Author: fidelmac

In head and neck oncologic surgery a reconstructive phase is often required and pedicled flaps are still a viable option, though they may need a pedicle division performed at a later stage. Several techniques are commonly used for perfusion assessment of the flaps, with indocyanine green (ICG) fluorescence video-angiography representing a promising tool. We used ICG video-angiography to evaluate the perfusion of two of the most commonly adopted pedicled flaps in the head and neck field (the supraclavicular and the paramedian forehead flap) before and after second-stage pedicle division, allowing a safer in-setting.

Moreover, the new high-resolution device that we have employed added further accuracy to the traditional video-angiography, providing a real-time flap-to-normal skin ICG ratio. Indeed, ICG video-angiography proved to be a useful tool in head and neck reconstructive surgery and it may allow an earlier second-stage pedicle division.

https://pubmed.ncbi.nlm.nih.gov/35366038/

Introduction Anastomotic leakage (AL) is one of the major complications after colorectal surgery. Compromised tissue perfusion at the anastomosis site increases the risk of AL. Several cohort studies have shown that indocyanine green (ICG) combined with fluorescent near-infrared imaging is a feasible and reproducible technique for real-time intraoperative imaging of tissue perfusion, leading to reduced leakage rates after colorectal resection. Unfortunately, these studies were not randomised. Therefore, we propose a randomised controlled trial to assess the value of ICG-guided surgery in reducing AL after colorectal surgery.

Methods and analysis A multicentre, randomised controlled clinical trial will be conducted to assess the benefit of ICG-guided surgery in preventing AL. A total of 978 patients scheduled for colorectal surgery will be included. Patients will be randomised between the Fluorescence Guided Bowel Anastomosis group and the Conventional Bowel Anastomosis group. The primary endpoint is clinically relevant AL (defined as requiring active therapeutic intervention or reoperation) within 90 days after surgery. Among the secondary endpoints are 30-day clinically relevant AL, all-cause postoperative complications, all-cause and AL-related mortality, surgical and non-surgical reinterventions, total surgical time, length of hospital stay and all-cause and AL-related readmittance.

Ethics and dissemination This protocol has been approved by the Medical Ethical Committee Leiden-Den Haag-Delft (METC-LDD) and is registered at ClinicalTrials.gov and trialregister.nl. The results of this study will be reported through peer-reviewed publications and conference presentations.

https://bmjopen.bmj.com/content/12/4/e051144

Mastectomy skin flaps (MSF) necrosis is one of the most relevant complications following mastectomies with immediate breast reconstruction. The study evaluates a possible correlation between MSF qualitative and quantitative perfusion grade, using ICG angiography, and skin necrosis. Methods. Consecutive women scheduled for nipple/skin-sparing/skin-reducing mastectomy between May 2020 and April 2021 were prospectively enrolled. Patients were divided into Group 1 in the absence of superficial and full-thickness necrosis (SN; FTN) and Group 2 in the presence of both. T1 (time between ICG injection and the initial perfusion of the least perfused MSF area), ICG-Q1, and ICG-Q% (absolute and relative perfusion values of the least vascularized area) were collected. Results. 38 breasts were considered. FTN was reported in 4 breasts (10.5%) and SN in 3 (7.9%). The two groups statistically differ in T1 (Group2 > Group1) and ICG-Q% (Group1 > Group2) ( < 0.05). T1 could statistically predict ICG-Q1 and ICG-Q%. Both quantitative values have a sensitivity of 57% and a NPV of 89%; ICG-Q% shows higher specificity (81% vs 77%) and PPV (40% vs 36%). Conclusions. Quantitative ICG angiography may additionally reduce MSF necrosis. Moreover, longer T1 may indicate possible postoperative necrosis. Considering these factors, intraoperative changes of reconstructive strategy could be adopted to reduce reconstructive failure.

https://www.hindawi.com/journals/tbj/2022/5142100/

The wide availability of near infrared light sources in interventional medical imaging stacks enables non-invasive quantification of perfusion by using fluorescent dyes, typically Indocyanine Green (ICG). Due to their often leaky and chaotic vasculatures, intravenously administered ICG perfuses through cancerous tissues differently. We investigate here how a few characteristic values derived from the time series of fluorescence can be used in simple machine learning algorithms to distinguish benign lesions from cancers. These features capture the initial uptake of ICG in the colon, its peak fluorescence, and its early wash-out. By using simple, explainable algorithms we demonstrate, in clinical cases, that sensitivity (specificity) rates of over 95% (95%) for cancer classification can be achieved.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8861725/

Fluorescent cholangiography using intravenous indocyanine green (ICG) is a noninvasive technique that enables real-time intraoperative imaging of biliary anatomy. The objective of this study was to visualise the biliary anatomy in routine and complicated cases of laparoscopic cholecystectomy (LC).

Methods: This was a prospective observational study of patients undergoing LC for various indications. After obtaining consent, 5 mg/1 ml of ICG dye was administered intravenously in each patient, 2 h before the incision time. LC was performed by standard critical view of the safety technique. The biliary tree was visualised using near-infrared (NIR) view before clipping any structure. Intra-operative findings, visibility of ducts in the NIR view, conversion, adverse reactions to ICG and post-operative outcomes in all patients were recorded.

Results: Out of 43 patients undergoing LC, 24 had cholelithiasis, 10 had acute cholecystitis, 3 had chronic cholecystitis, 1 had mucocele of the gall bladder, 1 had gall bladder polyp and 4 cases had common bile duct (CBD) stone clearance with endoscopic retrograde cholangiopancreatography. Cystic duct (CD) and CBD were visualised in 100% of cases among all groups except for those with acute cholecystitis where CD and CBD were visualised in 90% and 80% of cases, respectively, and in chronic cholecystitis CD and CBD were visualised in 66.6% and 80% of patients, respectively. There was one elective conversion in the chronic cholecystitis group due to dense adhesions and non-progression. Only the CBD was visualised in this case. There were no cases of CBD injury or any allergic reactions to the dye.

Conclusions: Fluorescent cholangiography during LC is a safe and non-invasive method, allowing superior anatomical visualisation of the biliary tree in comparison to simple laparoscopy. This method can correct misinterpretation errors and detect aberrant duct anatomy, thus increasing the confidence of the operating surgeon enabling safe dissection. This simple technique has the potential to become standard practice to avoid bile duct injury during LC.

https://pubmed.ncbi.nlm.nih.gov/35313432/

Vascular patency is the key element for high flap survival rates. The purpose of this study was to assess and compare the blood flow characteristics of deep inferior epigastric perforator (DIEP) and muscle-sparing transverse rectus abdominis musculocutaneous (ms-TRAM) flaps for autologous breast reconstruction. Methods: This prospective clinical study combined Transit-Time Flowmetry and microvascular Indocyanine Green Angiography for the measurement of blood flow volume, vascular resistance, and intrinsic transit time.

Results: Twenty female patients (mean age, 52 years) received 24 free flaps (14 DIEP and 10 ms-TRAM flaps). The mean arterial blood flow of the flap in situ was 7.2 ± 1.9 mL/min in DIEP flaps and 11.5 ± 4.8 mL/min in ms-TRAM flaps (p &lt; 0.05). After anastomosis, the mean arterial blood flow was 9.7 ± 5.6 mL/min in DIEP flaps and 13.5 ± 4.2 mL/min in ms-TRAM flaps (p = 0.07). The arterial vascular resistance of DIEP flaps was significantly higher than that of ms-TRAM flaps. The intrinsic transit time of DIEP flaps was 52 ± 18 s, and that of ms-TRAM flaps was 33 ± 11 s (p &lt; 0.05). The flap survival rate was 100%. One DIEP flap with the highest intrinsic transit time (77 s) required surgical revision due to arterial thrombosis.

Conclusion: In this study, we established the blood flow characteristics of free DIEP and ms-TRAM flaps showing different blood flow rates, vascular resistances, and intrinsic transit times. These standard values will help to determine the predictive values for vascular compromise, hence improving the safety of autologous breast reconstruction procedures.

https://pubmed.ncbi.nlm.nih.gov/35330481/

Objective: To assess the role of indocyanine green in liver transplantation and to lay the foundation for its application in clinical practice.

Background: Liver transplantation offers the best prognosis for patients with end-stage liver disease. However, this invasive procedure involves multiple well-known challenges, including complications due to graft rejection and dysfunction, surgical risks, and critical postoperative management. Intraoperative methods to assess graft function rely on conventional methods, such as blood chemistries and Doppler ultrasound. However, these methods are limited in their abilities to assess liver conditions, predict functional outcomes of the graft, and prevent surgical complications. Thus, identifying a more effective and comprehensive detection method is necessary.

Methods: The information used to write this narrative review was collected from the references’ opinions and conclusions.

Conclusions: Indocyanine green can effectively monitor blood flow during surgery, evaluate donor graft function, and monitor the recipients functional status during and after surgery. It may also help surgeons to predict the prognosis of patients throughout the liver transplantation process, from assessing patients for liver transplantation status to postoperative management. Therefore indocyanine green should be routinely used in liver transplantation to help re-organize the transplant waiting list and improve the surgical outcomes of liver transplantation patients.

https://pubmed.ncbi.nlm.nih.gov/35282122/

Indocyanine green, near infrared, fluorescence angiography (ICG-FA) is increasingly adopted in colorectal surgery for intraoperative tissue perfusion assessment to reduce anastomotic leakage rates. However, the economic impact of this intervention has not been investigated.

This study is a cost analysis of the routine use of ICG-FA in colorectal surgery from the hospital payer perspective. A decision analysis model was developed for colorectal resections considering two scenarios: resection without using ICG-FA and resection with intraoperative ICG-FA for anastomotic perfusion assessment. Incorporated into the model were the costs of ICG agent, fluorescence angiography equipment, surgery, anastomotic leak, and the leak rates with and without ICG-FA.  

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

Using the best available evidence and most conservative base case values, routine use of ICG-FA in colorectal surgery was found to be cost saving. Since the evidence suggests there is a reduction in leak rate, the routine use of ICG-FA is a dominating strategy.

https://pubmed.ncbi.nlm.nih.gov/35290507/

Fluorescence imaging in colorectal surgery is considered a novel predominantly intraoperative method of ensuring a greater surgical success. The use of fluorescence is linked to advanced tumor visualization and projection of its lymphatics, both vessels and nodes, which results in a higher chance of achieving a total excision. Additionally, iatrogenic complications prove to be reduced using fluorescence during the surgical excision. The combination of fluorescence and artificial intelligence to better facilitate oncological surgery will soon become an established approach in operating rooms worldwide.

https://pubmed.ncbi.nlm.nih.gov/35232304/

With the development of three-dimensional (3D) simulation software, preoperative simulation technology is almost completely established. The remaining issue is how to recognize anatomy three-dimensionally. Extended reality is a newly developed technology with several merits for surgical application: no requirement for a sterilized display monitor, better spatial awareness, and the ability to share 3D images among all surgeons. Various technology or devices for intraoperative navigation have also been developed to support the safety and certainty of liver surgery.

Consensus recommendations regarding indocyanine green fluorescence were determined in 2021. Extended reality has also been applied to intraoperative navigation, and artificial intelligence (AI) is one of the topics of real-time navigation. AI might overcome the problem of liver deformity with automatic registration. Including the issues described above, this article focuses on recent advances in simulation and navigation in liver surgery from 2020 to 2021.

https://pubmed.ncbi.nlm.nih.gov/35261944/