles up to March 25, 2022 were conducted on PubMed, Europe PMC, and ClinicalTrials.gov databases. Articles on the near infrared fluorescence during laparoscopy cholecystectomy were collected. Review Manager 5.4 software was utilized to perform the statistical analysis. Results: Twenty-two studies with a total of 3457 patients undergo LC for the analysis. Our meta-analysis revealed that NIF-ICG technique during LC was associated with shorter operative time (Std. Mean Difference -0.86 [95% confidence interval (CI) -1.49 to -0.23], P = .007, I2 = 97%), lower conversion rate (risk ratio [RR] 0.28 [95% CI 0.16-0.50], P < .0001, I2 = 0%), higher success in identification of cystic duct (CD) (RR 1.24 [95% CI 1.07-1.43], P = .003, I2 = 94%), higher success in identification of common bile duct (CBD) (RR 1.31 [95% CI 1.07-1.60], P = .009, I2 = 90%), and shorter time to identify biliary structures (Std. Mean Difference -0.52 [95% CI -0.78 to -0.26], P < .0001, I2 = 0%) compared with not using NIF-ICG. Conclusions: NIF-ICG technique beneficial for early real-time visualization of biliary structure, shorter operative time, and lower risk of conversion during LC. Larger randomized clinical trials are still needed to confirm the results of our study.

Low vs Standard-Dose Indocyanine Green in the Identification of Biliary Anatomy Using Near-Infrared Fluorescence Imaging: A Multicenter Randomized Controlled Trial

BACKGROUND

Near-infrared fluorescence imaging using intravenous indocyanine green (ICG) facilitates intraoperative identification of biliary anatomy. We hypothesize that a much lower dose of ICG than the standard decreases hepatic and background fluorescence and improves bile duct visualization.

STUDY DESIGN

In this multicenter randomized controlled trial, 55 adult patients undergoing laparoscopic cholecystectomy were randomized to low-dose (0.05 mg) or standard-dose (2.5 mg) ICG preoperatively on the day of surgery. A quantitative assessment was performed on recorded videos from the operation using ImageJ software to quantify the fluorescence intensity of the bile duct, liver, and surrounding/background fat. Operating surgeons blinded to ICG dose provided a qualitative assessment of various aspects of the visualization of the extrahepatic biliary tree comparing near-infrared fluorescence to standard visible light imaging using a scale of 1 to 5 (1, unsatisfactory; 5, excellent). Quantitative and qualitative scores were compared between the groups to determine any significant differences between the doses.

RESULTS

The bile duct-to-liver and bile duct-to-background fat fluorescence intensity ratios were significantly higher for the low-dose group compared with the standard-dose group (3.6 vs 0.68, p < 0.0001; and 7.5 vs 3.3, p < 0.0001, respectively). Low-dose ICG had a slightly higher (ie better) mean score on the qualitative assessment compared to the standard dose, although the differences were not statistically significant.

CONCLUSIONS

Low-dose ICG leads to quantitative improvement of biliary visualization using near-infrared fluorescence imaging by minimizing liver fluorescence; this further facilitates routine use during hepatobiliary operations.

The Utility of Near-Infrared Autofluorescence for Parathyroid Gland Identification During Thyroid Surgery: A Single-Center Experience

Parathyroid gland injury during thyroid surgery is common and can lead to postoperative hypocalcemia. This study aims to determine the utility of near-infrared autofluorescence (NIRAF) technology for parathyroid gland identification in thyroid surgery. A prospective case series of patients who underwent thyroid surgery between March and June 2021 were examined. Following intra-operative visualisation, parathyroid glands and surrounding tissues were exposed to near-infrared light with a wavelength of approximately 800 nm using the Storz® Near-Infrared Range/Indocyanine Green (NIR/ICG) endoscopic system. Parathyroid glands were expected to show autofluorescence following exposure. Twenty patients who underwent thyroid surgery were included. Eighteen patients (90%) were female, with a median age of 50.0 (IQR 41.0 - 62.5). Surgeries performed include hemithyroidectomy (9 patients; 45.0%), total thyroidectomy (8 patients; 40.0%), completion thyroidectomy (2 patients; 10.0%) and right inferior parathyroidectomy (1 patient; 5.0%). Attempts were made to identify 56 parathyroid glands in this case series. There were 46/56 (82.1%) surgeon-identified parathyroid glands through direct visualisation. Using NIRAF technology, 39/46 (84.8%) were identified as parathyroid glands. There was no inadvertent resection of parathyroid glands or post-operative hypocalcaemia. NIRAF technology has the potential to be a useful tool in confirming the presence of parathyroid glands following direct visualisation intra-operatively.

Laparoscopic fluorescence imaging technique for visualizing biliary structures using sodium fluorescein: the result of a preclinical study in a porcine model

Purpose

Near-infrared fluorescence imaging has been recently applied in the field of hepatobiliary surgery. Our objective was to apply blue-light fluorescence cholangiography during laparoscopic surgery. Therefore, we designed a preclinical study to evaluate the feasibility of using blue-light fluorescence for cholangiography in a porcine model.

Methods

Five millimeters of sodium fluorescein (SF) solution was administered into the gallbladder of 20 male 3-way crossbred (Landrace × Yorkshire × Duroc) pigs in laparoscopic approach. The biliary tree was observed under blue light (a peak wavelength of 450 nm) emitted from a commercialized light-emitting diode (LED) light source (XLS1 extreme, Chammed).

Results

In 18 of 20 porcine models, immediately after SF solution was administered into the gallbladder, it was possible to visualize the biliary tree under blue light emitted from the LED light source.

Conclusion

This study provided a preclinical basis for using blue-light fluorescence cholangiography using SF in laparoscopic surgery. The clinical feasibility of blue-light fluorescence imaging techniques for laparoscopic cholecystectomy remained to be demonstrated.

Near-infrared fluorescence cholangiography assisted laparoscopic cholecystectomy (FALCON): an international multicentre randomized controlled trial

AIM

To assess the added value of Near InfraRed Fluorescence (NIRF) imaging during laparoscopic cholecystectomy.

METHODS

This international multicentre randomized controlled trial included participants with an indication for elective laparoscopic cholecystectomy. Participants were randomised into a NIRF imaging assisted laparoscopic cholecystectomy (NIRF-LC) group and a conventional laparoscopic cholecystectomy (CLC) group. Primary end point was time to 'Critical View of Safety' (CVS). The follow-up period of this study was 90 postoperative days. An expert panel analysed the video recordings after surgery to confirm designated surgical time points.

RESULTS

A total of 294 patients were included, of which 143 were randomized in the NIRF-LC and 151 in the CLC group. Baseline characteristics were equally distributed. Time to CVS was on average 19 min and 14 s for the NIRF-LC group and 23 min and 9 s for the CLC group (p 0.032). Time to identification of the CD was 6 min and 47 s and 13 min for NIRF-LC and CLC respectively (p < 0.001). Transition of the CD in the gallbladder was identified after an average of 9 min and 39 s with NIRF-LC, compared to 18 min and 7 s with CLC (p < 0.001). No difference in postoperative length of hospital stay nor occurrence of postoperative complications was found. ICG related complications were limited to one patient who developed a rash after injection of ICG.

CONCLUSION

Use of NIRF imaging in laparoscopic cholecystectomy provides earlier identification of relevant extrahepatic biliary anatomy: earlier achievement of CVS, cystic duct visualisation and visualisation of both cystic duct and cystic artery transition into the gallbladder.

Real-time fluorescent cholangiography with indocyanine green in laparoscopic cholecystectomy: a randomized controlled trial to establish the optimal indocyanine green dose within 30 min preoperatively

PURPOSE

To establish the optimal dose of indocyanine green (ICG) to administer intravenously 30 min before laparoscopic cholecystectomy (LC).

METHODS

In this randomized controlled trial (RCT), patients undergoing LC for cholecystitis, cholelithiasis, and/or cholecystic polyps were randomized into four groups given four different ICG doses (0.025, 0.1, 0.25, 2.5 mg). Using OptoMedic endoscopy combined with a near-infrared fluorescent imaging system, we evaluated the fluorescence intensity (FI) of the common bile duct and liver at three timepoints: before surgical dissection of the cystohepatic triangle, before clipping of the cystic duct, and before closure. The bile duct-to-liver ratio (BLR) of the FI was analyzed to assess the cholangiography effect.

RESULTS

Sixty-four patients were allocated to one of four groups, with 40 patients included in the final analysis. Generally, with increasing ICG doses, the levels of FI in the bile duct and liver increased gradually at each of the three timepoints. Before surgical dissection of the cystohepatic triangle, 0.1-mg ICG showed the highest BLR (F = 3.47, p = 0.0259). Before clipping the cystic duct and before closure, the 0.025- and 0.1-mg groups showed a higher BLR than the 0.25- and 2.5-mg groups (p < 0.05). When setting the ideal cholangiography at a BLR ≥ 1, ≥ 3, or ≥ 5, the 0.1-mg group showed the highest qualified case number at the three timepoints.

CONCLUSIONS

The intravenous administration of 0.1-mg ICG, 30 min before LC, is significantly better for fluorescent cholangiography of the extrahepatic biliary structures before dissection and clipping of the cystohepatic triangle.

TRIAL REGISTRATION

This study was registered in the Chinese Clinical Trial Registry (ChiCTR) (ChiCTR2200057933).

Accurate intraoperative real-time blood flow assessment of the remnant stomach during robot-assisted distal pancreatectomy with celiac axis resection using indocyanine green fluorescence imaging and da Vinci Firefly technology

INTRODUCTION

Ischemic gastropathy is one of the unique postoperative complications associated with distal pancreatectomy with celiac axis resection for locally advanced pancreatic cancer. Therefore, it is essential to evaluate blood flow to the stomach following a resection; however, no intraoperative procedures have been established to assess this issue. Herein we describe two cases in which intraoperative evaluation of real-time blood flow in the residual stomach was performed using indocyanine green fluorescence and da Vinci Firefly technology during a robot-assisted distal pancreatectomy with celiac axis resection.

METHODS

Robot-assisted distal pancreatectomy with celiac axis resection was performed using a da Vinci Xi surgical system on two patients with locally advanced pancreatic cancer and suspected invasion of the celiac artery. Indocyanine green (ICG) (0.5 mg/kg) was injected intravenously after resection to evaluate real-time blood flow of the stomach using the da Vinci Firefly system. Blood flow of the stomach was evaluated 60 seconds after the intravenous injection of ICG.

RESULTS

All cases were confirmed that there was sufficient blood flow in the residual stomach. Therefore, reconstruction of the left gastric artery was not performed, and the surgery was completed with preservation of the stomach. Good postoperative outcomes were achieved and there was no evidence of ischemic gastropathy or delayed gastric emptying in both cases.

CONCLUSION

This method is very useful in determining whether or not to perform reconstruction of the left gastric artery and/or additional resection of the remnant stomach during a robot-assisted distal pancreatectomy with celiac axis resection.

Timing of real-time indocyanine green fluorescence visualization for lymph node dissection during laparoscopic colon cancer surgery

PURPOSE

Although numerous studies have highlighted the potential value of indocyanine green (ICG) imaging in lymph node dissection of cancer surgery, its efficacy and optimal method remain to be clarified. This study aimed to investigate how lymphatic flow observation via ICG fluorescence could contribute to colon cancer surgery.

METHODS

From October 2018 to March 2021, a total of 56 patients with colon cancer who underwent laparoscopic complete mesocolic excision with intraoperative ICG imaging were analyzed. Lymphatic flow was examined at the following time points following ICG injection: within 5 min, 30-60 min, and over 60 min. We also evaluated the distribution of ICG fluorescence per each vascular pedicle.

RESULTS

Lymphatic flow was observed within 5 min following ICG injection in 6 cases (10.7%), and at 30-60 min following ICG injection in 43 cases (76.8%). ICG-stained vascular pedicles were variable especially in hepatic flexural, transverse, and splenic flexural colon cancer. Lymph node metastases were observed in 14 cases. Although metastatic lymph nodes were present only in the area along the ICG-stained vascular pedicles in 12 of the 14 cases, two patients exhibited lymph node metastasis in areas along the ICG-unstained vascular pedicles. ICG fluorescence was observed outside the standard range of lymph node dissection in 9 cases (20.9%: 9/43). Although addition of the proposed resection areas was made in 8 of these 9 cases, there was no pathologically positive lymph node.

CONCLUSION

Real-time ICG fluorescence imaging of lymph nodes may improve the performance of laparoscopic colon cancer surgery, although its oncological benefit is not yet clear.

Intra-operative indocyanine green fluorescence imaging in hepatobiliary surgery: a narrative review of the literature as a useful guide for the surgeon

INTRODUCTION

In hepatobiliary surgery, intra-operative indocyanine green (ICG) fluorescence imaging use started in the late 2000s with Japanese surgical teams and is now gaining popularity among surgeons all over the world to improve accuracy and safety of surgical procedures. However, even if ICG fluorescence has been shown to be a safe imaging modality, only a few clinical efficacity studies have been performed and no guidance has been established. This narrative review aims at assessing the potential applications of ICG fluorescence imaging in hepatobiliary surgery.

METHODS

We screened the available international literature to identify the most used applications of ICG fluorescence imaging in hepatobiliary surgery.

RESULTS

Three main fields were identified: biliary duct visualization, hepatic segments' delimitation, and liver tumor detection. Comments, application protocols, prospects, and limitations of each technique were described.

DISCUSSION

These results could guide hepatobiliary surgeons in their use of ICG fluorescence imaging; nevertheless, further prospective studies are needed to assess the sensitivity and specificity of this modality.

[Indocyanine green in liver transplantation]

The purpose of this study was to evaluate the first own experience of using indocyanine green (ICG) in liver transplantation compared to literature data and to determine its potential for clinical practice. Liver transplantation is an effective option for patients with end-stage disease, but this procedure is associated with many problems such as graft rejection, graft dysfunction, surgical risk and postoperative management. Modern methods for assessing graft function have their limitations, so a more efficient method is needed. According to this review, ICG fluorescence is valuable for effective intraoperative blood flow control, assessment of graft function, intraoperative and postoperative monitoring of clinical status. ICG fluorescence can also predict clinical status of patients at all stages of liver transplantation. Routine ICG fluorescence method is advisable in liver transplantation to improve outcomes and optimize treatment process.

Safety and usefulness of fluorescence imaging using methylene blue as a fluorophore in a Japanese population with hepatobiliary and pancreatic diseases: A phase I study

BACKGROUND

Methylene blue (MB) has been used to treat methemoglobinemia. Recently, a fluorescence imaging technique using MB as a fluorophore was used in several region but still not in hepatobiliary and pancreatic surgery; thus, information on the safety of intraoperative fluorescence imaging using MB in a healthy Japanese population is lacking. We aimed to evaluate the usefulness of MB fluorescence imaging in patients undergoing hepatobiliary and pancreatic surgery and the safety of intraoperative administration of MB in patients without methemoglobinemia.

METHODS

Eighteen patients undergoing hepatobiliary and pancreatic surgery were enrolled. We developed and used a fluorescence imaging system to visualize MB as fluorescence. The fluorescence intensity of the blood vessels, tumors, liver, and intestine were measured. The primary endpoint was the ability of the MB fluorescence imaging to visualize vessels and tumors with fluorescence. The secondary endpoint was the safety of fluorescence imaging using MB in patients without methemoglobinemia.

RESULTS

For the 18 patients undergoing MB fluorescence imaging, no intraoperative and postoperative complications related to MB administration occurred. Seventeen patients (94%) successfully visualized the target object as fluorescence by MB fluorescence imaging, including 100% of neuroendocrine tumors (four tumors) and peripancreatic vessels (n = 13).

CONCLUSION

The administration of MB and application of fluorescence imaging using MB can visualize blood vessels and pancreatic neuroendocrine neoplasms. And it also showed the safety of using MB as a fluorophore in Japanese patients without methemoglobinemia.

Fluorescence cholangiography for detection of a cystic duct drained into an accessory hepatic duct: A case report

INTRODUCTION

Laparoscopic cholecystectomy is a safe and standard procedure, but serious bile duct injury may occur due to anatomical anomalies of the biliary tract, especially the accessory hepatic duct. The use of intraoperative fluorescence cholangiography with indocyanine green during laparoscopic cholecystectomy can reportedly prevent bile duct injury.

PRESENTATION OF CASE

A 55-year-old woman with upper abdominal pain was referred to our hospital. Laboratory investigations revealed elevated leukocytes and biliary enzymes, while computed tomography demonstrated increased fatty tissue density around the gallbladder. Magnetic resonance cholangiopancreatography and drip infusion cholangiographic-computed tomography showed that the cystic duct drained into an accessory hepatic duct. Due to the diagnosis of cholelithiasis with a biliary anomaly, we performed laparoscopic cholecystectomy using fluorescence cholangiography with indocyanine green. We were able to recognize the accessory hepatic duct and cystic duct, then safely dissect the cystic duct without bile duct injury.

DISCUSSION

Laparoscopic cholecystectomy is generally regarded as a safe procedure, but complications and even mortalities can arise in patients with anatomical anomalies of the biliary tract. The aid of intraoperative fluorescence cholangiography with indocyanine green allowed to recognize and identify the accessory hepatic duct and cystic duct, allowing us to operate without injury to the bile duct.

CONCLUSIONS

Our experience supports the ease of use, safety, and effectivity of fluorescence cholangiography with indocyanine green. This may become the optimal standard technique to prevent bile duct injury.

Near-infrared fluorescence guided laparoscopic cholecystectomy in the spectrum of complicated gallstone disease

ICG fluorescence (ICGF) guidance during laparoscopic cholecystectomy (LC) is gaining wider acceptance. While the accruing data largely addresses ICGF guidance during LC in patients with uncomplicated gallstone disease (UGS) and acute cholecystitis, there is a paucity of data related for complicated gall stone disease (CGS) such as choledocholithiasis, bilio-enteric fistula, remnant gall bladder, etc. The purpose of this study was to evaluate the role of ICGF during LC in the spectrum of CGS with state of the art 4 chip camera system. Retrospective review from a prospectively maintained database of all patients who underwent ICGF guided LC during the period June 1st, 2019 till December 30th, 2021 formed part of the study. Clinical profile and findings on ICGF during LC for CGS were studied. The data was studied to evaluate the potential roles of ICGF during LC for CGS. Of 68 patients, there were 29 males and 39 females. Among them were 32 and 36 in the uncomplicated and complicated gallstone disease groups, respectively. ICGF showed CBD visualization in 67(98.5%) and cystic duct in 62(91%). ICGF guidance helped in management of CGS, prior to, during and after completion of LC. It had novel application in patients undergoing CBD exploration. In our small series of patients with CGS, ICGF guidance enabled a LC and laparoscopic subtotal cholecystectomy in 94% and 6% of patients respectively. The study highlights potential roles and advantages with ICGF guided laparoscopic management for CBD stones, bilioenteric fistula, completion cholecystectomy and cystic duct stones. Large scale multicenter prospective studies are required to clarify the role of ICGF in the wide spectrum of CGS.

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 &lt; 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.

Near-infrared fluorescence cholangiography at a very low dose of indocyanine green: quantification of fluorescence intensity using a colour analysis software based on the RGB color model

BACKGROUND

Indocyanine green (ICG) near-infrared fluorescence cholangiography (NIRF-C) is widely used to visualize the biliary tract during laparoscopic cholecystectomy (LC). However, the ICG dose and its dosing time vary in the literature so there is not a standard ICG protocol. The objectives of this descriptive prospective study were to demonstrate that NIRF-C at a very low dose of ICG provides good visualization of the extrahepatic biliary tree while avoiding hepatic hyperluminescence and to assess the surgeon-perceived benefit. Furthermore, another additional aim was quantifying the amount of ICG dye in the liver tissue and biliary tract through a green colour intensity (GCI) analysis according to red green blue (RGB) color model and correlating it to surgeon-perceived benefit.

METHOD

Forty-four patients were scheduled for LC. We recorded demographics, surgical indication, intraoperative details, adverse reactions to ICG, hepatic hyperluminescence, visualization of the cystic duct (CD), the common bile duct (CBD) and the cystic duct-bile duct junction (CDBDJ) before and after dissection of Calot's triangle, operation time, surgical complications and subjective surgeon data. For all procedures, a unique dose of 0.25 mg of ICG was administered intravenously during the anaesthetic induction. ICG NIRF-C was performed using the overlay mode of the VISERA ELITE II Surgical Endoscope in all surgeries. Video recordings of all 44 LC were reviewed. Using a color analysis software, the GCI of CBD versus adjacent liver tissue was calculated using RGB color model.

RESULTS

ICG NIRF-C was performed in all 44 cases. The mean operation time was 45 ± 15 min. There were no bile duct injuries (BDIs) or allergic reactions to ICG. The postoperative course was uneventful in all of cases. The mean postoperative hospital stay was 28 ± 4 h. ICG NIRF-C identified the CBD in 100% of the patients, the CD in 71% and the CDBDJ in 84%, with a surgeon satisfaction of 4/5 or 5/5 in almost 90% of surgeries based on a visual analogue scale (VAS). No statistically significant differences were found in the visualization of the biliary structures after the dissection of Calot's triangle in obese patients or with gallbladder inflammation. Furthermore, 25% of patients with a BMI ≥ 30, 27% of patients with a Nassar grade ≥ 3 and 21% of patients with gallbladder inflammation had a VAS score 5/5 compared to 6% of patients with a BMI < 30 (p = 0.215), 6% of patients with a Nassar grade < 3 (p = 0.083) and none of the patients without gallbladder inflammation (p = 0.037). Measured pixel GCI of CBD was higher than adjacent hepatic tissue for all cases regardless of the degree of gallbladder inflammation, the Nassar scale grades or the patient's BMI (p < 0.0001). In addition, a significant correlation was observed between surgeon-perceived benefit and the amount of ICG dye into the CBD according the RGB color model (p < 0.0001).

CONCLUSION

ICG NIRF-C at a very low dose of ICG (0.25 mg of ICG 20 min before surgery) enables the real-time identification of biliary ducts, thereby avoiding the hepatic hyperluminescence even in cases of obese patients or those with gallbladder inflammation.

Laparoscopic duodenum-preserving pancreatic head resection with real-time indocyanine green guidance of different dosage and timing: enhanced safety with visualized biliary duct and its long-term metabolic morbidity

PURPOSE

Laparoscopic duodenum-preserving pancreatic head resection (L-DPPHR) is technically demanding with extreme difficulty in biliary preservation. Only a few reports of L-DPPHR are available with alarming bile leakage, and none of them revealed the long-term metabolic outcomes. For the first time, our study explored the different dosage and timing of indocyanine green (ICG) for guiding L-DPPHR and described the long-term metabolic results.

METHODS

Between October 2015 and January 2021, different dosage and timing of ICG were administrated preoperatively and evaluated intra-operatively using Image J software to calculate the relative fluorescence intensity ratio of signal-to-noise contrast between bile duct and pancreas. Short-term complications and long-term metabolic disorder were collected in a prospectively maintained database and analyzed retrospectively.

RESULTS

Twenty-five patients were enrolled without conversion to laparotomy or pancreaticoduodenectomy. Administrating a dosage of 0.5 mg/kg 24 h before the operation had the highest relative fluorescence intensity ratio of 19.3, and it proved to guide the biliary tract the best. Fifty-six percent of patients suffered from postoperative complications with 48% experiencing pancreatic fistula and 4% having bile leakage. No one suffered from the duodenal necrosis, and there was no mortality. When compared with the non-ICG group, the ICG group had a comparable diameter of tumor and similar safety distance from lesions to common bile duct; however, it decreased the incidence of bile leakage from 10% to none. The median length of hospital stay was 16 days. After a median follow-up of 26.6 months, no one had tumor recurrence or refractory cholangitis. No postoperative new onset of diabetes mellitus (pNODM) was observed, while pancreatic exocrine insufficiency (pPEI) and non-alcoholic fatty liver disease (NAFLD) were seen in 4% of patients 12 months after the L-DPPHR.

CONCLUSION

L-DPPHR is feasible and safe in selected patients, and real-time ICG imaging with proper dosage and timing may greatly facilitate the identification and the prevention of biliary injury. And it seemed to be oncological equivalent to PD with preservation of metabolic function without refractory cholangitis.

Navigated liver surgery: State of the art and future perspectives

BACKGROUND

In recent years, the development of digital imaging technology has had a significant influence in liver surgery. The ability to obtain a 3-dimensional (3D) visualization of the liver anatomy has provided surgery with virtual reality of simulation 3D computer models, 3D printing models and more recently holograms and augmented reality (when virtual reality knowledge is superimposed onto reality). In addition, the utilization of real-time fluorescent imaging techniques based on indocyanine green (ICG) uptake allows clinicians to precisely delineate the liver anatomy and/or tumors within the parenchyma, applying the knowledge obtained preoperatively through digital imaging. The combination of both has transformed the abstract thinking until now based on 2D imaging into a 3D preoperative conception (virtual reality), enhanced with real-time visualization of the fluorescent liver structures, effectively facilitating intraoperative navigated liver surgery (augmented reality).

DATA SOURCES

A literature search was performed from inception until January 2021 in MEDLINE (PubMed), Embase, Cochrane library and database for systematic reviews (CDSR), Google Scholar, and National Institute for Health and Clinical Excellence (NICE) databases.

RESULTS

Fifty-one pertinent articles were retrieved and included. The different types of digital imaging technologies and the real-time navigated liver surgery were estimated and compared.

CONCLUSIONS

ICG fluorescent imaging techniques can contribute essentially to the real-time definition of liver segments; as a result, precise hepatic resection can be guided by the presence of fluorescence. Furthermore, 3D models can help essentially to further advancing of precision in hepatic surgery by permitting estimation of liver volume and functional liver remnant, delineation of resection lines along the liver segments and evaluation of tumor margins. In liver transplantation and especially in living donor liver transplantation (LDLT), 3D printed models of the donor's liver and models of the recipient's hilar anatomy can contribute further to improving the results. In particular, pediatric LDLT abdominal cavity models can help to manage the largest challenge of this procedure, namely large-for-size syndrome.

Robot-assisted liver resection: the real benefit so far

BACKGROUND

Minimally invasive liver resection is associated with lower perioperative morbidity and shorter hospital stay. However, the added benefit of the robotic platform over conventional laparoscopy is a matter of ongoing investigation.

PURPOSE

The purpose of this narrative review is to provide an up-to-date and balanced evaluation of the benefits and shortcomings of robotic liver surgery for the modern hepatobiliary surgeon.

CONCLUSIONS

Advantages of a robotic approach to liver resection include a shortened learning curve, the ability to complete more extensive or complex minimally invasive operations, and integrated fluorescence guidance. However, the robotic platform remains limited by a paucity of parenchymal transection devices, complete lack of haptic feedback, and added operating time associated with docking and instrument exchange. Like laparoscopic hepatectomy, robotic hepatectomy may provide patients with more rapid recovery and a shorter hospital stay, which can help offset the substantial costs of robot acquisition and maintenance. The oncologic outcomes of robotic hepatectomy appear to be equivalent to laparoscopic and open hepatectomy for appropriately selected patients.

Study of Learning Curve in a Surgeon for Near-Infrared Fluorescence Cholangiography During Laparoscopic Cholecystectomy-A Retrospective Evaluation

BACKGROUND

Near-infrared indocyanine green fluorescence cholangiography (NIRF) has shown promising results on delineating extra-hepatic biliary anatomy during laparoscopic cholecystectomy to avoid bile duct injury. However its routine usage remains in question. In this study, the technique was evaluated further with learning curve estimation and learning factors were observed.

METHODS

One hundred ninety-nine cases which underwent laparoscopic cholecystectomy for acute or chronic cholecystitis within a 2-year period including 51 cases with initial use of NIRF by 2 surgeons were studied retrospectively. The learning curve was evaluated for a surgeon as primary objective. A case-matched comparison of the operative time between NIRF and conventional group, in terms of acute and chronic cholecystitis was also conducted as a secondary calculation.

RESULTS

Learning curve was evaluated with 61% learning rate for NIRF experience. Cysto-biliary junction non-illuminated cases under fluorescent view, had mean operative time of 80.83 ± 22.82 min, which was shorter than the cysto-biliary junction illuminated cases. The NIRF group exhibited longer operative time compared with the conventional group with mean difference of 34.39 min (significant at P < .05).

CONCLUSIONS

While the initial learning phase might be affected by surgeons' behavior and attitude, our results may provide a reference to learn at one's own pace and to employ NIRF teaching strategies during surgical training programs to overcome the initial phase during training period itself and facilitate universal achievement.

Routine use of ICG to enhance operative safety in emergency laparoscopic cholecystectomy: a randomized controlled trial

OBJECTIVE

To test the hypothesis that ICG fluorescence cholangiography (ICG-FC) helps to identify critical structures during laparoscopic cholecystectomy (LC) and hence reduce biliary injuries and conversions. In LC, biliary injury and conversion often happen if the biliary anatomy is misidentified.

METHODS

This was a single-center randomized controlled trial from 2017 to 2019. Patients with acute cholecystitis requiring LC were assessed for eligibility for the trial. Patients in the trial were randomized to undergo either conventional LC (conventional arm) or LC with ICG-FC (ICG arm). Conversion rate and biliary injury incidence were outcome measures.

RESULTS

Totally 92 patients participated (46 patients in each arm). The median age was 61 years in both arms (p = 0.472). The conventional arm had 22 men and 24 women; the ICG arm had 24 men and 22 women (p = 0.677). The two arms were comparable in all perioperative parameters. The time from ICG injection to surgery was 67 (16-1150) min. Both arms had an 8.7% conversion rate (p = 1.000). The median operative time was 140.5 min in the conventional arm and 149.5 min in the ICG arm (p = 0.086). The complication rate was 15.2% in the former and 10.9% in the latter (p = 0.536), and both had a 2.2% bile leakage rate. The median hospital stay was 3.5d in the former and 4.0d in the latter (p = 0.380).

CONCLUSION

ICG-FC did not make any difference in conversion or complication rate. Its routine use in LC is questionable. However, it may be helpful in difficult cholecystectomies and may be used as an adjunct.

TRIAL REGISTRATION

The trial was registered with the Institutional Review Board of University of Hong Kong/Hospital Authority Hong Kong West Cluster ( http://www.med.hku.hk/en/research/ethics-and-integrity/human-ethics ). Registration number: UW17-492.

Global trends of indocyanine green fluorescence navigation in laparoscopic cholecystectomy: bibliometrics and knowledge atlas analysis

BACKGROUND

Indocyanine green fluorescence cholangiography is a new type of cholangiography that has emerged in recent years. It has many advantages, such as simplicity, safety, and efficiency, and is expected to become a routine procedure for intraoperative cholangiography in the future. However, there is no bibliometric analysis of horizontal generalization in this field. Therefore, this study aims to assess the current research status and developmental trends in this field from a global perspective and to help guide the focus of future research.

METHODS

This study was conducted by retrieving the literature related to ICG fluorescence cholangiography published in English from 2000 to 2021 from Web of Science. The Histcite. Pro tool was used to analyze the bibliometric indicators, and VOSviewer was used to visualize the research trends and hotspots in this field.

RESULTS

192 related studies were finally included. For the past 20 years, the number of related publications in this field have increased yearly, with 2010 being a breakthrough point for research in this field. Research has developed rapidly since 2013 and may continue to expand in the next several years. The USA and Japan play leading roles in this field. "SURG ENDOSC", "SURG INNOV", and "J LAPAROENDOSC ADV S" are core journals that publish high-quality literature and the latest developments in this field. Some authors who have a large number of high-quality publications include Ishizawa T and Kokudo N. The current research hotspots in this field are focused on exploring the factors that affect ICG cholangiography and optimization measures.

CONCLUSIONS

In general, the number of documents related to ICG fluorescence cholangiography is growing rapidly, with the USA and Japan being influential countries and China being one of the major producers of these documents. The optimization of this new technology will affect key developments in future research.