Evaluation of intestinal perfusion by ICG fluorescence imaging in laparoscopic colorectal surgery with DST anastomosis

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.

Blinded Intraoperative Quantitative Indocyanine Green Metrics Associate With Intestinal Margin Acceptance in Colorectal Surgery

BACKGROUND

Indocyanine green is a useful tool in colorectal surgery. Quantitative values may enhance and standardize its application.

OBJECTIVE

To determine whether quantitative indocyanine green metrics correlate with standard subjective indocyanine green perfusion assessment in acceptance or rejection of anastomotic margins.

DESIGN

Prospective single-arm, single-institution cohort study. Surgeons viewed subjective indocyanine green images but were blinded to quantitative indocyanine green metrics.

SETTING

Tertiary academic center.

PATIENTS

Adults undergoing planned intestinal resection.

MAIN OUTCOME MEASURES

Accepted perfusion and rejected perfusion of the intestinal margin were defined by the absence or presence of ischemia by subjective indocyanine green and gross inspection. The primary outcomes included quantitative indocyanine green values, maximum fluorescence, and time-to-maximum fluorescence in accepted compared to rejected perfusion. Secondary outcomes included maximum fluorescence and time-to-maximum fluorescence values in anastomotic leak.

RESULTS

There were 89 perfusion assessments comprising 156 intestinal segments. Nine segments were subjectively assessed to have poor perfusion by visual inspection and subjective indocyanine green. Maximum fluorescence (% intensity) exhibited higher intensity in accepted perfusion (accepted perfusion 161% [82%-351%] vs rejected perfusion 63% [10%-76%]; p = 0.03). Similarly, time-to-maximum fluorescence (seconds) was earlier in accepted perfusion compared to rejected perfusion (10 seconds [1-40] vs 120 seconds [90-120]; p < 0.01). Increased BMI was associated with higher maximum fluorescence. Anastomotic leak did not correlate with maximum fluorescence or time-to-maximum fluorescence.

LIMITATIONS

Small cohort study, not powered to measure the association between quantitative indocyanine green metrics and anastomotic leak.

CONCLUSIONS

We demonstrated that blinded quantitative values reliably correlate with subjective indocyanine green perfusion assessment. Time-to-maximum intensity is an important metric in perfusion evaluation. Quantitative indocyanine green metrics may enhance intraoperative intestinal perfusion assessment. Future studies may attempt to correlate quantitative indocyanine green values with anastomotic leak. See Video Abstract .

LAS MTRICAS CUANTITATIVAS INTRAOPERATORIAS CIEGAS DEL VERDE DE INDOCIANINA SE ASOCIAN CON LA ACEPTACIN DEL MARGEN INTESTINAL EN LA CIRUGA COLORRECTAL

ANTECEDENTES:El verde de indocianina es una herramienta útil en la cirugía colorrectal. Los valores cuantitativos pueden mejorar y estandarizar su aplicación.OBJETIVO:Determinar si las métricas cuantitativas de verde de indocianina se correlacionan con la evaluación subjetiva estándar de perfusión de verde de indocianina en la aceptación o rechazo de los márgenes anastomóticos.DISEÑO:Estudio de cohorte prospectivo de un solo brazo y de una sola institución. Los cirujanos vieron imágenes subjetivas de verde de indocianina, pero no conocían las métricas cuantitativas de verde de indocianina.AJUSTE:Centro académico terciario.PACIENTES:Adultos sometidos a resección intestinal planificada.PRINCIPALES MEDIDAS DE RESULTADO:La perfusión aceptada y la perfusión rechazada del margen intestinal se definieron por la ausencia o presencia de isquemia mediante verde de indocianina subjetiva y la inspección macroscópica. Los resultados primarios fueron los valores cuantitativos de verde de indocianina, la fluorescencia máxima y el tiempo hasta la fluorescencia máxima en la perfusión aceptada en comparación con la rechazada. Los resultados secundarios incluyeron la fluorescencia máxima y el tiempo hasta alcanzar los valores máximos de fluorescencia en la fuga anastomótica.RESULTADOS:Se realizaron 89 evaluaciones de perfusión, comprendiendo 156 segmentos intestinales. Se evaluó subjetivamente que 9 segmentos tenían mala perfusión mediante inspección visual y verde de indocianina subjetiva. La fluorescencia máxima (% de intensidad) mostró una mayor intensidad en la perfusión aceptada [Perfusión aceptada 161% (82-351) vs Perfusión rechazada 63% (10-76); p = 0,03]. De manera similar, el tiempo hasta la fluorescencia máxima (segundos) fue más temprano en la perfusión aceptada en comparación con la rechazada [10 s (1-40) frente a 120 s (90-120); p < 0,01]. Aumento del índice de masa corporal asociado con una fluorescencia máxima más alta. La fuga anastomótica no se correlacionó con la fluorescencia máxima ni con el tiempo hasta la fluorescencia máxima.LIMITACIONES:Estudio de cohorte pequeño, sin poder para medir la asociación entre las mediciones cuantitativas del verde de indocianina y la fuga anastomótica.CONCLUSIÓN:Demostramos que los valores cuantitativos ciegos se correlacionan de manera confiable con la evaluación subjetiva de la perfusión de verde de indocianina. El tiempo hasta la intensidad máxima es una métrica importante en la evaluación de la perfusión. Las métricas cuantitativas de verde de indocianina pueden mejorar la evaluación de la perfusión intestinal intraoperatoria. Los estudios futuros pueden intentar correlacionar los valores cuantitativos de verde de indocianina con la fuga anastomótica. (Traducción-Dr. Yolanda Colorado).

Outcomes of Anastomotic Evaluation Using Indocyanine Green Fluorescence during Minimally Invasive Esophagectomy

BACKGROUND

Limited evidence exists assessing whether anastomotic evaluation using indocyanine green fluorescence (IGF) during minimally invasive esophagectomy (MIE) predicts or improves outcomes. We hypothesized that IGF helps surgeons predict anastomotic complications and reduces anastomotic leaks after MIE.

METHODS

In September 2019, our institution began routinely using IGF for intraoperative evaluation of anastomoses during MIE. Data were collected from patients undergoing MIE in the two years before and after this technology began being routinely used. Baseline characteristics and outcomes, including anastomotic leak, in patients who underwent indocyanine green fluorescence evaluation (ICG) and those who did not (nICG) were compared. Outcomes were also compared between ICG patients with normal versus abnormal fluorescence.

RESULTS

Overall, 181 patients were included. Baseline demographic and clinical characteristics did not differ between the ICG and nICG groups. ICG patients experienced higher rates of anastomotic leak (10.2% vs. 1.6%, P = .015) and 90-day mortality (8.5% vs. 1.6%, P = .04) compared to nICG patients. Due to lack of equipment availability, 19 nICG patients underwent MIE after the use of IGF became routine, and none developed leaks. ICG patients with abnormal fluorescence had higher rates of anastomotic leak (71.4% vs 1.9%, P < .001) and 30-day mortality (28.6% vs 0%, P = .012) compared to those with normal fluorescence.

DISCUSSION

Abnormal intraoperative IGF was associated with increased rate of anastomotic leak, suggesting predictive potential of IGF. However, its use was associated with an increased leak rate and higher mortality. Further studies are warranted to assess possible physiologic effects of indocyanine green on the esophageal anastomosis.

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%.

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.

Discontinuity of marginal artery at splenic flexure and rectosigmoid junction: A systematic review and meta-analysis

AIM

The aim of this study was to provide comprehensive evidence-based assessment of the discontinuity of the marginal artery at the splenic flexure (SF) and the rectosigmoid junction (RSJ).

METHOD

A systematic review was conducted of literature published to 26 December 2022 in the electronic databases PubMed, SCOPUS and Web of Science to identify studies eligible for inclusion. Data were extracted and pooled into a meta-analysis using the Metafor package in R. The primary outcomes were the pooled PPEs of the marginal artery at the SF and the RSJ. The secondary outcome was the size of vascular anastomoses.

RESULTS

A total of 21 studies (n = 2,864 patients) were included. The marginal artery was present at the splenic flexure in 82% (95% CI: 62-95) of patients. Approximately 81% (95% CI: 63-94%) of patients had a large macroscopic anastomosis, while the remainder (19%) had small bridging ramifications forming the vessel. The marginal artery was present at the RSJ in 82% (95% CI: 70-91%) of patients.

CONCLUSION

The marginal artery may be absent at the SF and the RSJ in up to 18% of individuals, which may confer a higher risk of ischaemic colitis. As a result of high interstudy heterogeneity noted in our analysis, further well-powered studies to clarify the prevalence of the marginal artery at the SF and the RSJ, as well as its relationship with other complementary colonic collaterals (intermediate and central mesenteric), are warranted.

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.

Indocyanine green angiography for lower incidence of anastomotic leakage after transanal total mesorectal excision: a propensity score-matched cohort study

Background

Anastomotic leakage (AL) is the most serious complication that can arise during colorectal surgery. Indocyanine green (ICG) angiography offers an intraoperative assessment of colonic vascular perfusion in real time. We aimed to assess ICG's effects on the AL rate in patients who have undergone transanal total mesorectal excision (TaTME) for rectal cancer.

Methods

This retrospective cohort study was conducted at our center from October 2018 to March 2022 to analyze the clinical data of patients with rectal cancer who have undergone TaTME after propensity score matching (PSM). The primary outcome was the proximal colonic transection line modification and clinical AL rate.

Results

A total of 143 patients in the non-ICG group and 143 patients in the ICG group were included after PSM. The proximal colonic transection line of seven patients in the non-ICG group was modified, while 18 were in the ICG group (4.9% vs. 12.5%, p = 0.023). Twenty-three patients (16.1%) in the non-ICG group and five patients (3.5%) in the ICG group were diagnosed with AL (p < 0.001). The ICG group had a less hospital readmission rate than the non-ICG group (0.7% vs. 7.7%, p = 0.003). The between-group differences in basic line and other outcomes were not significant.

Conclusions

ICG angiography is a safe and feasible method to help surgeons identify potentially poor colonic vascular perfusion and modify the proximal colonic transection line, resulting in a significant reduction in AL and hospital readmission rates.

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.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

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).

Intraoperative Indocyanine Green Imaging for the Evaluation of Blood Perfusion Area in Cancer of the Splenic Flexure With an Occluded Inferior Mesenteric Artery: A Report of Two Cases

Radical resection for cancer of the splenic flexure requires careful consideration of the dissection line so that blood flow in the remnant bowel is maintained, particularly when the root of the inferior mesenteric artery (IMA) is already occluded. Intraoperative indocyanine green (ICG) imaging is a promising method for evaluating blood perfusion of organs and vessels. However, there are few reports on the use of ICG to determine the dissection line in patients with altered blood flow. In this article, we describe two cases of successful resection of splenic flexure cancer (SFC) in patients with an occluded IMA under ICG guidance. Case one was a 76-year-old man with a diagnosis of stage III SFC who had previously undergone endovascular aortic repair without reimplantation of the IMA. Intraoperative ICG imaging revealed that the left side of the colon was perfused mainly by the left branch of the middle colic artery (MCA). We performed a hemicolectomy with preservation of the MCA-left colic artery (LCA) arcade and resected an enlarged lymph node en bloc. Case two was a 77-year-old man with a diagnosis of stage II SFC in whom the root of the IMA appeared to be occluded by arteriosclerosis. Computed tomography showed that the LCA was anastomosed to the accessory middle colic artery (AMCA) while the left branch of the MCA was joined to the marginal artery. Intraoperative ICG imaging revealed that the left side of the colon was perfused by the AMCA and not the MCA. By preserving the AMCA-LCA arcade, we were able to safely divide the left branch of the MCA. Both patients were discharged with no symptoms of bowel ischemia or recurrence of cancer during follow-up. Interindividual variation in vessel branching patterns and dominant vessels in the descending and distal transverse colon may result from congenital factors or acquired disease. Detailed information on blood perfusion is required to avoid postoperative bowel ischemia. This report is the first to focus on patients with SFC and altered blood flow. We show that ICG imaging might be a reasonable option for determining an adequate surgical dissection area.

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

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

Significance of information obtained during transanal drainage tube placement after anterior resection of colorectal cancer

Introduction

It has recently been reported that the placement of a transanal drainage tube after rectal cancer surgery reduces the rate of anastomotic leakage. However, transanal drainage tube cannot completely prevent anastomotic leakage and the management of transanal drainage tube needs to devise. We investigated the information obtained during transanal drainage tube placement and evaluated the relationship between these factors and anastomotic leakage.

Patients and methods

Fifty-one patients who underwent anterior resection of rectal cancer was retrospectively reviewed. transanal drainage tube was placed for more than 5 days after surgery. The daily fecal volume from transanal drainage tube was measured on postoperative day 1–5, and the defecation during transanal drainage tube placement was investigated.

Results

Anastomotic leakage during transanal drainage tube placement occurred in 4 patients. The anastomotic leakage rate during transanal drainage tube placement in patients whose maximum daily fecal volume or total fecal volume from the transanal drainage tube during postoperative days 1–5 was large was significantly higher than that in patients whose fecal volume was small. The anastomotic leakage rate of the patients with intentional defecation during transanal drainage tube placement was significantly higher than that of the patients without intentional defecation during transanal drainage tube placement. The maximum daily fecal volume and the total fecal volume from the transanal drainage tube during postoperative days 1–5 in patients who experienced intentional defecation during transanal drainage tube placement was significantly higher than that of patients without intentional defecation during transanal drainage tube placement.

Conclusion

A large fecal volume from transanal drainage tube after anterior rectal resection or intentional defecation in patients with transanal drainage tube placement were suggested to be risk factors for anastomotic leakage.

Quantitative Analysis of Colonic Perfusion Using ICG Fluorescence Angiography and Its Consequences for Anastomotic Healing in a Rat Model

Forty-three rats were randomly assigned to the following four groups: non-ischemic group (Control Group), 1 cm-long ischemic group (Group 1), 2 cm-long ischemic group (Group 2), and 3 cm-long ischemic group (Group 3). The rates of AL were 0% (0/10) in the Control Group, 22.2% (2/9) in Group 1, 25% (2/8) in Group 2, and 50% (4/8) in Group 3. The bursting pressure of the Control Group was significantly higher than that of the other groups (p < 0.01). Regarding the pathological findings, the granulation thickness and the number of blood vessels at the anastomosed site were significantly higher in the Control Group than in Group 3 (p < 0.05). Receiver operating characteristics analysis revealed that Slope was the most significant predictor of AL, with an area under the curve of 0.861. When the cutoff value of Slope was 0.4, the sensitivity and specificity for the prediction of AL were 75% and 81.4%, respectively. Quantitative analysis of ICG fluorescence angiography could predict AL in a rat model.

Correlation between Colon Perfusion and Postoperative Fecal Output through a Transanal Drainage Tube during Laparoscopic Low Anterior Resection

In order to prevent anastomotic leakage (AL) following rectal surgery, various solutions—such as intraoperative indocyanine green (ICG) angiography and transanal drainage tubes (TDT)—have been proposed. This study investigated the relationship between intestinal perfusion and fecal volume through TDT in laparoscopic low anterior resection (LAR). A total of 59 rectal cancer patients who underwent laparoscopic LAR with both intraoperative ICG angiography and postoperative TDT placement were retrospectively analyzed. The relationship between intestinal perfusion and fecal volume through TDT was examined. Based on the ICG fluorescence, the transection site was shifted more proximally in 20 cases (33.9%). Symptomatic AL occurred in seven patients (11.8%). The AL rate of the patients whose daily fecal volume exceeded 100 mL/day in 2 or more days was significantly higher than that of those whose daily fecal volume exceeded it in 0 or 1 day (44.4% vs. 6.0%; p < 0.01). Univariate and multivariate analyses showed that the need for a proximal shift of the transection site was significantly associated with a high fecal volume. The quantitative analysis of ICG fluorescence indicated that Fmax (the fluorescence difference between the baseline and maximum) was significantly associated with fecal volume through TDT.

Mesenteric occlusive disease of the inferior mesenteric artery is associated with anastomotic leak after left-sided colon and rectal cancer surgery: a retrospective cohort study

PURPOSE

Anastomotic leak (AL) is a serious complication following colorectal surgery. Atherosclerosis causes inadequate anastomotic perfusion and is suggested to be a risk factor for AL. The aim of this study was to investigate the association of mesenteric occlusive disease on preoperative computed tomography (CT) scan with AL after left-sided colon or rectal cancer surgery.

METHODS

This was a retrospective, multicenter cohort study including 1273 patients that underwent left-sided or rectal cancer resection between 2009 and 2018 from three hospitals in the Netherlands. AL patients were 1:1 matched with non-leak patients and preoperative contrast-enhanced CT-scans were retrospectively analyzed for mesenteric atherosclerotic lesions. The main outcome measure was the presence of mesenteric occlusive disease on the preoperative CT-scan.

RESULTS

Anastomotic leak developed in 6% of 1273 patients (N = 76). Low anterior resection and stage I-III disease were statistically significant associated with AL (p = 0.01, p = 0.04). No other statistically significant differences in patient characteristics between AL and non-leak patients were found. A clinically significant stenosis (≥ 70-100%) of the inferior mesenteric artery was statistically significant more frequent present in AL patients, compared to non-leak patients (p < 0.01). No statistically significant differences in the presence of mesenteric occlusive disease of the celiac artery and superior mesenteric artery between AL patients and non-leak patients were found.

CONCLUSION

Mesenteric occlusive disease of the IMA on preoperative CT-scan is associated with AL after left-sided colon or rectal resection for cancer. Preoperative identification of high-risk patients with a preoperative CT-scan of the mesenteric vasculature might be useful to reduce the risk of AL.

Single Snapshot Imaging of Optical Properties (SSOP) for Perfusion Assessment during Gastric Conduit Creation for Esophagectomy: An Experimental Study on Pigs

Simple Summary

Anastomotic leak is the most dangerous complication occurring after esophagectomy and its relationship with inadequate visceral perfusion is widely recognized. Currently, the adequate perfusion of the gastric conduit is intraoperatively assessed by surgeons using subjective indicators (e.g., serosal color or pulsatile flow of vessels). During the last decades, several innovative optical techniques based on the interaction of light with tissue have been developed to monitor perfusion in esophagogastric surgery. However, these innovative approaches are characterized by a lack of video rate and reproducibility. They also provide operator-dependent results and lengthen the surgical workflow. Single Snapshot imaging of Optical Properties (SSOP) is an optical technique, which can overcome such limitations, providing quantitative information on the optical properties of biological tissues over a large field of view. It is the first study to demonstrate the accuracy of SSOP in the quantification of serosal StO₂% in a porcine gastric conduit model.

Abstract

Anastomotic leakage (AL) is a serious complication occurring after esophagectomy. The current knowledge suggests that inadequate intraoperative perfusion in the anastomotic site contributes to an increase in the AL rate. Presently, clinical estimation undertaken by surgeons is not accurate and new technology is necessary to improve the intraoperative assessment of tissue oxygenation. In the present study, we demonstrate the application of a novel optical technology, namely Single Snapshot imaging of Optical Properties (SSOP), used to quantify StO₂% in an open surgery experimental gastric conduit (GC) model. After the creation of a gastric conduit, local StO₂% was measured with a preclinical SSOP system for 60 min in the antrum (ROI-A), corpus (ROI-C), and fundus (ROI-F). The removed region (ROI-R) acted as ischemic control. ROI-R had statistically significant lower StO₂% when compared to all other ROIs at T15, T30, T45, and T60 (p < 0.0001). Local capillary lactates (LCLs) and StO₂% correlation was statistically significant (R = −0.8439, 95% CI −0.9367 to −0.6407, p < 0.0001). Finally, SSOP could discriminate resected from perfused regions and ROI-A from ROI-F (the future anastomotic site). In conclusion, SSOP could well be a suitable technology to assess intraoperative perfusion of GC, providing consistent StO₂% quantification and ROIs discrimination.

Indocyanine green fluorescence angiography in colorrectal surgery. First case series in Mexico

INTRODUCTION AND AIM

Anastomosis leak occurs in 1-19% of colorrectal surgeries. Our objective was to present the first Mexican case series on colorrectal surgery using indocyanine green fluorescence angiography to evaluate perfusion prior to carrying out the anastomosis.

MATERIALS AND METHODS

A retrospective, analytic, descriptive study was conducted. We studied the case records of consecutive patients that underwent colorrectal surgery with indocyanine green angiography performed by the same group of colorrectal surgeons.

RESULTS

Twenty-one case records were reviewed. Eleven (52.3%) of the patients were women, mean patient age was 57 years (38-82), and mean body mass index was 25 kg/m² (17-34). Fifteen (71.4%) patients were diagnosed with malignant disease. Indocyanine green angiography changed our therapeutic decision in three (14.2%) patients. Two colorrectal anastomoses (14.2%) were performed at fewer than 5 cm from the anal verge and 13 (61.9%) were performed at more than 5 cm from the anal verge. Three of the anastomoses were ileocolic (14.2%), two were coloanal (9.5%), and one was ileoanal (4.7%). There were six (28.5%) complications, no cases of anastomotic leak, and no complications associated with the use of indocyanine green. The mortality rate was 0%.

CONCLUSION

The present case series is the first on colorrectal surgery conducted in Mexico using indocyanine green fluorescence angiography, with excellent results.

Strategy to Avoid Anastomotic Leakage in Laparoscopic Colorectal Resection Using the Indocyanine Green Fluorescence System

Purpose

Anastomotic leakage (AL) in colorectal resections is often caused by insufficient blood flow to the stump. Injecting indocyanine green can help detect blood flow intraoperatively. In this study, we evaluated our original strategy using an indocyanine green fluorescence system to avoid AL.

Methods

We retrospectively evaluated 79 patients who underwent laparoscopic colorectal resection for colon cancer using a double-stapling technique. Blood flow in oral stumps was evaluated by measuring indocyanine green fluorescence time (FT). We investigated AL cases in detail and analyzed correlations between FT and risk factors for AL.

Results

Of the 79 patients, 7 (8.9%) developed AL. We divided patients by FTs: &gt;60 seconds, 50 to 60 seconds, and &lt;50 seconds. The AL rates were FT &gt;60 seconds, 60%; FT 50 to 60 seconds, 10.3%; and FT &lt;50 seconds, 2.2%. The AL rate of high-risk cases (with more than 2 risk factors) were calculated and we made our original strategy to avoid AL as the following. Further resection or diverting stomas were needed by the FT &gt;60 seconds group, and by members of the FT 50 to 60 seconds group with ≥3 risk factors. The FT &lt;60 seconds group needed no additional management.

Conclusions

Patients with delayed FT (&gt;60 seconds, or 50–60 seconds with ≥3 risk factors) may need revision of the anastomosis (diverting stoma or additional resection) to avoid AL. Our original strategy may contribute to reduce AL in colorectal operations.

Optimization of indocyanine green angiography for colon perfusion during laparoscopic colorectal surgery

AIM

This study aims to evaluate the extrinsic effects of conditional factors affecting quantitative parameters and to establish the optimization of indocyanine green (ICG) angiography using in vitro experiments and a prospective observational study.

METHOD

In vitro experiments were performed to evaluate the correlation between conditional factors such as camera distance, surrounding lighting, fluorescence emission sources and ICG doses. The fluorescence intensity was measured from the ICG-containing test tube in each condition. In the clinical study, ICG angiography was applied to patients with colorectal cancer (n = 164). The quantitative perfusion parameters were the maximal fluorescence intensity (F_MAX ), slope, T_1/2MAX and perfusion time ratio (TR). Camera position, distance to colon, fluorescence emission source, surrounding lighting, site of angiography and ICG specific mode were considered as conditional factors and compared with the quantitative parameters to identify the optimal condition of ICG angiography.

RESULTS

The fluorescence intensity had an inverse correlation with distance, and the transitional zone was shown at a distance of 4-5 cm by slope differential. F_MAX , T_1/2MAX and slope were affected significantly by camera distance, site of angiography, fluorescence emission source and ICG mode as conditional factors. On multivariate analysis, F_MAX was independently associated with spectral ICG mode with red inversion, laser mode and camera distance. Conversely, TR was not related to any conditional factors.

CONCLUSION

Since quantitative parameters of ICG angiography are influenced by various conditions, a standardized protocol is required. The application of ICG specific modes with a constant distance of 4-5 cm can provide optimized fluorescence images.

Usefulness of a finger-mounted tissue oximeter with near-infrared spectroscopy for evaluating the intestinal oxygenation and viability in rats

PURPOSE

To investigate the utility of the device for evaluating intestinal oxygenation and viability using an animal model.

METHODS

Sprague-Dawley rats underwent laparotomy under general anesthesia, and the blood vessels in the terminal ileum were clamped to create ischemia. We measured the regional tissue oxygenation saturation (rSO2) using an oximeter after 1, 3, and 6 h of vessel clamping. Ischemic tissue damage was assessed using a histological score. The intestine was reperfused after each clamping period, and intestinal rSO2 and survival rate were evaluated.

RESULTS

When reperfusion was performed at 1 and 3 h after ischemia, rSO2 increased after 10 min, and it improved to the same level as for normal intestine after 1 h; all rats survived for 1 week. In contrast, after 6 h of ischemia, rSO2 did not increase after reperfusion, and all animals died within 2 days. The histological scores increased after 1 h of reperfusion, with longer clamping periods.

CONCLUSION

A finger-mounted tissue oximeter could evaluate intestinal ischemia and the viability, which is thus considered to be a promising result for future clinical application.

Extended Left Colectomy with Coloanal Anastomosis by Indocyanine Green-guided Deloyers Procedure: A Case Report

The Deloyers procedure is performed after extended left colectomy, enabling the reach of the proximal colon to the rectum for anastomosis while preserving sufficient blood supply. We report a case of the Deloyers procedure performed safely under indocyanine green (ICG) fluorescence guidance. A 50-year-old man with obesity (body mass index, 35.7 kg/m²) and a history of diabetes underwent an extended left hemicolectomy and ultralow anterior resection of the rectum as radical resection for transverse and sigmoid colon cancers and a lower rectal neuroendocrine tumor. Reconstruction was performed by the Deloyers procedure. A necessary length of the transverse colon with reduced blood flow was additionally resected under ICG fluorescence guidance, and a transanal hand-sewn coloanal anastomosis was performed. This is the first report in which the Deloyers procedure was performed successfully with the ICG fluorescence method. ICG fluorescence may be useful when combined with the Deloyers procedure.

Fluorescence-Based Quantification of Gastrointestinal Perfusion: A Step Towards an Automated Approach

Background: Qualitative fluorescence angiography (FA) provides insights into intestinal tissue perfusion, but today it is not yet accurate in predicting anastomotic leakage. To improve peroperative detection of impaired perfusion, quantified parameters should be investigated using a standardized method. The aim of this study was to develop a (semi)automated algorithm for comprehensive and convenient analysis of FA parameters. Materials and Methods: An analysis tool was developed for the extraction of quantified FA parameters. The start- and endpoint of intensity increase (T₀ and Tmax) were automatically detected in the intensity-time curves. Algorithm performance was measured against manual assignment of T₀ and Tmax by 9 independent observers in 18 in vivo generated test signals, using the intraclass correlation coefficient (ICC). Characteristics of parameter T1∕2 (time to 50% of maximal intensity) were analyzed in normally perfused small intestine of 32 subjects who underwent robotic laparoscopic surgery. Since ethical approval was not required under the Dutch law, the need for informed consent was waived. Results: Automated detection of T₀ and Tmax was successful in all subjects. Output of the algorithm had an excellent agreement with the median of the human observations: ICC = 0.95 (95% confidence interval: 0.86-0.96). Overall, T1∕2 had a median value of 5.1 (interquartile range = 2.4) seconds and a minimal and maximal value of 1.3 and 9.9 seconds, respectively. Conclusions: The presented method provided convenient data analysis in the search for effective FA quantification. Future research should expand the data to find adequate threshold values for peroperatively identifying insufficient perfusion and investigate the influence of physiological conditions.

Intra-operative assessment of left-sided colorectal anastomotic integrity: a systematic review of available techniques

AIM

Anastomotic leak (AL) after colorectal resection is associated with increased rates of morbidity and mortality: potential permanent stoma formation, increased local recurrence, reduced cancer-related survival, poor functional outcomes and associated quality of life. Techniques to reduce leak rates are therefore highly sought.

METHOD

A literature search was performed for published full text articles using PubMed, Cochrane and Scopus databases with a focus on colorectal surgery 1990-2020. Additional papers were detected by scanning references of relevant papers.

RESULTS

A total of 53 papers were included after a thorough literature search. Techniques assessed included leak tests, endoscopy, perfusion assessment and fluorescence studies. Air-leak testing remains the most commonly used method across Europe, due to ease of reproducibility and low cost. There is no evidence that this reduces the leak rate; however, identification of a leak intra-operatively provides the opportunity for either suture reinforcement or formal takedown with or without re-do of the anastomosis and consideration of diversion. Suture repair alone of a positive air-leak test is associated with an increased AL rate. The use of fluorescence studies to guide the site of anastomosis has demonstrated reduced leak rates in distal anastomoses, is safe, feasible and has a promising future.

CONCLUSION

Although over reliance on any assessment tool should be avoided, intra-operative techniques with the aim of reducing AL rates are increasingly being employed. Standardization of these methods is imperative for routine use. However, in the interim it is recommended that all anastomoses should be assessed intra-operatively for mechanical failure, particularly distal anastomoses.

Clinical and oncological outcomes of the low ligation of the inferior mesenteric artery with robotic surgery in patients with rectal cancer following neoadjuvant chemoradiotherapy

Background/aim

The aim of this study is to compare clinical and oncologic outcomes of the high and low ligation techniques of the inferior mesenteric artery (IMA) in rectal cancer patients treated with robotic surgery after neoadjuvant chemoradiotherapy (nCRT).

Materials and methods

In this retrospective study, 77 patients with T3/T4-node negative rectal cancer with tumor penetration through the muscle wall (Stage 2) or node positive disease without distant metastases (Stage 3) who were treated electively with robotic surgical resection following nCRT at a single institution between January 2014 and January 2018 were analyzed. Patients were divided into 2 groups (38 patients were included in the low ligation group and 39 patients in the high ligation group).

Results

There was no statistical difference between the high ligation group and low ligation group in univariate analysis for 2-year overall survival and disease-free survival (OR = 1.146; 95% CI = 0.274 to 4.797; P = 0.950, and OR = 1.141; 95% CI = 0.564 to 2.308; P = 0.713, respectively). There was no significant difference between the 2 groups in the mean number of harvested lymph nodes and mean number of metastatic lymph nodes (P = 0.980 and P = 0.124, respectively). Anastomosis stricture was observed significantly less frequently in the low ligation group versus the high ligation group (2.6% and 28.2%, respectively) (P = 0.002). Also, the difference for the median length of hospital stay for the high and low ligation groups was statistically significant in favor of the low ligation group (P = 0.011).

Conclusion

In robotic rectal surgery, the low ligation technique of the IMA can reduce the rate of anastomosis stricture and provide similar oncological results as the high ligation technique.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

TRIAL REGISTRATION

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

Efficacy of intraoperative ICG fluorescence imaging evaluation for preventing anastomotic leakage after left-sided colon or rectal cancer surgery: a propensity score-matched analysis

BACKGROUND

Intestinal perfusion at the anastomotic site is thought to be one of the most influential risk factors for postoperative anastomotic leakage (AL). We evaluated the efficacy of indocyanine green (ICG) fluorescence imaging at the stump of the proximal colon in left-sided colectomy or rectal resection in terms of decreasing the incidence of AL.

METHODS

Prospectively collected data were retrospectively evaluated. Patients who underwent left-sided colectomy or rectal resection were enrolled (ICG group; n = 197), and patients who had undergone a similar procedure before the ICG group were enrolled from the charts as historical controls (HC group; n = 187). After ICG evaluation, anastomosis was performed where fluorescence was sufficient. The incidence of AL was compared between the ICG and HC groups. Propensity score (PS)-matched data were analyzed to clarify the risk of AL.

RESULTS

AL occurred in 6 patients (3.3%) in the ICG group and 17 (10.7%) in the HC group. ICG evaluation revealed 179 patients with good fluorescence and 18 with poor/none perfusion (9.1%). The transection line was changed in all patients with poor/none fluorescence. Three of these 18 patients developed AL (16.7%), though transection line was changed at which is thought to be good. We hope AL in poor/none fluorescence can be prevented at the same rate of cases with good fluorescence. Actually, the rate of that was significantly higher compared with good fluorescence patients (P = 0.038). 93 patients in each group were compared by PS-matched data analysis, which showed the AL rate in the ICG group was significantly lower than that in the HC group (3.2% vs 10.8%, respectively; P = 0.046).

CONCLUSIONS

Even though this study has limitations of comparison of data prospectively collected and retrospectively analyzed, intraoperative ICG fluorescence imaging evaluation could significantly decrease the incidence of AL.

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.

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.

Comparison of hyperspectral imaging and fluorescence angiography for the determination of the transection margin in colorectal resections-a comparative study

PURPOSE

One relevant aspect for anastomotic leakage in colorectal surgery is blood perfusion of both ends of the anastomosis. The clinical evaluation of this issue is limited, but new methods like fluorescence angiography with indocyanine green or non-invasive and contactless hyperspectral imaging have evolved as objective parameters for perfusion evaluation.

METHODS

In this prospective, non-randomized, open-label and two-arm study, fluorescence angiography and hyperspectral imaging were compared in 32 consecutive patients with each other and with the clinical assessment by the surgeon. After preparation of the bowel and determination of the surgical resection line, the tissue was evaluated with hyperspectral imaging for 5 min before and after cutting the marginal artery and assessed by 6 hyperspectral pictures followed by fluorescence angiography with indocyanine green.

RESULTS

In 30 of 32 patients, the image data could be evaluated and compared. Both methods provided a comparable borderline between well-perfused and poorly perfused tissue (p = 0.704). In 15 cases, the surgical resection line was shifted to the central position due to the imaging. The border zone was sharper in fluorescence angiography and best assessed 31 s after injection. With hyperspectral imaging, the border zone was visualized wider and with more differences between proximal and distal border.

CONCLUSION

Hyperspectral imaging and fluorescence angiography provide similar results in determining the perfusion border. Both methods allow a good and safe visualization of the blood perfusion at the central resection margin to create a well-perfused anastomosis.

TRIAL REGISTRATION

This study was registered at Clinicaltrials.gov ( NCT04226781 ) on January 13, 2020.

Indocyanine green fluorescence imaging via endoscopic nasal biliary drainage during laparoscopic deroofing of liver cysts

Laparoscopic deroofing of liver cysts is widely accepted as the treatment of symptomatic huge liver cysts. As bile leakage is a common complication of this procedure, indocyanine green (ICG) imaging has played an active role in detecting intrahepatic biliary tract. However, infusion ICG imaging needs time rag after injection due to moving from bloodstream to bile, and also, additional injection is needed when the fluorescent imaging is not clear. To cover this weakness of ICG imaging, we first applied ICG imaging via 5-Fr endoscopic nasal biliary drainage (ENBD) during laparoscopic deroofing of liver cysts. This technique promptly gives us ICG imaging after ICG injection from ENBD; in addition, direct ICG imaging sometimes reveals minor leakage from sealing line and staple lines; therefore, we believe that direct ICG imaging via ENBD helps us to prevent post-operative bile leakage.

Indocyanine green fluorescence angiography in colorrectal surgery. First case series in Mexico

INTRODUCTION AND AIM

Anastomotic leak occurs in 1-19% of colorrectal surgeries. Our objective was to present the first Mexican case series on colorrectal surgery using indocyanine green fluorescence angiography to evaluate perfusion prior to carrying out the anastomosis.

MATERIALS AND METHODS

A retrospective, analytic, descriptive study was conducted. We studied the case records of consecutive patients that underwent colorrectal surgery with indocyanine green angiography performed by the same group of colorrectal surgeons.

RESULTS

Twenty-one case records were reviewed. Eleven (52.3%) of the patients were women, mean patient age was 57 years (38-82), and mean body mass index was 25 kg/m2 (17-34). Fifteen (71.4%) patients were diagnosed with malignant disease. Indocyanine green angiography changed our therapeutic decision in three (14.2%) patients. Two colorrectal anastomoses (14.2%) were performed at fewer than 5 cm from the anal verge and 13 (61.9%) were performed at more than 5 cm from the anal verge. Three of the anastomoses were ileocolic (14.2%), two were coloanal (9.5%), and one was ileoanal (4.7%). There were six (28.5%) complications, no cases of anastomotic leak, and no complications associated with the use of indocyanine green. The mortality rate was 0%.

CONCLUSION

The present case series is the first on colorrectal surgery conducted in Mexico using indocyanine green fluorescence angiography, with excellent results.

Utility of ICG fluorescence imaging with vessel clamp for ileocecal resection while preserving ileal conduit constructed after previous total cystectomy

Background

Indocyanine green (ICG) is useful for evaluating the intestinal perfusion of anastomosis. Especially for patients with prior surgeries, ICG imaging enables surgeons in visualizing the anatomical field. Here, we reported the positive and negative staining techniques of ICG fluorescence with vessel clamp for determining the optimal resection area of vessels and mesentery.

Case presentation

An 80-year-old man, who had an ileal conduit constructed after a prior total cystectomy, was diagnosed with ascending colon cancer. Although the tumor-feeding vessel was primarily the ileocecal artery, there was no detailed information about the blood running through the ileal conduit. At first, the ascending colon and the marginal vessels were transected at distal side of the tumor. Next, both, the ileocecal artery and the marginal artery of oral side of the ileal anastomotic site were clamped. Finally, we injected ICG intravenously to assess the blood flow. As a result, the blood flow between the ileal anastomotic site and transected ascending colon was not identified (negative staining). Therefore, we cut the root of the ileocecal artery, and dissected the peripheral mesocolon including the ileal anastomotic site. After the ileo-ascending colon anastomosis, we injected ICG intravenously again. The blood flow to the ileal conduit was preserved (positive staining).

Conclusion

ICG fluorescence imaging with vessel clamp can clearly visualize the demarcation line between ischemic and non-ischemic intestinal tract. In colorectal surgeries, this technique is useful to assess the anastomotic perfusion and determine optimal dissection area of vessels and mesentery in secondary intestinal surgery.

Laparoscopic left hemicolectomy with regional lymph node navigation and intracorporeal anastomosis for splenic flexure colon cancer

Laparoscopic approaches have become a standard strategy for colon cancer patients who undergo surgical treatment. Complete mesocolic excision (CME) with central vascular ligation (CVL) is the fundamental principle of radical resection of colon cancers. Splenic flexure colon cancer (SFCC) is rare, accounting for less than 4% of all colorectal cancer cases. Moreover, a laparoscopic approach for SFCC following the CME/CVL concept can be challenging because the blood supply of the splenic flexure is derived from either the middle colic artery (MCA) branching from the superior mesenteric artery, the left colic artery (LCA) branching from the inferior mesenteric artery. In addition, approximately one third of SFCC patients have an accessory MCA that can originate from the celiac trunk. Herein, we describe the technical procedure of a laparoscopic left hemicolectomy for SFCC using indocyanine green (ICG) for necessary and sufficient lymphadenectomy followed by intracorporeal anastomosis. Two injections of ICG (0.5 mg/0.2 ml × 2) into the subserosa of the proximal and distal sides of the tumor preceded the surgical procedure after pneumoperitoneum. Near infrared images obtained throughout the laparoscopic procedure helped visualize lymphatic drainage vessels and inform decision making for determining vessels requiring ligation according to the CVL concept: MCA, LCA or accessory MCA. Complete intracorporeal anastomosis following necessary and sufficient lymphadenectomy with ICG can minimize the dissecting area of the laparoscopic left hemicolectomy for SFCC patients. Intravenous ICG injection (2.5 mg) after anastomosis helps confirm blood perfusion at the anastomosis site. Four patients with SFCC underwent a laparoscopic colectomy under ICG navigation in 2019 at our institute. The median operative time was 237 min, the median estimated blood loss was 0 ml, and the median number of dissected lymph nodes was 13. No patients experienced postoperative complications. In conclusion, laparoscopic left hemicolectomy with ICG navigation and intracorporeal anastomosis for SFCC patients may be a feasible option for the radical resection of colon cancer.

Standardized Step-by-step Technique Using Surgical Landmarks in Robotic Lateral Pelvic Lymph Node Dissection

We aimed to show that a standardized step-by-step robotic approach using surgical landmarks could make lateral pelvic lymph node dissection (LPND) less complicated. We performed robot-assisted LPND consisting of 4 steps using surgical landmarks. The first step is a dissection of uretero-hypogastric fascia, which envelopes the ureter and the hypogastric nerve. The second step is a dissection of the medial side of the external iliac vein located at the lateral border of the obturator lymph nodes (LNs) group. The third step is a dissection of the vesico-hypogastric fascia, which is at the medial border of the obturator LNs group. The final step is a dissection of the internal iliac artery until the Alcock’s canal. Indocyanine green was injected just before surgery around the dentate line to identify the lateral pelvic LNs. Standardization using a robotic approach for LPND guided by surgical landmarks allows a safer and more effective surgery.

Indocyanine Green-Enhanced Colorectal Surgery-between Being Superfluous and Being a Game-Changer

Nowadays, surgical innovations incorporate new technological conquests and must be validated by evidence-based medicine. The use of augmented reality-assisted indocyanine green (ICG) fluorescence has generated a myriad of intraoperative applications such as demonstration of key anatomical landmarks, sentinel lymph nodes, and real-time assessment of local blood flow. This paper presents a systematic review of the clinical evidence regarding the applications of ICG near-infrared (NIR) fluorescence in colorectal surgery. After we removed duplicate publications and screened for eligibility, a total of 36 articles were evaluated: 23 on perfusion assessment, 10 on lymph node mapping, and 3 on intraoperative identification of ureters. Lack of homogenous studies, low statistical power, and confounding evidence were found to be common amongst publications supporting the use of ICG in colorectal surgery, raising concerns over this seductive technique's cost efficiency and redundancy. The compiled data showed that ICG NIR fluorescence may be a game-changer in particular situations, as proven for low colorectal anastomosis or lateral pelvic lymph node dissection, but it remains controversial for routine use and sentinel lymph node assessment. Further randomized studies are needed to confirm these conclusions. Future research directions include tumor-targeted fluorescence imaging and digital software for quantitative evaluation of fluorescence.

Intraoperative fluorescence angiography and risk factors of anastomotic leakage in mini-invasive low rectal resections

BACKGROUND

One of the prerequisites for proper healing of the anastomosis after a colorectal resection is adequate blood supply to the connected intestinal segments. It has been proposed that adequate visualization of the blood flow using indocyanine green (ICG) could lead to the reduction in the incidence of anastomotic leakage (AL). The aim of this study was to assess the effectiveness of intraoperative fluorescence angiography (FA) in decreasing the incidence of AL after minimally invasive low anterior resection (LAR) with total mesorectal excision (TME) in rectal cancer patients and to determine predictors of anastomotic leak.

METHODS

From August 2015 to January 2019, data from 100 patients who underwent mini-invasive TME for rectal cancer using FA with indocyanine green (ICG) were prospectively collected and analyzed. They were compared with retrospectively analyzed data from a historical control group operated by one team of surgeons before the introduction of FA from November 2012 to August 2015 (100 patients). All patients from both groups were operated sequentially in one oncological center in Nový Jičín.

RESULTS

The incidence of AL was significantly lower in the ICG group (19% vs. 9%, p = 0.042, χ² test). In fifteen patients in the ICG group (15%), the resection line was moved due to insufficient perfusion. Using Pearson's χ² test, diabetes (p = 0.036) and application of a transanal drain (NoCoil) (p = 0.032) were identified as other risk factors (RFs) for AL.

CONCLUSION

The use of ICG to visualize tissue perfusion in low rectal resections for cancer can lead to a reduction of AL.

Intraoperative fluorescence angiography with indocyanine green: retrospective evaluation and detailed analysis of our single-center 5-year experience focused on colorectal surgery

Objectives

Assessing bowel perfusion with indocyanine green fluorescence angiography (ICG-FA) shows positive effects on anastomotic healing in colorectal surgery.

Methods

A retrospective evaluation of 296 colorectal resections where we performed ICG-FA was undertaken from January 2014 until December 2018. Perfusion of the bowel ends measured with ICG-FA was compared to the visual assessment before and after performing the anastomosis. According to the observations, the operative strategy was confirmed or changed. Sixty-seven low anterior rectal resections (LARs) and 76 right hemicolectomies were evaluated statistically, as ICG-FA was logistically not available for every patient in our service and thus a control group for comparison resulted.

Results

The operative strategy based on the ICG-FA results was changed in 48 patients (16.2%), from which only one developed an anastomotic leakage (AL) (2.1%). The overall AL rate was calculated as 5.4%. Within the 67 patients with LAR, the strategy was changed in 11 patients (16.4%). No leakage was seen in those. In total three AL happened (4.5%), which was three times lower than the AL rate of 13.6% in the control group but statistically not significant. From the 76 right hemicolectomies a strategy change was undertaken in 10 patients (13.2%), from which only one developed an AL. This was the only AL reported in the whole group (1.3%), which was six times lower than the leakage rate of the control group (8.1%). This difference was statistically significant (p=0.032).

Conclusions

Based on the positive impact by ICG-FA on the AL rate, we established the ICG-FA into our clinical routine. Although randomized studies are still missing, ICG-FA can raise patient safety, with only about 10 min longer operating time and almost no additional risk for the patients.

Colonic perfusion assessment with indocyanine-green fluorescence imaging in anterior resections: a propensity score-matched analysis

BACKGROUND

Colonic perfusion is crucial for anastomotic healing and this could be evaluated intraoperatively using indocyanine-green fluorescence imaging (ICG FI). The aim of this study was to ascertain whether the use of ICG FI resulted in the reduction of anastomotic complications, i.e. AL and anastomotic stricture.

METHODS

Consecutive patients who underwent anterior resections or low anterior resections at our institution in the period from January 1st 2013 to December 31st 2018 were retrospectively reviewed. Surgery performed during the period from January 1st 2013 to December 31st 2015 did not involve the use of ICG FI (ICG-) while surgery during the period from January 1st 2016 to December 31st 2018 was performed with the use of ICG FI (ICG+). The anastomotic leakage rates of the two groups were compared after propensity score matching, taking into account the height of the anastomosis and any history of pelvic irradiation.

RESULTS

There was a total of 258 and 317 patients who had surgery with and without ICG FI, respectively. There were 253 patients in each group after propensity score matching. The overall anastomotic leakage rate was 3.6% and 7.9% for ICG+ and ICG-, respectively, (p = 0.035). Subgroup analysis showed that the use of ICG FI was significantly associated with a lower anastomotic leakage rate in total mesorectal excision (TME), 4.7% versus 11.6%, p = 0.043, but not in non-TME resections, 3.5% versus 2.4%, (p = 0.612). ICG FI, together with sex and anastomotic height, were independent predictors of anastomotic leakage.

CONCLUSIONS

The routine use of ICG FI was associated with a lower anastomotic leakage rate in anterior resections. The reduction in anastomotic leakage rate was mainly seen in TME.

Prospective Study Comparing Clinical vs Indocyanine Green Fluorescence-Based Assessment of Line of Transection in Robotic Rectal Cancer Surgery-Indian Study

Anastomotic leakage continues to be the most feared postoperative complications in rectal surgery with negative impact on both short- and long-term outcomes. Fortunately, new surgical strategies have helped to offset this complication and improve surgical outcomes. Traditionally, perfusion is assessed by intraoperative visual judgment by the surgeon. These subjective methods lack predictive accuracy resulting in either excess or insufficient colonic resection. Indocyanine green (ICG) fluorescence has shown promise in identifying the adequacy of perfusion. After injection of ICG, the system projected high-resolution near-infrared real-time images of blood flow in mesentery and bowel wall. This novel imaging method is used intraoperatively for taking real-time informed decisions. We conducted a single institutional prospective study to identify the feasibility of ICG identification of vascularity of anastomotic site and its impact on the change of plan of surgical management in robotic rectal cancer surgery. Between September 2017 and April 2019, fifty patients undergoing robotic rectal cancer surgery were included in the study. The aim was to analyze the feasibility and clinical benefit of intraoperative near-infrared fluorescence imaging in determining the line of transection in comparison with the traditional method. Line of proximal transection of the bowel subjectively assessed by the surgical team was marked point B and that after ICG injection was marked point A if moved proximally and point C if moved distally. The vascular anatomy was clearly identified with no intraoperative or injection-related adverse effects. Of the 50 patients, the line of transaction remained the same in 6 patients (12%). Based on the fluorescence imaging, the surgical team opted for further proximal change of the transection line up to an "adequate" fluorescent portion in 3 patients (6%) and distally in 41 patients (82%). ICG-based infrared image-guided localization gives a real-time image of colon vascularity possibly affecting anastomotic leak. The ICG fluorescence imaging system is a simple, safe, and useful technique, performed within a short time, and it enables visual evaluation of the blood flow in the intestinal tract prior to anastomosis. Larger studies are needed before this can become the standard of care.

Fluorescence Image-Based Evaluation of Gastric Tube Perfusion during Esophagogastrostomy

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

A prospective study of real-time identification of line of transection in robotic colorectal cancer surgery by ICG

Colorectal cancer is the second most common cancer in women and the third most common cancer in men in the world. Surgical resection is the gold standard treatment and minimally invasive surgery remains the standard of care. Anastomotic leakage is one of the most feared postoperative complications in colorectal surgery. Although several factors have been identified as possible causes of anastomotic leakage (i.e., surgical techniques, patient risk factors, suture material or devices), the complete pathogenesis is still unclear. The reported leak rate ranges from 1 to 30% and increases as the anastomosis is more distal. To date the most widely used methods to assess tissue perfusion includes the surgeon intraoperative visual judgement based on the colour; bleeding edges of resected margins; pulsation and temperature, thereby resulting in either excess or insufficient colonic resection. Earlier studies in colorectal surgery have suggested that assessment of tissue perfusion by the clinical judgment of the operating surgeon underestimated the risk of anastomotic leakage. Indocyanine green (ICG) is a intravenous dye which has shown promise in identifying the bowel vascularity real time. Earlier studies on colorectal cancer have shown that ICG based detection of bowel vascularity is technically possible and has reduced the anastomotic leak rates in 16.7% of patients. We conducted a prospective study on patients with ICG guided bowel perfusion during robotic colorectal cancer surgery. The method is technically easy, reproducible and safe. This technique has changed the intraoperative decision in 88% of patients. Larger studies are needed before this can become the standard of care.

Clinical efficacy of bowel perfusion assessment during laparoscopic colorectal resection using laser speckle contrast imaging: A matched case-control study

INTRODUCTION

Disadvantages of bowel perfusion assessment with indocyanine green fluorescence angiography include the need for a fluorophore and the subjective nature of the assessment. This study was performed to evaluate the clinical efficacy of bowel perfusion assessment using laser speckle contrast imaging (LSCI) during laparoscopic colorectal surgery.

METHODS

The study population comprised the first 27 consecutive patients who underwent laparoscopic left-sided colorectal resection with intraoperative perfusion assessment using LSCI. The operative outcomes of these patients were compared with those of a matched group of patients without perfusion assessment. We analyzed the flux data expressed in laser speckle perfusion units.

RESULTS

After propensity score matching, we found no significant between-group differences in the patients' characteristics with the exception of the cancer stage. No patients undergoing LSCI perfusion assessment developed anastomotic leakage, but five (18.5%) patients in the control group did, at a significantly higher rate in male patients (P = .042). There were no significant differences in other operative outcomes. The laser speckle perfusion unit values after ligating marginal vessels were significantly lower than before ligation (P < .01).

CONCLUSIONS

With respect to anastomotic leakage, LSCI may improve patient outcomes after colorectal surgery. This technique appears to be a superior tool with the advantages of measurement repeatability and quantitativity and no need for a fluorophore.

Indocyanine green fluorescence angiography to evaluate anastomotic perfusion in colorectal surgery

BACKGROUND

The aim of this study was to evaluate the efficacy of indocyanine green (ICG) fluorescence angiography with respect to the anastomotic leakage rate for patients undergoing colorectal operations.

METHODS

This prospective cohort involved patients who underwent colorectal surgery between August 2018 and September 2019. ICG was injected after colonic transection. Vascular perfusion was observed by ICG fluorescence system before completing anastomosis. Data was compared with those by subjective visual evaluation. The primary outcome was anastomotic leakage rate within 30 days from surgery.

RESULTS

A total of 131 patients were enrolled, of which ICG was injected in 63 of them. Demographic data were similar between the two groups. There were two (3.23%) and three (4.35%) anastomotic leaks in the ICG and non-ICG group respectively (p = 1.000). Change of resection plane occurred in one patient in the ICG group. There was no ICG related toxicity or adverse events.

CONCLUSION

ICG fluorescent imaging is a feasible and safe tool to assess colonic vascularisation for patients undergoing colorectal surgery. However, it did not significantly lower the anastomotic leakage rate. ICG should not be routinely used in colorectal surgery before an available large scale randomised controlled trial to prove any clinical benefits.

Higher modified Glasgow Prognostic Score and multiple stapler firings for rectal transection are risk factors for anastomotic leakage after low anterior resection in rectal cancer

OBJECTIVE

Anastomotic leakage (AL) is one of the most devastating complications of rectal cancer surgery. Not only does AL result in reduced quality of life, extended hospitalization and impaired defecatory function, it also has a high local recurrence rate. In this study, we investigated risk factors for AL as it may help to decrease its occurrence and improve patient outcomes.

METHODS

This study was a retrospective, single-institution study of rectal cancer patients who underwent elective low anterior resection between April 2002 and February 2018 at Fukushima Medical University Hospital. Patients were divided into two groups according to the presence of AL. Patient-, tumor-, and surgery-related variables were examined using univariate and multivariate analyses.

RESULTS

One hundred sixty-one patients, average age 63.5±11.5 years, were enrolled in the study. The overall AL rate was 6.8% (11/161). In the univariate analysis, modified Glasgow Prognostic Score (mGPS)=2 (p=0.003), use of multiple staplers (≥3 firings) for rectal transection (p=0.001) and intraoperative bleeding (≥250 g) were significantly associated with AL incidence. Multivariate analysis identified that mGPS = 2 (odds ratio [OR]: 19.6, 95% confidence interval [CI]: 2.96-125.00, p=0.002) and multiple firings (OR: 18.19, CI: 2.31-111.11, p=0.002) were independent risk factors for AL.

CONCLUSION

Higher mGPS score and multiple firings were independent risk factors for AL.

Safety and effectiveness of high ligation of the inferior mesenteric artery for cancer of the descending colon under indocyanine green fluorescence imaging: a pilot study

BACKGROUND

Complete mesocolic excision with central vascular ligation is a standard advanced technique for achieving favorable long-term oncological outcomes in colon cancer surgery. Clinical evidence abounds demonstrating the safety of high ligation of the inferior mesenteric artery (IMA) for sigmoid colon cancer but is scarce for descending colon cancer. A major concern is the blood supply to the remnant distal sigmoid colon, especially for cases with a long sigmoid colon. We sought to clarify the safety and feasibility of high ligation of the IMA in surgery for descending colon cancer using indocyanine green (ICG) fluorescence imaging.

METHODS

In this prospective single-center pilot study, we examined 20 patients with descending colon cancer who underwent laparoscopic colectomy between April 2018 and September 2019. Following full mobilization and division of the proximal colonic mesentery, we temporarily clamped the root of the IMA and performed ICG fluorescence imaging of the blood flow to the sigmoid colon. The postoperative anastomosis-related complications (primary endpoint) and length of viable remnant colon, and the number of lymph nodes retrieved (secondary endpoints) were evaluated and compared with historical controls who underwent conventional IMA-preserving surgery (n = 20).

RESULTS

Blood flow reached 40 (17-66) cm retrograde from the peritoneal reflection, even after IMA clamping. Accordingly, IMA high ligation was performed in all cases. No anastomotic anastomosis-related complications occurred in each group. Retrieved total lymph nodes were higher in number in the ICG-guided group than in the conventional group (p = 0.035). Specifically, more principal nodes were retrieved in the ICG-guided group, compared with the conventional group (p = 0.023). However, the distal margin was not as long compared with the conventional group.

CONCLUSION

We demonstrated the safety and feasibility of high ligation of the IMA for descending colon cancer without sacrificing additional distal colon using fluorescence evaluation of blood flow in the remnant colon.