Near-infrared fluorescence imaging with indocyanine green for quantification of changes in tissue perfusion following revascularization, published in Vascular

Current diagnostic modalities for patients with peripheral artery disease (PAD) mainly focus on the macrovascular level. For assessment of tissue perfusion, near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) seems promising. In this prospective cohort study, ICG NIR fluorescence imaging was performed pre- and post-revascularization to assess changes in foot perfusion.

Methods: ICG NIR fluorescence imaging was performed in 36 patients with PAD pre- and post-intervention. After intravenous bolus injection of 0.1 mg/kg ICG, the camera registered the NIR fluorescence intensity over time on the dorsum of the feet for 15 min using the Quest Spectrum Platform®. Time-intensity curves were plotted for three regions of interest (ROI): (1) the dorsum of the foot, (2) the forefoot, and (3) the hallux. Time-intensity curves were normalized for maximum fluorescence intensity. Extracted parameters were the maximum slope, area under the curve (AUC) for the ingress, and the AUC for the egress. The non-treated contralateral leg was used as a control group.

Results: Successful revascularization was performed in 32 patients. There was a significant increase for the maximum slope and AUC egress in all three ROIs. The most significant difference was seen for the maximum slope in ROI 3 (3.7%/s to 6.6%/s, p < 0.001). In the control group, no significant differences were seen for the maximum slope and AUC egress in all ROIs.

Conclusions: This study shows the potential of ICG NIR fluorescence imaging in assessing the effect of revascularization procedures on foot perfusion.

https://journals.sagepub.com/doi/abs/10.1177/17085381211032826

Applications of intraoperative angiography in head and neck reconstruction

Laser-assisted angiography with indocyanine green (LAIG) allows objective intraoperative evaluation of tissue vascularity. This study endeavored to describe multi-centre experience with this technique in the head and neck region. A retrospective review from February 2016 till October 2018 was conducted. They included patients who underwent head and neck procedures in which LAIG was employed. The main outcome was postoperative wound complications. The study analysed the influence of LAIG results in intraoperative decision-making process.

Results: Nineteen patients were included, and follow-up was for at least 6 months. LAIG was employed in 11 local flaps, 9 free flaps and 6 cases of pharyngeal closure during total laryngectomies. Wound complications occurred in two cases with distal tip flap necrosis. LAIG findings resulted in changes in decision making intraoperatively in 84% of procedures, which consisted in trimming poorly perfused tissues. There were no pharyngocutaneous fistulas.

Conclusions: This represents a descriptive report on the use of LAIG on diverse head and neck reconstruction cases, with important impact on the decision-making process. A low number of postoperative wound complications were observed.

https://pubmed.ncbi.nlm.nih.gov/34264914/

Laparoscopic anatomical subsegmentectomy for hepatocellular carcinoma using indocyanine green fluorescence imaging

Introduction: Recently, various types of laparoscopic anatomical liver resection for hepatocellular carcinoma has been actively performed in many centers. Indocyanine green (ICG) fluorescence imaging technique has been increasingly used to visualize biliary anatomy and demarcation of the transected area. This paper reports on laparoscopic anatomical subsegmentectomy for hepatocellular carcinoma using indocyanine green fluorescence imaging technique.

Results: ICG fluorescence was well accumulated in the future liver remnant. It provided clearer demarcation than the conventional demarcation technique. The operation time was 200 minutes, and intraoperative blood loss was negligible. All surgical resection margins were confirmed to be negative for tumor cell. She was discharged on the seventh postoperative day without any complication.

Conclusions: Laparoscopic anatomical subsegmentectomy using indocyanine green fluorescence imaging was a feasible procedure. It could contribute to better identification of subsegment indicated by conventional demarcation technique.

https://pubmed.ncbi.nlm.nih.gov/34227488/

Initial experience of intraoperative fluorescent cholangiography during laparoscopic cholecystectomy: A retrospective study

Fluorescent cholangiography (FC) during laparoscopic cholecystectomy (LC) is a novel method to facilitate real-time visualization of extrahepatic biliary structures that avoiding risk of bile duct injury. Aims of this study are to investigate the feasibility and the safety of FC during LC. The study  evaluated the outcomes of FC during elective LC at our hospital from August 2017 to April 2018. Fifty-five patients who underwent FC during elective LC were enrolled in this study. Demographic and peri-operative data were recorded and analyzed. The primary endpoints were visualization rate of FC during LC. The secondary endpoint was the optimal conditions and technical details for FC included to detect any potential adverse event. The visualization rate after FC of the cystic duct, common hepatic duct and common bile duct were increased significantly compared to before FC. The identification rate of the cystic duct and common bile duct were not associated with BMI and history of acute cholecystitis. Conclusions FC enabled real-time visualization of extrahepatic biliary structures during LC. FC appears to be a safe and efficient approach for elective LC.

https://www.sciencedirect.com/science/article/pii/S2049080121005197

The efficacy and safety of laparoscopic cholecystectomy using indocyanine green fluoroscopy

Laparoscopic cholecystectomy (LCC) is now accepted as the gold standard for the management of gallbladder diseases. Currently, one of the basic techniques of general surgical residency in Korea is cholecystectomy. However, it is not easy to overcome the learning curve during fellowship period because about 150 cases are required. Intraoperative imaging using indocyanine green (ICG) might reduce learning curve and the risk of bile duct injury by improving visualization of the biliary tree. We compared the outcomes of LCC in patients with and without ICG. The authors undertook a retrospective review of total 300 conventional LCC cases with and without ICG performed by three surgeons who started the fellowship of hepatobiliary surgery in a single center.

Results: The median operation time was 43.0 vs. 39.0 min (p = 0.45) in the group with and without ICG, respectively. The rate of conversion was 4.6% in the group without ICG, while 2.5% in the group with ICG. Bile duct injury occurred 1% vs. 2.2% in the group with and without ICG, respectively (p < 0.05).

Conclusions: LCC with ICG enables a better visualization and identification of biliary tree and should be considered as a means of increasing the safety and reducing learning curve of LCC.

https://pubmed.ncbi.nlm.nih.gov/34230390/

Indocyanine Green Angiography for Quality Assessment of the Kidney During Transplantation: An Outcome Predictor Prospective Study

Microvascular damage is the main cause of delayed graft function (DGF) after kidney transplant. The aim of the study was to explore the capability of intraoperative indocyanine green (ICG) angiography to examine the microvasculature of the kidney.

The study participants conducted a prospective cohort study on 37 kidney transplant recipients in a high-volume kidney transplant center. During surgery, after graft implant, an ICG angiography was performed through a high-definition Storz camera system. 

Results: This study demonstrates that intraoperative ICG angiography may be used to assess the microvasculature of the graft.

https://www.sciencedirect.com/science/article/abs/pii/S004113452100422X