The Use of Fluorescence Angiography During Laparoscopic Sleeve Gastrectomy

Use of Indocyanine Green to Detect Intraoperative Staple-Line Leaks in Robotic Bariatric Surgery: An Observational Cohort Study

Background Bariatric surgeries aid weight loss in patients with morbid obesity, yet staple-line leaks pose safety concerns. Multiple methods are used to help identify these links. Intraluminal indocyanine green (ICG) has been shown to be useful in other applications, and its use in robotic bariatric surgeries is underexplored. Objective The primary objective of this research project was to demonstrate the usage of intraluminal ICG in detecting staple-line leaks during robotic sleeve gastrectomy and robotic gastric bypass. Settings The research was conducted at Bronxcare Health System between June 2022 and June 2023. Methods We studied 150 consecutive participants undergoing robotic sleeve gastrectomy or robotic gastric bypass. Intraluminal ICG was used in each case in order to identify leaks. Data on comorbidities, detected intraoperative leaks, and detected postoperative leaks were collected. Results Out of the 150 patients who underwent robotic bariatric surgeries (139 for sleeve gastrectomy and 11 for gastric bypass), four cases (two for each procedure) were identified with intraoperative leaks using ICG, resulting in an overall 2.66% incidence rate. In those four patients with intraoperative leaks, reinforcing sutures and a drain were placed. Following the surgeries, none of the patients had radiologic or clinical leaks identified. Conclusions Intraluminal ICG presents a novel approach for detecting staple-line leaks in robotic bariatric surgery. Future studies can be done to look at a larger series of patients and compare leak detection rates between ICG and other methods.

Current applications of indocyanine green (ICG) in abdominal, gynecologic and urologic surgery: a meta-review and quality analysis with use of the AMSTAR 2 instrument

BACKGROUND

Indocyanine green (ICG) is an injectable fluorochrome that has recently gained popularity as a means of assisting intraoperative visualization during laparoscopic and robotic surgery. Many systematic reviews and meta-analyses have been published. We conducted a meta-review to synthesize the findings of these studies.

METHODS

PubMed and Embase were searched to identify systematic reviews and meta-analyses coping with the uses of ICG in abdominal operations, including Metabolic Bariatric Surgery, Cholecystectomy, Colorectal, Esophageal, Gastric, Hepato-Pancreato-Biliary, Obstetrics and Gynecology (OG), Pediatric Surgery, Surgical Oncology, Urology, (abdominal) Vascular Surgery, Adrenal and Splenic Surgery, and Interdisciplinary tasks, until September 2023. We submitted the retrieved meta-analyses to qualitative analysis based on the AMSTAR 2 instrument.

RESULTS

We identified 116 studies, 41 systematic reviews (SRs) and 75 meta-analyses (MAs), spanning 2013-2023. The most thoroughly investigated (sub)specialties were Colorectal (6 SRs, 25 MAs), OG (9 SRs, 15 MAs), and HPB (4 SRs, 12 MAs). Interestingly, there was high heterogeneity regarding the administered ICG doses, routes, and timing. The use of ICG offered a clear benefit regarding anastomotic leak prevention, particularly after colorectal and esophageal surgery. There was no clear benefit regarding sentinel node detection after OG. According to the AMSTAR 2 tool, most meta-analyses ranked as "critically low" (34.7%) or "low" (58.7%) quality. There were only five meta-analyses (6.7%) that qualified as "moderate" quality, whereas there were no "high" quality reviews.

CONCLUSIONS

Regardless of the abundance of pertinent literature and reviews, surgeons should be cautious when interpreting their results on ICG use in abdominal surgery. Future reviews should focus on ensuring methodological vigor; establishing clear protocols of ICG dose, route of administration, and timing; and improving reporting quality. Other sources of data (e.g., registries) and novel methods of data analysis (e.g., machine learning) might also contribute to an enhanced role of ICG as a decision-making tool in surgery.

Indocyanine Green in Bariatric Surgery: a Systematic Review

Indocyanine green (ICG) is a fluorescent dye that can be used intraoperatively to assess tissue perfusion, as well as perform leak testing. This study aims to summarize published manuscripts on outcomes of ICG use and reduction of complications compared to traditional leak test and tissue perfusion evaluation. A PubMed search using "ICG and bariatric surgery," "ICG and gastric sleeve," "ICG and gastric bypass," and "ICG and revisional bariatric surgery" was performed. The proportion of patients who underwent an intraoperative decision change due to ICG was 3.8% (95% CI: 2.0 to 7.2%). ICG fluorescent imaging in bariatric surgery is a valuable tool, and further studies are needed to confirm its utility for routine use in both standard or complex cases (PROSPERO #418126).

Use of quantitative indocyanine green near-infrared fluorescence imaging in bariatric surgery: early results

INTRODUCTION

Indocyanine green fluorescence angiography (ICG-FA) is commonly used in general surgery, but its use in bariatric surgery is still marginal. Moreover, post-operative leaks remain a dramatic complication after this surgery and the leak tests available have poor performance preventing them. The aim of the present paper is to assess the use and utility of a new innovative technology based on quantitative measures of fluorescence signal intensity.

MATERIAL AND METHODS

From January 2022 to June 2022, 40 consecutive patients with a median age of 51 years and a preoperative median body mass index of 45.2 kg/m2 underwent bariatric surgery with quantitative ICG fluorescence angiography in our center. Two different types of surgery, based on the multidisciplinary evaluation, were performed: laparoscopic sleeve gastrectomy (LSG) and one anastomosis gastric bypass (OAGB). For ICG visualization, quantitative laparoscopic ICG platform was used to identify the vascular supply.

RESULTS

Thirteen patients underwent LSG and 27 patients underwent OAGB. ICG was performed in all patients with no adverse events. An adequate and satisfactory blood supply was assessed in each case. No case of post-operative leak was detected.

CONCLUSIONS

The quantitative ICG-FA seems to be a useful and promising tool for the prevention of complications in bariatric surgery but further studies are mandatory.

Use real-time near-infrared fluorescence during Heller's cardiomyotomy for achalasia cardia

Laparoscopic Heller's cardiomyotomy is the surgical procedure of choice in the management of oesophageal achalasia. It is critical to confirm the completeness of the myotomy and mucosal integrity at the conclusion of the procedure. This is conventionally achieved by intraoperative endoscopy and dynamic air leak test. Other modalities that can be used to confirm the myotomy and the integrity of the mucosa at the myotomy site are oesophageal manometry and a methylene blue dye study, respectively. Indocyanine green (ICG) has been in clinical use for more than six decades. The real-time integration of ICG fluorescence with laparoscopy is a relatively new breakthrough. Here, we present a novel method of using real-time near-infrared ICG fluorescence for confirming the completeness of the myotomy and mucosal integrity at the myotomy site post laparoscopic Heller's myotomy. This is the first report on the use of ICG in laparoscopic Heller's cardiomyotomy that we are aware of.

Assessment of gastric pouch blood supply with indocyanine green fluorescence in conversional and revisional bariatric surgery: a prospective comparative study

Our study aimed to evaluate the usefulness of indocyanine green (ICG) angiography during conversional or revisional bariatric surgery. We prospectively enrolled all patients scheduled for reoperative bariatric surgery with gastric pouch resizing and ICG assessment and we compared them with a retrospective series of similar patients who did not receive ICG. The primary outcome was the rate of intraoperative change in the surgical strategy due to the ICG test. We included 32 prospective patients receiving intraoperatively an ICG perfusion test and 48 propensity score-matched controls. The mean age was 50.7 ± 9.7 years, 67 (83.7%) patients were female, and the mean BMI was 36.8 ± 5.3 kg/m2. The patient characteristics were similar in both groups. The ICG angiography was successfully conducted in all patients, and no change of the surgical strategy was necessary. Postoperative complications were similar in both groups (6.2% vs. 8.3%, p = 0.846), as well as operative time (125 ± 43 vs. 133 ± 47 min, p = 0.454) and length of hospital stay (2.8 ± 1.0 vs. 3.3 ± 2.2 days, p = 0.213). Our study suggested that ICG fluorescence angiography might not have been useful for assessing the blood supply of the gastric pouch in patients who underwent reoperative bariatric surgery. Therefore, it remains uncertain whether the application of this technique is indicated.

European Association for Endoscopic Surgery (EAES) consensus on Indocyanine Green (ICG) fluorescence-guided surgery

BACKGROUND

In recent years, the use of Indocyanine Green (ICG) fluorescence-guided surgery during open and laparoscopic procedures has exponentially expanded across various clinical settings. The European Association of Endoscopic Surgery (EAES) initiated a consensus development conference on this topic with the aim of creating evidence-based statements and recommendations for the surgical community.

METHODS

An expert panel of surgeons has been selected and invited to participate to this project. Systematic reviews of the PubMed, Embase and Cochrane libraries were performed to identify evidence on potential benefits of ICG fluorescence-guided surgery on clinical practice and patient outcomes. Statements and recommendations were prepared and unanimously agreed by the panel; they were then submitted to all EAES members through a two-rounds online survey and results presented at the EAES annual congress, Barcelona, November 2021.

RESULTS

A total of 18,273 abstracts were screened with 117 articles included. 22 statements and 16 recommendations were generated and approved. In some areas, such as the use of ICG fluorescence-guided surgery during laparoscopic cholecystectomy, the perfusion assessment in colorectal surgery and the search for the sentinel lymph nodes in gynaecological malignancies, the large number of evidences in literature has allowed us to strongly recommend the use of ICG for a better anatomical definition and a reduction in post-operative complications.

CONCLUSIONS

Overall, from the systematic literature review performed by the experts panel and the survey extended to all EAES members, ICG fluorescence-guided surgery could be considered a safe and effective technology. Future robust clinical research is required to specifically validate multiple organ-specific applications and the potential benefits of this technique on clinical outcomes.

Indocyanine green (ICG) fluorescence guide for the use and indications in general surgery: recommendations based on the descriptive review of the literature and the analysis of experience

Indocyanine Green is a fluorescent substance visible in near-infrared light. It is useful for the identification of anatomical structures (biliary tract, ureters, parathyroid, thoracic duct), the tissues vascularization (anastomosis in colorectal, esophageal, gastric, bariatric surgery, for plasties and flaps in abdominal wall surgery, liver resection, in strangulated hernias and in intestinal ischemia), for tumor identification (liver, pancreas, adrenal glands, implants of peritoneal carcinomatosis, retroperitoneal tumors and lymphomas) and sentinel node identification and lymphatic mapping in malignant tumors (stomach, breast, colon, rectum, esophagus and skin cancer). The evidence is very encouraging, although standardization of its use and randomized studies with higher number of patients are required to obtain definitive conclusions on its use in general surgery. The aim of this literature review is to provide a guide for the use of ICG fluorescence in general surgery procedures.

Indocyanine Green Fluorescence Angiography During Laparoscopic Bariatric Surgery: A Pilot Study

Aims

Indocyanine green (ICG) fluorescence angiography (FA) is used for several purposes in general surgery, but its use in bariatric surgery is still debated. The objective of the present pilot study is to evaluate the intraoperative utility of ICG-FA during bariatric surgery in order to focus future research on a reliable tool to reduce the postoperative leak rate.

Methods

Thirteen patients (4 men, 30.8%, 9 women, 69.2%) with median age of 52 years (confidence interval, CI, 95% 46.2–58.7 years) and preoperative median body mass index of 42.6 kg/m² (CI, 95% 36 to 49.3 kg/m²) underwent bariatric surgery with ICG-FA in our center. Three mL of ICG diluted with 10 cc sterile water were intravenously injected after gastric tube creation during laparoscopic sleeve gastrectomy (LSG) and after the gastric pouch and gastro-jejunal anastomosis creation during laparoscopic gastric by-pass (LGB). For the ICG-FA, Karl Storz Image 1S D-Light system (Karl Storz Endoscope GmbH & C. K., Tuttlingen, Germany) placed at a fixed distance of 5 cm from the structures of interest and zoomed vision modality were used to identify the vascular supply. The perfusion pattern was assessed by the surgical team according to a score. The score ranged from 1 (poor vascularization) to 5 (excellent vascularization) based on the intensity and timing of fluorescence of the vascularized structures.

Results

Fom January 2021 to February 2022, six patients underwent LSG (46.2%), three patients underwent LGB (23.1%), and four patients underwent re-do LGB after LSG (30.8%). No adverse effects to ICG were observed. In 11 patients (84.6%) ICG-FA score was 5. During two laparoscopic re-do LGB, the vascular supply was not satisfactory (score 2/5) and the surgical strategy was changed based on ICG-FA (15.4%). At a median follow-up of five months postoperatively, leaks did not occur in any case.

Conclusions

ICG-FA during bariatric surgery is a safe, feasible and promising procedure. It could help to reduce the ischemic leak rate, even if standardization of the procedure and objective fluorescence quantification are still missing. Further prospective studies with a larger sample of patients are required to draw definitive conclusions.

Leak after sleeve gastrectomy with positive intraoperative indocyanine green test: Avoidable scenario?

Background

The staple line gastric leak (GL) is estimated to be the most serious complication of the sleeve gastrectomy. The use of indocyanine green (ICG) has been introduced in minimally invasive surgery to show the vascularization of the stomach in real time and its application to the gastroesophageal junction (GE) during Laparoscopic Sleeve Gastrectomy (LSG) seems very promising.

Case presentation

We present the case of a 40-year-old female underwent laparoscopic sleeve gastrectomy. Intraoperative indocyanine green test showed a small dark area in the proximal third of the staple line reinforced with fibrin glue. Two weeks later the patient presented to the emergency room (ED) with abdominal pain, fever, vomiting, intolerance to oral intake and the evidence of a leak on the abdomen Computer Tomography (CT). The UIN for ClinicalTrial.gov Protocol Registration and Results System is: NCT05337644 for the Organization UFoggia.

Conclusions

This case report shows that intraoperative ICG test can be helpful in determining which patients are at greater risk of the leak and, more importantly, the cause of the leak but further tests are needed to determine if the ICG predicts leak due to ischemia.

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Fistulas after sleeve gastrectomy are complex and have multifactorial origins.

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Indocyanine Green (ICG) is a liquid that can be injected into the human bloodstream without adverse effects.

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This is a case report of a 40-year-old female with a positive intraoperative indocyanine green test as a prediction of the leak after sleeve gastrectomy.

Could fluorescence-guided surgery be an efficient and sustainable option? A SICE (Italian Society of Endoscopic Surgery) health technology assessment summary

BACKGROUND

Indocyanine green fluorescence vision is an upcoming technology in surgery. It can be used in three ways: angiographic and biliary tree visualization and lymphatic spreading studies. The present paper shows the most outstanding results from an health technology assessment study design, conducted on fluorescence-guided compared with standard vision surgery.

METHODS

A health technology assessment approach was implemented to investigate the economic, social, ethical, and organizational implications related to the adoption of the innovative fluorescence-guided view, with a focus on minimally invasive approach. With the support of a multidisciplinary team, qualitative and quantitative data were collected, by means of literature evidence, validated questionnaires and self-reported interviews, considering the dimensions resulting from the EUnetHTA Core Model.

RESULTS

From a systematic search of literature, we retrieved the following studies: 6 on hepatic, 1 on pancreatic, 4 on biliary, 2 on bariatric, 4 on endocrine, 2 on thoracic, 11 on colorectal, 7 on urology, 11 on gynecology, 2 on gastric surgery. Fluorescence guide has shown advantages on the length of hospitalization particularly in colorectal surgery, with a reduction of the rate of leakages and re-do anastomoses, in spite of a slight increase in operating time, and is confirmed to be a safe, efficacious, and sustainable vision technology. Clinical applications are still presenting a low evidence in the literature.

CONCLUSION

The present paper, under the patronage of Italian Society of Endoscopic Surgery, based on an HTA approach, sustains the use of fluorescence-guided vision in minimally invasive surgery, in the fields of general, gynecologic, urologic, and thoracic surgery, as an efficient and economically sustainable technology.

Intra-arterial versus negative-staining of embryonal resection borders with indocyanine green (ICG) fluorescence for total mesorectal excision in colorectal cancer - an experimental feasibility study in a porcine model

Background: Colorectal cancer (CRC) is one of the most common malignancies worldwide. Laparoscopic lower rectal resections in accordance with the oncological principles are recommended as the gold standard for CRC surgical management. However, the learning curve for adopting these techniques is quite steep and the incomplete resections are predictive of local recurrence. This study was conducted in an attempt to find a way to help surgeons to overcome some of these difficulties and define the right resection margins.Material and methods: As such, we carried out two laparoscopic lower rectal resections in porcine models. The first resection was performed following the ligation and selective infusion of Indocyanine Green (ICG) into the inferior mesenteric artery (IMA), and the second after the ligation of both inferior mesenteric artery and vein (IMV) and systemic intravenous infusion of ICG. Fluorescence was detected in real time by means of an infrared imaging system.Results: Sharp resection margins were defined after intra-arterial infusion, and all the tissues in the IMA basin were colored in the first case. In the second model every organ and tissue was colored except the rectum, urinary bladder and ductus deferens.Conclusions: Although systemic intra-venous application of ICG and negative-staining of the rectum including the mesorectum is much easier compared to laparoscopic inter-arterial perfusion through IMA, image results of selevtive IMA-perfusion appear in sharper discrimination of the several layers. Further investigation should focus on simplifying this technique.

Near-Infrared-Fluorescent Erythrocyte-Mimicking Particles: Physical and Optical Characteristics

Exogenous fluorescent materials activated by near-infrared (NIR) light can offer deep optical imaging with subcellular resolution, and enhanced image contrast. We have engineered NIR particles by doping hemoglobin-depleted erythrocyte ghosts (EGs) with indocyanine green (ICG). We refer to these optical particles as NIR erythrocyte-mimicking transducers (NETs). A particular feature of NETs is that their diameters can be tuned from micrometer to nanometer scale, thereby, providing a capability for broad NIR biomedical imaging applications. Herein, we investigate the effects of ICG concentration on key material properties of micrometer-sized NETs, and nanometer-sized NETs fabricated by either sonication or mechanical extrusion of EGs. The zeta potentials of NETs do not vary significantly with ICG concentration, suggesting that ICG is encapsulated within NETs regardless of particle size or ICG concentration. Loading efficiency of ICG into the NETs monotonically decreases with increasing values of ICG concentration. Based on quantitative analyses of the fluorescence emission spectra of the NETs, we determine that 20 μM ICG utilized during fabrication of NETs presents an optimal concentration that maximizes the integrated fluorescence emission for micrometer- and nanometer-sized NETs. Encapsulation of the ICG in these constructs also enhances the fluorescence stability and quantum yield of ICG. These results guide the engineering of NETs with maximal NIR emission for imaging applications such as fluorescence-guided tumor resection and real-time angiography.