Usefulness of blood supply visualization by indocyanine green fluorescence for reconstruction during esophagectomy

Indocyanine Green Fluorescence Angiography Versus Visual Assessment for Assessing Perfusion of Gastric Conduit and Esophageal Stump in Post Esophagectomy Patients: A Pilot Randomized Controlled Study

BACKGROUND AND OBJECTIVE

Anastomotic leak (AL) is a serious complication following esophagectomy and is often linked to poor perfusion of the gastric conduit (GC) and esophageal stump (EC). The aim of this study is to compare the efficacy of intraoperative Indocyanine green fluorescence angiography (ICG-FA) versus visual assessment VA) to assess perfusion status and its impact on the rate of AL.

METHODS

Fifty-eight esophageal or gastroesophageal junction carcinoma patients were randomized to ICG-FA (28) and VA (30) groups. Perfusion status was assessed with VA alone in the VA group and with VA followed by ICG-FA in the ICG-FA group.

RESULTS

The ICG-FA group had a lower leak rate of 4% when compared to 27% in the VA group (p = 0.03). ICG-FA identified nine cases where VA misjudged the GC tip vascularity, thereby avoiding unnecessary resections. ICG-FA necessitated revision of the GC tip in one case missed by VA and also identified poor perfusion of ES tip in three cases mandating revision which were deemed well-perfused by VA.

CONCLUSION

ICG-FA demonstrated superiority over VA in assessing perfusion adequacy of the GC and ES, which resulted in a statistically significant decrease in the rate of anastomotic leaks.

Single-Port Robot-Assisted Minimally Invasive Esophagectomy Using the Single-Port Robotic System via the Subcostal Approach: A Single-Center Retrospective Study

BACKGROUND

Robot-assisted minimally invasive esophagectomy (RAMIE) has gained global popularity. Recent randomized controlled trials have demonstrated that RAMIE results in reduced operative times and a greater number of dissected lymph nodes compared to conventional minimally invasive esophagectomy (MIE). This study provides an initial analysis of single-port (SP) robot-assisted minimally invasive esophagectomy (SRAMIE) using the SP robotic system via the subcostal approach. The primary objective is to examine perioperative outcomes of SRAMIE compared to multi-port RAMIE (MRAMIE) using the Xi robotic system and video-assisted thoracoscopic esophagectomy (VAE).

METHODS

In this retrospective study, patients who underwent MIE at a single center between February 2017 and December 2024 were analyzed. Patients were divided into SRAMIE (n = 17), MRAMIE (n = 13), and VAE (n = 23) groups. The primary outcome was the incidence of postoperative complications. Secondary outcomes included chest tube duration, length of postoperative hospital stay, postoperative pain levels, and 30-day mortality.

RESULTS

The SRAMIE group did not experience conversions to thoracotomy or VAE. Compared with VAE, SRAMIE resulted in significantly shorter chest tube duration (p = 0.038), shorter postoperative hospital stays (p = 0.036), and lower peak postoperative pain (p = 0.003). No significant differences were observed among the groups regarding the total operative time, number of resected lymph nodes, or incidence of postoperative complications.

CONCLUSIONS

SRAMIE is a feasible approach offering advantages over VAE in recovery and postoperative pain. The comparable perioperative outcomes suggest that SRAMIE may be a viable alternative to conventional MIE, warranting further large-scale studies.

Evaluation of Gastric Conduit Perfusion Using Indocyanine Green Fluorescence During Radical Esophagectomy and Its Correlation With Anastomotic Leak: A Single-Center, Prospective Study

Background Anastomotic leak (AL) is a leading cause of morbidity after esophagectomy, with gastric conduit perfusion being a key predictor. The perfusion of the gastric conduit is often analyzed subjectively based on visual inspection, such as the presence of bright bleeding from the resection margin, pulsation of supplying arcade vessels, and tissue color. Indocyanine Green (ICG) fluorescence is a new tool that helps objectively assess the gastric conduit's perfusion. Aim To evaluate the role of ICG fluorescence in assessing gastric conduit perfusion and its correlation with AL. Methods This single-center prospective study from a tertiary hospital in South Asia included patients with esophageal cancer undergoing esophagectomy from December 2019 to December 2021. Gastric conduit perfusion was assessed using real-time ICG imaging with a near-infrared ICG camera (KARL STORZ® SE & Co. KG, Tuttlingen, Germany). It was done before and after trans-mediastinal pull-up and compared with visual perfusion assessment. AL was monitored for two weeks postoperatively. Results Sixteen patients (Male, 50%; mean age 53.7 years; squamous carcinoma, 81.2%; stage III-IVA, 50%; neoadjuvant treatment, 100%) undergoing minimally invasive esophagectomy (14 McKeown's, 2 Ivor Lewis) were included. Before and after the trans-mediastinal pull-up, visual assessment revealed "good" perfusion in 15 and 14 patients, respectively. However, according to the ICG-based evaluation, "good" perfusion was seen in just eight and two patients, respectively. Several conduits showing "good" visual perfusion exhibited "sluggish" perfusion on ICG fluorescence. One patient required conduit tip resection due to "poor" ICG perfusion despite a "good" visual assessment. Two patients (13.3%) developed AL, both of whom belonged to a group of five patients with a change in the ICG perfusion pattern of the gastric conduit from "good" to "sluggish" after its trans-mediastinal pull-up. A significant correlation (asymptotic sig. (2-tailed) P=0.022) was observed between real-time changes in the conduit's ICG perfusion speed between its abdominal and cervical positions and AL occurrence. Conclusion ICG fluorescence is a valuable tool for assessing gastric conduit perfusion during esophagectomy, identifying under-perfused conduits more accurately than visual evaluation. The time difference in perfusion speed before and after trans-mediastinal pull-up is critical, and we believe that assessing perfusion at both stages of the operation is crucial to identifying and addressing perfusion-related issues.

The Medical Basis for the Photoluminescence of Indocyanine Green

Indocyanine green (ICG), a near-infrared (NIR) fluorescent dye with unique photoluminescent properties, is a helpful tool in many medical applications. ICG produces fluorescence when excited by NIR light, enabling accurate tissue visualization and real-time imaging. This study investigates the fundamental processes behind ICG's photoluminescence as well as its present and possible applications in treatments and medical diagnostics. Fluorescence-guided surgery (FGS) has been transformed by ICG's capacity to visualize tumors, highlight blood flow, and facilitate lymphatic mapping, all of which have improved surgical accuracy and patient outcomes. Furthermore, the fluorescence of the dye is being studied for new therapeutic approaches, like photothermal therapy, in which NIR light can activate ICG to target and destroy cancer cells. We go over the benefits and drawbacks of ICG's photoluminescent qualities in therapeutic contexts, as well as current studies that focus on improving its effectiveness, security, and adaptability. More precise disease detection, real-time monitoring, and tailored therapy options across a variety of medical specialties are made possible by the ongoing advancement of ICG-based imaging methods and therapies. In the main part of our work, we strive to take into account the latest reports; therefore, we used clinical articles going back to 2020. However, for the sake of the theoretical part, the oldest article used by us is from 1995.

Indocyanine green fluorescent imaging (ICG-FI) in esophagectomy: single-center experience

<b>Introduction:</b> Gold standard treatment for locally advanced esophageal cancer is subtotal resection of the esophagus with resection of regional lymph nodes. Despite being performed in experienced and specialized centers, this procedure is associated with a high rate of complications. Complications such as anastomotic fistula and leakage can be life-threatening, primarily resulting from inadequate blood circulation in the anastomosis area. <br><br><b>Aim:</b> The aim of the study is to present the results of intraoperative indocyanine green (ICG) application in order to verify the adequate perfusion in esophagogastric anastomosis. <br><br><b>Materials and methods:</b> This is a single-center prospective analysis of 32 patients who underwent subtotal esophagectomy with regional lymph node resection for esophageal carcinoma. In all cases, intraoperative perfusion assessment using ICG fluorescence imaging (ICG-FI) was performed. Patient characteristics, comorbidities, and postoperative outcomes were analyzed, with treatment effects monitored for up to 1 year postoperatively. <br><br><b>Results:</b> Six patients required gastric conduit reduction due to poor blood perfusion visualized by intraoperative ICG-FI. Anastomotic leakage occurred in two cases, which were managed endoscopically with endo-vac therapy and esophageal stent placement. The remaining patients did not require additional surgical interventions during the postoperative course. <br><br><b>Conclusions:</b> The use of ICG dye in esophageal surgery appears to be a beneficial tool for objective assessment of perfusion that may be a valuable prediction factor in the postoperative course.

Successful Right Upper Lung Segmentectomy after Esophagectomy: Utilization of 4K 3-Dimensional Endoscopy and Near-Infrared Fluorescence in High-Risk Surgery

INTRODUCTION

Lung resection after open esophagectomy poses significant technical challenges, particularly when the reconstructed gastrointestinal tract is on the same side as the lung lesion. The advent of 4K 3-dimensional (3D) endoscopic systems with near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) has improved the precision of thoracic surgeries. We present a case of successful right upper lung segmentectomy for primary lung cancer after open esophagectomy, utilizing a 4K 3D endoscopic system and NIR imaging.

CASE PRESENTATION

An 85-year-old female with a history of open esophagectomy for esophageal cancer 19 years earlier and comorbidities, including aplastic anemia and diabetes mellitus, was referred for the evaluation of a growing lesion in the right upper lung. Computed tomography (CT) revealed a 43-mm tumor and the gastric tube, reconstructed during the prior esophagectomy, located in the right thoracic cavity. A CT-guided biopsy confirmed lung adenocarcinoma (cT2bN0M0, Stage IIA). Surgical challenges included severe adhesions from the previous thoracotomy and thrombocytopenia (platelet count: 20000) due to aplastic anemia. A thoracoscopic segmentectomy of the anterior segment of the right upper lobe was performed using a 4K 3D endoscopic system (TIPCAM1 Rubina; Karl Storz, Tuttlingen, Germany). Adhesions were meticulously dissected, and intraoperative platelet transfusions were administered. NIR imaging with ICG identified the intersegmental plane and confirmed blood flow to the gastric tube, preventing ischemic complications. The lung segmentectomy was completed using staplers, preserving the right gastroepiploic artery. Histopathology revealed acinar adenocarcinoma (pT3N0M0, Stage IIB). The patient resumed oral intake on postoperative Day 1 and was discharged on Day 13 without complications. No recurrence was noted during the follow-up.

CONCLUSIONS

This case demonstrates the effective use of 4K 3D endoscopic systems and NIR imaging with ICG in complex lung resections following open esophagectomy. These technologies facilitate precise dissection and blood flow assessment, which are crucial for preserving reconstructed structures and enhancing surgical safety.

The totally mechanical Collard technique for cervical esophagogastric anastomosis reduces anastomotic stricture compared with triangular anastomosis in minimally invasive esophagectomy with gastric conduit reconstruction through the retrosternal route: a propensity score-matched study

BACKGROUND

Cervical esophagogastric anastomosis is conventionally performed using the McKeown esophagectomy. However, an optimal anastomotic technique has not yet been established. This study aimed to compare the clinical outcomes of triangular anastomosis (TA) and totally mechanical Collard anastomosis (TMCA) for cervical esophagogastric anastomosis during minimally invasive esophagectomy with gastric conduit reconstruction through the retrosternal route.

METHODS

In this matched- cohort study, 117 patients who underwent minimally invasive esophagectomy between 2019 and 2024 were divided into TA and TMCA groups. The TA technique was performed between September 2019 and December 2021, and the TMCA technique was performed between January 2022 and January 2024. We then compared the surgical outcomes and postoperative complications (pneumonia, recurrent laryngeal nerve palsy, anastomotic leakage, and stricture) between the two groups.

RESULTS

Propensity score matching revealed that 40 patients were included in both the TA and TMCA groups. The rates of pneumonia, recurrent laryngeal nerve palsy, and anastomotic leakage were not significantly different between the two groups. However, the rate of anastomotic stricture was lower in the TMCA than in the TA group (2.5% vs. 27.5%, respectively, P = 0.003).

CONCLUSIONS

Compared with the TA technique, the TMCA technique reduced the rate of anastomotic stricture when performing cervical esophagogastric anastomosis during minimally invasive esophagectomy with gastric conduit reconstruction through the retrosternal route.

Indocyanine green and near-infrared fluorescence-guided surgery for gastric cancer: a narrative review

In recent years, indocyanine green (ICG) and near-infrared (NIR) fluorescence-guided surgery has become a versatile and well-researched tool for gastric cancer treatment. Our narrative review aims to explore the applications, benefits, and challenges that are associated with this technique. Initially used to detect sentinel lymph nodes in early gastric cancer, its scope has broadened to include several clinical applications. Its most notable advantages are the ability to guide standard lymphadenectomy, intraoperatively localize tumors and define tumor margins. Despite these advantages, there are still ongoing discussions regarding its accuracy, lack of standardized administration, and oncologic safety in sentinel node navigation surgery. The limited tumor specificity of ICG has been especially put into question, hindering its ability to accurately differentiate between malignant and healthy tissue. With ongoing innovations and its integration into newer endoscopic and robotic systems, ICG-NIR fluorescence imaging shows promise in becoming a standard tool in the surgical treatment of gastric cancer.

Predictive factors for refractory anastomotic stricture after cervical triangular anastomosis with gastric conduit reconstruction through the posterior mediastinum in minimally invasive esophagectomy

BACKGROUND

After esophagectomy, anastomotic strictures disturb food passage and increase the incidence of aspiration pneumonia. Multiple endoscopic balloon dilatations are required for stricture treatment. Therefore, long-term quality of life and nutritional status may be adversely affected. This study aimed to identify risk factors for strictures after cervical triangular anastomosis using a gastric conduit among patients who underwent minimally invasive esophagectomy (MIE).

METHODS

A total of 188 patients who underwent MIE for esophageal cancer between 2010 and 2020 at Kobe University Hospital were retrospectively examined. The incidence of strictures, number of dilatations for stricture, and time to stricture diagnosis were evaluated. Next, the potential independent risk factor for refractory strictures requiring more than 5 endoscopic balloon dilatations was clarified.

RESULTS

The study included 188 patients who satisfied the inclusion criteria. Anastomotic strictures were observed in 44 patients (23%). Neoadjuvant chemotherapy was significantly more common in patients with stricture than in patients without stricture (75% vs 58%, respectively; P = .041). The median number of endoscopic balloon dilatations was 5 (IQR, 1-31). Of note, 30 patients (68%) underwent their first dilatation within 3 months after MIE. In univariate and multivariate analyses, < 69 days from surgery to first endoscopic balloon dilatation was an independent risk factor for stricture requiring more than 5 endoscopic balloon dilatations after cervical triangular anastomosis in MIE (hazard ratio, 9.483; 95% CI, 2.220-54.274; P = .002).

CONCLUSION

Early postoperative anastomotic stricture might become refractory, and an appropriate treatment plan should be developed.

Clinical implementation of minimally invasive esophagectomy

BACKGROUND

Minimally invasive surgery is becoming the method of choice for the resection of esophageal cancer worldwide.

METHODS

Retrospective analysis of prospectively collected clinical data in a tertiary care center with a detailed description of the course of the program.

RESULTS

A total of 136 transthoracic esophageal resections were performed between 2010 and 2023. The study group included 116 operations, 69 of which were fully minimally invasive and 47 hybrid. 80.0% of the study group underwent surgery using a multimodality approach. The median operation time was 431 min (± 103). The R0 resection rate was 100%. Forty-two patients (36.2%) had no postoperative complications. The postoperative Clavien-Dindo > IIIb morbidity was 27%. The postoperative 90-d mortality rate was 1.7%. The average number of lymph nodes removed in the last quarter of cancer patients was 31. The anastomotic insufficiency rate for reoperation was 4% (Ivor-Lewis 4.2%, McKeown 5%).

CONCLUSIONS

With extensive expertise in high-end minimally invasive abdominal and thoracic surgery, implementation of a minimally invasive esophageal resection program with a clinical and oncologic outcome within generally accepted limits is feasible.

Gastric conduit reconstruction after esophagectomy

A high risk of complications still accompanies gastric conduit reconstruction after esophagectomy. In this narrative review, we summarize the technological progress and the problems of gastric conduit reconstruction after esophagectomy. Several types of gastric conduits exist, including the whole stomach and the narrow gastric tube. The clinical outcomes are similar between the two types of conduits. Sufficient blood supply to the conduit is mandatory for a successful esophageal reconstruction. Recently, due to the availability of equipment and its convenience, indocyanine green angiography has been rapidly spreading. When the blood perfusion of the planning anastomotic site is insufficient, several techniques, such as the Kocher maneuver, pedunculated gastric tube with duodenal transection, and additional microvascular anastomosis, exist to decrease the risk of anastomotic failure. There are two different anastomotic sites, cervical and thoracic, and mainly two reconstructive routes, retrosternal and posterior mediastinal routes. Meta-analyses showed no significant difference in outcomes between the anastomotic sites as well as the reconstructive routes. Anastomotic techniques include hand-sewn, circular, and linear stapling. Anastomoses using linear stapling is advantageous in decreasing anastomosis-related complications. Arteriosclerosis and poorly controlled diabetes are the risk factors for anastomotic leakage, while a narrow upper mediastinal space and a damaged stomach predict leakage. Although standardization among the institutional team members is essential to decrease anastomotic complications, surgeons should learn several technical options for predictable or unpredictable intraoperative situations.

Blood flow assessment of gastric tube with indocyanine green fluorescence angiography and postoperative endoscopy during esophagectomy: indocyanine green enhancement time indicated congestion

BACKGROUND

During esophagectomy, evaluation of blood supply to the gastric tube is critically important to estimate and avoid anastomotic complications. This retrospective study investigated the relationship between indocyanine green (ICG) fluorescence angiography during esophagectomy and postoperative endoscopy findings, especially mucosal color change.

METHODS

This study retrospectively collected data from 86 patients who underwent subtotal esophagectomy and reconstruction using a gastric tube for esophageal cancer at the Tokyo Medical and Dental University between 2017 and 2020. The flow speed of ICG fluorescence in the gastric tube was evaluated during the operation. Additionally, the main root of ICG enhancement and pattern of ICG distribution in the gastric tube were evaluated. On postoperative day 1 (POD1), the change in the mucosal color to white, thought to reflect ischemia, or black, thought to reflect congestion of the proximal gastric tube, was evaluated. The correlations between these factors, clinical parameters, and surgical outcomes were evaluated. Univariate and multivariate analyses used logistic regression to identify the risk factors affecting mucosal color change.

RESULTS

Multivariate analyses revealed that the only independent significant predictor of mucosal congestion on POD1 was the ICG enhancement time of the right gastric tube tip (odds ratio, 14.49; 95% confidential interval, 2.41-87.24; P = 0.004).

CONCLUSIONS

This study indicated that the ICG enhancement time is related to venous malperfusion and congestion rather than arterial malperfusion and ischemia.

Evaluation of the gastric conduit perfusion using indocyanine green in thoracoscopic esophagectomy for esophageal cancer

Objective

Indocyanine green has been used in the assessment of the gastric conduit perfusion in thoracoscopic esophagectomy to prevent malperfusion-associated anastomotic leak. This study aims to evaluate the initial results of investigating the gastric conduit perfusion with indocyanine green in the surgical treatment of esophageal cancer.

Patients and methods

This cross-sectional descriptive study was carried out on 54 esophageal cancer patients undergoing thoracoscopic esophagectomy and gastric conduit reconstruction. The blood flow in the gastric conduit was observed using an infrared camera and indocyanine green after completion of the conduit and after tunneling the conduit through the mediastinum to the neck.

Results

The gastric conduit width and length were 5.2 ± 0.3 cm, and 31.5 ± 1.6 cm, respectively. The length of the gastric conduit from the junction between the right and left gastroepiploic to the point where the distal end of the gastric conduit still has a vascular pulse was 11.9 ± 4.3 cm. Seventeen patients (31.5%) had poor blood supply at the distal end of the gastric conduit, with indocyanine green appearance time ⩾ 60 s, in whom anastomotic leaks occurred in five patients (9.3%). The lack of connection between the right and left gastroepiploic vessels was associated with poor blood supply of the distal gastric conduit (p = 0.04). Multivariable logistic regression analysis showed association between the time of indocyanine green appearance at the distal gastric conduit and the risk of anastomotic leak (OR = 1.99, 95% CI = 1.10-3.60, p = 0.02).

Conclusion

Investigation of gastric conduit perfusion using indocyanine green in gastric conduit reconstruction detected 31.5% of patients with poor blood supply at the distal end of the conduit, in whom 9.3% had anastomotic leak. The longer indocyanine green appearance time in the distal gastric conduit (segment BC), was associated with the higher rate of the anastomotic leak.

Evaluation of the blood flow in reconstructed gastric tube and its relation to anastomosis leakage

OBJECTIVES

Anastomotic leakage in esophageal cancer surgery may be reduced by evaluating the blood flow to the reconstructed organ, but quantitative evaluation of arterial and venous blood flow is difficult. This study aimed to quantitatively assess blood flow using a new technique, as well as determine the relationship between the blood flow in the gastric tube and anastomotic leakage using near-infrared spectroscopy.

METHODS

This single-center, observational study included 50 patients aged 51-82 years who underwent radical esophagectomy with gastric tube reconstruction for esophageal cancer between June 2022 and January 2023. Regional tissue oxygen saturation was measured at the antrum (point X), the anastomotic point (point Z), and the midpoint between points X and Z (point Y) before and after gastric tube formation. These three points of oxygen saturation were investigated in relation to anastomotic leakage.

RESULTS

When comparing the presence of leakage to its absence, regional tissue oxygen saturation at points X and Z after gastric tube formation was significantly lower (X: p = 0.03, Z: p = 0.02), with the decreasing rate significantly higher at point Z (p = 0.01). There was no significant difference in the decreasing rate of regional tissue oxygen saturation between points X and Y (X: p = 0.052, Y: p = 0.83).

CONCLUSION

Regional tissue oxygen saturation levels may be useful for measuring blood flow and could be a predictor of anastomotic leakage.

Real-time quantification of laser speckle contrast imaging during intestinal laparoscopic surgery: successful demonstration in a porcine intestinal ischemia model

BACKGROUND

Anastomotic leakage (AL) is a dreaded complication following colorectal cancer surgery, impacting patient outcome and leads to increasing healthcare consumption as well as economic burden. Bowel perfusion is a significant modifiable factor for anastomotic healing and thus crucial for reducing AL.

AIMS

The study aimed to calculate a cut-off value for quantified laser speckle perfusion units (LSPUs) in order to differentiate between ischemic and well-perfused tissue and to assess inter-observer reliability.

METHODS

LSCI was performed using a porcine ischemic small bowel loop model with the PerfusiX-Imaging® system. An ischemic area, a well-perfused area, and watershed areas, were selected based on the LSCI colormap. Subsequently, local capillary lactate (LCL) levels were measured. A logarithmic curve estimation tested the correlation between LSPU and LCL levels. A cut-off value for LSPU and lactate was calculated, based on anatomically ischemic and well-perfused tissue. Inter-observer variability analysis was performed with 10 observers.

RESULTS

Directly after ligation of the mesenteric arteries, differences in LSPU values between ischemic and well-perfused tissue were significant (p < 0.001) and increased significantly throughout all following measurements. LCL levels were significantly different (p < 0.001) at both 60 and 120 min. Logarithmic curve estimation showed an R2 value of 0.56 between LSPU and LCL values. A LSPU cut-off value was determined at 69, with a sensitivity of 0.94 and specificity of 0.87. A LCL cut-off value of 3.8 mmol/L was found, with a sensitivity and specificity of 0.97 and 1.0, respectively. There was no difference in assessment between experienced and unexperienced observers. Cohen's Kappa values were moderate to good (0.52-0.66).

CONCLUSION

Real-time quantification of LSPUs may be a feasible intraoperative method to assess tissue perfusion and a cut-off value could be determined with high sensitivity and specificity. Inter-observer variability was moderate to good, irrespective of prior experience with the technique.

Immediate breast reconstruction with laparoscopically harvested omental flap: A retrospective analysis with a maximum 12-year follow-up

PURPOSE

To evaluate the clinical efficacy of immediate breast reconstruction with free or pedicled laparoscopically harvested omental flaps (LHOFs).

METHODS

Between March 2011 and 2021, 82 patients who underwent immediate breast reconstruction with free or pediculated omental flaps were enrolled. Breast total or partial mastectomy, laparoscopic greater omentum harvest, and breast reconstruction were carried out in an orderly manner. Postoperative operative results, cosmetic outcomes, and complications were investigated.

RESULTS

Seventeen cases of free LHOF and 65 cases of pedicled LHOF were performed. Cosmetic results were mostly satisfactory (61% excellent, 35% good), with a soft breast that was natural in appearance. Satisfaction investigation showed that 96.2% of patients were satisfied with the reconstructed breast. Uneventful follow-up showed no abdominal complications at the donor site, and the surface skin displayed no swelling. No major complications were found, except for three cases of necrosis. One patient developed slight hematoma. Two patients were found to have local recurrence, and one had distant metastasis. Twenty-four patients accepted radiotherapy, but no size reduction was noted after radiotherapy. We followed the patients to determine their survival status. All patients were alive, except for 1 in the free LHOF group who died 31.2 months after surgery.

CONCLUSION

Immediate breast reconstruction with LHOF provides a soft reconstructed breast with relatively little donor-site deformity and is useful for breast tumor-specific immediate reconstruction.

Current status of indocyanine green fluorescent angiography in assessing perfusion of gastric conduit and oesophago-gastric anastomosis

Anastomotic leak (AL) remains a significant complication after esophagectomy. Indocyanine green fluorescent angiography (ICG-FA) is a promising and safe technique for assessing gastric conduit (GC) perfusion intraoperatively. It provides detailed visualization of tissue perfusion and has demonstrated usefulness in oesophageal surgery. GC perfusion analysis by ICG-FA is crucial in constructing the conduit and selecting the anastomotic site and enables surgeons to make necessary adjustments during surgery to potentially reduce ALs. However, anastomotic integrity involves multiple factors, and ICG-FA must be combined with optimization of patient and procedural factors to decrease AL rates. This review summarizes ICG-FA's current applications in assessing esophago-gastric anastomosis perfusion, including qualitative and quantitative analysis and different imaging systems. It also explores how fluorescent imaging could decrease ALs and aid clinicians in utilizing ICG-FA to improve esophagectomy outcomes.

Minimally invasive surgery for gastro-oesophageal junction adenocarcinoma: Current evidence and future perspectives

Minimally invasive surgery is increasingly indicated in the management of malignant disease. Although oesophagectomy is a difficult operation, with a long learning curve, there is actually a shift towards the laparoscopic/thoracoscopic/ robotic approach, due to the advantages of visualization, surgeon comfort (robotic surgery) and the possibility of the whole team to see the operation as well as and the operating surgeon. Although currently there are still many controversial topics, about the surgical treatment of patients with gastro-oesophageal junction (GOJ) adenocarcinoma, such as the type of open or minimally invasive surgical approach, the type of oesophago-gastric resection, the type of lymph node dissection and others, the minimally invasive approach has proven to be a way to reduce postoperative complications of resection, especially by decreasing pulmonary complications. The implementation of new technologies allowed the widening of the range of indications for this type of surgical approach. The short-term and long-term results, as well as the benefits for the patient - reduced surgical trauma, quick and easy recovery - offer this type of surgical treatment the premises for future development. This article reviews the updates and perspectives on the minimally invasive approach for GOJ adenocarcinoma.

Near-infrared fluorescence imaging with indocyanine green to assess the blood supply of the reconstructed gastric conduit to reduce anastomotic leakage after esophagectomy: a literature review

The blood supply of the right gastroepiploic artery after esophagectomy with gastric tube reconstruction is essential for avoiding anastomotic leakage. Near-infrared fluorescence (NIRF) imaging with indocyanine green is widely used to assess the blood supply because it can visualize it in real-time during navigation surgery. However, there is no established protocol for this modality. One reason for this lack of protocol is that NIRF provides subjective information. This study aimed to evaluate NIRF quantification. We conducted a literature review of risk factors for anastomotic leakage after esophagectomy, NIRF procedures, NIRF quantification, and new methods to compensate for NIRF limitations. Major methods for the quantification of NIRF include measuring the blood flow speed, visualization time, and fluorescence intensity. The cutoff value for the blood flow speed is 2.07 cm/s, and that for the visualization time is 30-90 s. Although the time-intensity curve provided patterns of change in the blood flow, it did not show an association with anastomotic leakage. However, to compensate for the limitations of NIRF, new devices have been reported that can assess tissue oxygenation perfusion, organ hemoglobin concentration, and microcirculation.

Predictive impact of the thoracic inlet space on ICG fluorescence blood flow speed in the gastric conduit wall and anastomotic leakage after esophagectomy

PURPOSE

The thoracic inlet space might influence the blood vessel perfusion in the gastric conduit. The purpose of this study was to clarify the impacts of the thoracic inlet space on blood vessel perfusion in the gastric conduit and anastomotic leakage after esophagectomy.

METHODS

One hundred and forty-two esophageal cancer patients underwent esophagectomy followed by gastric conduit reconstruction via the retrosternal route. The blood flow speed in the gastric conduit was measured using indocyanine green fluorescence before and after reconstruction. Parameters at the thoracic inlet space were measured using CT. We then investigated the correlation between these two parameters and whether they could predict anastomotic leakage after esophagectomy.

RESULTS

Blood flow speed in the gastric conduit was slower after reconstruction than before reconstruction (P < 0.001). The incidence of anastomotic leakage (n = 23) was higher among patients with a delayed blood flow speed before reconstruction (n = 27) than among those with a non-delayed blood flow speed before reconstruction (n = 115) (P < 0.001). Among the patients with a non-delayed blood flow speed before reconstruction, the thoracic inlet area (TIA, sternum-tracheal distance × clavicle head distance) was positively correlated with the blood flow speed after reconstruction (P = 0.023) and was identified as an independent predictor of anastomotic leakage (P < 0.001).

CONCLUSION

A narrow TIA was associated with a delayed blood flow speed in the gastric conduit after reconstruction and was capable of predicting anastomotic leakage in the patients with a non-delayed blood flow speed before reconstruction.

Intraoperative fluorescence imaging in esophagectomy and its application to the robotic platform: a narrative review

Background and Objective

Robotic-assisted esophagectomy is an approach to minimally invasive esophagectomy (MIE) that has demonstrated equivalent or improved outcomes relative to open and other minimally invasive techniques. The robotic approach also allows unique opportunities to improve complications following esophagectomy through use of enhanced visualization tools, including intraoperative fluorescence imaging. In this review, we summarize the specific uses of intraoperative fluorescence imaging as an adjunct tool during esophagectomy and discuss its application to the robotic platform.

Methods

A literature search was conducted via PubMed in February 2022 with the following keywords: esophagectomy, esophageal cancer, infrared, near-infrared (NIR) and fluorescence. Peer-reviewed academic journal articles published in English between 2000 and 2021 were included.

Key Content and Findings

There is a growing body of literature evaluating the use of intraoperative fluorescence imaging in robotic-assisted esophagectomy. This includes assessment of gastric conduit perfusion, including feasibility, creation of the gastroesophageal anastomosis, and qualification of perfusion, along with lymphatic mapping and identification of critical anatomy. These tools are uniquely leveraged using the robotic platform to standardize and quantify key technical aspects of the operation.

Conclusions

Intraoperative fluorescence imaging provides the opportunity to assess perfusion and identify anatomy for more precise and patient-specific dissection and reconstruction. Among all the operative techniques for esophagectomy, robotic-assisted esophagectomy is uniquely suited to utilize these imaging modalities to optimize outcomes and minimize risk associated with esophagectomy.

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.

Near-Infrared Fluorescence Image-Guided Surgery in Esophageal and Gastric Cancer Operations

BACKGROUND

Near-infrared fluorescence image-guided surgery helps surgeons to see beyond the classical eye vision. Over the last few years, we have witnessed a revolution which has begun in the field of image-guided surgery.

PURPOSE, AND RESEARCH DESIGN

Fluorescence technology using indocyanine green (ICG) has shown promising results in many organs, and in this review article, we wanted to discuss the 6 main domains where fluorescence image-guided surgery is currently used for esophageal and gastric cancer surgery.

STUDY SAMPLE AND DATA COLLECTION

Visualization of lymphatic vessels, tumor localization, fluorescence angiography for anastomotic evaluation, thoracic duct visualization, tracheal blood flow analysis, and sentinel node biopsy are discussed.

CONCLUSIONS

It seems that this technology has already found its place in surgery. However, new possibilities and research avenues in this area will probably make it even more important in the near future.

Qualitative features of esophageal fluorescence angiography and anastomotic outcomes in children

BACKGROUND

Indocyanine green (ICG) is commonly used to assess perfusion, but quality defining features are lacking. We sought to establish qualitative features of esophageal ICG perfusion assessments, and develop an esophageal anastomotic scorecard to risk-stratify anastomotic outcomes.

METHODS

Single institution, retrospective analysis of children with an intraoperative ICG perfusion assessment of an esophageal anastomosis. Qualitative perfusion features were defined and a perfusion score developed. Associations between perfusion and clinical features with poor anastomotic outcomes (PAO, leak or refractory stricture) were evaluated with logistic and time-to-event analyses. Combining significant features, we developed and tested an esophageal anastomotic scorecard to stratify PAO risk.

RESULTS

From 2019 to 2021, 53 children (median age 7.4 months) underwent 55 esophageal anastomoses. Median (IQR) follow-up was 14 (10-19.9) months; mean (SD) perfusion score was 13.2 (3.4). Fifteen (27.3%) anastomoses experienced a PAO and had significantly lower mean perfusion scores (11.3 (3.3) vs 14.0 (3.2), p = 0.007). Unique ICG perfusion features, severe tension, and primary or rescue traction-induced esophageal lengthening [Foker] procedures were significantly associated with PAO on both logistic and Cox regression. The scorecard (range 0-7) included any Foker (+2), severe tension (+1), no arborization on either segment (+1), suture line hypoperfusion >twice expected width (+2), and segmental or global areas of hypoperfusion (+1). A scorecard cut-off >3 yielded a sensitivity of 73% and specificity of 93% (AUC 0.878 [95%CI 0.777 to 0.978]) in identifying a PAO.

CONCLUSIONS

A scoring system comprised of qualitative ICG perfusion features, tissue quality, and anastomotic tension can help risk-stratify esophageal anastomotic outcomes accurately.

LEVELS OF EVIDENCE

Diagnostic - II.

Application of Indocyanine Green Enhanced Fluorescence in Esophageal Surgery: A Mini Review

Despite recent technological innovations and the development of minimally invasive surgery, esophagectomy remains an operation burdened with severe postoperative complications. Fluorescence imaging, particularly using indocyanine green (ICG), offers the ability to address a number of issues faced during esophagectomy. The three main indications for the intraoperative use of ICG during esophagectomy are visualization of conduit vascular supply, allow identification of sentinel nodes and visualization of the thoracic duct. The purpose of this mini review is to present an overview of current practice in fluorescence imaging utilizing ICG during esophagectomy, as well as to demonstrate how this technology can guide lymphadenectomy and reduce surgical morbidity such as anastomotic leaking and chylothorax.

The Use of Indocyanine Green (ICG) and Near-Infrared (NIR) Fluorescence-Guided Imaging in Gastric Cancer Surgery: A Narrative Review

Near-infrared fluorescence imaging with indocyanine green is an emerging technology gaining clinical relevance in the field of oncosurgery. In recent decades, it has also been applied in gastric cancer surgery, spreading among surgeons thanks to the diffusion of minimally invasive approaches and the related development of new optic tools. Its most relevant uses in gastric cancer surgery are sentinel node navigation surgery, lymph node mapping during lymphadenectomy, assessment of vascular anatomy, and assessment of anastomotic perfusion. There is still debate regarding the most effective application, but with relatively no collateral effects and without compromising the operative time, indocyanine green fluorescence imaging carved out a role for itself in gastric resections. This review aims to summarize the current indications and evidence for the use of this tool, including the relevant practical details such as dosages and times of administration.

Indocyanine green fluorescence imaging for evaluating blood flow in the reconstructed conduit after esophageal cancer surgery

We investigated the effectiveness of indocyanine green (ICG) fluorescence blood flow imaging of the gastric conduit to evaluate anastomotic leakage after esophagectomy. We identified 19 articles using the PRISMA standard for systematic reviews. The more recent studies reported attempts at objective quantification of ICG fluorescence imaging, rather than qualitative assessment. Anastomotic leakage after esophagectomy occurred in 0-33% of the patients who underwent ICG fluorescence imaging. According to the six studies that compared the incidence of anastomotic leakage in the ICG group and the control group, it ranged from 0 to 18.3% in the ICG group and from 0 to 25.2% in the control group, respectively. Overall, the incidence of anastomotic leakage in the ICG group (8.4%) was lower than that in the control group (18.5%). Although the incidence of anastomotic leakage was as high as 43.1% in patients who did not undergo any intraoperative intervention for poor blood flow, it was only 24% in patients who underwent intraoperative intervention. This systematic review revealed that ICG fluorescence imaging may be a crucial adjunctive tool for reducing anastomotic leakage after esophagectomy, suggesting that it should be performed during esophageal reconstruction.

Clinical utility of near-infrared perfusion assessment of the gastric tube during Ivor Lewis esophagectomy

BACKGROUND

Anastomotic leakage (AL) after Ivor Lewis esophagectomy with intrathoracic anastomosis carries a significant morbidity. Adequate perfusion of the gastric tube (GT) is an important predictor of anastomotic integrity. Recently, near infrared fluorescent (NIRF) imaging using indocyanine green (ICG) was introduced in clinical practice to evaluate tissue perfusion. We evaluated the feasibility and efficacy of GT indocyanine green angiography (ICGA) after Ivor Lewis esophagectomy.

METHODS

This retrospective analysis used data from a prospectively kept database of consecutive patients who underwent Ivor Lewis (IL) esophagectomy with GT construction for cancer between January 2016 and December 2020. Relevant outcomes were feasibility, ICGA complications and the impact of ICGA on AL.

RESULTS

266 consecutive IL patients were identified who matched the inclusion criteria. The 115 patients operated with perioperative ICGA were compared to a control group in whom surgery was performed according to the standard of care. ICGA perfusion assessment was feasible and safe in all 115 procedures and suggested a poorly perfused tip in 56/115 (48.7%) cases, for which additional resection was performed. The overall AL rate was 16% (43/266), with 12% (33/266) needing an endoscopic our surgical intervention and 6% (17/266) needing ICU support. In univariable and multivariable analyses, ICGA was not correlated with the risk of AL (ICGA:14.8% vs non-ICGA:17.2%, p = 0.62). However, poor ICGA perfusion of the GT predicted a higher AL rate, despite additional resection of the tip (ICGA poorly perfused: 19.6% vs ICG well perfused: 10.2%, p = 0.19).

CONCLUSIONS

ICGA is safe and feasible, but did not result in a reduction of AL. The interpretation and necessary action in case of perioperative presence of ischemia on ICGA have yet to be determined. Prospective randomized trials are warranted to analyze its benefit on AL in esophageal surgery. Trial registration Ethical approval for a prospective esophageal surgery database was granted by the Ethical committee of the Ghent University Hospital. Belgian registration number: B670201111232. Ethical approval for this retrospective data analysis was granted by our institutional EC. Registration number: BC-09216.

Quantitative Fluorescence Imaging of Perfusion—An Algorithm to Predict Anastomotic Leakage

This study tests fluorescence imaging-derived quantitative parameters for perfusion evaluation of the gastric tube during surgery and correlates these parameters with patient outcomes in terms of anastomotic leakage. Poor fundus perfusion is seen as a major factor for the development of anastomotic leakage and strictures. Fluorescence perfusion imaging may reduce the incidence of complications. Parameters for the quantification of the fluorescence signal are still lacking. Quantitative parameters in terms of maximal intensity, mean slope and influx timepoint were tested for significant differences between four perfusion areas of the gastric tube in 22 patients with a repeated ANOVA test. These parameters were compared with patient outcomes. Maximal intensity, mean slope and influx timepoint were significantly different between the base of the gastric tube and the fundus (p < 0.0001). Patients who developed anastomotic leakage showed a mean slope of almost 0 in Location 4. The distance of the demarcation of ICG to the fundus was significantly higher in the three patients who developed anastomotic leakage (p < 0.0001). This study presents quantitative intra-operative perfusion imaging with fluorescence. Quantification of the fluorescence signal allows for early risk stratification of necrosis.

Distal partial gastrectomy for gastric tube cancer with intraoperative blood flow evaluation using indocyanine green fluorescence

With recent advances in the treatment of esophageal cancer and long-term survival after esophagectomy, the number of gastric tube cancer (GTC) has been increasing. Total gastric tube resection with lymph node dissection is considered to be a radical treatment, but it causes high post-operative morbidity and mortality. We report an elderly patient with co-morbidities who developed pyloric obstruction due to GTC after esophagectomy with retrosternal reconstruction. The patient was treated using distal partial gastric tube resection (PGTR) and Roux-en-Y reconstruction with preservation of the right gastroepiploic artery and right gastric artery. Intraoperative blood flow visualization using indocyanine green (ICG) fluorescence demonstrated an irregular demarcation line at the distal side of the preserved gastric tube, indicating a safe surgical margin to completely remove the ischemic area. PGTR with intraoperative ICG evaluation of blood supply in the preserved gastric tube is a safe and less-invasive surgical option in patients with poor physiological condition.

Assessing the development status of intraoperative fluorescence imaging for perfusion assessments, using the IDEAL framework

Objectives

Intraoperative fluorescence imaging is currently used in a variety of surgical fields for four main purposes: assessing tissue perfusion; identifying/localizing cancer; mapping lymphatic systems; and visualizing anatomy. To establish evidence-based guidance for research and practice, understanding the state of research on fluorescence imaging in different surgical fields is needed. We evaluated the evidence on fluorescence imaging for perfusion assessments using the Idea, Development, Exploration, Assessment, Long Term Study (IDEAL) framework, which was designed for describing the stages of innovation in surgery and other interventional procedures.

Design

Narrative literature review with analysis of IDEAL stage of each field of study.

Setting

All publications on intraoperative fluorescence imaging for perfusion assessments reported in PubMed through 2019 were identified for six surgical procedures: coronary artery bypass grafting (CABG), upper gastrointestinal (GI) surgery, colorectal surgery, solid organ transplantation, reconstructive surgery, and cerebral aneurysm surgery.

Main outcome measures

The IDEAL stage of research evidence was determined for each specialty field using a previously described approach.

Results

196 articles (15 003 cases) were selected for analysis. Current status of research evidence was determined to be IDEAL Stage 2a for upper GI and transplantation surgery, IDEAL 2b for CABG, colorectal and cerebral aneurysm surgery, and IDEAL Stage 3 for reconstructive surgery. Using the technique resulted in a high (up to 50%) rate of revisions among surgical procedures, but its efficacy improving postoperative outcomes has not yet been demonstrated by randomized controlled trials in any discipline. Only one possible adverse reaction to intravenous indocyanine green was reported.

Conclusions

Using fluorescence imaging intraoperatively to assess perfusion is feasible and appears useful for surgical decision making across a range of disciplines. Identifying the IDEAL stage of current research knowledge aids in planning further studies to establish the potential for patient benefit.

Indocyanine green enhanced near-infrared fluorescence imaging for perfusion assessment of colonic conduit for esophageal replacement: Utility of a novel technique

Esophagectomy, followed by esophageal replacement using gastric/colonic conduits, is a complex surgical procedure with significant perioperative morbidity. The most significant and potentially life-threatening complication associated with esophageal replacement is conduit ischaemia, resulting in anastomotic leak and conduit necrosis. Ensuring adequate perfusion of the conduit remains the key to preventing conduit ischaemia. Indocyanine green (ICG) enhanced near-infrared fluorescence imaging is a novel technique which has been used for assessing bowel perfusion. While numerous studies have focused on ICG fluorescence imaging for assessment of gastric conduit perfusion after esophagectomy, data regarding its use for colonic conduits is limited to case reports. ICG fluorescence imaging can help in resolving intraoperative issues by predicting the adequacy of colonic conduit perfusion, thereby preventing postoperative morbidity. To the best of our knowledge, this is the first report in Indian literature describing the utility of ICG fluorescence imaging for assessment of perfusion of colonic interposition.

Indocyanine green fluorescence imaging ensures perfusion of the remnant stomach during laparoscopic splenectomy in a patient after distal gastrectomy: A case report

Background

After distal gastrectomy, ischemic necrosis of the remnant stomach is a rare but serious complication. For distal pancreatectomy or splenectomy, ensuring adequate blood supply to the remnant stomach is important for patients with a history of distal gastrectomy. We report a case of successful splenectomy with indocyanine green (ICG) used to evaluate the blood supply to the remnant stomach in a patient after distal gastrectomy.

Case presentation

A 65-year-old woman who underwent distal gastrectomy for gastric cancer a year earlier had a splenic tumor that was increasing in size. We planned laparoscopic splenectomy because there was a possibility of a malignant splenic tumor. Intraoperative ICG fluorescence imaging confirmed perfusion of the remnant stomach. The patient was discharged on postoperative day 8 after an uncomplicated postoperative course.

Conclusion

ICG fluorescence imaging is useful for evaluating blood flow to the remnant stomach during laparoscopic splenectomy in patients after distal gastrectomy.

•

Ischemic necrosis of the remnant stomach is a serious complication for patients with a history of distal gastrectomy.

•

During laparoscopic surgery, the method for evaluating the blood supply to remnant stomach has not been established.

•

ICG fluorescence imaging is only way to visually evaluate the blood supply to organs during surgery.

•

Using ICG fluorescence imaging during laparoscopic splenectomy, ischemic necrosis of the remnant stomach can be prevented.

A Novel and Generic Workflow of Indocyanine Green Perfusion Assessment Integrating Standardization and Quantification Towards Clinical Implementation

OBJECTIVE

This study aims to generate a reproducible and generalizable Workflow model of ICG-angiography integrating Standardization and Quantification (WISQ) that can be applied uniformly within the surgical innovation realm independent of the user.

SUMMARY BACKGROUND DATA

Tissue perfusion based on indocyanine green (ICG)-angiography is a rapidly growing application in surgical innovation. Interpretation of have been subjective and error-prone due to the lack of a standardized and quantitative ICG-workflow and analytical methodology. There is a clinical need for a more generic, reproducible, and quantitative ICG perfusion model for objective assessment of tissue perfusion.

METHODS

In this multicenter, proof-of-concept study, we present a generic and reproducible ICG-workflow integrating standardization and quantification for perfusion assessment. To evaluate our model's clinical feasibility and reproducibility, we assessed the viability of parathyroid glands after performing thyroidectomy. Biochemical hypoparathyroidism was used as the postoperative endpoint and its correlation with ICG quantification intraoperatively. Parathyroid gland are an ideal model as parathyroid function post-surgery is only affected by perfusion.

RESULTS

We show that visual -subjective- interpretation of ICG-angiography by experienced surgeons on parathyroid perfusion cannot reliably predict organ function impairment postoperatively, emphasizing the importance of an ICG quantification model. WISQ was able to standardize and quantify ICG-angiography and provided a robust and reproducible perfusion curve analysis. A low ingress slope of the perfusion curve combined with a compromised egress slope was indicative for parathyroid organ dysfunction in 100% of the cases.

CONCLUSION

WISQ needs prospective validation in larger series and may eventually support clinical decision-making to predict and prevent postoperative organ function impairment in a large and varied surgical population.

Salvage Esophagectomy

Salvage esophagectomy is an option for patients with recurrent or persistent esophageal cancer after definitive chemoradiation therapy or those who undergo active surveillance after induction chemoradiation therapy. Salvage resection is associated with higher rates of morbidity compared with planned esophagectomy but offers patients with locally advanced disease a chance at improved long-term survival. Salvage resection should be preferentially performed in a multidisciplinary setting by high-volume and experienced surgeons. Technical considerations, such as prior radiation dosage, radiation field, and choice of conduit, should be taken into account.

The evaluation of the gastric tube blood flow by indocyanine green fluorescence angiography during esophagectomy: a multicenter prospective study

OBJECTIVE

We determined the anastomotic site during gastric tube reconstruction in esophagectomy according to the "90-to 60-s rule" using indocyanine green (ICG) fluorescence angiography. We evaluated its safety and efficacy in a prospective multicenter setting.

METHODS

We enrolled 129 patients who underwent subtotal esophagectomy for esophageal cancer. ICG fluorescence angiography was performed after making a wide gastric tube, and the time from the initial enhancement of the right gastroepiploic artery to the tip of the gastric tube was used as a parameter. Esophago-gastro anastomosis was made at the area that was enhanced within 90 s (preferably within 60 s). The enhancement time and the incidence of anastomotic leakage were compared.

RESULTS

In all cases, anastomosis was made at the site enhanced within 90 s. Anastomotic leakage was found in only 4 (3.1%) of 129 cases; specifically, it was detected in 3 (2.4%) of 126 cases whose anastomotic site was enhanced within 60 s and in 1 (33.3%) of 3 cases where the enhancement time exceeded 60 s (p = 0.09).

CONCLUSIONS

Determining the anastomotic site using the 90-to 60-s rule with ICG imaging in gastric tube reconstruction helps reduce the rate of anastomotic leakage.

Association between indocyanine green fluorescence blood flow speed in the gastric conduit wall and superior mesenteric artery calcification: predictive significance for anastomotic leakage after esophagectomy

BACKGROUND

Near-infrared fluorescence using indocyanine green (ICG) has been applied as a real-time navigation tool to observe blood flow in gastric conduit wall after esophagectomy. Atherosclerosis might impair the blood flow of the systemic organs. The aim of the study was to investigate the significances of ICG blood flow speed in the gastric conduit wall and atherosclerotic calcification for the prediction of anastomotic leakage after esophagectomy.

METHODS

The 109 esophageal cancer patients were prospectively enrolled. ICG fluorescence blood flow speed in the gastric conduit wall and abdominal aortic calcification index (ACI), celiac artery (CA) calcification, and superior mesenteric artery (SMA) calcification were determined. Then, the correlation between ICG fluorescence blood flow speed and anastomotic leakage as well as ACI, CA, and SMA calcification were evaluated.

RESULTS

Anastomotic leakage occurred in 15 patients. ACI ranged from 0 to 65. CA calcification and SMA calcification were present in 25 and 12 patients. Multivariate analysis demonstrated that ICG fluorescence blood flow speed in the gastric conduit wall of 2.07 cm/s or less (P < 0.001) and SMA calcification (P = 0.026) were the significant independent predictors of anastomotic leakage. Only SMA calcification was significantly associated with ICG fluorescence blood flow speed in the gastric conduit wall (P = 0.026).

CONCLUSIONS

This study demonstrated that ICG fluorescence blood flow speed in the gastric conduit wall can predict anastomotic leakage after esophagectomy and microvascular perfusion of capillary vessels of the gastric conduit might be impaired by systemic atherosclerosis.

The histopathological evaluation based on the indocyanine green fluorescence imaging of regional lymph node metastasis of splenic flexural colon cancer by near-infrared observation

PURPOSE

The purpose of this study was to investigate the relationship between the fluorescence on indocyanine green fluorescent imaging (ICG-FI) and the histopathological findings of regional lymph node (LN) metastasis of splenic flexural colon cancer.

METHODS

From July 2013 to December 2018, consecutive patients with splenic flexural colon cancer with a preoperative diagnosis of N0 who underwent laparoscopic surgery were enrolled. The distribution of cancer sites in metastatic LNs (completely/not completely occupied by metastatic foci) was evaluated with hematoxylin and eosin-stained preparations. We compared the relationship between the distribution of cancer site and fluorescence of paraffin block in metastatic LNs.

RESULTS

Seventy-two patients were enrolled, of whom 13 (18.1%) had metastatic LNs. A total of 25 metastatic LNs were evaluated. The median short axis of the occupied LNs was 4.5 mm, which was significantly larger than that of the non-occupied LNs (3.0 mm; p = 0.036). In the near-infrared observation of the paraffin block, the completely occupied LNs showed no fluorescence, regardless of the LN size, but 8 of 10 non-occupied LNs showed fluorescence (p < 0.001). Even the non-occupied LNs that showed fluorescence, the cancer site did not show fluorescence.

CONCLUSIONS

The occupied LNs showed no fluorescence, but 80% of the non-occupied LNs showed fluorescence. Even in non-occupied LNs that showed fluorescence, the cancer site did not show fluorescence. This demonstrated LN dissection should not be omitted, even if no fluorescence is noted on intraoperative ICG-FI.

Fluorescence-guided cancer surgery-A new paradigm

Fluorescence-guided surgery is an emerging and promising operative adjunct to assist the surgeon in various aspects of oncosurgery, ranging from assessing perfusion, identification, and characterization of tumors and peritoneal metastases, mapping of lymph nodes/leaks, and assistance for fluorescence-guided surgery (FGS). This study aims to provide an overview of principles, currently available dyes, platforms, and surgical applications and summarizes the available literature on the utility of FGS with a focus on abdomino-thoracic malignancies.

The ratio of gastric tube length to thorax length: a vital factor affecting leak after esophageal cervical anastomosis

Background

Esophagogastric anastomotic leak (AL) is a severe complication following esophageal resection. This study aims to explore preliminarily whether the ratio of the gastric conduit length to the thorax length can be regarded as a potential prognostic variable for AL, and if so, a cut-off value can be found to divide the patients into distinct risk groups.

Methods

We retrospectively reviewed the clinical data of 273 patients who underwent esophagectomy. The gastric conduit length, the thorax length, and other covariates were collected. Logistic regression was first conducted to probe the rationality of the ratio as a risk indicator of AL. Then the dichotomizing analysis was applied to find the optimal cut-off value.

Results

The incidence of AL was 12.5% (34/273). The coefficient of the ratio in the logistic regression equation was –7.901 with P<0.001, which indicated that the larger the ratio, the smaller the risk of AL. Further smoothed scatter plots revealed that a potential step function of the ratio of AL incidence exists, of which the steep part ranges from 1.74 to 1.90. Results of the accurate cut-off value search through a minimum P value approach give the optimal dichotomization point of 1.79.

Conclusions

The ratio of the gastric conduit length to the thorax length can reflect the tension in the anastomosis. The research proposes that surgeons can control the length of the gastric conduit during reconstruction to reduce the tension in the anastomosis and thus lead to a decrease in the incidence of AL.

Indocyanine Green (ICG) fluorescence angiography of gastric conduit after transhiatal thoracic esophagectomy with proximal gastrectomy for esophagogastric junction adenocarcinoma: A case report and initial experience at a tertiary government hospital in the Philippines

INTRODUCTION AND IMPORTANCE

We documented the initial experience in our institution where we used indocyanine green (ICG) fluorescence angiography as adjunct in the evaluation of the vascular supply of a reconstructed gastric conduit for esophageal replacement for esophagogastric junction (EGJ) cancer surgery.

CASE PRESENTATION

A 62-year-old patient consulted with a two-month history of melena and weight loss and unremarkable chest and abdominal physical examinations.

CLINICAL FINDINGS AND INVESTIGATIONS

Upper endoscopy and contrast-enhanced computed tomography scans of the chest and abdomen demonstrated an EGJ tumor with no nodal and distant metastases, which revealed adenocarcinoma on biopsy.

INTERVENTION AND OUTCOME

The patient underwent combined thoracoscopic-assisted and transhiatal thoracic esophagectomy with proximal gastrectomy. Esophageal reconstruction was done via a retrosternal gastric pull-up. The perfusion and viability of the gastric conduit were confirmed as per usual methods of inspection and palpation. ICG fluorescence angiography further demonstrated and confirmed the vascular perfusion of the gastric conduit and the optimal site of anastomosis. The patient had an unremarkable postoperative course with no reported anastomotic leakage and stricture formation at 12 months follow-up.

RELEVANCE AND IMPACT

ICG fluorescence angiography represents a feasible and promising tool in assessing viability of esophageal replacement and choosing the optimal site for anastomosis with the proximal esophagus. It can aid in choosing the most appropriate site of anastomosis to prevent ischemia-related complications such as leakage or stricture. This particular case can serve as an initial learning experience to guide surgeons in our institution in the use of ICG fluorescence angiography for esophageal replacements after esophagectomy.

Successful management of gastric remnant necrosis after proximal gastrectomy using a double elementary diet tube: a case report

Background

The stomach has many incoming vessels and is resistant to ischemia due to the rich microvascular network within its submucosal layer. Although reports of gastric remnant necrosis after gastrectomy have been rare, mortality rates remain substantially high when present. A double elementary diet (W-ED) tube, which can be used for both enteral feeding and gastrointestinal tract decompression, has been developed for anastomotic leakage and postoperative nutritional management after upper gastrointestinal surgery. The current report presents a case of gastric remnant necrosis after proximal gastrectomy that was successfully managed through conservative treatment with a W-ED tube.

Case presentation

A 73-year-old male was referred to our hospital for an additional resection after endoscopic submucosal dissection (ESD) for gastric cancer. Endoscopic findings showed an ESD scar on the posterior wall of the upper portion of the stomach, while computed tomography (CT) showed no obvious regional lymph node enlargement and distant metastases. The patient subsequently underwent laparoscopic proximal gastrectomy and esophagogastrostomy but developed candidemia on postoperative day 7. On postoperative day 14, endoscopy revealed gastric ischemic changes around the anastomotic site, suggesting that the patient’s candidemia developed due to gastric necrosis. His vital signs remained normal, while the gastric remnant ischemia was localized. Given that surgery in the presence of candidemia was considered extremely risky, conservative treatment was elected. A W-ED tube was placed nasally, after which enteral feeding was initiated along with gastrointestinal tract decompression. Although the patient subsequently developed anastomotic leakage due to gastric remnant necrosis, local control was achieved and conservative treatment was continued. On postoperative day 52, healing of the gastric remnant necrosis and anastomotic leakage was confirmed, after which the patient started drinking water. Although balloon dilation was required due to anastomotic stenosis, the patient was able to resume oral intake and was discharged on postoperative day 88.

Conclusions

Herein, we present our experience with a case of gastric remnant necrosis after proximal gastrectomy, wherein conservative management was achieved using a W-ED tube. In cases involving high operative risk, the management should be mindful of gastric remnant necrosis as a post-gastrectomy complication.

Validation of quantitative assessment of indocyanine green fluorescent imaging in a one-vessel model

Objectives

Evaluation of intestinal perfusion remains subjective and depends on the surgeon´s individual experience. Intraoperative quality assessment of tissue perfusion with indocyanine green (ICG) fluorescence using a near-infrared camera system has been described in different ways and for different indications. The aim of the present study was to evaluate fluorescent imaging (FI) in the quantitative assessment of intestinal perfusion in a gastric tube model in pigs and to compare the results to results obtained with florescent microspheres (FM), the gold standard for tissue perfusion.

Methods

Seven pigs (56.0±3.0 kg), both males and females, underwent gastric tube formation after transection and ligation of the gastric arteries, except the right gastroepiploic artery, to avoid collateral blood flow.

After baseline assessment (T0), hypotension (T1) was induced by propofol (Karampinis et al 2017) (< 60 mmHg). Then, propofol was paused to obtain normotension (T2, Mean arterial pressure (MAP) 60–90 mmHg). Finally, hypertension (T3, MAP>90 mmHg) was induced by norepinephrine.

Measurements were performed in three regions of interest (ROIs) under standardized conditions: the fundus (D1), corpus (D2), and prepyloric area (D3). Hemodynamic parameters and transit-time flow measurement (TTFM) in the right gastroepiploic artery were continuously assessed. FI, FM and the partial pressure of tissue oxygen (TpO₂) were quantified in each ROI.

Results

The study protocol could successfully be performed during stable hemodynamics. Flow in the gastroepiploic artery measured by transit time flow measurement (TTFM) was related to hemodynamic changes between the measurements, indicating improved blood flow with increasing MAP. The distal part of the gastric tube (D1) showed significantly (p<0.05) impaired perfusion compared to the proximal parts D3 and D2 using FM. ICG-FI also showed the highest values in D3 and the lowest values in D1 at all hemodynamic levels (T1-T3; p<0,05).

Conclusion

Visual and quantitative assessment of gastric tube perfusion is feasible in an experimental setting using ICG-FI. This might be a promising tool for intraoperative assessment during visceral surgery in the future.

Fluorescence Image-Based Evaluation of Gastric Tube Perfusion during Esophagogastrostomy

During esophagectomy and esophagogastrostomy, the prediction of anastomotic leakage relies on the operating surgeon's tactile or visual diagnosis. Therefore, anastomotic leaks are relatively unpredictable, and new intraoperative evaluation methods or tools are essential. A fluorescence imaging system enables visualization over a wide region of interest, and provides intuitive information on perfusion intraoperatively. Surgeons can choose the best anastomotic site of the gastric tube based on fluorescence images in real time during surgery. This technology provides better surgical outcomes when used with an optimal injection dose and timing of indocyanine green.

A Novel Parameter Identified Using Indocyanine Green Fluorescence Angiography may Contribute to Predicting Anastomotic Leakage in Gastric Cancer Surgery

BACKGROUND

Anastomotic leak is one of the most serious postoperative complications, and intraoperative adequate perfusion plays a key role in preventing its development in gastric cancer surgery. This study aimed to investigate the relationships between anastomotic leak and the parameters defined by an assessment of intraoperative anastomotic perfusion using a near-infrared indocyanine green (ICG) fluorescence system and to evaluate the usefulness of this ICG fluorescence assessment in gastric cancer surgery.

METHODS

We retrospectively reviewed data of 100 patients who underwent gastric cancer surgery. In a visual assessment based on fluorescence intensity, we classified ICG fluorescence image patterns as homogeneous, heterogeneous, or faint. In a chronological assessment, the first or second time point of ICG fluorescence appearance on one or the other side of the anastomosis was defined as FT or ST, respectively. The time difference in ICG fluorescence appearance between FT and ST was defined as TD. The relationships between anastomotic leak and the evaluated clinical factors, including the parameters identified by the ICG fluorescence assessment, were evaluated using univariate or multivariate analysis.

RESULTS

Although no signs of leak were found by surgeons' subjective judgments, four patients developed postoperative anastomotic leak of Clavien-Dindo grade III or IV. Multivariate analysis revealed that TD was an independent predictor of anastomotic leak (odds ratio 35.361, 95% confidence interval 1.489-839.923, p = 0.027).

CONCLUSIONS

A novel parameter identified using near-infrared ICG fluorescence assessment may be useful to predict anastomotic leak in gastric cancer surgery.

TRIAL REGISTRATION

UMIN Clinical Trials Registry: #UMIN000030747 ( https://www.umin.ac.jp/ctr/index.htm ).

The Utility of Indocyanine Green Angiography in the Assessment of Perfusion of Gastric Conduit and Proximal Esophageal Stump Against Visual Assessment in Patients Undergoing Esophagectomy: a Prospective Study

Post esophagectomy anastomotic leakage is a crucial factor in determining morbidity and mortality. Good vascularity of the gastric conduit is essential to avoid this complication. This prospective study compares the utility of intraoperative indocyanine green (ICG) fluorescence angiography and visual assessment in assessing the vascularity of gastric conduit and proximal esophageal stump in patients undergoing esophagectomy. Thirteen consecutive patients who underwent esophagectomy for carcinoma middle, lower third esophagus or gastro-esophageal junction from August 2019 to September 2019 were included. Three patients underwent laparoscopic-assisted transhiatal esophagectomy, ten thoraco-laparoscopic-assisted esophagectomy. Reconstruction was done by gastric pull-up via posterior mediastinal route. All patients underwent assessment of perfusion of gastric conduit and proximal esophageal stump by ICG angiography and by visual assessment based on inspection of the color, the palpation of warmth, pulse, and bleeding from the edges. Visual assessment revealed the tip of the gastric conduit was dusky and ischemic in 11 patients, pink and well perfused in two. ICG fluorescence imaging showed inadequate perfusion at the tip of conduit in 12 patients, adequate in one, overall requiring revision in 12 cases. There was a discrepancy in one patient where visual inspection showed adequate perfusion, but ICG disclosed poor vascularity requiring revision of the conduit's tip. Resection of the devitalized portion of the proximal esophageal stump was needed in 5 patients both by visual and by ICG assessment. The median time to appearance of blush from the time of injection of dye was 15 s (10 to 23 s). In all the cases, the pattern of blush was simultaneous, with the concurrent appearance of ICG blush in the gastric conduit and gastro-epiploic arcade. No anastomotic leaks were noted. Visual inspection of the gastric conduit vascularity can underestimate perfusion and hence can compromise resection of the devitalized part. ICG fluorescence imaging is an accurate and promising means to ascertain the vascularity of gastric conduit during an esophagectomy. But its utility needs to be validated in randomized trials.