Indocyanine green-enhanced fluorangiography (ICGf) in laparoscopic extraperitoneal rectal cancer resection

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.

Intraoperative left-sided colorectal anastomotic testing in clinical practice: a multi-treatment machine-learning analysis of the iCral3 prospective cohort

BACKGROUND

Current evidence about intraoperative anastomotic testing after left-sided colorectal resections is still controversial. The aim of this study was to analyze the impact of Indocyanine Green fluorescent angiography (ICG-FA) and air-leak test (ALT) over standard assessment on anastomotic leakage (AL) rates according to surgeon's perception of anastomosis perfusion and/or integrity in clinical practice.

METHODS

A database of 2061 patients who underwent left-sided colorectal resections was selected from patients enrolled in a prospective multicenter study. It was retrospectively analyzed through a multi-treatment machine-learning model considering standard visual assessment (NW; No. = 899; 43.6%) as the reference treatment arm, compared to ICG-FA alone (WP; No. = 409; 19.8%), ALT alone (WI; No. = 420; 20.4%) or both (WPI; No. = 333; 16.2%). Twenty-four covariates potentially affecting the outcomes were included and balanced into the model within the subgroups. The primary endpoint was AL, the secondary endpoints were overall morbidity (OM), major morbidity (MM), reoperation for AL, and mortality. All the results were reported as odds ratio (OR) with 95% confidence intervals (95%CI).

RESULTS

The WPI subgroup showed significantly higher AL risk (OR 1.91; 95% CI 1.02-3.59; p 0.043), MM risk (OR 2.35; 95% CI 1.39-3.97; p 0.001), and reoperation for AL risk (OR 2.44; 95% CI 1.12-5.31; p 0.025). No other significant differences were recorded.

CONCLUSIONS

This study showed that the surgeons' perception of both anastomotic perfusion and integrity (WPI subgroup) was associated to a significantly higher risk of AL and related morbidity, notwithstanding the extensive use of both ICG-FA and ALT testing.

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.

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.

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.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Indocyanine Green Fluorescence Guided Surgery in Colorectal Surgery

BACKGROUND

Indocyanine green (ICG) imaging has been increasingly used for intraoperative guidance in colorectal surgery over the past decade. The aim of this study was to review and organize, according to different type of use, all available literature on ICG guided colorectal surgery and highlight areas in need of further research and discuss future perspectives.

METHODS

PubMed, Scopus, and Google Scholar databases were searched systematically through November 2022 for all available studies on fluorescence-guided surgery in colorectal surgery.

RESULTS

Available studies described ICG use in colorectal surgery for perfusion assessment, ureteral and urethral assessment, lymphatic mapping, and hepatic and peritoneal metastases assessment. Although the level of evidence is low, results are promising, especially in the role of ICG in reducing anastomotic leaks.

CONCLUSIONS

ICG imaging is a safe and relatively cheap imaging modality in colorectal surgery, especially for perfusion assessment. Work is underway regarding its use in lymphatic mapping, ureter identification, and the assessment of intraperitoneal metastatic disease.

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.

Meta analysis of indocyanine green fluorescence in patients undergoing laparoscopic colorectal cancer surgery

This meta-analysis intended to systematically evaluate the clinical implications of indocyanine green fluorescence (ICG) in patients undergoing laparoscopic colorectal surgery. PubMed, MEDLINE, Cochrane Library, EMBASE, China National Knowledge Infrastructure (CNKI), Wanfang Database, VIP Medical Information System and China Biomedical Database were synthetically searched for studies published from inception to April 14, 2022. The randomized controlled trials comparing ICG-use with controls were selected. The incidence of anastomotic leakage (AL), lymph node detection, operation duration, intraoperative bleeding, postoperative morbidity, and hospitalization time were evaluated in summary analysis, and calculated the corresponding 95% confidence intervals (CI). Subsequently, in addition to subgroup analyses, studies for heterogeneity, sensitivity, and publication bias were carried out. Consequently, 3453 patients in the enrolled 15 studies were included; 1616 patients were allocated to the experimental group, and 1837 patients were assigned to the control group. The ICG group had a significantly decreased risk of AL (RR: 0.50, 95% CI: 0.37-0.67) and shorter hospitalization time (SMD: -0.31, 95% CI: -0.54-0.08) compared to the control group. Meanwhile, the ICG showed clearly better lymph node detection (SMD: 0.19, 95% CI: 0.02-0.36). However, when the content of operation duration (SMD: -0.07, 95% CI: -0.30-0.15) and intraoperative bleeding (SMD: -0.16, 95% CI: -0.35-0.04) were compared, no statistical significance was found. Furthermore, the pooled analysis of postoperative morbidity was not statistically significant (RR:0.79, 95% CI: 0.58-1.08). The results of the subgroup analysis of AL indicated that there may be regional variations in AL (RR: 0.50, 95% CI: 0.37-0.67) but not in postoperative morbidity (RR: 0.79, 95% CI: 0.58-1.08). In conclusion, the application of ICG in laparoscopic colorectal surgery can effectively reduce the AL, lymph node detection, and hospitalization time. However, more multicenter large-sample randomized controlled trials are required to further confirm its advantages. The meta-analysis was registered in PROSPERO (no. CRD42022288054).

Safety and Efficacy of Indocyanine Green in Colorectal Cancer Surgery: A Systematic Review and Meta-Analysis of 11,047 Patients

Despite the technological advances and improved surgical skills, the incidence of anastomotic leakage following colorectal cancer surgery still ranges from 4% to 19%. Therefore, we performed a systematic review and meta-analysis to evaluate the efficacy and safety of indocyanine green (ICG) use in colorectal cancer surgery. An online search of the Embase, MEDLINE, and Cochrane Central Register of Controlled Trials (CENTRAL) databases (from inception to 10 November 2021) was performed, in addition to manual screening. Thirty-two studies involving 11,047 patients were considered eligible for the meta-analysis. The anastomotic leak rate in the ICG and non-ICG groups varied and amounted to 3.7% vs. 7.6%, respectively (RR = 0.46; 95% CI: 0.39-0.56; p < 0.001). The rate in randomized controlled trials (RCTs) was 8.1% in the ICG group compared with 12.1% in the non-ICG group (RR = 0.67; 95% CI: 0.46-0.98; p = 0.04). In non-RCTs, it equaled 3.1% vs. 7.3%, respectively (RR = 0.43; 95% CI: 0.35-0.52; p < 0.001). Although the publications encompassed in our meta-analysis present different patients, with different factors influencing the results, a pooled analysis revealed a lower incidence of anastomotic leak in cases with ICG use. There are several other convincing advantages: safety, simplicity, and short time of the method adjustment. The presented meta-analysis indicates ICG perfusion assessment as a tool worth considering to decrease the rate of complications following colorectal surgery-valuable in the context of other, well-known risk factors.

Impact of change in the surgical plan based on indocyanine green fluorescence angiography on the rates of colorectal anastomotic leak: a systematic review and meta-analysis

BACKGROUND

In the present study, patients with colorectal anastomoses that were assessed with indocyanine green (ICG) fluorescence angiography (FA) were compared to patients who had only white light visual inspection of their anastomosis. The impact of change in surgical plan guided by ICG-FA on anastomotic leak (AL) rates was assessed.

METHODS

PubMed, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials were queried for eligible studies. Studies included were comparative cohort studies and randomized trials that compared perfusion assessment of colorectal anastomosis with ICG-FA and inspection under white light. Main outcome measures were change in surgical plan guided by ICG-FA and rates of AL. Risk of bias was assessed using RoB-2 and ROBINS-1 tools. Differences between the two groups in categorical and continuous variables were expressed as odds ratio (OR) with 95% confidence interval (CI) and weighted mean difference.

RESULTS

This systematic review included 27 studies comprising 8786 patients (48.5% males). Using ICG-FA was associated with significantly lower odds of AL (OR 0.452; 95% CI 0.366-0.558) and complications (OR 0.747; 95% CI 0.592-0.943) than the control group. The weighted mean rate of change in surgical plan based on ICG-FA was 9.6% (95% CI 7.3-11.8) and varied from 0.64% to 28.75%. A change in surgical plan was associated with significantly higher odds of AL (OR 2.73; 95% CI 1.54-4.82).

LIMITATIONS

Technical heterogeneity due to using different dosage of ICG and statistical heterogeneity in operative time and complication rates.

CONCLUSION

Assessment of colorectal anastomoses with ICG-FA is likely to be associated with lower odds of anastomotic leak than is traditional white light assessment. Change in plan based on ICG-FA may be associated with higher odds of AL. PROSPERO registration number: CRD42021235644.

Predicting Clinical Outcomes in a Diabetic Foot Ulcer Population Using Fluorescence Imaging

OBJECTIVE

To retrospectively evaluate a cohort of patients with diabetic foot ulcers to determine if the rate of microcirculatory flow detected by fluorescence imaging within the wound and surrounding tissue is associated with healing outcomes.

METHODS

Tissue perfusion parameters used for the current analysis were the ingress rate (IR) within the wound bed (R01) and in an area remote from the wound (REF), as well as time to first blush. Wounds were then categorized based on their outcome (healed, healing, chronic nonhealing, partial foot amputation, proximal amputation below the knee) and compared between patients with positive or negative wound healing outcomes.

RESULTS

The final study cohort included 61 wounds and demonstrated that a higher IR within R01 and REF areas was significantly associated with positive outcomes, whereas time to first blush was not. A two-predictor logistic model found a significant relationship between IR (R01 and REF) and odds of wound healing.

CONCLUSIONS

Fluorescence imaging evaluation of a diabetic foot ulcer can provide valuable information on healing outcomes that can help determine if a wound is progressing toward healing and therefore may help inform the need for advanced wound modalities, referrals, and amputation.

Intraoperative use of indocyanine green fluorescence imaging in rectal cancer surgery: The state of the art

Indocyanine green (ICG) fluorescence imaging is widely used in abdominal surgery. The implementation of minimally invasive rectal surgery using new methods like robotics or a transanal approach required improvement of optical systems. In that setting, ICG fluorescence optimizes intraoperative vision of anatomical structures by improving blood and lymphatic flow. The purpose of this review was to summarize all potential applications of this upcoming technology in rectal cancer surgery. Each type of use has been separately addressed and the evidence was investigated. During rectal resection, ICG fluorescence angiography is mainly used to evaluate the perfusion of the colonic stump in order to reduce the risk of anastomotic leaks. In addition, ICG fluorescence imaging allows easy visualization of organs such as the ureter or urethra to protect them from injury. This intraoperative technology is a valuable tool for conducting lymph node dissection along the iliac lymphatic chain or to better identifying the rectal dissection planes when a transanal approach is performed. This is an overview of the applications of ICG fluorescence imaging in current surgical practice and a synthesis of the results obtained from the literature. Although further studies are need to investigate the real clinical benefits, these findings may enhance use of ICG fluorescence in current clinical practice and stimulate future research on new applications.

Clinical effect and standardization of indocyanine green angiography in the laparoscopic colorectal surgery

Anastomotic complications occur after 5% to 20% of operations for rectosigmoid colon cancer. The intestinal perfusion status at the anastomotic site is an important modifiable risk factor, and surgeons should carefully evaluate and optimize the perfusion at the intended site of anastomosis. Indocyanine green (ICG) angiography is a simple noninvasive perfusion assessment modality. The use of ICG angiography is rapidly spreading in the field of colorectal surgery. However, there is debate on its contribution to reducing anastomotic complications. In this review, we discuss the clinical utility and the standardization of ICG angiography. ICG angiography can unequivocally reveal unfavorable perfusion zones and provide quantitative parameters to predict the risk of hypoperfusion-related anastomotic complications. Many studies have demonstrated the clinical utility of ICG angiography for reducing anastomotic complications. Recently, two multicenter randomized clinical trials reported that ICG angiography did not significantly reduce the incidence of anastomotic leakage. Most previous studies have been small-scale single-center studies, and there is no standardized ICG angiography protocol to date. Additionally, ICG angiography evaluations have mostly relied on surgeons’ subjective judgment. For these reasons, it is necessary to establish a standardized ICG angiography protocol and develop a quantitative analysis protocol for the objective assessment. In conclusion, ICG angiography could be useful for detecting poorly perfused colorectal segments to prevent anastomotic leakage after colorectal surgery. An optimized and standardized ICG angiography protocol should be established to improve the reliability of perfusion assessments. In the future, artificial intelligence-based quantitative analyses could be used to easily assess colonic perfusion status.

Indocyanine green fluorescence angiography versus standard intraoperative methods for prevention of anastomotic leak in colorectal surgery: meta-analysis

BACKGROUND

Assessment of anastomotic blood perfusion with intraoperative indocyanine green fluorescence angiography (ICG-FA) may be effective in preventing anastomotic leak compared with standard intraoperative methods in colorectal surgery.

METHODS

MEDLINE, PubMed, Cochrane Central Register of Controlled Trials and the Cochrane Library were searched for RCTs and observational studies on intraoperative ICG-FA to May 2020. Odds ratios (ORs), risk differences and mean differences (MDs) were calculated with 95 per cent c.i. based on intention-to-treat analysis. The number needed to treat for an additional beneficial outcome was also estimated.

RESULTS

Twenty-five comparative studies included a total of 7735 patients. The use of intraoperative ICG fluorescence angiography was linked with a significant reduction in all grades anastomotic leak (OR 0.39 (95 per cent c.i. 0.31 to 0.49), P < 0.001; number needed to treat for an additional beneficial outcome (NNTB) 23) and length of hospital stay (MD -0.72 (95 per cent c.i. -1.22 to -0.21) days, P = 0.006). A significantly lower incidence of grade A (OR 0.33 (0.18 to 0.60), P < 0.001), grade B (OR 0.58 (0.35 to 0.97), P = 0.04) and grade C (OR 0.59 (0.38 to 0.92), P = 0.02) anastomotic leak was demonstrated in favour of ICG-FA. For low or ultra-low rectal resection, the odds of developing anastomotic leakage was 0.32 (0.23 to 0.45) (P < 0.001; NNTB 14). There were no differences in duration of surgery, and no adverse events related to ICG fluorescent injection.

CONCLUSION

The use of ICG-FA instead of standard intraoperative methods to assess anastomosis blood perfusion in colorectal surgery leads to a significant reduction in anastomotic leakage and in the need for surgical reintervention for anastomotic leak, especially in patients with low or ultra-low rectal resections.

Effect of indocyanine green fluorescence angiography on preventing anastomotic leakage after colorectal surgery: a meta-analysis

Anastomotic leakage (AL) is a serious but not uncommon complication after colorectal surgery. We conducted this study to evaluate the effect of routine indocyanine green fluorescence angiography (ICG-FA) on reducing the AL rate after colorectal surgery. We identified all research articles about colorectal surgery using ICG-FA, published in the PubMed, EMBASE, and Cochrane Library databases from the date of database establishment to May 2020. Revman 5.3 was used for statistical analysis. We analyzed 22 controlled studies and 7 non-controlled studies on ICG-FA, including 6312 patients. The controlled studies included 2354 patients in the ICG group and 3522 patients in the non-ICG group. Meta-analysis showed that ICG-FA reduced the AL rate after colorectal surgery significantly (RR = 0.39; 95% CI 0.30-0.50; P < 0.00001). However, patients whose resection line was changed based on the fluorescence angiography had a higher AL rate than those whose resection line was not changed (OR = 5.37; 95% CI 2.67-10.81; P < 0.00001). The overall complication rate, severe complication rate, and reoperation rate in the ICG group were significantly lower than those in the non-ICG group (RR = 0.79, 95% CI 0.67-0.92, P = 0.002; RR = 0.67, 95% CI 0.47-0.96, P = 0.03; RR = 0.53, 95% CI 0.29-0.96, P = 0.04, respectively), whereas the postoperative ileus rate was significantly higher in the ICG group than in the non-ICG group (RR = 1.65; 95% CI 1.09-2.50; P = 0.02), especially in Western countries (RR = 1.6; 95% CI 1.04-2.47; P = 0.03).ICG-FA may reduce the AL rate after colorectal surgery, but ICG-FA group patients with transection line change for insufficient blood perfusion to the anastomotic stoma after evaluation had a higher AL rate than those without transection line change. Therefore, ICG-FA can help to identify patients at high risk of AL and intercept its occurrence. Moreover, ICG-FA may reduce the overall complication rate, severe complication rate, and reoperation rate, but induce postoperative ileus. High-quality randomized-controlled trials with a placebo control are needed to further evaluate the effectiveness and safety of ICG-FA.

Indocyanine green fluorescence angiography prevents anastomotic leakage in rectal cancer surgery: a systematic review and meta-analysis

BACKGROUND

The role of intraoperative use of indocyanine green (ICG) fluorescence angiography (ICGFA) to prevent anastomotic leakage (AL) in rectal cancer surgery remains controversial.

METHODS

The systematic review for studies evaluating ICGFA in patients undergoing rectal cancer surgery in PubMed, Embase, Web of Science, and the Cochrane Library was performed up to April 30, 2020. The primary outcome was the incidence of AL. The analysis was performed using RevMan v5.3 and Stata v12.0 software.

RESULTS

Eighteen studies comprising 4038 patients were included. In the present meta-analysis, intraoperative use of ICGFA markedly reduced AL rate (OR = 0.33; 95% CI: 0.24-0.45; P < 0.0001; I² = 0%) in rectal cancer surgery, which was still significant in surgeries limited to symptomatic AL (OR = 0.44; 95% CI: 0.31-0.64; P < 0.0001; I² = 22%). This intervention was also associated with shorter postoperative stays (MD = - 1.27; 95% CI: - 2.42 to - 0.13; P = 0.04; I² = 60%). However, reoperation rate (OR = 0.61; 95% CI: 0.34-1.10; P = 0.10; I² = 6%), ileus rate (OR = 1.30; 95% CI: 0.60-2.82; P = 0.51; I² = 56%), and surgical site infection rate (OR = 1.40; 95% CI: 0.62-3.20; P = 0.42; I² = 0%) were not significantly different between the two groups.

CONCLUSION

The use of ICGFA was associated with a lower AL rate after rectal cancer resection. However, more multi-center RCTs with large sample size are required to further verify the value of ICGFA in rectal cancer surgery.

The efficacy of intraoperative ICG fluorescence angiography on anastomotic leak after resection for colorectal cancer: a meta-analysis

OBJECTIVE

The purpose of this study was to investigate whether intraoperative indocyanine green fluorescence angiography can reduce the incidence of anastomotic leak.

METHODS

Present authors conducted a systematic search of PubMed, EMBASE, and Cochrane databases for randomized controlled trials (RCTs), prospective nonrandomized trials, and retrospective trials up to March 2020. Eleven papers fulfilling the screening criteria were included.

INTERVENTION

Indocyanine green was injected intravenously after the division of the mesentery and colon but before anastomosis. The primary outcome measure was AL rate with at least 3 months of follow-up. Secondary outcome measure was operation time, postoperative complications, surgical site infection, reoperation, and ileus rate. The results were analyzed using STATA 12.0 software (Stata Corp, College Station, TX, USA).

RESULT

A total of 3137 patients were collected in 11 studies. Meta-analysis showed that compared with conventional surgery, the ICG fluorescence angiography resulted in a fewer AL rate (OR = 0.31; 95% CI 0.21 to 0.44; P < 0.0001), postoperative complications (OR = 0.70; 95% CI 0.51 to 0.96; P < 0.025), and reoperation rate (OR = 0.334; 95% CI 0.16 to 0.68; P = 0.003). Operation time (weighted mean difference - 25.162 min; 95% CI - 58.7 to 8.375; P = 0.141), surgical site infection rate (OR = 1.11; 95% CI 0.59 to 2.09; P = 0.742) did not differ between the two groups.

CONCLUSION

The result revealed that indocyanine green was associated with a lower anastomotic leakage rate after colorectal cancer resection. However, larger, multicentered, high-quality randomized controlled trials are needed to confirm the benefit of indocyanine green fluorescence angiography.

Meta-Analysis on the Efficacy of Indocyanine Green Fluorescence Angiography for Reduction of Anastomotic Leakage After Rectal Cancer Surgery

BACKGROUND

Indocyanine green (ICG) fluorescence angiography is a new technique that help surgeons to assess the blood perfusion of the anastomotic intestine. The aim of this study is to evaluate whether ICG fluorescence angiography can reduce the anastomotic leakage (AL) rate after colorectal anastomoses for rectal cancer (RC) patients.

METHODS

Studies comparing AL rates between use and nonuse of ICG fluorescence angiography up to April 2020 were systematically searched from PubMed, Embase, Web of Science, Cochrane Library, and China National Knowledge Infrastructure. A pooled analysis was performed for the available data regarding the baseline features, AL rate, and other surgical outcomes. ReMan 5.3 software was used to perform the statistical analysis. Quality evaluation and publication bias were also conducted.

RESULTS

Thirteen studies with a total of 2593 patients (1121 in the ICG group and 1472 in the control group) undergoing colorectal anastomoses after RC surgery were included. In the pooled analysis, the baseline data, operation time, and intraoperative blood loss in 2 groups were all comparable and without significant heterogeneity. However, the AL rate in the ICG group was significantly lower (OR .31; 95% CI .22-.44; P < .00001) than that in the control group. Additionally, ICG fluorescence angiography was associated with a decreased overall complication rate (OR .60; 95% CI .47-.76; P < .0001) in patients who undergo RC surgery.

CONCLUSIONS

The present study revealed that ICG fluorescence angiography reduced AL rate after colorectal anastomoses for RC patients. However, more high-quality randomized controlled trials are needed to confirm this benefit.