Indocyanine green fluorescence imaging to reduce the risk of anastomotic leakage in laparoscopic low anterior resection for rectal cancer: a propensity score-matched cohort study. Surg Endosc. 2020;34:202-208. [PMID: 30877565 DOI: 10.1007/s00464-019-06751-9]

The role of ICG NIRL fluorescence imaging in the surgical treatment of digestive system tumors (Review)

Indocyanine green (ICG) is a relatively non‑toxic fluorescent dye with a history of safe use, which has fueled the development of new applications for ICG. Research on the use of ICG near‑infrared light (NIRL) fluorescence imaging during oncologic surgery has increased, revealing its role in tumor identification and localization, lymph node navigational resection and blood perfusion assessment. The purpose of the present review was to provide a comprehensive overview of advances in the clinical application of ICG NIRL fluorescence imaging during gastrointestinal tumor surgery. The present review discusses the techniques, outcomes, limitations and key considerations necessary for clinical practice, aiming to provide a valuable resource for professionals in the field.

Impact of Low Ligation on Bowel Perfusion and Anastomotic Leakage in Minimally Invasive Rectal Cancer Surgery: A Post Hoc Analysis of a Randomized Controlled Trial

BACKGROUND

Whether the level of the inferior mesenteric artery ligation affects the incidence of anastomotic leakage remains unclear.

OBJECTIVE

To assess the impact of the level of inferior mesenteric artery ligation on blood flow to the anastomotic site and the incidence of anastomotic leakage using indocyanine green fluorescence imaging.

DESIGN

A post hoc analysis of the EssentiAL trial.

SETTINGS

This study was conducted at 41 tertiary referral centers in Japan.

PATIENTS

A total of 839 patients with rectal cancer (<12 cm from the anal verge) were included.

MAIN OUTCOME MEASURES

The incidence of anastomotic leakage and perfusion status were compared between the high and low ligation groups.

RESULTS

The median fluorescence time was similar at 25 seconds in both groups (p = 0.74). Although no statistical difference was noted, the high ligation group was more likely to have greater outliers in fluorescence time compared to the low ligation group. The high ligation group demonstrated higher poor perfusion rates than the low ligation group (2.8% vs 1.5%). In the high ligation group, anastomotic leakage occurred in 1 case of poor perfusion where additional resection was not performed by the surgeon's intraoperative judgment. In addition, the additional resection rate nearly doubled with the use of indocyanine green fluorescence imaging. After propensity score matching (129 patients per group), the overall anastomotic leakage rate was 13.2% in the high ligation group and 10.9% in the low ligation group ( p = 0.57).

LIMITATIONS

This study was a post hoc analysis, the sample size was small, and the anastomosis methods varied.

CONCLUSIONS

The level of inferior mesenteric artery ligation did not affect blood flow at the anastomotic site or the incidence of anastomotic leakage statistically, but assessing bowel perfusion using indocyanine green fluorescence imaging can offer clinical benefits, optimizing patient outcomes. See Video Abstract .

TRIAL REGISTRATION

The Japan Registry of Clinical Trials (jRCTs-CRB3180007), the Japanese Clinical Trials Registry (UMIN-CTR000030240).

IMPACTO DE LA LIGADURA BAJA EN LA PERFUSIN INTESTINAL Y LA FUGA ANASTOMTICA EN LA CIRUGA MNIMAMENTE INVASIVA DEL CNCER RECTAL UN ANLISIS POST HOC DE UN ENSAYO CONTROLADO ALEATORIZADO

ANTECEDENTES:No está claro si el nivel de la ligadura de la arteria mesentérica inferior afecta la incidencia de fuga anastomótica.OBJETIVO:Evaluar el impacto del nivel de ligadura de la arteria mesentérica inferior en el flujo sanguíneo al sitio de la anastomosis y la incidencia de fuga anastomótica mediante imágenes de fluorescencia con verde de indocianina.DISEÑO:Análisis post hoc del ensayo EssentiAL.ESCENARIO:Este estudio se realizó en 41 centros de referencia terciarios en Japón.PACIENTES:839 pacientes con cáncer rectal (<12 cm desde el márgen anal).PRINCIPALES MEDIDAS DE RESULTADOS:Se compararon la incidencia de fuga anastomótica y el estado de perfusión entre los grupos de ligadura alta y baja.RESULTADOS:El tiempo de fluorescencia medio fue similar a 25 segundos en ambos grupos (p = 0.74). Aunque no se observó ninguna diferencia estadística, el grupo de ligadura alta tuvo más probabilidades de tener mayores valores atípicos en el tiempo de fluorescencia en comparación con el grupo de ligadura baja. El grupo de ligadura alta demostró tasas de perfusión deficiente más altas que el grupo de ligadura baja (2.8 % frente a 1.5 %). En el grupo de ligadura alta, se produjo una fuga anastomótica en un caso de perfusión deficiente en el que no se realizó una resección adicional según el criterio intraoperatorio del cirujano. Además, la tasa de resección adicional casi se duplicó con el uso de imágenes de fluorescencia con verde de indocianina. Después de la comparación por puntaje de propensión (129 pacientes por grupo), la tasa general de fuga anastomótica fue del 13.2 % en el grupo de ligadura alta y del 10.9 % en el grupo de ligadura baja ( p = 0.57).LIMITACIONES:Este estudio fue un análisis post hoc, el tamaño de la muestra fue pequeño y los métodos de anastomosis variaron.CONCLUSIONES:El nivel de ligadura de la arteria mesentérica inferior no afectó estadísticamente el flujo sanguíneo en el sitio de la anastomosis ni la incidencia de fuga anastomótica, pero la evaluación de la perfusión intestinal mediante imágenes de fluorescencia con verde de indocianina puede ofrecer beneficios clínicos, optimizando los resultados del paciente. (Traducción-Dr. Jorge Silva Velazco)REGISTRO DEL ENSAYO:Registro japonés de ensayos clínicos (jRCTs-CRB3180007), Registro japonés de ensayos clínicos (UMIN-CTR000030240).

Advancement of indocyanine green fluorescence imaging technology in laparoscopic surgery for rectal cancer

Indocyanine green fluorescence imaging technology has been increasingly utilized in rectal surgery in recent years. As a safe tracer, indocyanine green can facilitate lymph node tracing, assess the blood supply at anastomotic sites, and localize tumour lesions during laparoscopic surgery, thereby resulting in favourable outcomes. This technology helps surgeons to achieve more precise diagnoses and treatments in laparoscopic procedures, thus ultimately benefiting patients. However, the current application of indocyanine green fluorescence imaging technology still lacks standardized regulations, and certain effects remain contentious. This study provides a comprehensive review of the application of indocyanine green in laparoscopic surgery for rectal cancer based on the pertinent literature.

Role of Indocyanine Green Angiography to Assess Intra-operative Bowel Vascularity and its Association with Post-operative Outcome in Robot-assisted Rectal Resection: a Prospective Indian Cohort Study

Adequate intestinal perfusion is one of the critical factors influencing anastomotic leak (AL) in colorectal surgery. The use of indocyanine green fluoroscence angiography (ICG-FA) intra-operatively to ensure optimal perfusion is being increasingly used. This prospective study aimed to assess the role of ICG-FA in robot-assisted surgery for rectal cancer. This was a prospective cohort study carried out between July 2019 and July 2023, comprising patients undergoing elective robot-assisted rectal resection. The primary objective was to determine the role of ICG-FA in assessing bowel vascularity and in deciding the transection point of the bowel. The secondary objective was to assess the effect of ICG-FA on the post-operative outcomes, and also the effect of the various variables on the ICG staining grade. A total of 50 patients were included. Sixty percent of the patients received pre-operative radiotherapy, including short-course radiotherapy (SCRT) and long-course concurrent chemoradiation (LCRT). A change in transection line based on a less than normal ICG-FA grade was done in 11 patients (22%). Post-operatively, AL was present in 8 patients, out of whom 5 underwent re-operation. Administration of pre-operative RT was the only factor significantly associated with post-operative AL (p < 0.05). The present study showed that a change in the transection point based on the intra-operative ICG-FA was made in 22% of the patients. ICG-FA could hence be used as a potential adjunct to the operative surgeon in assessing the bowel vascularity in a minimally invasive approach like robotic or laparoscopic surgery.

Impact of indocyanine green fluorescence angiography on surgeon action and anastomotic leak in colorectal resections. A systematic review and meta-analysis

BACKGROUND

Indocyanine green fluorescence angiography (ICGFA) during colorectal surgery either reassures surgeons regarding intestinal perfusion sufficiency or prompts changed surgical strategy by indicating unsuspected insufficiency. This study describes existing evidence supporting ICGFA use in colorectal surgery, particularly regarding impact on intraoperative decisions.

METHODS

Searches were performed on PubMed, ScienceDirect, Scopus, Web of Science, Cochrane Collaboration databases on 5th December 2023, updated to 19th August 2024. Full English language publications of clinical studies in human patients undergoing colorectal resection with primary anastomosis with the use of ICGFA to assess bowel perfusion intraoperatively, with a control group, were included. Pooling of anastomotic leak (AL) rates was performed for primary outcome analysis with odds ratio (OR) and number-needed-to-treat (NNT) calculated regarding leak reduction.

RESULTS

45 studies comprising 14,333 patients were included, with 7 randomised controlled trials (2911 patients). Overall, AL rate was 6.8%, 4.5% with ICGFA and 8.5% without (OR:0.47, p < 0.001, NNT 23), increasing to 9.5%, 7.5% and 11.6%, respectively, in randomised controlled trials (OR:0.62, p < 0.01, NNT 25). In rectal resections, AL rate was 4.7% with ICGFA vs 11.5% without (OR: 0.38, p < 0.0001). 26 studies performed ICGFA before and after anastomosis formation and 19 used ICGFA only prior to bowel transection, with no significant difference of AL rate reduction on subgroup testing. ICGFA prompted a change in surgical plan in 8.4% of thirty-four studies reporting this. Interestingly, in these studies, leak rates overall were 3.7% when ICGFA matched surgeon judgement versus 5.7% when it prompted change (OR 0.51, p < 0.0025), versus 7.7% without (OR 0.45, p < 0.0001). In rectal resections, these figures were 5%, 8.8% (OR 0.42, p = 0.01) and 12.0% (OR0.39, p < 0.0001), respectively.

CONCLUSIONS

ICGFA colorectal perfusion assessment is associated with lower anastomotic leak rates, especially when confirming surgeons' judgement, and may so stratify patients post-operatively regarding subsequent anastomotic leak rate.

Indocyanine green fluorescence-guided surgery in the emergency setting: the WSES international consensus position paper

BACKGROUND

Decision-making in emergency settings is inherently complex, requiring surgeons to rapidly evaluate various clinical, diagnostic, and environmental factors. The primary objective is to assess a patient's risk for adverse outcomes while balancing diagnoses, management strategies, and available resources. Recently, indocyanine green (ICG) fluorescence imaging has emerged as a valuable tool to enhance surgical vision, demonstrating proven benefits in elective surgeries.

AIM

This consensus paper provides evidence-based and expert opinion-based recommendations for the standardized use of ICG fluorescence imaging in emergency settings.

METHODS

Using the PICO framework, the consensus coordinator identified key research areas, topics, and questions regarding the implementation of ICG fluorescence-guided surgery in emergencies. A systematic literature review was conducted, and evidence was evaluated using the GRADE criteria. A panel of expert surgeons reviewed and refined statements and recommendations through a Delphi consensus process, culminating in final approval.

RESULTS

ICG fluorescence imaging, including angiography and cholangiography, improves intraoperative decision-making in emergency surgeries, potentially reducing procedure duration, complications, and hospital stays. Optimal use requires careful consideration of dosage and timing due to limited tissue penetration (5-10 mm) and variable performance in patients with significant inflammation, scarring, or obesity. ICG is contraindicated in patients with known allergies to iodine or iodine-based contrast agents. Successful implementation depends on appropriate training, availability of equipment, and careful patient selection.

CONCLUSIONS

Advanced technologies and intraoperative navigation techniques, such as ICG fluorescence-guided surgery, should be prioritized in emergency surgery to improve outcomes. This technology exemplifies precision surgery by enhancing minimally invasive approaches and providing superior real-time evaluation of bowel viability and biliary structures-areas traditionally reliant on the surgeon's visual assessment. Its adoption in emergency settings requires proper training, equipment availability, and standardized protocols. Further research is needed to evaluate cost-effectiveness and expand its applications in urgent surgical procedures.

Risk factors for anastomotic leakage in rectal cancer surgery reflecting current practices

PURPOSE

In recent years, major advancements have been made in rectal cancer surgery with the introduction of new techniques such as robotic surgery and indocyanine green fluorescence imaging (ICG-FI). This study aimed to evaluate the comprehensive risk factors for anastomotic leakage (AL) following rectal cancer surgery, incorporating recently introduced techniques and other existing factors, to reflect current practices.

METHODS

A retrospective analysis was conducted of 304 patients who underwent either robotic or laparoscopic anterior resection between January 2019 and December 2023. The study analyzed patient, tumor, and surgical factors, with AL defined by clinical or radiological findings requiring intervention within 30 days after surgery.

RESULTS

A univariate analysis indicated that moderate or severe anemia and the non-use of ICG-FI were strongly associated with AL. A multivariate analysis identified moderate or more severe anemia (hemoglobin ≤10.9 g/dL for males and ≤9.9 g/dL for females) (odds ratio [OR]: 9.94, p = 0.002) and non-use of ICG-FI (OR: 10.40, p < 0.001) as independent risk factors for AL.

CONCLUSION

Moderate or severe anemia and absence of ICG-FI were found to significantly increase the risk of AL. Preoperative anemia correction and the routine use of ICG-FI may help mitigate this risk, thus suggesting the need for further research in these areas.

Does indocyanine green fluorescence angiography reduce the risk of anastomotic leaks in colorectal resections? A systematic review and meta-analysis of randomized controlled trials

Anastomotic leaks are a significant complication in colorectal surgery. Indocyanine green fluorescence angiography (ICG-FA) has been suggested as a method to reduce the risk. This meta-analysis aims to evaluate the effect of ICG-FA on reducing anastomotic leaks in colorectal surgery. This study follows PRISMA guidelines and is registered on PROSPERO (CRD42022370748). We conducted a comprehensive search of multiple databases and registers for randomized controlled trials (RCTs) comparing ICG-FA with standard methods in colorectal surgery. Data extraction and quality assessment were performed by two independent reviewers, with a third resolving disputes. Odds ratios (OR) and mean differences (MD) were calculated using comprehensive meta-analysis software, version 3. Heterogeneity and publication bias were assessed, and a sensitivity analysis was performed. The analysis included five RCTs with a total of 1369 patients from four countries. The ICG-FA was associated with a 45% reduction in the risk of overall anastomotic leaks (OR: 0.550, p = 0.012). Subgroup analysis showed a 47% reduction in leaks for low anastomoses (OR: 0.53, p = 0.143) and a 69% reduction in grade A leaks (OR: 0.31, p = 0.008). No significant effects were observed for grade B and C leaks, blood loss, surgery duration, hospital stay, mortality, postoperative ileus, reoperation, or surgical site infections. ICG-FA significantly reduces the overall risk of anastomotic leaks, especially grade A leaks, and shows a trend towards fewer leaks in low anastomosis. No significant impact was found on secondary outcomes. Further RCTs are needed to confirm these findings.

Indocyanine green in left side colorectal surgery segmental resection to decrease anastomotic leak: A parallel retrospective cohort study of 115 patients

BACKGROUND

We investigated the impact of Indocyanine Green (ICG) angiography on reducing anastomotic leakage (AL) after elective left segmental colon resection, including transverse resection. While ICG is widely used in colorectal surgery to assess vascularization, its true effect on AL, particularly in left segmental resections, remains unclear.

STUDY DESIGN

This retrospective, monocentric cohort study included patients undergoing left and transverse colon resection from January 2017 to July 2023. Patients were divided into ICG and no-ICG groups. The primary outcome was AL, with secondary outcomes including postoperative morbidity and length of stay.

RESULTS

Of the 115 patients enrolled, 53 received ICG and 63 did not. AL occurred in 6 patients in the no-ICG group, but none in the ICG group. No significant correlation was found between ICG use and other confounding factors. Postoperative length of stay was also shorter in the ICG group.

CONCLUSIONS

The use of ICG was associated with a reduction in AL, with no cases in the ICG group. These findings suggest a potential benefit of ICG, warranting confirmation in future large-scale studies.

CLINICAL TRIAL REGISTRATION

clinicaltrial.gov (NCT05981937).

Drainage Fluid Amylase as a Biomarker for the Detection of Anastomotic Leakage After Low Anterior Resection of Rectal Cancer: A Two-center Study

Aim

This study aimed to investigate the utility of measuring amylase levels in drainage fluid (DFA) for early, non-invasive detection of anastomotic leakage (AL) in undergoing low anterior resection (LAR) for rectal cancer.

Patients and Methods

This prospective observational cohort study analyzed drainage fluid samples from patients who underwent LAR for rectal cancer at two medical centers between February 2021 and December 2023. DFA levels were measured on postoperative days (PODs) 1, 3, and 5. AL was confirmed by clinical evidence and radiological imaging. Statistical analyses were performed to evaluate the diagnostic performance of DFA.

Results

Of 120 LAR cases, AL occurred in five (4.16%). DFA levels on POD 3 and 5 were significantly higher in the AL than in the non-AL group (p<0.0001). DFA on POD 5 had the highest diagnostic accuracy for early AL detection, with an area under the curve of 0.99, achieving 100% sensitivity and 99.5% specificity at a cutoff of 846 U/l. A DFA >846 U/l predicted AL with negative predictive and positive predictive values of 83.3% and 100%, respectively, on POD 5.

Conclusion

Measuring DFA is a non-invasive, simple and cost-effective method for early AL detection in patients with rectal cancer undergoing LAR. Our findings also suggested that drain placement may be useful for the early detection of AL through DFA measurement.

Efficacy and Safety of Fluorescence-Guided Surgery Compared to Conventional Surgery in the Management of Colorectal Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

The use of fluorescence agents and imaging systems is a promising adjunct in the surgical management of colorectal cancer. This systematic review and meta-analysis aimed to assess the safety and efficacy of fluorescence-guided surgery in the management of colorectal cancer, with a comparison to conventional (non-fluorescence-guided) surgery.

METHODS

A literature search of MEDLINE, Embase, Emcare, and CINAHL databases was performed for studies that reported data on the outcomes of fluorescence-guided surgery, with or without a comparison group undergoing conventional surgery, for colorectal cancer between January 2000 and January 2024. A meta-analysis was performed using random-effect models, and between-study heterogeneity was assessed.

RESULTS

35 studies of 3217 patients with colorectal cancer were included: 26 studies (964 patients) reported on fluorescence-guided surgery and 9 studies (2253 patients) reported on fluorescence versus conventional surgery. The weighted mean of the cancer detection rate of fluorescence-guided surgery was 71% (95% CI 0.55-0.85), with no significant difference in lymph node yield ratio (WMD -0.04; 95% CI -0.10-0.02; p = 0.201) between fluorescence and conventional surgery groups. There was a significantly lower blood loss (WMD -4.38; 95% CI -7.05--1.70; p = 0.001) and complication rate (WMD -0.04; 95% CI -0.07-0.00; p = 0.027) in the fluorescence-guided surgery group, with a potentially lower anastomotic leak rate (WMD -0.05; 95% CI -0.10-0.01; p = 0.092).

CONCLUSIONS

Fluorescence-guided surgery is a safe and effective approach in the management of colorectal cancer, potentially reducing blood loss and complications. Further randomised controlled trials are required comparing fluorescence-guided surgery with conventional surgery to determine its prognostic benefit and where it should precisely fit within the management pathway of colorectal cancer.

The use of indocyanine green for colorectal anastomoses: a systematic review and meta-analysis

INTRODUCTION

Anastomotic leak is a relatively common and debilitating complication. Colorectal leak rates vary widely in the literature, ranging from 1% to 20%. In modern surgical practice, there is much emphasis on the use of indocyanine green (ICG). This is a fluorescent dye administered intravenously to locate and predict an adequate line of anastomosis. We sought to analyse the current literature and supporting evidence behind the use of ICG in the context of elective colorectal surgery.

METHODS

A literature search was conducted for papers published between January 1991 and December 2022 concerning the use of ICG in colorectal surgery. Data on anastomotic leak, overall complication rate, operative time and involvement of artificial intelligence (AI) were compared.

RESULTS

A total of 24 studies were selected, including 3 randomised controlled trials. There was an anastomotic leak rate of 4.3% in cases with ICG administration compared with 9.5% in the control group (p<0.00001). Seven studies mentioned overall complication rates. These were lower in the ICG cohort than in the control group (15.5% vs 24.5%). There was no significant correlation between ICG use and operative time (p=0.78). Five studies looked at AI, with results suggesting that use of AI leads to much better accuracy in ICG metric analysis. However, the current literature is still inconclusive.

CONCLUSIONS

While there is strong evidence behind ICG use in the existing literature, more randomised controlled trials are required for better recommendations. AI in ICG metric interpretation has proved to be difficult owing to interpatient variability. Nevertheless, new data suggest better understanding and standardisation.

Advancing indocyanine green fluorescence flap perfusion assessment via near infrared signal quantification

Introduction

Intraoperative indocyanine green fluorescence angiography (ICGFA) perfusion assessment has been demonstrated to reduce complications in reconstructive surgery. This study sought to advance ICGFA flap perfusion assessment via quantification methodologies.

Method

Patients undergoing pedicled and free flap reconstruction were subjected to intraoperative ICGFA flap perfusion assessment using either an open or endoscopic system. Patient demographics, clinical impact of ICGFA and outcomes were documented. From the ICGFA recordings, fluorescence signal quality, as well as inflow/outflow milestones for the flap and surrounding (control) tissue were computationally quantified post hoc and compared on a region of interest (ROI) level. Further software development intended full flap quantification, metric computation and heatmap generation.

Results

Fifteen patients underwent ICGFA assessment at reconstruction (8 head and neck, 6 breast and 1 perineum) including 10 free and 5 pedicled flaps. Visual ICGFA interpretation altered on-table management in 33.3% of cases, with flap edges trimmed in 4 and a re-anastomosis in 1 patient. One patient suffered post-operative flap dehiscence. Laparoscopic camera use proved feasible but recorded a lower quality signal than the open system.Using established and novel metrics, objective ICGFA signal ROI quantification permitted perfusion comparisons between the flap and surrounding tissue. Full flap assessment feasibility was demonstrated by computing all pixels and subsequent outputs summarisation as heatmaps.

Conclusion

This trial demonstrated the feasibility and potential for ICGFA with operator based and quantitative flap perfusion assessment across several reconstructive applications. Further development and implementation of these computational methods requires technique and device standardisation.

Blood perfusion assessment by near-infrared fluorescence angiography of epiploic appendages in prevention of anastomotic leakage after laparoscopic intersphincteric resection for ultra-low rectal cancer: a case-matched study

BACKGROUND

The role of intraoperative near-infrared fluorescence angiography with indocyanine green in reducing anastomotic leakage (AL) has been demonstrated in colorectal surgery, however, its perfusion assessment mode, and efficacy in reducing anastomotic leakage after laparoscopic intersphincteric resection (LsISR) need to be further elucidated.

AIM

Aim was to study near-infrared fluorescent angiography to help identify bowel ischemia to reduce AL after LsISR.

MATERIAL AND METHODS

A retrospective case-matched study was conducted in one referral center. A total of 556 consecutive patients with ultra-low rectal cancer including 140 patients with fluorescence angiography of epiploic appendages (FAEA)were enrolled. Perfusion assessment by FAEA in the monochrome fluorescence mode. Patients were divided into two groups based on perfusion assessment by FAEA. The primary endpoint was the AL rate within 6 months, and the secondary endpoint was the structural sequelae of anastomotic leakage (SSAL).

RESULTS

After matching, the study group (n = 109) and control group (n = 190) were well-balanced. The AL rate in the FAEA group was lower before (3.6% vs. 10.1%, P = 0.026) and after matching (3.7% vs. 10.5%, P = 0.036). Propensity scores matching analysis (OR 0.275, 95% CI 0.035-0.937, P 0.039), inverse probability of treatment weighting (OR 0.814, 95% CI 0.765-0.921, P 0.002), and regression analysis (OR 0.298, 95% CI 0.112-0.790, P = 0.015), showed that FAEA was an independent protector factor for AL. This technique can significantly shorten postoperative hospital stay [9 (6-13) vs. 10 (8-13), P = 0.024] and reduce the risk of SSAL (1.4% vs. 6.0%, P = 0.029).

CONCLUSIONS

Perfusion assessment by FAEA can achieve better visualization in LsISR and reduce the incidence of AL, subsequently avoiding SSAL after LsISR.

How to objectively evaluate the impact of image-guided surgery technologies

PURPOSE

This manuscript aims to provide a better understanding of methods and techniques with which one can better quantify the impact of image-guided surgical technologies.

METHODS

A literature review was conducted with regard to economic and technical methods of medical device evaluation in various countries. Attention was focused on applications related to image-guided interventions that have enabled procedures to be performed in a minimally invasive manner, produced superior clinical outcomes, or have become standard of care.

RESULTS

The review provides examples of successful implementations and adoption of image-guided surgical techniques, mostly in the field of neurosurgery. Failures as well as newly developed technologies still undergoing cost-efficacy analysis are discussed.

CONCLUSION

The field of image-guided surgery has evolved from solely using preoperative images to utilizing highly specific tools and software to provide more information to the interventionalist in real time. While deformations in soft tissue often preclude the use of such instruments outside of neurosurgery, recent developments in optical and radioactive guidance have enabled surgeons to better account for organ motion and provide feedback to the surgeon as tissue is cut. These technologies are currently undergoing value assessments in many countries and hold promise to improve outcomes for patients, surgeons, care teams, payors, and society in general.

C-reactive protein-to-albumin ratio as a risk factor for anastomotic leakage after anterior resection for rectal cancer with intraoperative use of indocyanine green fluorescence imaging

INTRODUCTION

Indocyanine green fluorescence imaging (ICG-FI) reduces anastomotic leakage (AL) in rectal cancer surgery. However, no studies investigating risk factors for anastomotic leakage specific to the group using ICG-FI have ever previously been conducted. The purpose of this retrospective multicenter study was to ascertain the risk factors for AL in the group using ICG-FI.

METHODS

A total of 638 patients who underwent laparoscopic or robotic anterior resection for rectal cancer between April 2018 and March 2023 were included in this study. Patients were divided into two groups: the ICG-FI group (n = 269) and the non-ICG-FI group (n = 369) for comparative analysis. The effects of clinicopathological and treatment-related factors on AL in the ICG-FI group were evaluated using both univariate and multivariate analyses.

RESULTS

The incidence of AL in the ICG-FI group was 4.8%. Although there was no significant difference in the incidence of AL between the two groups, it was observed to be lower in the ICG-FI group. A multivariate analysis revealed a preoperative C-reactive protein-to-albumin ratio (CAR) ≥ 0.049 (odds ratio, 3.73; 95% confidence interval, 1.01-13.70; p = 0.048) as an independent risk factor for AL in the ICG-FI group.

CONCLUSIONS

In this study, CAR was the only identified risk factor for AL in the ICG-FI group. It was suggested that CAR could be a criterion for early surgical intervention, prior to the escalation of risks, or for considering interventions such as diverting stoma creation.

Use of the Staple Line Reinforcement Tool to Reduce the Rate and Completely Avoid Anastomotic Leakage in Functional End-to-End Anastomosis

Background In our hospital, anastomotic leakage (AL) is observed in approximately 2% of functional end-to-end anastomosis (FEEA) cases annually. It is also usually observed at the staple line of the entry hole closure in several reoperation cases. This study aimed to investigate whether AL would occur in FEEA using a new staple line reinforcement tool, ECHELON ENDOPATH® Staple Line Reinforcement (SLR) (Ethicon, Raritan, NJ, USA). Methods A total of 380 patients (400 anastomoses performed from September 2021, when SLR use began, to the end of February 2024) were compared retrospectively, with a total of 459 patients (469 anastomoses performed from April 2019 to August 2021), the same period before SLR was initiated. In the SLR group, ECHELON FLEX® (Ethicon) 60 mm and GST® system (Ethicon) cartridges were used as stapling devices. A p-value of <0.05 was considered statistically significant. Results No AL was observed in the SLR group, with a significant difference between the SLR and non-SLR groups (p=0.0021). By anastomotic organ, the AL rate significantly decreased for small intestine-colon anastomosis (p=0.023), but there was no significant difference in small intestine-small intestine anastomosis (p=0.061) or colon-colon anastomosis (p=0.35) between groups. Conclusion Reinforcing the staple line using SLR in FEEA may reduce the AL rate. Although AL has not been observed, we will continue to investigate its causes should it occur in the future.

Real time organ hypoperfusion detection using Indocyanine Green in a piglet model

BACKGROUND

Preserving sufficient oxygen supply to the tissue is fundamental for maintaining organ function. However, our ability to identify those at risk and promptly recognize tissue hypoperfusion during abdominal surgery is limited. To address this problem, we aimed to develop a new method of perfusion monitoring that can be used during surgical procedures and aid surgeons' decision-making.

METHODS

In this experimental porcine study, thirteen subjects were randomly assigned one organ of interest [stomach (n = 3), ascending colon (n = 3), rectum (n = 3), and spleen (n = 3)]. After baseline perfusion recordings, using high-frequency, low-dose bolus injections with weight-adjusted (0.008 mg/kg) ICG, organ-supplying arteries were manually and completely occluded leading to hypoperfusion of the target organ. Continuous organ perfusion monitoring was performed throughout the experimental conditions.

RESULTS

After manual occlusion of pre-selected organ-supplying arteries, occlusion of the peripheral arterial supply translated in an immediate decrease in oscillation signal in most organs (3/3 ventricle, 3/3 ascending colon, 3/3 rectum, 2/3 spleen). Occlusion of the central arterial supply resulted in a further decrease or complete disappearance of the oscillation curves in the ventricle (3/3), ascending colon (3/3), rectum (3/3), and spleen (1/3).

CONCLUSION

Continuous organ-perfusion monitoring using a high-frequency, low-dose ICG bolus regimen can detect organ hypoperfusion in real-time.

Fluorescence and tracers in surgery: the coming future

The revolution that we are seeing in the world of surgery will determine the way we understand surgical approaches in coming years. Since the implementation of minimally invasive surgery, innovations have constantly been developed to allow the laparoscopic approach to go further and be applied to more and more procedures. In recent years, we have been in the middle of another revolutionary era, with robotic surgery, the application of artificial intelligence and image-guided surgery. The latter includes 3D reconstructions for surgical planning, virtual reality, holograms or tracer-guided surgery, where ICG-guided fluorescence has provided a different perspective on surgery. ICG has been used to identify anatomical structures, assess tissue perfusion, and identify tumors or tumor lymphatic drainage. But the most important thing is that this technology has come hand in hand with the potential to develop other types of tracers that will facilitate the identification of tumor cells and ureters, as well as different light beams to identify anatomical structures. These will lead to other types of systems to assess tissue perfusion without the use of tracers, such as hyperspectral imaging. Combined with the upcoming introduction of ICG quantification, these developments represent a real revolution in the surgical world. With the imminent implementation of these technological advances, a review of their clinical application in general surgery is timely, and this review serves that aim.

Consensus conference statement on fluorescence-guided surgery (FGS) ESSO course on fluorescence-guided surgery

BACKGROUND

Fluorescence-guided surgery (FGS) has emerged as an innovative technique with promising applications in various surgical specialties. However, clinical implementation is hampered by limited availability of evidence-based reference work supporting the translation towards standard-of-care use in surgical practice. Therefore, we developed a consensus statement on current applications of FGS.

METHODS

During an international FGS course, participants anonymously voted on 36 statements. Consensus was defined as agreement ≥70% with participation grade of ≥80%. All participants of the questionnaire were stratified for user and handling experience within five domains of applicability (lymphatics & lymph node imaging; tissue perfusion; biliary anatomy and urinary tracts; tumor imaging in colorectal, HPB, and endocrine surgery, and quantification and (tumor-) targeted imaging). Results were pooled to determine consensus for each statement within the respective sections based on the degree of agreement.

RESULTS

In total 43/52 (81%) course participants were eligible as voting members for consensus, comprising the expert panel (n = 12) and trained users (n = 31). Consensus was achieved in 17 out of 36 (45%) statements with highest level of agreement for application of FGS in tissue perfusion and biliary/urinary tract visualization (71% and 67%, respectively) and lowest within the tumor imaging section (0%).

CONCLUSIONS

FGS is currently established for tissue perfusion and vital structure imaging. Lymphatics & lymph node imaging in breast cancer and melanoma are evolving, and tumor tissue imaging holds promise in early-phase trials. Quantification and (tumor-)targeted imaging are advancing toward clinical validation. Additional research is needed for tumor imaging due to a lack of consensus.

A Novel Fluorescence-Based Leak Test Method for Rectal Anastomoses Using Aerosolized Indocyanine Green

BACKGROUND

The intraoperative air leak test is commonly performed during rectal surgery to evaluate anastomotic integrity. However, its drawbacks include occasional difficulties in visualizing the exact point of the leak while maintaining the pelvis under saline, the need for repeat testing to identify the leak point, and a lack of continuous visualization of the leak point.

OBJECTIVE

To evaluate the feasibility and clinical applicability of using aerosolized indocyanine green, a fluorescent tracer, for detecting rectal anastomotic leakage.

DESIGN

Animal preclinical study.

SETTING

Animal laboratory at Kagawa University.

PATIENTS

Six healthy adult female beagles were included.

INTERVENTIONS

An anastomotic leakage model with a single air leak point was created in each dog. Indocyanine green was aerosolized using a nebulizer kit with a stream of carbon dioxide flowing at 1.5 to 2.0 L/min. The aerosol was administered into the rectum transanally, and laparoscopic observations were performed.

MAIN OUTCOME MEASURES

Air leak points were observed using a near-infrared fluorescence laparoscope, after which the presence of corresponding indocyanine green fluorescence was verified.

RESULTS

Aerosolized indocyanine green was visualized laparoscopically at all anastomosis sites but not elsewhere. The median time from the administration of the aerosol to its visualization was 4.5 seconds. Pathological examinations were performed 4 weeks postsurgery in all dogs, and no histological abnormalities related to aerosolized indocyanine green administration were observed at the anastomosis sites.

LIMITATIONS

The leak points were surgically created and did not occur naturally.

CONCLUSIONS

Visualization of air leaks at the sites of rectal anastomosis was laparoscopically achievable by administering aerosolized indocyanine green transanally into the rectum in our canine model. This novel fluorescent leak test could be a valid alternative to established methods.

Analysis of effect of colonoscopy combined with laparoscopy in the treatment of colorectal tumors

BACKGROUND

Colorectal cancer is one of the most common digestive tract tumors.

OBJECTIVE

To evaluate the feasibility and safety of laparoscopic colorectal cancer surgery.

METHODS

This study retrospectively analyzed early postoperative clinical data of 48 patients with colorectal cancer treated in our hospital between 2015 and 2021, of which 21 underwent laparoscopic colorectal surgery, and 27 underwent laparotomy. There was no significant difference in clinical data. Patients were included if they had colorectal cancer (confirmed by colonoscopy and biopsy pathological examination before surgery), were evaluated for possible radical surgery before surgery, and had no intestinal obstruction, tumor invasion of adjacent organs (by digital rectal examination and preoperative abdominal color Doppler ultrasound, CT confirmed) and no other history of abdominal surgery. Using the method of clinical control study, operation time, intraoperative blood loss, postoperative general condition, surgical lymph node removal (postoperative pathology), surgical complications, gastrointestinal function recovery, surgical before and after blood glucose, body temperature, white blood cells, pain visual analog scale (VAS) and other conditions were compared and analyzed to determine feasibility and safety of laparoscopic surgery for colorectal cancer.

RESULTS

Colorectal cancer was successfully removed by laparoscopic radical resection without any significant problems or surgical fatalities. Age, gender, tumor location, stage, and duration of surgery did not differ between laparoscopic and laparotomy operations. Compared to laparotomy, postoperative eating, bowel movements, and blood sugar levels improved. Variations in the length of surgically removed specimens after VAS measurements revealed open and laparoscopic operations. The overall lymph node count was 10.8 ± 1.6, with no variation between the two techniques.

CONCLUSION

Laparoscopic colorectal cancer radical surgery is safe and feasible. Also, it has the advantages of minimally invasive surgery. Laparoscopic colorectal cancer radical surgery can comply with the principles of oncology revolutionary.

Dye-free visualisation of intestinal perfusion using laser speckle contrast imaging in laparoscopic surgery: a prospective, observational multi-centre study

INTRODUCTION

Intraoperative perfusion imaging may help the surgeon in creating the intestinal anastomoses in optimally perfused tissue. Laser speckle contrast imaging (LSCI) is such a perfusion visualisation technique that is characterized by dye-free, real-time and continuous imaging. Our aim is to validate the use of a novel, dye-free visualization tool to detect perfusion deficits using laparoscopic LSCI.

METHODS

In this multi-centre study, a total of 64 patients were imaged using the laparoscopic laser speckle contrast imager. Post-operatively, surgeons were questioned if the additional visual feedback would have led to a change in clinical decision-making.

RESULTS

This study suggests that the laparoscopic laser speckle contrast imager PerfusiX-Imaging is able to image colonic perfusion. All images were clear and easy to interpret for the surgeon. The device is non-disruptive of the surgical procedure with an average added surgical time of 2.5 min and no change in surgical equipment. The potential added clinical value is accentuated by the 17% of operating surgeons indicating a change in anastomosis location. Further assessment and analysis of both white light and PerfusiX perfusion images by non-involved, non-operating surgeons showed an overall agreement of 80%.

CONCLUSION

PerfusiX-Imaging is a suitable laparoscopic perfusion imaging system for colon surgery that can visualize perfusion in real-time with no change in surgical equipment. The additional visual feedback could help guide the surgeons in placing the anastomosis at the most optimal site.

Short-term outcomes associated with the use of a new powered circular stapler for rectal reconstructions: a retrospective study comparing it to manual circular staplers using inverse probability of treatment weight analysis

BACKGROUND

The most common postoperative complication in malignant rectal surgery is anastomotic leakage (AL). AL after anterior or low anterior resection in rectal tumors is a fatal postoperative complication. Recently, the first automated suture circular stapler, which is expected to reduce the incidence of AL, (J&J). MATERIALS AND METHODS: This study included a total of 248 rectal tumor patients who underwent double stapler technique (DST) anastomotic procedures in the department of gastroenterological surgery /pediatric surgery at Gifu University School of Medicine from January 2017 to December 2021. The experience of a single institution utilizing the The Echelon circular™ stapler (ECP stapler:Manual VS Automatic) in rectal surgery cases was evaluated retrospectively from maintained database.

RESULT

One hundred thirty-nine patients (58.4%) were performed by manual circular stapling, 99 patients (41.6%) by powerd circular stapling. Diverting stoma was performed in 45 cases (32.4%) by manual circular stapling, 42 patients (42.4%) by powerd circular stapling Postoperative complications were occurred clavien-dindo grade II or higher in 57 cases (23.9%) and grade III or higher in 20 cases (8.4%). Anastomotic leakage occurred in 14 patients (5.9%) within all grades. After IPTW, the variables of patient characteristics was SMD ≤ 0.2 (Table.3), and there was a significant difference in anastomotic leakage (Odds Ratio (OR), 0.57; 95% Confidence Interval(CI), 0.34-0.98; p = 0.041). In addition, there was no significant difference in postoperative complications in grade II or higher (OR, 0.88; 95%CI, 0.65-1.19; p = 0.417) and grade III or higher (OR, 0.46; 95%CI, 0.29-0.74; p = 0.001) were significantly remarkable lower in powered circular stapling group.

CONCLUSION

In this IPTW comparison of patients undergoing rectal reconstructions, the ECP trial cohort had lower risks of several surgical complications AL and statistically signifcant lower rates of ileus/bowel obstruction, infection, and bleeding as Clavien-Dindo ≥ grade II and III as compared with for whom manual circular staplers were used.

Blood Perfusion Assessment by Indocyanine Green Fluorescence Imaging for Minimally Invasive Rectal Cancer Surgery (EssentiAL trial): A Randomized Clinical Trial

OBJECTIVE

The aim of the present randomized controlled trial was to evaluate the superiority of indocyanine green fluorescence imaging (ICG-FI) in reducing the rate of anastomotic leakage in minimally invasive rectal cancer surgery.

BACKGROUND

The role of ICG-FI in anastomotic leakage in minimally invasive rectal cancer surgery is controversial according to the published literature.

METHODS

This randomized, open-label, phase 3, trial was performed at 41 hospitals in Japan. Patients with clinically stage 0-III rectal carcinoma less than 12 cm from the anal verge, scheduled for minimally invasive sphincter-preserving surgery were preoperatively randomly assigned to receive a blood flow evaluation by ICG-FI (ICG+ group) or no blood flow evaluation by ICG-FI (ICG- group). The primary endpoint was the anastomotic leakage rate (grade A+B+C, expected reduction rate of 6%) analyzed in the modified intention-to-treat population.

RESULTS

Between December 2018 and February 2021, a total of 850 patients were enrolled and randomized. After the exclusion of 11 patients, 839 were subject to the modified intention-to-treat population (422 in the ICG+ group and 417 in the ICG- group). The rate of anastomotic leakage (grade A+B+C) was significantly lower in the ICG+ group (7.6%) than in the ICG- group (11.8%) (relative risk, 0.645; 95% confidence interval 0.422-0.987; P =0.041). The rate of anastomotic leakage (grade B+C) was 4.7% in the ICG+ group and 8.2% in the ICG- group ( P =0.044), and the respective reoperation rates were 0.5% and 2.4% ( P =0.021).

CONCLUSIONS

Although the actual reduction rate of anastomotic leakage in the ICG+ group was lower than the expected reduction rate and ICG-FI was not superior to white light, ICG-FI significantly reduced the anastomotic leakage rate by 4.2%.

Usefulness of blood flow evaluation by indocyanine green fluorescence in laparoscopic or robot-assisted surgery for colorectal cancer with persistent descending mesocolon

A persistent descending mesocolon is defined as a congenital fixation anomaly caused by the defective membrane fusion of the descending colon and the lateral abdominal wall. Anatomically, in persistent descending mesocolon, the left colonic artery is often shortened, and joins the marginal artery soon after its bifurcation from the inferior mesenteric artery, while the colonic mesentery often adheres firmly to the mesentery of the small intestine. As a result of these characteristics, anatomical knowledge of the persistent descending mesocolon and preservation of bowel blood flow are important during surgery for left-sided colorectal cancer to avoid adverse events. Moreover, indocyanine green based blood flow assessment is useful for the detailed evaluation of bowel ischemia at the anastomotic site. Here we report the usefulness of blood flow evaluation using indocyanine green fluorescence in laparoscopic or robot-assisted surgery for three patients with colorectal cancer and persistent descending mesocolons.

Evaluating Performance of Circular Staplers Using Comparative Test Methods for Evidence-Based Surgery

BACKGROUND

Circular stapler anastomosis is a common surgical procedure. Despite technological advancements, anastomotic leak remains a postoperative concern. Assessment of new technologies is impeded by variations in test methods and analysis, precluding outcome reproducibility and direct comparisons of results across studies. The development of robust and reproducible preclinical test methods is critical to accelerating stapling technology advancements.

METHODOLOGY

Leak pressure, staple line perfusion and security, and device removal force were quantified for triple-row (Tri-staple EEA, TriEEA) and double-row staplers (Echelon Circular Powered, ECP). Leak and perfusion testing were performed in vivo. Device removal force and staple line security testing were performed with synthetic medium using an Instron. Data were analyzed using unpaired student's t-test or Kruskal-Wallis test, with statistical significance defined as P < .05.

RESULTS

Leak pressure was 73% higher in TriEEA vs ECP (P = .016). TriEEA staple line failure force was lower than ECP at 40 and 50 mmHg (P = .001 and P = .023, respectively). Perfusion to the staple line was higher (148%) for TriEEA than for ECP (P = .003) and the force required to remove the device from its stapled anastomosis was 78% lower for TriEEA than for ECP (P < .001).

DISCUSSION/CONCLUSIONS

This report addresses a primary limitation in stapling research by presenting novel methodologies which enhance clinical relevance and provide sufficient detail for reproduction by independent investigators. These methods are applied to a comparison between triple-row and double-row staplers to demonstrate utility of new test methods in assessing key technology design features.

Time required for indocyanine green fluorescence emission for evaluating bowel perfusion in left-sided colon and rectal cancer surgery

BACKGROUND

Indocyanine green fluorescence imaging (ICG-FI) has been reported to be useful in reducing the incidence of anastomotic leakage (AL) in colectomy. This study aimed to investigate the correlation between the required time for ICG fluorescence emission and AL in left-sided colon and rectal cancer surgery using the double-stapling technique (DST) anastomosis.

METHODS

This retrospective study included 217 patients with colorectal cancer who underwent left-sided colon and rectal surgery using ICG-FI-based perfusion assessment at our department between November 2018 and July 2022. We recorded the time required to achieve maximum fluorescence emission after ICG systemic injection and assessed its correlation with the occurrence of AL.

RESULTS

Among 217 patients, AL occurred in 21 patients (9.7%). The median time from ICG administration to maximum fluorescence emission was 32 s (range 25-58 s) in the AL group and 28 s (range 10-45 s) in the non-AL group (p < 0.001). The cut-off value for the presence of AL obtained from the ROC curve was 31 s. In 58 patients with a required time for ICG fluorescence of 31 s or longer, the following risk factors for AL were identified: low preoperative albumin [3.4 mg/dl (range 2.6-4.4) vs. 3.9 mg/dl (range 2.6-4.9), p = 0.016], absence of preoperative mechanical bowel preparation (53.8% vs. 91.1%, p = 0.005), obstructive tumor (61.5% vs. 17.8%, p = 0.004), and larger tumor diameter [65 mm (range 40-90) vs. 35 mm (range 4.0-100), p < 0.001].

CONCLUSION

The time required for ICG fluorescence emission was associated with AL.

Lymphatic flow mapping during colon cancer surgery using indocyanine green fluorescence imaging

With the development of surgical technology, indocyanine green (ICG) fluorescence navigation systems may be useful in various areas of colorectal surgery, including tumor location confirmation, bowel perfusion, ureter identification, and lymph node mapping. This review provides an overview of the current status of ICG-based navigation surgery in colorectal surgery, emphasizing its role in lymphatic flow mapping. This state-of-the-art approach will allow for appropriate oncological surgeries in the field of colorectal cancer and improve the patient's prognosis.

Intraoperative bowel perfusion assessment methods and their effects on anastomotic leak rates: meta-analysis

BACKGROUND

Anastomotic leak is one of the most feared complications of colorectal surgery, and probably linked to poor blood supply to the anastomotic site. Several technologies have been described for intraoperative assessment of bowel perfusion. This systematic review and meta-analysis aimed to evaluate the most frequently used bowel perfusion assessment modalities in elective colorectal procedures, and to assess their associated risk of anastomotic leak. Technologies included indocyanine green fluorescence angiography, diffuse reflectance spectroscopy, laser speckle contrast imaging, and hyperspectral imaging.

METHODS

The review was preregistered with PROSPERO (CRD42021297299). A comprehensive literature search was performed using Embase, MEDLINE, Cochrane Library, Scopus, and Web of Science. The final search was undertaken on 29 July 2022. Data were extracted by two reviewers and the MINORS criteria were applied to assess the risk of bias.

RESULTS

Some 66 eligible studies involving 11 560 participants were included. Indocyanine green fluorescence angiography was most used with 10 789 participants, followed by diffuse reflectance spectroscopy with 321, hyperspectral imaging with 265, and laser speckle contrast imaging with 185. In the meta-analysis, the total pooled effect of an intervention on anastomotic leak was 0.05 (95 per cent c.i. 0.04 to 0.07) in comparison with 0.10 (0.08 to 0.12) without. Use of indocyanine green fluorescence angiography, hyperspectral imaging, or laser speckle contrast imaging was associated with a significant reduction in anastomotic leak.

CONCLUSION

Bowel perfusion assessment reduced the incidence of anastomotic leak, with intraoperative indocyanine green fluorescence angiography, hyperspectral imaging, and laser speckle contrast imaging all demonstrating comparable results.

Modified pull-through coloanal anastomosis to avoid permanent stomas and reduce postoperative complications for lower rectal tumors

BACKGROUND

We performed pull-through hand-sewn coloanal anastomosis immediately after sphincter-preserving ultralow anterior resection (ULAR) [pull-through ultra (PTU)] to avoid permanent stoma and reduce postoperative complications of lower rectal tumors. This study aimed to compare the clinical outcomes of PTU versus non-PTU (stapled or hand-sewn coloanal anastomosis with diverting stoma) after sphincter-preserving ULAR for lower rectal tumors.

METHODS

This retrospective cohort study analyzed prospectively maintained data from 100 consecutive patients who underwent PTU (n = 29) or non-PTU (n = 71) after sphincter-preserving ULAR for rectal tumors between January 2011 and March 2023. In PTU, hand-sewn coloanal anastomosis was immediately performed using 16 stitches of 4-0 monofilament suture during primary surgery. The clinical outcomes were assessed. The primary outcomes were rates of permanent stomas and overall postoperative complications.

RESULTS

The PTU group was significantly less likely to require a permanent stoma than the non-PTU group (P < 0.01). None of the patients in the PTU group required permanent stoma and the rate of overall complications was significantly lower in the PTU group (P = 0.01). The median operative time was comparable between the two groups (P = 0.33) but the median operative time during the second stage was significantly shorter in the PTU group (P < 0.01). The rates of anastomotic leakage and complications of Clavien-Dindo grade III were comparable between the two groups. Diverting ileostomy was performed in two patients with an anastomotic leak in the PTU group. The PTU group was significantly less likely to require a diverting ileostomy than those in the non-PTU group (P < 0.01). The composite length of hospital stay was significantly shorter in the PTU group (P < 0.01).

CONCLUSIONS

PTU via immediate coloanal anastomosis for lower rectal tumors is a safe alternative to the current sphincter-preserving ULAR with diverting ileostomy for patients who wish to avoid a stoma.

Impact of a circular powered stapler on preventing anastomotic leakage in patients with left-sided colorectal cancer: a retrospective study

BACKGROUND

The powered circular stapler, which was developed with the aim of providing reliable and reproducible anastomosis, provides complete anastomosis, resulting in a reduced risk of anastomotic leakage. The aim of this study was to compare the incidence of anastomotic leakage between a conventional manual circular stapler (MCS) and the ECHELON CIRCULAR™ Powered Stapler (ECPS) in patients with left-sided colorectal cancer who underwent anastomosis with the double stapling technique.

METHODS

A total of 187 patients with left-sided colorectal cancer who underwent anastomosis with the double stapling technique with a conventional MCS or the ECPS during surgery at Osaka City University Hospital between January 2016 and July 2022 were enrolled in this study.

RESULTS

The incidence of anastomotic leakage in the ECPS group was significantly lower than that in the MCS group (4.4% versus 14.3%, p = 0.048). Furthermore, even after propensity score matching, an association was found between the use of the ECPS and a reduced incidence of anastomotic leakage.

CONCLUSION

The ECPS has the potential to help reduce the rate of anastomotic leakage in left-sided colorectal surgery.

Fluorescent Imaging in Visceral Surgery: Current Opportunities and Future Perspectives

Background

Fluorescent imaging using indocyanine green (FI-ICG) has become quite popular in the past century, giving the surgeon various pre- and intraoperative approaches in visceral surgery. Nevertheless, several aspects and pitfalls of using the technology need to be addressed.

Summary

This article focused on the applications of FI-ICG in esophageal and colorectal surgery as this is where the clinical relevance is most important. Important benchmark studies were summarized to explain the background. In addition, dosage, the timing of application, and future perspectives - especially quantification methods - were the article's content.

Key Message

There are currently encouraging data on the use of FI-ICG, particularly concerning perfusion assessment to reduce anastomotic leakage, although its use is mainly subjective. The optimal dosage remains unclear; for perfusion evaluation, it should be around 0.1 mg/kg body weight. Moreover, the quantification of FI-ICG opens new possibilities, so that reference values may be available in the future. However, in addition to perfusion measurement, the detection of additional hepatic lesions such as liver metastases or lesions of peritoneal carcinomatosis is also possible. A standardization of FI-ICG and further studies are needed to fully utilize FI-ICG.

Efficacy of the polyglycolic acid sheet for preventing anastomotic leakage in double-stapling technique anastomosis for left-sided colon or rectal cancer surgery: a propensity score-matched study

BACKGROUND

To prevent anastomotic leakage in patients with left-sided colorectal cancer who underwent double-stapling technique (DST) anastomosis, we investigated a new method: DST anastomosis with a polyglycolic acid (PGA) sheet. This procedure has been shown to have the potential to decrease the rate of anastomotic leakage. However, due to the small number of cases enrolled in our previous study, it was not possible to compare the outcomes of the new and conventional procedures. The aim of this study was to evaluate the effect of the PGA sheet on preventing anastomotic leakage in patients with left-sided colorectal cancer who underwent DST anastomosis by retrospectively comparing the anastomotic leakage rate between the PGA sheet and conventional groups.

METHODS

A total of 356 patients with left-sided colorectal cancer who underwent DST anastomosis during surgery at Osaka City University Hospital between January 2016 and April 2022 were enrolled in this study. Propensity score matching was performed to reduce the confounding effects secondary to imbalances in the use of PGA sheets.

RESULTS

The PGA sheet was used in 43 cases (PGA sheet group) and it was not used in 313 cases (conventional group). After propensity score matching, the incidence of anastomotic leakage in the PGA sheet group was significantly lower than that in the conventional group.

CONCLUSION

DST anastomosis with PGA sheet, which is easy to perform, contributes to the reduction of anastomotic leakage rate by increasing the strength of the anastomotic site.

Effectiveness of fluorescence-guided methods using near-infrared fluorescent clips of robotic colorectal surgery: a case report

BACKGROUND

This is the first report on the application of the Da Vinci-compatible near-infrared fluorescent clips (NIRFCs) as tumor markers to localize colorectal cancer lesions during robotic surgery. In laparoscopic and robotic colorectal surgeries, the accuracy of tumor marking is a critical issue that remains unresolved. This study aimed to determine the accuracy of NIRFCs in localizing tumors for intestinal resection. Indocyanine green (ICG) was also used to verify the feasibility of safely performing an anastomosis.

CASE PRESENTATION

A patient diagnosed with rectal cancer was scheduled to undergo a robot-assisted high anterior resection. During colonoscopy 1 day prior to the surgery, four Da Vinci-compatible NIRFCs were placed intraluminally 90° around the lesion. The locations of the Da Vinci-compatible NIRFCs were confirmed using firefly technology, and ICG staining was performed before cutting the oral side of the tumor. The locations of the Da Vinci-compatible NIRFCs and the intestinal resection line were confirmed. Moreover, sufficient margins were obtained.

CONCLUSIONS

In robotic colorectal surgery, fluorescence guidance with firefly technology offers two advantages. First, it has an oncological advantage, because marking with the Da Vinci-compatible NIRFCs allows for real-time monitoring of the lesion location. This enables sufficient intestinal resection by grasping the lesion precisely. Second, it reduces the risk of postoperative complications, because ICG evaluation with firefly technology prevents postoperative anastomotic leakage. Fluorescence guidance in robot-assisted surgery is useful. In the future, the application of this technique should be evaluated for lower rectal cancer.

Indocyanine green fluorescence angiography decreases the risk of anastomotic leakage after rectal cancer surgery: a systematic review and meta-analysis

Background

Anastomotic leakage is a serious complication after rectal cancer resection. Intraoperative use of indocyanine green fluorescence angiography (ICGFA) can help prevent anastomotic leakage, but its use is controversial. We conducted a systematic review and meta-analysis to determine the efficacy of ICGFA in reducing anastomotic leakage.

Methods

Relevant data and research published until September 30, 2022, was retrieved from the PubMed, Embase, and Cochrane Library databases, and the difference in the incidence of anastomotic leakage after rectal cancer resection between ICGFA and standard treatment was compared.

Results

This meta-analysis included 22 studies with a total of 4,738 patients. The results showed that ICGFA use during surgery decreased the incidence of anastomotic leakage after rectal cancer surgery [risk ratio (RR) = 0.46; 95% confidence interval (95% CI), 0.39-0.56; p < 0.001]. Simultaneously, in subgroup analyses for different regions, ICGFA was found to be used to reduce the incidence of anastomotic leakage after rectal cancer surgery in Asia (RR = 0.33; 95% CI, 0.23-0.48; p < 0.00001) and Europe (RR = 0.38; 95% CI, 0.27-0.53; p < 0.00001) but not in North America (RR = 0.72; 95% CI, 0.40-1.29; p = 0.27). Regarding different levels of anastomotic leakage, ICGFA reduced the incidence of postoperative type A anastomotic leakage (RR = 0.25; 95% CI, 0.14-0.44; p < 0.00001) but did not reduce the incidence of type B (RR = 0.70; 95% CI, 0.38-1.31; p = 0.27) and type C (RR = 0.97; 95% CI, 0.51-1.97; p = 0.93) anastomotic leakages.

Conclusion

ICGFA has been linked to a reduction in anastomotic leakage after rectal cancer resection. However, multicenter randomized controlled trials with larger sample sizes are required for further validation.

Predictive Factors for Anastomotic Leakage Following Colorectal Cancer Surgery: Where Are We and Where Are We Going?

Anastomotic leakage (AL) remains one of the most severe complications following colorectal cancer (CRC) surgery. Indeed, leaks that may occur after any type of intestinal anastomosis are commonly associated with a higher reoperation rate and an increased risk of postoperative morbidity and mortality. At first, our review aims to identify specific preoperative, intraoperative and perioperative factors that eventually lead to the development of anastomotic dehiscence based on the current literature. We will also investigate the role of several biomarkers in predicting the presence of ALs following colorectal surgery. Despite significant improvements in perioperative care, advances in surgical techniques, and a high index of suspicion of this complication, the incidence of AL remained stable during the last decades. Thus, gaining a better knowledge of the risk factors that influence the AL rates may help identify high-risk surgical patients requiring more intensive perioperative surveillance. Furthermore, prompt diagnosis of this severe complication may help improve patient survival. To date, several studies have identified predictive biomarkers of ALs, which are most commonly associated with the inflammatory response to colorectal surgery. Interestingly, early diagnosis and evaluation of the severity of this complication may offer a significant opportunity to guide clinical judgement and decision-making.

Essential updates 2020/2021: Advancing precision medicine for comprehensive rectal cancer treatment

In the paradigm shift related to rectal cancer treatment, we have to understand a variety of new emerging topics to provide appropriate treatment for individual patients as precision medicine. However, information on surgery, genomic medicine, and pharmacotherapy is highly specialized and subdivided, creating a barrier to achieving thorough knowledge. In this review, we summarize the perspective for rectal cancer treatment and management from the current standard-of-care to the latest findings to help optimize treatment strategy.

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.

Early and late anastomotic leak after colorectal surgery: A systematic review of the literature

The aim of this study was to review and to assess the quality of the scientific articles regarding early and late anastomotic leak (AL) after colorectal surgery and their risk factors. An electronic systematic search for articles on Colorectal Surgery, AL and its timing was undertaken using the MEDLINE database via PubMed, Cochrane and Embase. The selected articles were thoroughly reviewed and assessed for methodological quality using a validated methodology quality score (MINCIR score). This review was registered in the PROSPERO registry under ID: CRD42022303012. 9 articles were finally reviewed in relation to the topic of early and late anastomotic leak. There is a lack of consensus regarding the exact cut-off in time to define early and late anastomotic leak, but it is clear that they are two differentiated entities. The first, occurring in relation to technical factors; whereas the latter, is related to impaired healing.

[Fluorescence angiography in colorectal surgery]

OBJECTIVE

To evaluate the impact of indocyanine green fluorescence angiography on the incidence of colorectal anastomotic leakage.

MATERIAL AND METHODS

We summarized the results of non-comparative and randomized clinical trials, as well as meta-analyses.

RESULTS

Indocyanine green fluorescence angiography changes the anastomosis site in 10% of patients due to inadequate blood supply to intestinal wall at the initially scheduled level. This method can decrease the incidence of «low» colorectal anastomosis leakage.

CONCLUSION

Routine intraoperative fluorescence angiography with indocyanine green can become a standard method for prevention of colorectal anastomotic leakage.

Indocyanine green fluorescence imaging during laparoscopic rectal cancer surgery could reduce the incidence of anastomotic leakage: a single institutional retrospective cohort study

BACKGROUND

There is insufficient evidence on whether indocyanine green (ICG) fluorescence angiography can reduce the incidence of anastomotic leakage (AL). This retrospective cohort study aimed to evaluate the effect of ICG fluorescence angiography on AL rates in laparoscopic rectal cancer surgery at a single institution.

METHODS

Patients who underwent laparoscopic low anterior resection or intersphincteric resection with ICG fluorescence angiography (ICG group; n = 73) and patients who underwent a similar surgical procedure for rectal cancer without ICG fluorescence (non-ICG group; n = 114) were enrolled consecutively in this study. ICG fluorescence angiography was performed prior to transection of the proximal colon, and anastomosis was performed with sufficient perfusion using ICG fluorescence imaging. AL incidence was compared between both groups, and the risk factors for AL were analyzed.

RESULTS

AL occurred in 3 (4.1%) and 14 (12.3%) patients in the ICG and non-ICG groups, respectively. In the ICG group, the median perfusion time from ICG injection was 34 s, and 5 patients (6.8%) required revision of the proximal transection line. None of the patients requiring revision of the proximal transection line developed AL. In univariate analysis, longer operating time (odds ratio: 2.758; 95% confidence interval: 1.023-7.624) and no implementation of ICG fluorescence angiography (odds ratio: 3.266; 95% confidence interval: 1.038-11.793) were significant factors associated with AL incidence, although the creation of a diverting stoma or insertion of a transanal tube was insignificant.

CONCLUSION

ICG fluorescence angiography was associated with a significant reduction in AL during laparoscopic rectal cancer surgery. Changes in the surgical plan due to ICG fluorescence visibility may help improve the short-term outcomes of patients with rectal cancer.

Use of fluorescence imaging and indocyanine green during colorectal surgery: Results of an intercontinental Delphi survey

BACKGROUND

Fluorescence imaging with indocyanine green is increasingly being used in colorectal surgery to assess anastomotic perfusion, and to detect sentinel lymph nodes.

METHODS

In this 2-round, online, Delphi survey, 35 international experts were asked to vote on 69 statements pertaining to patient preparation and contraindications to fluorescence imaging during colorectal surgery, indications, technical aspects, potential advantages/disadvantages, and effectiveness versus limitations, and training and research. Methodological steps were adopted during survey design to minimize risk of bias.

RESULTS

More than 70% consensus was reached on 60 of 69 statements, including moderate-strong consensus regarding fluorescence imaging's value assessing anastomotic perfusion and leak risk, but not on its value mapping sentinel nodes. Similarly, although consensus was reached regarding most technical aspects of its use assessing anastomoses, little consensus was achieved for lymph-node assessments. Evaluating anastomoses, experts agreed that the optimum total indocyanine green dose and timing are 5 to 10 mg and 30 to 60 seconds pre-evaluation, indocyanine green should be dosed milligram/kilogram, lines should be flushed with saline, and indocyanine green can be readministered if bright perfusion is not achieved, although how long surgeons should wait remains unknown. The only consensus achieved for lymph-node assessments was that 2 to 4 injection points are needed. Ninety-six percent and 100% consensus were reached that fluorescence imaging will increase in practice and research over the next decade, respectively.

CONCLUSION

Although further research remains necessary, fluorescence imaging appears to have value assessing anastomotic perfusion, but its value for lymph-node mapping remains questionable.

Cost analysis of indocyanine green fluorescence angiography for prevention of anastomotic leakage in colorectal surgery

BACKGROUND

Indocyanine green, near infrared, fluorescence angiography (ICG-FA) is increasingly adopted in colorectal surgery for intraoperative tissue perfusion assessment to reduce anastomotic leakage rates. However, the economic impact of this intervention has not been investigated. This study is a cost analysis of the routine use of ICG-FA in colorectal surgery from the hospital payer perspective.

METHODS

A decision analysis model was developed for colorectal resections considering two scenarios: resection without using ICG-FA and resection with intraoperative ICG-FA for anastomotic perfusion assessment. Incorporated into the model were the costs of ICG agent, fluorescence angiography equipment, surgery, anastomotic leak, and the leak rates with and without ICG-FA. All input data were derived from recent publications.

RESULTS

The routine use of ICG-FA for colorectal anastomosis is cost saving when cost analysis is performed using the following base case assumptions: 8.6% leak rate without ICG-FA, odds ratio of 0.46 for reduction of leakage with ICG-FA (4.8% leak rate relative to 8.6% base case), cost of ICG-FA of $250, and incremental cost of leak, not requiring reoperation, of $9,934.50. In one-way sensitivity analyses, routine use of ICG-FA was cost saving if the cost of an anastomotic leak is more than $5616.29, the cost of ICG-FA is less than $634.44, the leak rate (without ICG-FA) is higher than 4.9%, or the odds ratio for reduction of leak with ICG-FA is less than 0.69. There is a per-case saving of $192.22 with the use of ICG-FA.

CONCLUSION

Using the best available evidence and most conservative base case values, routine use of ICG-FA in colorectal surgery was found to be cost saving. Since the evidence suggests there is a reduction in leak rate, the routine use of ICG-FA is a dominating strategy. However, the overall quality of evidence is low and there is a clear need for prospective, randomized controlled trials.

Short-term outcomes of robot-assisted versus conventional laparoscopic surgery for mid and low rectal cancer after neoadjuvant chemoradiotherapy: a propensity score-matched analysis

The benefits of robot-assisted laparoscopic surgery (RALS) for rectal cancer remain controversial. Only a few studies have evaluated the safety and feasibility of RALS following neoadjuvant chemoradiotherapy (NCRT). This study aimed to compare the short-term outcomes of RALS versus conventional laparoscopic surgery (CLS) after NCRT for rectal cancer. Propensity score matching of 111 consecutive patients who underwent RALS or CLS after NCRT for rectal adenocarcinoma between February 2014 and February 2022 was performed. Among them, 60 matched patients were enrolled and their short-term outcomes were compared. Although operative time, conversion rate to open laparotomy and blood loss were comparable, the incidence of postoperative complications, including anastomotic leakage, was significantly lower, urinary retention tended to be lower, and the days to soft diet intake and postoperative hospital stay were significantly shorter in the RALS than the CLS group. No postoperative mortality was observed in either group, and there were no significant differences in terms of resection margins and number of lymph nodes dissected. RALS after NCRT for rectal cancer is safe and technically feasible, and has acceptable short-term outcomes. Further studies are required for validation of the long-term oncological outcomes.

A Narrative Review of the Usefulness of Indocyanine Green Fluorescence Angiography for Perfusion Assessment in Colorectal Surgery

Anastomotic leakage is one of the most dreaded complications of colorectal surgery and is strongly associated with tissue perfusion. Indocyanine green fluorescence angiography (ICG-FA) using indocyanine green and near-infrared systems is an innovative technique that allows the visualization of anastomotic perfusion. Based on this information on tissue perfusion status, surgeons will be able to clearly identify colorectal segments with good blood flow for safer colorectal anastomosis. The results of several clinical trials indicate that ICG-FA may reduce the risk of AL in colorectal resection; however, the level of evidence is not high, as several other studies have failed to demonstrate a reduction in the risk of AL. Several large-scale RCTs are currently underway, and their results will determine whether ICG-FA is, indeed, useful. The major limitation of the current ICG-FA evaluation method, however, is that it is subjective and based on visual assessment by the surgeon. To complement this, the utility of objective evaluation methods for fluorescence using quantitative parameters is being investigated. Promising results have been reported from several clinical trials, but all trials are preliminary owing to their small sample size and lack of standardized protocols for quantitative evaluation. Therefore, appropriately standardized, high-quality, large-scale studies are warranted.