Indocyanine green-enhanced fluorescence to assess bowel perfusion during laparoscopic colorectal resection. Surg Endosc. 2016;30:2736-2742. [PMID: 26487209 PMCID: PMC4912584 DOI: 10.1007/s00464-015-4540-z]

Indocyanine Green Fluorescence Imaging-Guided Laparoscopic Surgery Could Achieve Radical D3 Dissection in Patients With Advanced Right-Sided Colon Cancer

BACKGROUND

The optimal lymph node dissection with central vascular ligation is an important part for oncological outcomes after laparoscopic right-sided colon cancer surgery. Few studies have examined the clinical value of indocyanine green fluorescence imaging-guided D3 dissection for right-sided colon cancer.

OBJECTIVES

We assessed the clinical value of indocyanine green fluorescence imaging-guided laparoscopic surgery in improving the radicality of lymph node dissection for right-sided colon cancer by comparing the outcomes of conventional laparoscopic surgery.

DESIGN

The data were retrospectively reviewed and analyzed.

SETTING

This study was conducted at a single university hospital.

PATIENTS

A 1:2 matched case-control study included 25 patients undergoing fluorescence imaging-guided laparoscopic surgery and 50 patients undergoing conventional laparoscopic surgery for clinical T3 or T4 right-sided colon cancer between June 2016 and December 2017.

MAIN OUTCOME MEASURES

The extent of D3 dissection and pathological results (tumor stage, lymph node yield, and number of metastatic lymph nodes) were analyzed.

RESULTS

The 2 groups were similar in baseline characteristics. The numbers of harvested pericolic and intermediate lymph nodes were not different between the 2 groups. The numbers of central lymph nodes (14 vs 7, p < 0.001) and total harvested lymph nodes (39 vs 30, p = 0.003) were significantly higher in the fluorescence group than in the conventional group. In the multivariate analysis, the use of indocyanine green fluorescence imaging was an independently related factor for the retrieval of higher numbers of overall and central lymph nodes. The number of metastatic lymph nodes was not significantly different between the 2 groups.

LIMITATIONS

The results of this study were limited by its small patient numbers and retrospective nature.

CONCLUSIONS

Real-time indocyanine green fluorescence imaging of lymph nodes may improve the performance of more radical D3 lymph node dissection during laparoscopic right hemicolectomy for advanced right-sided colon cancer. See Video Abstract at http://links.lww.com/DCR/B150. LA CIRUGÍA LAPAROSCÓPICA GUIADA POR IMÁGENES DE FLUORESCENCIA VERDE INDOCIANINA PODRÍA LOGRAR UNA DISECCIÓN RADICAL D3 EN PACIENTES CON CÁNCER DE COLON AVANZADO DEL LADO DERECHO: La disección óptima de los ganglios linfáticos con ligadura vascular central es una parte importante para los resultados oncológicos después de la cirugía laparoscópica de cáncer de colon del lado derecho. Pocos estudios han examinado el valor clínico de la disección D3 guiada por imágenes de fluorescencia verde indocianina para el cáncer de colon del lado derecho.Evaluamos el valor clínico de la cirugía laparoscópica guiada por imagen de fluorescencia verde indocianina para mejorar la radicalidad de la disección de ganglios linfáticos para el cáncer de colon del lado derecho mediante la comparación de los resultados de la cirugía laparoscópica convencional.Los datos se revisaron y analizaron retrospectivamente.Este estudio se realizó en un solo hospital universitario.Un estudio de casos y controles emparejado 1:2 incluyó a 25 pacientes sometidos a cirugía laparoscópica guiada por imágenes de fluorescencia y 50 pacientes sometidos a cirugía laparoscópica convencional para cáncer de colon derecho clínico T3 o T4 entre Junio de 2016 y Diciembre de 2017.Se analizó el alcance de la disección D3 y los resultados patológicos (estadio tumoral, rendimiento de los ganglios linfáticos y número de ganglios linfáticos metastásicos).Los dos grupos fueron similares en las características basicas. El número de ganglios linfáticos pericólicos e intermedios recolectados no fue diferente entre los dos grupos. El número de ganglios linfáticos centrales (14 vs 7, p < 0.001) y el total de ganglios linfáticos recolectados (39 vs 30, p = 0.003) fueron significativamente mayores en el grupo de fluorescencia que en el grupo convencional. En el análisis multivariante, el uso de imágenes de fluorescencia verde indocianina fue un factor independiente relacionado para la recuperación de un mayor número de ganglios linfáticos centrales y globales. El número de ganglios linfáticos metastásicos no fue significativamente diferente entre los dos grupos.Los resultados de este estudio fueron limitados por su pequeño número de pacientes y su naturaleza retrospectiva.Las imágenes de fluorescencia verde indocianina en tiempo real de los ganglios linfáticos pueden mejorar el rendimiento de la disección más radical de los ganglios linfáticos D3 durante la hemicolectomía derecha laparoscópica para el cáncer de colon avanzado del lado derecho. Consulte Video Resumen en http://links.lww.com/DCR/B150.

Efficacy of indocyanine green fluorescence angiography in preventing anastomotic leakage after laparoscopic colorectal cancer surgery

PURPOSE

Some recent studies have suggested that fluorescence angiography with indocyanine green (ICG) might be useful for preventing anastomotic leakage (AL) after laparoscopic colorectal surgery. However, its efficacy has not been proven. We evaluated whether intraoperative ICG fluorescence angiography could decrease the AL rate with laparoscopic colorectal cancer surgery.

METHODS

This retrospective study included patients with colorectal cancer who underwent laparoscopic surgery at our institution between March 2014 and December 2018. Patients were divided into two groups: with or without ICG fluorescence angiography. The primary outcome was the rate of AL.

RESULTS

A total of 488 patients were included: 223 patients in the ICG group and 265 patients in the no-ICG group. In the ICG group, the transection line was changed to a more proximal location in seven patients (3.1%), including one patient with transverse colon surgery and six with rectal surgery. None of these seven patients developed AL. There were 18 ALs (3.7%) overall. The AL rate was 1.8% in the ICG group and 5.3% in the no-ICG group. For colon cancer, there were no significant differences in the AL rate between the groups (p = 0.278). In rectal cancer, the AL rate was significantly lower in the ICG group than in the no-ICG group (3.5% vs. 10.5%, p = 0.041). After propensity score matching, the AL rate was also significantly lower in the ICG group for rectal cancer (p = 0.044).

CONCLUSION

ICG fluorescence angiography can potentially reduce the AL rate with laparoscopic rectal cancer surgery.

Image-Guided Pediatric Surgery Using Indocyanine Green (ICG) Fluorescence in Laparoscopic and Robotic Surgery

Background: Indocyanine green (ICG)-guided near-infrared fluorescence (NIRF) has been recently adopted in pediatric minimally invasive surgery (MIS). This study aimed to report our experience with ICG-guided NIRF in pediatric laparoscopy and robotics and evaluate its usefulness and technique of application in different pediatric pathologies. Methods: ICG technology was adopted in 76 laparoscopic and/or robotic procedures accomplished in a single division of pediatric surgery over a 24-month period (January 2018-2020): 40 (37 laparoscopic, three robotic) left varicocelectomies with intra-operative lymphography; 13 (10 laparoscopic, three robotic) renal procedures: seven partial nephrectomies, three nephrectomies, and three renal cyst deroofings; 12 laparoscopic cholecystectomies; five robotic tumor excisions; three laparoscopic abdominal lymphoma excisions; three thoracoscopic procedures: two lobectomies and one lymph node biopsy for suspected lymphoma. The ICG solution was administered into a peripheral vein in all indications except for varicocele and lymphoma in which it was, respectively, injected into the testis body or the target organ. Regarding the timing of the administration, the ICG solution was administered intra-operatively in all indications except for cholecystectomy in which the ICG injection was performed 15-18 h before surgery. Results: No conversions to open or laparoscopy occurred. No adverse and allergic reactions to ICG or other postoperative complications were reported. Conclusions: Based upon our 2 year experience, we believe that ICG-guided NIRF is a very useful tool in pediatric MIS to perform a true imaged-guided surgery, allowing an easier identification of anatomic structures and an easier surgical performance in difficult cases. The most common applications in pediatric surgery include varicocele repair, difficult cholecystectomy, partial nephrectomy, lymphoma, and tumors excision but further indications will be soon discovered. ICG-enhanced fluorescence was technically easy to apply and safe for the patient reporting no adverse reactions to the product. The main limitation is represented by the specific equipment needed to apply ICG-guided NIRF in laparoscopic procedures, that is not available in all centers whereas the ICG system Firefly® is already integrated into the robotic platform.

The problem of colorectal anastomosis safety

INTRODUCTION

Anastomotic leakage (AL) remains one of the most threatening complications in colorectal surgery with the incidence of up to 20%. The aim of the study is to evaluate the safety and feasibility of novel - trimodal intraoperative colorectal anastomosis testing technique.

METHODS AND ANALYSIS

This multi-center prospective cohort pilot study will include patients undergoing colorectal anastomosis formation below 15 cm from the anal verge. Trimodal anastomosis testing will include testing for blood supply by ICG fluorescence trans-abdominally and trans-anally, testing of mechanical integrity of anastomosis by air-leak and methylene blue leak tests and testing for tension. The primary outcome of the study will be AL rate at day 60. The secondary outcomes will include: the frequency of changed location of bowel resection; ileostomy rate; the rate of intraoperative AL; time, taken to perform trimodal anastomosis testing; postoperative morbidity and mortality; quality of life.

DISCUSSION

Trimodal testing of colorectal anastomosis may be a novel and comprehensive way to investigate colorectal anastomosis and to reveal insufficient blood supply and integrity defects intraoperatively. Thus, prevention of these two most common causes of AL may lead to decreased rate of leakage.

STUDY REGISTRATION

Clinicaltrials.gov (https://clinicaltrials.gov/): NCT03958500, May, 2019.

Intraoperative angiography with indocyanine green to assess anastomosis perfusion in patients undergoing laparoscopic colorectal resection: results of a multicenter randomized controlled trial

BACKGROUND

Insufficient vascular supply is one of the main causes of anastomotic leak in colorectal surgery. Intraoperative indocyanine-green (ICG) angiography has been shown to provide information on tissue perfusion, identifying a well-perfused location for colonic and rectal transections, and thus possibly reducing the leak rate. Aim of this study was to evaluate the usefulness of intraoperative assessment of anastomotic perfusion using ICG angiography in patients undergoing left-sided colon or rectal resection with colorectal anastomosis.

METHODS

This randomized trial involved 252 patients undergoing laparoscopic left-sided colon and rectal resection randomized 1:1 to intraoperative ICG or to subjective visual evaluation of the bowel perfusion without ICG. The primary aim was to assess whether ICG angiography could lead to a reduction in anastomotic leak rate. Secondary outcomes were possible changes in the surgical strategy and postoperative morbidity.

RESULTS

After randomization, 12 patients were excluded. Accordingly, 240 patients were included in the analysis; 118 were in the study group, and 122 in the control group. ICG angiography showed insufficient perfusion of the colic stump, which led to extended bowel resection in 13 cases (11%). An anastomotic leak developed in 11 patients (9%) in the control group and in 6 patients (5%) in the study group (p = n.s.).

CONCLUSIONS

Intraoperative ICG fluorescent angiography can effectively assess vascularization of the colic stump and anastomosis in patients undergoing colorectal resection. This method led to further proximal bowel resection in 13 cases, however, there was no statistically significant reduction of anastomotic leak rate in the ICG arm.

CLINICAL TRIAL

ClinicalTrials.gov NCT02662946.

Surgical management of locally-advanced and metastatic hepatoblastoma

Advanced stage hepatoblastoma, including both locally advanced primary tumors as well as metastatic disease, poses unique clinical challenges. Despite substantial advances in chemotherapeutics, surgical extirpation remains the mainstay of cure for this tumor. Locally advanced tumors that involve multiple hepatic lobes and/or invade significant vascular structures can be managed either by complex hepatic resections or liver transplantation. We review the indications, roles, and outcomes of these surgical approaches as well as those for the resection of pulmonary metastases.

Does intra-operative flexible endoscopy reduce anastomotic complications following left-sided colonic resections? A systematic review and meta-analysis

AIM

Postoperative anastomotic leakage (AL) or bleeding (AB) significantly impacts on patient outcome following colorectal resection. To minimize such complications, surgeons can utilize different techniques perioperatively to assess anastomotic integrity. We aim to assess published anastomotic complication rates following left-sided colonic resection, comparing the use of intra-operative flexible endoscopy (FE) against conventional tests used to assess anastomotic integrity.

METHODS

PubMed/MEDLINE and Embase online databases were searched for non-randomized and randomized case-control studies that investigated postoperative AL and/or AB rates in left-sided colonic resections, comparing intra-operative FE against conventional tests. Data from eligible studies were pooled, and a meta-analysis using Review Manager 5.3 software was performed to assess for differences in AL and AB rates.

RESULTS

Data from six studies were analysed to assess the impact of FE on postoperative AL and AB rates (1084 and 751 patients respectively). Use of FE was associated with reduced postoperative AL and AB rates, from 6.9% to 3.5% and 5.8% to 2.4% respectively. Odds ratios favoured intra-operative FE: 0.37 (95% CI 0.21-0.68, P = 0.001) for AL and 0.35 (95% CI 0.15-0.82, P = 0.02) for AB.

CONCLUSION

This meta-analysis showed that the use of intra-operative FE is associated with a reduced rate of postoperative AL and AB, compared to conventional anastomotic testing methods.

Real-time indocyanine green fluorescent angiography in laparoscopic sigmoid vaginoplasty to assess perfusion of the pedicled sigmoid segment

OBJECTIVE

To assess the feasibility of intraoperative use of indocyanine green (ICG) fluorescent angiography in laparoscopic intestinal vaginoplasty to determine intestinal segment perfusion and viability.

DESIGN

Intestinal vaginoplasty may be performed as a vaginal (re)construction procedure. During surgery, a pedicled intestinal segment is transferred caudally to line the neovaginal cavity. Most commonly, a sigmoid or ileal segment is used. In obtaining adequate mobility of the segment, arterial structures sometimes have to be sacrificed, with possible detrimental effects on segment perfusion and subsequently viability. ICG may be used as an aid to assess segment perfusion. We present a case series of six consecutive patients who underwent intestinal vaginoplasty with intraoperative use of ICG.

SETTING

Tertiary university hospital.

PATIENT(S)

Six transgender women undergoing laparoscopic sigmoid vaginoplasty with intraoperative use of ICG from October 2017 to October 2018.

INTERVENTION(S)

Intraoperative use of ICG in laparoscopic sigmoid vaginoplasty to determine sigmoid segment perfusion and viability.

MAIN OUTCOME MEASURE(S)

Value and feasibility of ICG in this reconstructive procedure.

RESULT(S)

Intraoperative use of ICG demonstrated segment viability in five patients. In one patient, vascularization of the segment was deemed to be inadequate and reconstruction was aborted.

CONCLUSIONS

ICG fluorescent angiography may be used intraoperatively to assess perfusion of the pedicled sigmoid segment during sigmoid vaginoplasty.

Factors affecting the morbidity and mortality of diverting stoma closure: retrospective cohort analysis of twelve-year period

Background Diverting stoma is often performed in rectal cancer surgery for reducing the consequences of possible anastomotic failure. Closing of stoma follows in most cases after a few months. The aim of our study was to evaluate morbidity and mortality after diverting stoma closure and to identify risk factors for complications of this procedure. Patients and methods At our department, we have performed a retrospective cohort analysis of data for 260 patients with diverting stoma closure from 2003 to 2015. Age, stoma type, patient's preoperative ASA score, surgical technique and time to stoma closure were investigated as factors which could influence the complication rate. Results 218 patients were eligible for investigation. Postoperative complications developed in 54 patients (24.8%). Most common complications were postoperative ileus (10%) and wound infection (5%). Four patients died (1.8%). There was no effect on complication rate regarding type of stoma, closing technique, patient's ASA status and patient age. The only factor influencing the complication rate was the time to stoma closure. We found that patients which had the stoma closed prior to 8 months after primary surgery had lower overall complication rate (p<0. 05). Conclusions To reduce overall complication rate, our data suggest a shorter period than 8 months after primary surgery before closure of diverting stoma. As diverting stoma closure is not a simple operation, all strategies should be taken to reduce significant morbidity and mortality rate.

Visualization and quantification of anastomotic perfusion in colorectal surgery using near-infrared fluorescence

BACKGROUND

Anastomotic leakage (AL) is one of the most troublesome complications in colorectal surgery. Recently, near-infrared fluorescence (NIRF) imaging has been used intraoperatively to detect sentinel lymph nodes and visualize the blood supply at the region of interest (ROI). The aim of this study was to evaluate the role of visualization and quantification of bowel perfusion around the anastomosis using NIRF system in predicting AL.

METHODS

A prospective study was conducted on patients who had laparoscopic surgery for colorectal cancer at our institution. Perfusion of the anastomosis was evaluated with NIRF imaging after intravenous injection of indocyanine green (ICG). The time course of fluorescence intensity was recorded by an imaging analyzer We measured the time from ICG injection to the beginning of fluorescence (T₀), maximum intensity (I_max), time to reach I_max (T_max), time to reach I_max 50% ([Formula: see text]) and slope (S) after the anastomosis.

RESULTS

Tumor locations were as follows; cecum: 2, ascending colon: 2, transverse colon: 7, descending colon: 1, sigmoid colon: 2, rectosigmoid colon: 3 and rectum: 6 (one case with synchronous cancer). All operations were performed laparoscopically. Four patients were diagnosed with or suspected to have AL (2 patients with grade B anastomotic leakage after low anterior resection, 1 patient with minor leakage in transverse colon resection and 1 patient needing re-anastomosis intraoperatively in transverse colon resection). T₀ was significantly longer in the AL group than in patients without AL (64.3 ± 27.6 and 18.2 ± 6.6 s, p = 2.2 × 10^-3).

CONCLUSIONS

Perfusion of the anastomosis could be successfully visualized and quantified using NIRF imaging with ICG. T₀ might be a useful parameter for prediction of AL.

Safety and feasibility of repeat laparoscopic colorectal resection: a matched case-control study

BACKGROUND

Perioperative outcomes of repeat laparoscopic colorectal resection (LCRR) have not been extensively reported.

METHODS

Patients who underwent LCRR from 2010 to 2018 in an expert center were retrieved from a prospectively collected database and compared to 2:1 matched sample. Matching was based on demographics, surgical indication [colorectal cancer (CRC) or benign condition], and type of resection (right-sided resection or left-sided resection or proctectomy).

RESULTS

Twenty-three patients underwent repeat LCRR with a median time of 36 months between the primary and the repeat LCRR. They were 12 (52%) men with a mean age of 64.9 years (31-87) and a median BMI of 21.4 kg/m² (17.7-34). Indication for repeat LCRR was CRC, dysplasia, anastomotic stricture, and inflammatory bowel disease in 11 (48%), 5 (22%), 4 (17%), and 3 (13%) patients, respectively. A right-sided resection, a left-sided resection, and proctectomy were reported in 11 (48%), 8 (35%), and 4 (17%) patients, respectively. Median blood loss reached 211 mL (range 0-2000 mL). Thirteen (57%) patients required conversion to laparotomy including 12 for intense adhesions. The median length of hospital stay was 7.5 days (5-20). Two (9%) major complications (Clavien-Dindo ≥ 3) were reported: 1 (4%) anastomotic fistula and 1 (4%) postoperative hemorrhage, without mortality. Among patients who underwent repeat LCRR for CRC, histopathological examination showed R0 resection in all patients, with at least 12 lymph nodes harvested in ten (91%) patients. After matched case-control analysis that compared to primary LCRR, conversion rate (p = 0.03), operative time (p = 0.03), and intraoperative blood loss (p = 0.0016) were significantly increased in repeat LCRR, without impact on postoperative outcomes.

CONCLUSIONS

Repeat LCRR seems to be feasible and safe in expert hands without compromising the oncologic outcomes. Intense postoperative adhesions and misidentification of blood supply might lead to conversion to laparotomy. Real benefits of laparoscopic approach for repeat LCRR should be assessed in further studies.

Assessment of Anastomotic Perfusion in Left-Sided Robotic Assisted Colorectal Resection by Indocyanine Green Fluorescence Angiography

Background

Indocyanine green fluorescent angiography (IcGA) has been used with success in guiding intraoperative management to prevent colorectal anastomotic complications. Prior studies in open and laparoscopic colorectal surgery, such as PILLAR II, have demonstrated a low anastomotic leak rate (1.4%). As the minimally invasive approach progresses from laparoscopic to robotic approach, the effect and safety of IcGA in assessing anastomotic perfusion in the latter deserve further investigation.

Methods

The objective of the study was to determine the safety of IcGA in guiding intraoperative management of robotic assisted colorectal resection via perfusion assessment. The design was single-surgeon, retrospective case-control study. 74 patients underwent left-sided robotic assisted colorectal resection and anastomosis with IcGA guidance. 30 historical controls underwent left-sided robotic assisted colorectal resection and anastomosis without IcGA. Clinical, demographic, operative, and outcome variables were tabulated.

Results

In the control group, 1 patient suffered a postoperative anastomotic stricture requiring no surgery, and 1 patient suffered an anastomotic dehiscence requiring return to the operating room. There were no anastomotic complications in the IcGA group, including 4 patients who underwent a change in the chosen level of anastomosis based on intraoperative IcGA.

Conclusion

IcGA is safe to use as demonstrated by the very low rate of complications in this case series. It is also safe to rely on to guide re-resection and recreation of an anastomosis intraoperatively by demonstration of blood flow. This may help offset the loss of tactile feedback and assessment of tension in the robotic platform.

Technical Note: Are Currently Used Measurements of Fluorescence Intensity in Near Infrared Fluorescence Imaging During Laparoscopic Cholecystectomy Comparable?

Aims: To investigate whether different calculation methods to express fluorescence intensity (FI) as target-to-background (BG) ratio are comparable and which method(s) match with human perception. Materials and Methods: Comparison of three calculation methods from current literature (OsiriX^®, ImageJ^®, and Photoshop^®) to objectify FI during laparoscopic cholecystectomy measured at the exact same locations within recorded images of two categories: ex vivo and in vivo. Currently applied formulas to present FI in relation to the BG signal are compared with the subjective assessment by the human observers. These three formulas are Signal contrast = (FI in fluorescence regions-FI in BG)/255; Target-to-background ratio = (FI of target-FI of BG)/FI of BG; Signal-to-background ratio = FI of cystic duct/FI of liver and Target-to-background ratio = (FI of target-noise)/(FI of BG-noise). Results: In our evaluation OsiriX and ImageJ provided similar results, whereas OsiriX values were structurally slightly lower compared with ImageJ. Values obtained through Photoshop were less evidently related to those obtained with OsiriX and ImageJ. The formula Target-to-background ratio = (FI of target-noise)/(FI of BG-noise) was less corresponding with human perception compared with the other used formulas. Conclusions: FI results based on measurements using the programs OsiriX and ImageJ are similar, allowing for comparison of results between these programs. Results using Photoshop differ significantly, making direct comparison impossible. This is an important finding when interpreting study results. We propose to report both target and BG FI in articles, so that proper interpretation between articles can be made.

Size and lipid modification determine liposomal Indocyanine green performance for tumor imaging in a model of rectal cancer

Localization of rectal tumors is a challenge in minimally invasive surgery due to the lack of tactile sensation. We had developed liposomal indocyanine green (Lip-ICG) for localization of rectal tumor. In this study we evaluated the effects of liposome size and lipid PEGylation on imaging. We used an endoscopically-guided orthotopic experimental rectal cancer model in which tumor fluorescence was determined at different time points after intravenous (i.v.) administration of Lip-ICG and PEGylated liposomes (PEG-Lip-ICG). Signal intensity was measured by tumor-to-background ratio (TBR), or normalized TBR (compared to TBR of free ICG). Fluorescence microscopy of tumor tissue was performed to determine fluorescence localization within the tissue and blood vessels. Liposomes of 60 nm showed an increased TBR compared with free ICG at 12 hours after i.v. injection: normalized TBR (nTBR) = 3.11 vs. 1, respectively (p = 0.006). Larger liposomes (100 nm and 140 nm) had comparable signal to free ICG (nTBR = 0.98 ± 0.02 and 0.78 ± 0.08, respectively), even when additional time points were examined (0.5, 3 and 24 hours). PEG-Lip- ICG were more efficient than Lip-ICG (TBR = 4.2 ± 0.18 vs. 2.5 ± 0.12, p < 0.01) presumably because of reduced uptake by the reticulo-endothelial system. ICG was found outside the capillaries in tumor margins. We conclude that size and lipid modification impact imaging intensity.

The significance of intraoperative fluorescence angiography in miniinvasive low rectal resections

Introduction

Anastomotic leak is a very serious complication in colorectal surgery. Tissue perfusion of the anastomosis plays an integral role in its multifactorial etiology. Fluorescence angiography using indocyanine green allows visualization of perfusion in real time.

Aim

To evaluate the effectiveness of intraoperative fluorescence angiography as a tool to decrease the incidence of anastomotic leak after laparoscopic or robotic low resection of the rectum for cancer.

Material and methods

Intraoperative fluorescence angiography was performed sequentially in 50 patients during low rectal resection for cancer with total mesorectal excision, primary anastomosis and protective ileostomy using laparoscopic or robotic technique. The results were compared to a historical control group of 50 patients with the same procedure without the use of fluorescence angiography.

Results

The patient sets were comparable in basic demographic and clinical parameters. Intraoperative visualization of perfusion by fluorescence angiography was achieved in all patients without unwanted side-effects. In 6 (12%) patients, the resection line was adjusted based on the fluorescence angiography. The incidence of anastomotic leak was insignificantly lower in the group with fluorescence angiography (18% vs. 10%), which led to significantly shorter hospital stay. Other postoperative complications were comparable between the two groups.

Conclusions

Fluorescence angiography using indocyanine green is a safe and effective method with the potential of reducing anastomotic leak during minimally invasive low resection of the rectum for cancer.

Complete mesocolic excision for colonic cancer

INTRODUCTION

Complete mesocolic excision for colonic cancer is similar in concept to total mesorectal excision for rectal cancer. This review aims to provide the embryological and anatomical rationale behind CME, and to review the current literature on CME, relative to the feasibility via laparoscopy, the oncological adequacy and outcomes.

EVIDENCE ACQUISITION

A literature search was performed at the end of 2017 according the PRISMA guidelines for systematic reviews. Of 3980 articles found, we analyzed 96 articles. Of note, many case series had overlapping populations; there were five review articles, two consensus conference proceedings, six comparative but only one randomized trial.

EVIDENCE SYNTHESIS

The embryonic and anatomical rationale is well described. CME is feasible via laparoscopy, which may facilitate dissection and anatomic precision: no statistically significant differences were found when compared to open CME regarding overall survival. However, morbidity may be higher in the hands of non-expert laparoscopic surgeons.

CONCLUSIONS

Oncological adequacy can be obtained with laparoscopic CME, with increased lymph node retrieval. However, until now, there is no formal proof that CME improves local recurrence or survival.

Clarification of the resection line non-intubated segmentectomy using indocyanine green

A reflection on the measure of fluorescence specificity of indocyanine green (ICG) in non-intubated pulmonary segmentectomy.

Pylorus-preserving pancreatoduodenectomy preserving the right gastroepiploic vessels following proximal gastrectomy: report of two cases

BACKGROUND

Blood flow of the remnant stomach is supplied via the right gastric and right gastroepiploic vessels after proximal gastrectomy (PG). Whether the remnant stomach can be safely preserved in patients who undergo pylorus-preserving pancreatoduodenectomy (PPPD) after PG remains unclear. We herein report two cases in which the remnant stomach was safely preserved by performing PPPD.

CASE PRESENTATION

The first patient, a 76-year-old man, was diagnosed with cancer of the common bile duct and underwent PPPD 2 years after PG for gastric cancer. The remnant stomach and right gastroepiploic vessels were safely preserved. The second patient, a 56-year-old man with a history of PG for gastric cancer 20 years previously, was diagnosed with cancer of the common bile duct and underwent PPPD. We could safely preserve the remnant stomach and right gastroepiploic vessels.

CONCLUSION

The remnant stomach could be preserved in performing PPPD following PG by preserving the right gastroepiploic vessels.

Near-infrared fluorescence image-guidance in anastomotic colorectal cancer surgery and its relation to serum markers of anastomotic leakage: a clinical pilot study

OBJECTIVE

Near-infrared fluorescence (NIRF) imaging using indocyanine green (ICG) might help reduce anastomotic leakage (AL) after colorectal surgery. This pilot study aims to analyze whether a relation exists between measured fluorescence intensity (FI) and postoperative inflammatory markers of AL, C-reactive protein (CRP), Intestinal fatty-acid binding protein (I-FABP), and calprotectin, to AL, in order to evaluate the potential of FI to objectively predict AL.

METHODS

Patients scheduled for anastomotic colorectal cancer surgery were eligible for inclusion in this prospective pilot study. During surgery, at three time points (after bowel devascularization; before actual transection; after completion of anastomosis) a bolus of 0.2 mg/kg ICG was administered intravenously for assessment of bowel perfusion. FI was scored in scale from 1 to 5 based on the operating surgeon's judgment (1 = no fluorescence visible, 5 = maximum fluorescent signal). The complete surgical procedure was digitally recorded. These recordings were used to measure FI postoperatively using OsiriX imaging software. Serum CRP, I-FABP, and calprotectin values were determined before surgery and on day 1, 3, and 5 postoperative; furthermore, the occurrence of AL was recorded.

RESULTS

Thirty patients (n = 19 males; mean age 67 years; mean BMI 27.2) undergoing either laparoscopic or robotic anastomotic colorectal surgery were included. Indication for surgery was rectal-(n = 10), rectosigmoid-(n = 2), sigmoid-(n = 10), or more proximal colon carcinomas (n = 8). Five patients (16.7%) developed AL (n = 2 (6.6%) grade C according to the definition of the International Study group of Rectal Cancer). In patients with AL, the maximum fluorescence score was given less often (P = 0.02) and a lower FI compared to background FI was measured at 1st assessment (P = 0.039). However, no relation between FI and postoperative inflammatory parameters could be found.

CONCLUSION

Both subjective and measured FI seem to be related to AL. In this study, no relation between FI and inflammatory serum markers could yet be found.

Laser Speckle Contrast Imaging for Intraoperative Quantitative Assessment of Intestinal Blood Perfusion During Colorectal Surgery: A Prospective Pilot Study

BACKGROUND

The main limitation of perfusion assessment with indocyanine green fluorescence angiography during colorectal surgery is that the surgeon assesses the quality of perfusion subjectively. The ideal intestinal viability test must be minimally invasive, objective, and reproducible. We evaluated the quantitativity and reproducibility of laser speckle contrast imaging for perfusion assessment during colorectal surgery.

METHODS

This was a prospective, nonrandomized, pilot study of 8 consecutive patients who underwent elective left-sided colorectal resection. Laser speckle perfusion images at the site of proximal transection of the bowel were obtained intraoperatively. We tested the hypothesis that laser speckle contrast imaging was able to quantitatively identify areas of diminished intestinal perfusion after devascularization and assessed the reproducibility of this method.

RESULTS

All surgical procedures were uneventful and blood flow measurements were successfully made in all patients. None of the patients developed postoperative complications related to the anastomosis and stoma. Data analyses were successfully optimized to perform quantitative regional perfusion assessments in all cases. The bowel tissue blood flows of the anal side region adjacent to the transection line were significantly lower than those of the oral side region adjacent to the transection line after ligation of marginal vessels ( P = .012). Interrater reliability was high (intraclass correlation coefficients = 0.989), and a Bland-Altman plot showed few differences of mean flux data between 2 investigators.

CONCLUSION

Laser speckle contrast imaging is feasible for real-time assessment of bowel perfusion with quantitativity and excellent reproducibility during colorectal surgery without administration of any contrast agents.

Robotic-assisted stereotactic real-time navigation: initial clinical experience and feasibility for rectal cancer surgery

BACKGROUND

Real-time stereotactic navigation for transanal total mesorectal excision has been demonstrated to be feasible in small pilot series using laparoscopic techniques. The possibility of real-time stereotactic navigation coupled with robotics has not been previously explored in a clinical setting.

METHODS

After pre-clinical assessment, and configuration of a robotic-assisted navigational system, two patients with locally advanced rectal cancer were selected for enrollment into a pilot study designed to assess the feasibility of navigation coupled with the robotic da Vinci Xi platform via TilePro interface. In one case, fluorescence-guided surgery was also used as an adjunct for structure localization, with local administration of indocyanine green into the ureters and at the tumor site.

RESULTS

Each operation was successfully completed with a robotic-assisted approach; image-guided navigation provided computed accuracy of ± 4.5 to 4.6 mm. The principle limitation encountered was navigation signal dropout due to temporary loss of direct line-of-sight with the navigational system's infrared camera. Subjectively, the aid of navigation assisted the operating surgeon in identifying critical anatomical planes. The combination of fluorescence with image-guided surgery further augmented the surgeon's perception of the operative field.

CONCLUSIONS

The combination of stereotactic navigation and robotic surgery is feasible, although some limitations and technical challenges were observed. For complex surgery, the addition of navigation to robotics can improve surgical precision. This will likely represent the next step in the evolution of robotics and in the development of digital surgery.

Efficacy of Assessing Intraoperative Bowel Perfusion with Near-Infrared Camera in Laparoscopic Gastric Cancer Surgery

BACKGROUND

Anastomotic leakage is a severe complication after gastric cancer surgery. Inadequate blood supply is regarded as an important risk factor. The aim of the study was to evaluate the feasibility and usefulness of intraoperative assessment of anastomotic vascular perfusion in gastric cancer surgery using near-infrared (NIR) camera imaging with indocyanine green (ICG)-enhanced fluorescence technique.

MATERIALS AND METHODS

From March 2015 to 2016, 30 patients undergoing laparoscopic gastrectomy for gastric cancer were prospectively evaluated. After completing the anastomosis, 2.5-5.0 mg of ICG was injected via peripheral veins. All anastomoses and resection margins were investigated using NIR camera to assess anastomotic perfusion. The assessment was performed using the adopted perfusion score of fluorescence activity, which ranged from 1 to 5 (1 = no uptake, and 5 = iso-fluorescent to all other segments).

RESULTS

Twenty-six distal gastrectomy (20 gastroduodenostomies, 6 gastrojejunostomies), 3 total gastrectomies (TG), and 1 pylorus-preserving gastrectomy were performed. The gap of visualization was 4.1 ± 3.2 minutes (range, 2-15) after ICG injection. Twenty-three of 30 patients (76.7%) showed technically successful ICG visualization. Among gastroduodenostomies, the average scores for gastric and duodenal sides were 3.5 and 3.7. Among gastrojejunostomies, the average scores for gastric, jejunal, and duodenal stump sides were 3.5, 4.0, and 3.8 (jejunojejunostomy, 3.5). Among TG, the average scores for esophagojejunostomy, duodenal stump, and jejunojejunostomy were 3.7, 4.0, 4.0, and 4.7. One case of leakage occurred in this study. Other complications included fluid collection and stenosis in 1 patient each.

CONCLUSIONS

This study showed intraoperative ICG angiography using NIR camera is feasible and provides imaging of anastomotic blood flow. Further studies are needed for practice.

Risk Factors and Adequate Management for Complications of Bevacizumab Treatment Requiring Surgical Intervention in Patients With Metastatic Colorectal Cancer

BACKGROUND

Bevacizumab (BV) has been approved for treating colorectal cancer since 2004. Although BV use may lead to adverse effects, few studies have reported incidences requiring surgical intervention. We aimed to identify the risk factors and adequate interventions for complications requiring surgical intervention after BV treatment.

PATIENTS AND METHODS

We retrospectively reviewed the records of patients with metastatic colorectal cancer treated with BV in our institute from January 2009 to December 2016. The baseline patient characteristics were used to evaluate the potential risk factors for complications requiring surgery.

RESULTS

Of the 1008 patients recruited for this study, 60 (5.9%) experienced complications necessitating surgery after BV therapy. Gastrointestinal perforation was the most frequently observed complication, occurring in 36 patients (3.5%), and diverting colostomy was the most commonly performed intervention (22 patients, 36.6%). Multivariate analysis helped identify poor differentiation, signet ring cell carcinoma, stent insertion status, rectal location of the primary tumor, and intact primary tumor status as the risk factors. Survival time remained unchanged regardless of a complication that required surgery.

CONCLUSION

Careful monitoring during BV treatment for metastatic colorectal cancer is essential for patients who have a predisposition to complications that may require surgery. After detection, adequate and timely surgical management is imperative for ensuring patient survival.

A Novel Method of Damage Control for Multiple Discontinuous Intestinal Injuries with Hemorrhagic Shock: A Controlled Experiment

Aim: In this study, we examined the effects of branched silicon tube (BST) and temporary closed circle (TCC) in a Beagle dog model of multiple transection of small intestine and discontinuities suspected intestinal necrosis with hemorrhagic shock. Materials and Methods: Ten male Beagle dogs were randomly divided into two groups. Hemorrhagic shock was induced by bleeding. Intestine was severed. Suspected intestinal necrotic model by ligating the mesenteric vessels was established, with a small tertiary mesenteric vessel reserved. Fracted intestines were ligated (IL group, n = 5) or reconnected with BST (IR group, n = 5). The abdominal cavity was temporarily closed with TCC. Definitive surgery was conducted after 24 h. Results: There was no statistical difference between two groups in the weight of dogs, their blood loss, fluid resuscitation, operation time of early emergency treatment (EET). After definitive surgery, all dogs in IR group and 3 dogs in IL groups were alive. 18 (90%) suspicious necrotic intestinal segments in IL group became necrotic, but 20 (80%) segments in IR group didn't develop obvious changes (p < 0.01). From 2 h after EET, the endotoxin concentration in IL group was significantly higher than that in IR group (133.87 ± 43.73 vs. 56.31 ± 24.70 pg/ml, p < 0.01). Microscopic examination revealed that much more severe damage occurred in the suspicious necrotic intestinal segments in IL group. Conclusion: Both reconnecting intestine with BST and temporary abdominal closure with TCC are viable methods of damage control for multiple discontinuous intestinal injuries.

Indocyanine Green Fluorescence Angiography and the Incidence of Anastomotic Leak After Colorectal Resection for Colorectal Cancer: A Meta-analysis

BACKGROUND

Anastomotic leak is a life-threatening complication of colorectal surgery. Recent studies showed that indocyanine green fluorescence angiography might be a method to prevent anastomotic leak.

OBJECTIVE

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

DATA SOURCES

Potential relevant studies were identified from the following databases: PubMed, Embase, Web of Science, Cochrane Library, and China National Knowledge Infrastructure.

STUDY SELECTION

This meta-analysis included comparative studies investigating the association between indocyanine green fluorescence angiography and anastomotic leak in patients undergoing surgery for colorectal cancer where the diagnosis of anastomotic leak was confirmed by CT and the outcomes of the indocyanine green group were compared with a control group.

INTERVENTION

Indocyanine green was injected intravenously after the division of the mesentery and colon but before anastomosis.

MAIN OUTCOME MEASURES

The Newcastle-Ottawa Scale was used to assess methodologic quality of the studies. ORs and 95% CIs were used to assess the association between indocyanine green and anastomotic leak.

RESULTS

In 4 studies with a total sample size of 1177, comparing the number of anastomotic leaks in the indocyanine green and control groups, the ORs were 0.45 (95% CI, 0.18-1.12), 0.30 (95% CI, 0.03-2.98), 0.17 (95% CI, 0.01-3.69), and 0.12 (95% CI, 0.03-0.52). The combined OR was 0.27 (95% CI, 0.13-0.53). The difference was statistically significant (p < 0.001), and there was no significant heterogeneity (p = 0.48; I = 0).

LIMITATIONS

Data could not be pooled because of the small number of studies; some differences between studies may influence the results. Also, the pooled data were not randomized.

CONCLUSIONS

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

Does near-infrared (NIR) fluorescence angiography modify operative strategy during emergency procedures?

INTRODUCTION

Bowel viability can be difficult to evaluate during emergency surgery. Near-infrared (NIR) fluorescence angiography allows an intraoperative assessment of organ perfusion during elective surgery and might help to evaluate intestinal perfusion during emergency procedures. The aim of this study was to assess if NIR modified operative strategy during emergency surgery.

MATERIALS AND METHODS

From July 2014 to December 2015, we prospectively evaluated all consecutive patients, who had NIR assessment during emergency surgery. Primary endpoint was the modification of operative strategy after the assessment with NIR. Secondary endpoints were general post-operative outcomes, including reoperation rate.

RESULTS

Fifty-six patients were included in the study. Mean age was 64 ± 17 years. An exploratory laparoscopy was performed in 39% (n = 22) and an open surgery in 61% of cases (n = 34). Conversion rate to open surgery was 41% (n = 9). 32 patients had a bowel resection. In 32% of the cases (n = 18), the result of the NIR test led to a modification of the operative strategy. Among them, 33% (n = 6) had a larger resection or a resection, which was initially not planned. The other 12 patients (67%) had finally no resection, which was initially thought to be performed. Importantly, none of those patients needed a reoperation for ischemia. Mean time for performing NIR test was 167 s (± 121). Overall reoperation rate was 16.1% (n = 9). Two patients had an anastomotic leak. Eight patients (14.3%) died within the first 30 post-operative days; however, none of them presented a bowel ischemia or an anastomotic leak.

CONCLUSION

NIR is an easy and short procedure, which can be performed during emergency surgery to assess bowel perfusion. It may help the surgeon to preserve intestinal length or to define the exact limits of resection. Overall, we report a modification of operative strategy in up to one-third of evaluated patients.

Quantitative analysis of colon perfusion pattern using indocyanine green (ICG) angiography in laparoscopic colorectal surgery

Purpose

This study aimed to quantitatively evaluate colon perfusion patterns using indocyanine green (ICG) angiography to find the most reliable predictive factor of anastomotic complications after laparoscopic colorectal surgery.

Methods

Laparoscopic fluorescence imaging was applied to colorectal cancer patients (n = 86) from July 2015 to December 2017. ICG (0.25 mg/kg) was slowly injected into peripheral blood vessels, and the fluorescence intensity of colonic flow was measured sequentially, producing perfusion graphs using a video analysis and modeling tool. Colon perfusion patterns were categorized as either fast, moderate, or slow based on their fluorescence slope, T_1/2MAX and time ratio (TR = T_1/2MAX/T_MAX). Clinical factors and quantitative perfusion factors were analyzed to identify predictors for anastomotic complications.

Results

The mean age of patients was 65.4 years, and the male-to-female ratio was 63:23. Their operations were laparoscopic low anterior resection (55 cases) and anterior resection (31 cases). The incidence of anastomotic complication was 7%, including colonic necrosis (n = 1), anastomotic leak (n = 3), delayed pelvic abscess (n = 1), and delayed anastomotic dehiscence (n = 1). Based on quantitative analysis, the fluorescence slope, T_1/2MAX, and TR were related with anastomotic complications. The cut-off value of TR to categorize the perfusion pattern was determined to be 0.6, as shown by ROC curve analysis (AUC 0.929, P < 0.001). Slow perfusion (TR > 0.6) was independent factor for anastomotic complications in a logistic regression model (OR 130.84; 95% CI 6.45–2654.75; P = 0.002). Anastomotic complications were significantly correlated with the novel factor TR (> 0.6) as the most reliable predictor of perfusion and anastomotic complications.

Conclusions

Quantitative analysis of ICG perfusion patterns using T_1/2MAX and TR can be applied to detect segments with poor perfusion, thereby reducing anastomotic complications during laparoscopic colorectal surgery.

Green indocyanine fluorescence in robotic abdominal surgery

Fluorescent imaging with indocyanine green (ICG) is an emerging technology that is gaining acceptance for being a valid tool in surgeons' decision making. ICG binds to plasma lipoproteins if injected intravenously and, when excited by near-infrared light, provides anatomic information about organs vascularization and tissues perfusion. If injected in tissues, it migrates in the lymphatic system, therefore enabling the identification of lymphatic draining pathways of different organs. In this paper we address specific applications of ICG fluorescence in robotic general surgery.

The Utility of Intraoperative Near Infrared Fluorescence (NIR) Imaging with Indocyanine Green (ICG) for the Assessment of Kidney Allograft Perfusion

Background

Near infrared light (NIR) fluorescence imaging with indocyanine green (ICG) has been used in various aspects of surgery, such as in the assessment of vascular anastomosis, tissue perfusion, and the identification of lymph nodes. In this study we evaluated the utility of NIR/ICG fluorescence imaging in kidney transplantation.

Materials and Methods

NIR/ICG imaging was used to assess allograft perfusion in n=1 living donor (LDRT) and n=2 deceased donor (DDRT) renal transplantations, performed in February 2017. The allograft arterial and venous anastomoses were done end-to-side to the corresponding recipient external iliacs, and ureteroneocystostomies were performed for urinary reconstructions. After completion of vascular anastomosis, ICG was given as intravenous bolus at 0.3mg/kg, followed by visual assessment of tissue perfusion and vascular anastomoses at 1-minute interval using fluorescence imaging (KARL STORZ NIR/ICG System).

Results

Homogenous global fluorescence of the allograft and vascular anastomosis was observed in all 3 cases. Immediate postoperative perfusion studies showed patent inflow and outflow vessels and well perfused transplanted kidneys. Immediate graft function was observed in 2 recipients (1 LDRT and 1 DDRT). One session of haemodialysis was performed in 1 DDRT recipient, for high serum potassium in the immediate postoperative setting, who otherwise had good urine output and serially declining serum creatinine.

Conclusions

NIR/ICG fluorescence imaging can be useful in renal transplantation for the intraoperative assessment of allograft perfusion, especially in complex cases with multiple renal arteries and vascular reconstructions.

Colorectal surgeons should be open to modern surgical technologies for challenging cases

Today, colorectal surgeons globally are practicing in an exciting era where surgical technologies are constantly emerging. Most of these cutting-edge technologies are readily available in Australia and New Zealand at present. Thus the 'modern surgeon' should always be defined by this open-minded attitude towards these new and emerging surgical technologies. This review article highlights current modalities that we have been using in our north-Brisbane public and private hospitals for cases predicted to be technically challenging using minimally invasive approaches for most of them. We examined the current evidence regarding the following modalities and critiqued their use in clinical practice: lighted ureteric stents, minimally invasive surgery approaches of laparoscopy and robotic surgery, pressure barrier insufflation devices, 3D camera systems, hand-assist device ports and indocyanine green dye fluorescence angiography. The objective of this review paper is to alert colorectal surgeons to new surgical technologies available to them, to encourage colorectal surgeons' familiarization with these many technologies, and to support evidence-based consideration for the clinical use of such. These technologies should be supplemental aides to the safe, oncologically adequate and efficient operation that they already routinely perform.

Identification of the Thoracic Duct Using Indocyanine Green During Cervical Lymphadenectomy

BACKGROUND

Injury to the thoracic duct (TD) is the most common complication after a left lateral neck dissection, and it carries a high degree of morbidity. Currently, no routine diagnostic imaging is used to assist with TD identification intraoperatively. This report describes the first clinical experience with lymphangiography using indocyanine green (ICG) during lateral neck dissections.

METHODS

In six patients undergoing left lateral neck dissection (levels 2-4) for either thyroid cancer or melanoma, 2.5-5 mg of ICG was injected in the dorsum of the left foot 15 min before imaging. Intraoperative imaging was performed with a hand-held near infrared (NIR) camera (Hamamatsu, PDE-Neo, Hamamatsu City, Japan).

RESULTS

In five patients, the TD was visualized using NIR fluorescence, with a time of 15-90 min from injection to identification. Imaging was optimized by positioning the camera at the angle of the mandible and pointing into the space below the clavicle. No adverse reactions from the ICG injection occurred, and the time required for imaging was 5-10 min. No intraoperative TD injury was identified, and no chyle leak occurred postoperatively. For the one patient in whom the TD was not identified, it is unclear whether this was related to the timing of the injection or to duct obliteration from a prior dissection.

CONCLUSION

This is the first described application of ICG lymphangiography to identify the thoracic duct during left lateral neck dissection. Identification of TD with ICG is technically feasible, simple to perform with NIR imaging, and safe, making it a potential important adjunct for the surgeon.

Emergency Presentations of Diverticulitis

Acute diverticulitis is a common condition that has been increasing in incidence in the United States. It is associated with increasing age, but the pathophysiology of acute diverticulitis is still being elucidated. It is now believed to have a significant contribution from inflammatory processes rather than being a strictly infectious process. There are still many questions to be answered regarding the optimal management of acute diverticulitis because recent studies have challenged traditional practices, such as the routine use of antibiotics, surgical technique, and dietary restrictions for prevention of recurrence.

Assessment of Bowel End Perfusion After Mesenteric Division: Eye Versus SPY

BACKGROUND

Anastomotic complications related to tissue ischemia cause morbidity in gastrointestinal (GI) surgery. Surgeons' standard practice to predict bowel perfusion is inspection of mesenteric perfusion before anastomosing bowel ends. Augmenting this assessment with fluorescent imaging is under study. A standardized system to evaluate this imaging has not yet been developed. This study compared the surgeon's intraoperative assessment to a novel GI-specific imaging analysis method.

MATERIALS AND METHODS

Forty-nine consecutive patients undergoing open or laparoscopic-assisted bowel resections were enrolled. After mesenteric division, the surgeon marked the site for bowel transection. Near-infrared fluorescence imaging was performed on the marked bowel ends. Imaging analysis identified theoretical transection sites based on the quantification of arterial and microvascular inflow (Perfusion) and venous outflow (Timing). The primary outcome was the measured disparity between the site marked by the surgeon using current standard of care parameters and the imaging-determined site. No clinical outcomes were assessed.

RESULTS

Seventy-two bowel end segments from 46 patients were analyzed. Disparity was found in 11 of 72 (15%) bowel end segments. In five (7%), the disparity was due to either Perfusion or Timing (single), and in six (8%), due to both Perfusion and Timing (combined). In the single disparity group, the median disparity distance was 2.0 cm by Perfusion and 4.0 cm by Timing, and in the combined group, 3.8 cm by Perfusion and 3.5 cm by Timing. Disparity (either single or combined) was in 25% of colon and 11.5% of small bowel (P = NS). Combined and single disparity had equivalent lengths of disparity distance (P = NS).

CONCLUSIONS

Imaging coupled with this GI-specific analysis provides objective, real-time, and interpretable data of intramural blood supply. A 15% disparity rate from current clinical practice was observed.

A practical guide for the use of indocyanine green and methylene blue in fluorescence-guided abdominal surgery

Near-infrared (NIR) fluorescence imaging is gaining clinical acceptance over the last years and has been used for detection of lymph nodes, several tumor types, vital structures and tissue perfusion. This review focuses on NIR fluorescence imaging with indocyanine green and methylene blue for different clinical applications in abdominal surgery with an emphasis on oncology, based on a systematic literature search. Furthermore, practical information on doses, injection times, and intraoperative use are provided.

Multicentre phase II trial of near-infrared imaging in elective colorectal surgery

BACKGROUND

Decreasing anastomotic leak rates remain a major goal in colorectal surgery. Assessing intraoperative perfusion by indocyanine green (ICG) with near-infrared (NIR) visualization may assist in selection of intestinal transection level and subsequent anastomotic vascular sufficiency. This study examined the use of NIR-ICG imaging in colorectal surgery.

METHODS

This was a prospective phase II study (NCT02459405) of non-selected patients undergoing any elective colorectal operation with anastomosis over a 3-year interval in three tertiary hospitals. A standard protocol was followed to assess NIR-ICG perfusion before and after anastomosis construction in comparison with standard operator visual assessment alone.

RESULTS

Five hundred and four patients (median age 64 years, 279 men) having surgery for neoplastic (330) and benign (174) pathology were studied. Some 425 operations (85·3 per cent) were started laparoscopically, with a conversion rate of 5·9 per cent. In all, 220 patients (43·7 per cent) underwent high anterior resection or reversal of Hartmann's operation, and 90 (17·9 per cent) low anterior resection. ICG angiography was achieved in every patient, with a median interval of 29 s to visualization of the signal after injection. NIR-ICG assessment resulted in a change in the site of bowel division in 29 patients (5·8 per cent) with no subsequent leaks in these patients. Leak rates were 2·4 per cent overall (12 of 504), 2·6 per cent for colorectal anastomoses and 3 per cent for low anterior resection. When NIR-ICG imaging was used, the anastomotic leak rates were lower than those in the participating centres from over 1000 similar operations performed with identical technique but without NIR-ICG technology.

CONCLUSION

Routine NIR-ICG assessment in patients undergoing elective colorectal surgery is feasible. NIR-ICG use may change intraoperative decisions, which may lead to a reduction in anastomotic leak rates.