Author: fidelmac

Background: Indocyanine green (ICG) fluorescence has proven to be a high potential navigation tool during liver surgery; however, its optimal usage is still far from being standardized. A systematic review was conducted on MEDLINE/PubMed for English articles that contained the information of dose and timing of ICG administration until February 2021. Successful rates of tumor detection and liver segmentation, as well as tumor/patient background and imaging settings were also reviewed. The quality assessment of the articles was performed in accordance with the Scottish Intercollegiate Guidelines Network (SIGN).

Results: For tumor detection, majority {of studies} used the dose of 0.5 mg/kg within 14 days before the operation day, and an additional administration (0.02-0.5 mg/kg) in case of longer preoperative interval. Tumor detection rate was reported to be 87.4% (range, 43%-100%) with false positive rate reported to be 10.5% (range, 0%-31.3%). For negative staining method, the majority used 2.5 mg/body, ranging from 0.025 to 25 mg/body. For positive staining method, the majority used 0.25 mg/body, ranging from 0.025 to 12.5 mg/body. Successful segmentation rate was 88.0% (range, 53%-100%).

Conclusion: The time point and dose of ICG administration strongly needs to be tailored case by case in daily practice, due to various tumor/patient backgrounds and imaging settings.

https://pubmed.ncbi.nlm.nih.gov/35121701/

Background: Securing the proximal resection margin in totally laparoscopic distal gastrectomy for gastric cancer is related to curability and recurrence, while reducing the operation time is related to patient safety. This study aimed to investigate the role of indocyanine green (ICG) fluorescent dye marking in totally laparoscopic distal gastrectomy, whether it is an oncologically safe and accurate procedure that can be conducted in a single centre.

Methods: The data of 93 patients who underwent laparoscopic-assisted distal gastrectomy (non-ICG group) or totally laparoscopic distal gastrectomy using ICG (ICG group) between 2010 and 2020 were retrospectively reviewed. To correct for confounding factors, a propensity score matching was performed.

Results: Proximal resection margin did not vary with the ICG injection site after the propensity score matching (lower ICG, 3.84 cm vs. lower non-ICG, 4.42 cm, p = 0.581; middle ICG, 3.34 cm vs. middle non-ICG, 3.20 cm; p = 0.917), while the operation time was reduced by a mean of 34 min in the ICG group (ICG, 239.3 [95% confidence interval, 220.1-258.5 min]; non-ICG, 273.0 [95% confidence interval, 261.6-284.4] min; p = 0.006).

Conclusions: ICG injection for securing the proximal resection margin in totally laparoscopic distal gastrectomy is an oncologically safe and accurate procedure, with the advantage of reducing the operation time of gastric cancer surgery while it has the benefit of locating the tumour or clips when it is impossible to locate the tumour during surgery due to the inability to perform an endoscopic examination or when it is hard to directly palpate the tumour or clips in the operating theatre; this can be performed at a single centre.

https://pubmed.ncbi.nlm.nih.gov/35090476/

Background: Augmented reality robot-assisted partial nephrectomy (AR-RAPN) is limited by the need of a constant manual overlapping of the hyper-accuracy 3D (HA3DTM) virtual models to the real anatomy. This paper captures preliminary experience with automatic 3D virtual model overlapping during AR-RAPN.

Materials: To reach a fully automated HA3DTM model overlapping, we pursued computer vision strategies, based on the identification of landmarks to link the virtual model. Due to the limited field of view of RAPN, we used the whole kidney as a marker. Moreover, to overcome the limit of similarity of colors between the kidney and its neighboring structures, we super-enhanced the organ, using the NIRF Firefly® fluorescence imaging technology. A specifically developed software named “IGNITE” (Indocyanine GreeN automatIc augmenTed rEality) allowed the automatic anchorage of the HA3D™ model to the real organ, leveraging the enhanced view offered by NIRF technology.

Results: Ten automatic AR-RAPN were performed. For all the patients a HA3D™ model was produced and visualized as AR image inside the robotic console. During all the surgical procedures, the automatic ICG-guided AR technology successfully anchored the virtual model to the real organ without hand-assistance (mean anchorage time: 7 seconds), even when moving the camera throughout the operative field, while zooming and translating the organ. In 7 patients with totally endophytic or posterior lesions, the renal masses were correctly identified with automatic AR technology, performing a successful enucleoresection. No intraoperative or postoperative Clavien >2 complications or positive surgical margins were recorded.

Conclusions: Our pilot study provides the first demonstration of the application of computer vision technology for AR procedures, with a software automatically performing a visual concordance during the overlap of 3D models and in vivo anatomy.

https://pubmed.ncbi.nlm.nih.gov/35063460/

Objective: To compare multimodal imaging findings in patients with choroidal lymphoma (CL).

Methods: Multicenter retrospective observational case series. Multimodal imaging features of patients with CL were reviewed with particular attention to the patterns of choroidal infiltration on indocyanine green angiography (ICGA) and optical coherence tomography (OCT).

Results: Eighteen eyes of 15 patients were included in this study. Average tumor thickness on ultrasonography was 2.6 mm (range, 1.2-5.7 mm). Choroidal infiltration on ICGA was characterized by multifocal, round areas (300-500 microns diameter) of hypocyanescence in all cases, whereas OCT at the same region disclosed diffuse choroidal infiltration. By OCT, the tumor surface contour was primarily placid (22%), dome-shaped (11%), or undulating (67%).

Conclusions: In this analysis of eyes with CL, ICGA demonstrated multifocal sub-millimeter regions of choroidal hypocyanescence whereas OCT documented diffuse choroidal infiltration. This incongruence could be a distinctive diagnostic feature of choroidal lymphoma, assisting with differentiation from other pathological entities.

https://pubmed.ncbi.nlm.nih.gov/35050836/

The aim of this study was to prove the hypothesis that intraoperative fluorescence-angiography using indocyanine-green (ICGFA) can be used to predict the occurrence of perfusion-associated complications following microvascular reconstruction. Data of 67 patients (male/female: 41/26) with an average age of 64 years (range 29–84 years) were analyzed. In 10 of these patients, postoperative perfusion-associated complications were observed (arterial/venous/microcirculatory: 4/3/3; p = 0.12). The analysis of the intraoperatively obtained flow parameters showed a significant difference in the ratio of maximum and minimum intensity in arterial pedicle perfusion (Fmax/min) of patients with and without complications (with vs. without complications: 2.3 ± 1.0 vs. 5.0 ± 4.9; p < 0.01) and strong correlation of the mentioned parameter with the occurrence of perfusion-associated complications (odds ratio = 0.27; p = 0.01).

Potentially, intraoperative near-infrared ICG-based fluorescence-angiography in the pedicle vessels of a free flap may identify parameters of blood flow that can be used to predict perfusion-associated flap failure, which could influence the intraoperative decision to redo the anastomosis. The present study shows the value of ICG fluorescence-angiography as a routine clinical tool to predict flap failure after microvascular reconstruction in the head and neck region. The data indicate that ICGFA may, in the future, provide an objective method to decide intraoperatively whether or not to immediately revise an anastomosis to prevent flap loss or salvage surgery.

https://www.sciencedirect.com/science/article/abs/pii/S1010518221002249?via%3Dihub

Objectives: The blood supply of the transposed jejunum was assessed by ICG fluorescence imaging in jejunal interposition, and the correlation with anastomotic leakage or transposed jejunal necrosis was analyzed, aim to explore the value of the application ICG fluorescence imaging technology.

Methods: 84 esophageal reconstructions with jejunal interposition without supercharging were retrospectively analyzed. Intraoperatively, the blood supply of transposed jejunal was observed using ICG fluorescence endoscopy. ROC curve of T1/2 was constructed to calculate the corresponding T1/2max value of the region where the transposed jejunal want to be anastomosed with esophageal stump, the relationship between T1/2max value and anastomotic leakage or transposed jejunal necrosis was analyzed.

Results: The occurrence of anastomotic leakage and transposed jejunal necrosis was 9.5%, In the ROC curve, the maximum value of the Youden index was 0.691, the T1/2max value was 5.35 s. When T1/2max value > 5.35 s correspondingly, the probability of anastomotic leakage or transposition jejunal necrosis was 33.3% (7/21); when T1/2max value ≤ 5.35 s, the probability of anastomotic leakage or transposition jejunal necrosis was 1.6% (1/63). The difference between the two groups was statistically significant (P < 0.05).

Conclusion: ICG fluorescent imaging can effectively assess the blood supply of transposed jejunum. When T1/2max > 5.35, the possibility of the incidence rate of anastomotic leakage or transposed jejunum necrosis increases, this will remind the operators to take corresponding remedial measures during operation.

https://pubmed.ncbi.nlm.nih.gov/35024927/

Introduction: Near-infrared (NIR) fluorescence angiography (FA) is an augmented reality (AR) technique. When used in the operating room, it allows colorectal surgeons to visualize and evaluate intestinal blood flow in real time…. Evaluation of perfusion with FA in augmented reality mode has an impact on reducing the ALR (anastomotic leakage rate) in rectal resections.

Methods: Data analysis of patients after minimally invasive surgery (MIS) for middle and lower rectal adenocarcinoma with total mesorectal excision (TME) using fluorescent angiography (FA) with indocyanine green (ICG) (100 patients, 20152019) were subsequently compared with a historical control group (100 patients) operated on for the same diagnosis before the introduction of the FA-ICG method (20122015) using minimally invasive approach (MIS). The patients were operated on consequently at one workplace.

Results: In fifteen patients (15%), the resection line was shifted due to insufficient perfusion detected by FA-ICG. The incidence of AL was lower in the group with FA compared to the group without FA (9% vs. 19%, p=0.042, &#967; test). A retrospective analysis of the group revealed a significant risk factor (RF) for the anastomotic leak, namely diabetes (p=0.036) and, among others, a protective factor, application of the transanal drain (NoCoil) (p=0.032).

Conclusion: The introduction of new procedures and the use of new technologies, such as the use of the FA method in the AR mode in resections of the rectum with TME for cancer can lead to a reduction in the incidence of anastomotic leakage.

https://pubmed.ncbi.nlm.nih.gov/35021848/

One of the complications of free flap breast reconstruction is the occurrence of skin – and fat necrosis. Intra-operative use of near-infrared (NIR) fluorescence imaging with Indocyanine Green (ICG) has the potential to predict these complications. In this study, quantification of the fluorescence intensity measured in free flap breast reconstruction was performed to gain insight in the perfusion patterns observed with ICG NIR fluorescence imaging.

ICG NIR fluorescence imaging was performed in patients undergoing free flap breast reconstruction following mastectomy. After completion of the arterial and venous anastomosis, 7.5mg ICG was administered intravenously. The fluorescence intensity over time was recorded using the Quest Spectrum platform®. Four regions of interest (ROI) were selected based on location and interpretation of the NIR fluorescence signal: 1. The perforator, 2. Normal perfusion, 3. Questionable perfusion and 4. Low perfusion. Time-intensity curves were analyzed and two parameters were extracted: Tmax and Tmax slope. Successful ICG NIR fluorescence imaging was performed in 13 patients undergoing 17 free flap procedures. Region selection included 16 perforator -, 17 normal perfusion -, 8 questionable perfusion – and 5 low perfusion ROIs. Time-intensity curves of the perforator ROIs were comparable to the ROIs of normal perfusion and demonstrated a fast inflow. No outflow was observed for the ROIs with questionable and low perfusion. Conclusion This study provides insight in the perfusion patterns observed with ICG NIR fluorescence imaging in free flap breast reconstruction. Future studies should correlate quantitative parameters with clinical perfusion assessment and outcome.

https://www.jprasurg.com/article/S1748-6815(22)00003-1/fulltext