Intraoperative Fluorescence Imaging Research Articles

Fluorescence detection of pituitary neuroendocrine tumour during endoscopic transsphenoidal surgery using bevacizumab-800CW: a non-randomised, non-blinded, single centre feasibility and dose finding trial [DEPARTURE trial

Achieving endocrine remission by gross total resection is challenging in pituitary neuroendocrine tumours (PitNETs) with cavernous sinus invasion. This study aims to assess the safety, feasibility, and optimal dose for intraoperative fluorescence imaging as an added instrument to discriminate PitNET from surrounding tissue using bevacizumab-800CW, targeting vascular endothelial growth factor A (VEGF-A). In part I, dose-escalation (0-4∙5-10-25mg) was performed in 4 groups of 3 patients with PitNETs Knosp grade 3-4. In part II, after interim analysis, the 10mg and 25mg groups were expanded to a total of 6 patients. Quantitative fluoroscence molecular endoscopy consisted of wide field fluorescence molecular endoscopy and multi-diameter single fiber reflectance / single fiber fluorescence spectroscopy. Mean fluorescence intensity (MFI) of the fresh surgical specimen was calculated and VEGF-staining was performed. Eighteen patients were included. All doses were well tolerated. Three serious adverse events were registered, but none were tracer-related. Part I showed an adequate in-vivo tumour-to-background ratio for both 10mg (TBR 2∙00 [1∙86, 2∙19]) and 25mg (TBR 2∙10, [1∙86, 2∙58]). Part II revealed a substantially higher MFI in the 25mg group. With both 10mg and 25mg a statistically significant difference between tumour and surrounding tissue was detected (p < 0∙0001). All surgical specimens had VEGF-A expression. This study demonstrates the safety and feasibility of quantitative fluorescence molecular endoscopy during PitNET surgery. Both 10mg and 25mg bevacizumab-800CW result in clear differentiation in-vivo, with improved contrast ex-vivo (MFI) in the 25mg group. NCT04212793 / Study Details| Detection of PitNET Tissue During TSS Using Bevacizumab800CW| ClinicalTrials.gov.

Immunohistochemical Evaluation of Potential Biomarkers for Targeted Intraoperative Fluorescence Imaging in Endometriosis: Towards Optimizing Surgical Treatment.

Surgical intervention for endometriosis is an important treatment modality, yet incomplete resection resulting from poor visibility of affected tissue and consequently recurrence of disease remains a prevalent challenge. Intra-operative visualization of endometriosis, enabling fluorescence-guided surgery (FGS), could help to optimize surgical treatment. A biomarker, upregulated in endometriosis compared to adjacent tissue, is required to use as a target for FGS. Immunohistochemistry was used to evaluate protein expression of a selection of previously identified potential biomarkers. Ten biomarkers were stained in a large cohort of 84 tissues, both deep and peritoneal endometriosis and tissue without endometriosis, all from patients with confirmed endometriosis. MMP11 and VCAN showed the largest upregulation in endometriosis compared to adjacent tissue and showed a membranous or extracellular staining pattern. MMP11 is a promising target for glandular and stromal visualization, VCAN for stromal visualization only. For both biomarkers, upregulation was high in both peritoneal and deep endometriosis and for patients with and without hormonal medication. Other stained biomarkers showed non-beneficial characteristics based on staining pattern or upregulation. Analysis of all endometriosis samples showed that combined glandular and stromal targeting is expected to result in optimal visualization of endometriosis. Further research is needed to determine whether targeting one biomarker is sufficient for this goal, or if dual targeting is necessary. Development of clinical tracers for VCAN and MMP11 is necessary.

Indocyanine green fluorescence imaging: Assessment of perfusion at pancreatic resection margin during pancreatoduodenectomy: A cross sectional study.

Clinically relevant-postoperative pancreatic fistula (CR-POPF) is one of the dreaded complications of pancreatoduodenectomy. Vascularity of the stump of the pancreas during pancreatico-enteric anastomosis is considered one of the major determinants of POPF. Indocyanine green (ICG) is one of the modality for vascular assessment; hence, we aimed to evaluate the role of ICG fluorescence imaging to assess the vascularity of the pancreatic stump during pancreatoduodenectomy. The study was conducted at Kathmandu Medical College, Kathmandu, Nepal, during the period of 1 year (June 01, 2022-July 31, 2023). All of the patients who were undergoing pancreatoduodenectomy were included in the study. In all cases, intraoperatively, ICG fluorescence detection at the pancreatic stump margin was evaluated using near-infrared light. A total of 28 patients underwent PD during this period. The ICG fluorescence imaging was positive at the pancreatic stump margin in 25 out of the 28 patients (89%), and in three cases, the florescence was negative. In patients who had negative fluorescence, revision of the stump margin was performed. Clinically relevant POPF was noted in 2 out of 28 cases, which had a soft pancreas with a small duct, although the pancreatic stump margin had good ICG florescence per-operatively. ICG is inexpensive and a safe dye to use in clinical practice. We can objectively assess the pancreatic stump vascularity using intraoperative ICG fluorescence imaging, thereby potentially decreasing postoperative pancreatic fistula.

Use of indocyanine green-human serum albumin complexes in fluorescence image-guided laparoscopic anatomical liver resection: a case series study (with video)

BackgroundThis study aimed to investigate the feasibility and efficacy of near-infrared fluorescence-guided laparoscopic anatomical hepatectomy (LAH) using a novel indocyanine green (ICG)-human serum albumin complex (HSA) in patients with hepatocellular carcinoma.MethodsClinical data of hepatocellular carcinoma patients who underwent ICG-HSA fluorescence-guided LAH at our center from January 2024 to April 2024 were prospectively collected and analyzed. Ultraviolet absorption spectroscopy was used to test the absorption and stability of ICG-HSA complex solutions under different conditions. After determining the optimal ratio, the complex was administered intravenously during surgery to perform negative staining via Glissonean pedicle isolation. LAH was performed along the fluorescence-demarcated boundaries.ResultsThirty-one patients were included (24 men; mean age, 54.61 ± 13.54 years). The median maximum tumor diameter was 2.80 (interquartile range [IQR], 2.00–4.00) cm. S8 segmentectomy (22.6%) and right posterior segmentectomy (19.4%) were the most common resections performed. Successful fluorescence negative staining was achieved in all patients using ICG and HSA at a 1:6 molar ratio at room temperature. Mean operation time was 297.58 ± 85.53 min, Median intraoperative blood loss was 100.0 mL (IQR, 50.0–200.0). The median surgical margin distance was 0.90 cm (IQR, 0.40–1.50). The postoperative complication rate was 45.2% (35.5% Clavien–Dindo grade I and 9.7% grade II). The median length of hospital stay was 5.0 days (IQR, 4.0–5.0).ConclusionICG-HSA-assisted LAH is safe and feasible. Compared with free ICG, the novel ICG-HSA complex exhibits better optical properties and in vivo stability, which can improve the accuracy of intraoperative liver segment localization and optimize the anatomical dissection plane. It has the potential to become an ideal fluorescent imaging agent for anatomical hepatectomy.Graphical abstractA In vitro binding experiments of indocyanine green (ICG) and human serum albumin (HSA) suggested that a 1:6 molar ratio and a configuration temperature of 37°C were optimal. B During surgery, after extrahepatic Glissonean isolation of the liver pedicle planned for resection, the ICG-HSA complex was administered through a peripheral vein using an infusion pump. C ICG-HSA metabolism comprises three stages: intravascular, liver, and systemic clearance. D The actual intraoperative fluorescence imaging and guidance effects of ICG-HSA in laparoscopic fluorescence negative-staining right hemihepatectomy.

Indocyanine Green (ICG): A Versatile Tool in Enhancing Precision in Minimally Invasive Thoracic Surgery

Intraoperative fluorescence imaging using indocyanine green (ICG) is an innovative and safe tool in minimally invasive thoracic surgery. It provides real-time imaging capabilities that can enhance surgical precision. We describe several clinical uses of ICG including intersegmental plane identification, thoracic duct injury localisation, anomalous systemic artery identification in pulmonary sequestration, phrenic nerve identification, and sentinel lymph node mapping. Successful visualisation of ICG was achieved to identify intra-thoracic anatomical structures and boundaries, allowing for safe and precise dissection.

Application of Indocyanine Green Fluorescence Imaging During Laparoscopic Reoperations of the Biliary Tract Enhances Surgical Precision and Efficiency.

A history of abdominal surgery is considered a contraindication for laparoscopic procedures. However, the advancements in laparoscopic instruments and techniques have facilitated the performance of increasingly intricate operations, even in patients with prior abdominal surgeries. ICG fluorescence imaging technology offers advantages in terms of convenient operation and clearer intraoperative bile duct imaging, as confirmed by numerous international clinical studies on its feasibility and safety. The application of ICG fluorescence imaging technology in repeat laparoscopic biliary surgery, however, lacks sufficient reports. The clinical data of patients who underwent elective reoperation of the biliary tract in our department between January 2020 and June 2022 were retrospectively analyzed. ICG was injected peripherally before the operation, and near-infrared light was used for 3-dimensional imaging of the bile duct during the operation. Altogether, 143 patients were included in this study and divided into the fluorescence and nonfluorescence groups according to the inclusion criteria. Among the 26 patients in the fluorescence group, cholangiography was successfully performed in 24 cases, and the success rate of intraoperative biliary ICG fluorescence imaging was 92.31%. The intraoperative biliary tract identification time was significantly different between the fluorescence and nonfluorescence groups, but no statistical difference was observed in the final operation method, operative time, and intraoperative blood loss between the 2 groups. Although there was no significant difference in the postoperative ventilation rate, incidence of bile leakage, and stone recurrence rate at 6 months postoperatively between the 2 groups (P>0.05), a significant difference in postoperative hospitalization days was observed (P=0.032). The application of ICG fluorescence imaging technology in laparoscopic reoperation of the biliary tract is useful for the early identification of the biliary tract during operation, thereby shortening the operative time and reducing the risk of damage to nonoperative areas. This approach also enhances the visualization of the biliary system and avoids secondary injury intraoperatively due to poor identification of the biliary system. This technique is safe for repeat biliary tract surgery and has a good application prospect.

Use of intra-operative fluorescence imaging in periprosthetic joint infection: State of the art and future perspectives.

In periprosthetic joint infections (PJIs), the surgeon's role becomes pivotal in addressing the infection locally, necessitating the surgical removal of infected and necrotic tissue. Opportunity to enhance the visualization of infected tissue during surgery could represent a game-changing innovation. The aim of this narrative review is to delineate the application of intraoperative fluorescence imaging for targeting infected tissues in PJIs. A systematic review, adhering to the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines, was carried out. The search included multiple online database; MEDLINE, Scopus, and Web of Science. For data extraction the following were evaluated: (i) diagnosis of musculoskeletal infection; (ii) use of intraoperative fluorescence imaging; (iii) infected or necrotic tissues as target. Initially, 116 studies were identified through online database searches and reference investigations. The search was narrowed down to a final list of 5 papers for in-depth analysis at the full-text level. Subsequently, 2 studies were included in the review. The study included a total of 13 patients, focusing on cases of fracture-related infections of the lower limbs. The primary and crucial role for orthopedic surgeons in PJIs is the surgical debridement and precise removal of necrotic and infected tissue. Technologies that enable clear and accurate visualization of the tissue to be removed can enhance the eradication of infections, thereby promoting healing. A promising avenue for the future involves the potential application of intraoperative fluorescence imaging in pursuit of this objective.

400. MODIFICATION OF THE LESSER CURVATURE INCISION ENHANCES GASTRIC CONDUIT BLOOD FLOW AND DECREASE ANASTOMOTIC LEAKAGE RISK AFTER ESOPHAGECTOMY

Abstract Background We conducted this study to investigate the effectiveness of a modified incision line on the lesser curvature for gastric conduit formation during esophagectomy in enhancing the perfusion of the gastric conduit, as determined by indocyanine green (ICG) fluorescence imaging, and reducing the incidence of anastomotic leakage. Methods A total of 272 patients who underwent esophagectomy at our institution between June 2014 and August 2022 were enrolled in the study. The patients were divided into two groups in accordance with the type of cutline on the lesser curvature: the Conventional group, consisting of patients operated on until 2018 (Conventional group; n = 141), in which the traditional cutline (5.0 cm from the pylorus in routine) was adopted, and the Current group, consisting of patients operated on from 2019 until date (Current group; n = 131), in which a modified cutline on the lesser curvature was adopted, that allowed preservation of the entire right gastric artery was adopted (hereinafter, modified cutline) was adopted. Gastric conduit perfusion during the surgery was assessed by intraoperative ICG fluorescence imaging, and the clinical outcomes after esophagectomy were also evaluated. Results All patients underwent esophagectomy with regional lymph node dissection and gastric conduit reconstruction via the retrosternal route. The distance from the pylorus to the cutline was significantly longer in the Current group as compared with the Conv group (median: 9.0 cm vs. 5.0 cm, p &amp;lt; 0.001). The blood flow speed in the gastric conduit wall assessed by ICG fluorescence imaging was significantly higher in the Current group than that in the Conventional group (median: 2.81 cm/sec vs. 2.54 cm/sec, p = 0.001). Furthermore, the incidence of anastomotic leakage was significantly lower (p = 0.024) and the hospital stay significantly shorter (p &amp;lt; 0.001) in the Current group as compared with the Conventional group. Logistic regression analysis using the data of the entire cohort identified the blood flow velocity in the gastric conduit wall as the only variable that was significantly (negatively) associated with anastomotic leakage. Conclusions ICG fluorescence imaging is a feasible, reliable method for intraoperative assessment of gastric conduit perfusion. Use of the modified lesser curvature cutline could enhance gastric conduit perfusion, promote blood circulation around the anastomosis and ultimately reduce the risk of anastomotic leakage after esophagectomy.

Temporoparietal Fascial Flap Combined With Vascularized Outer Table Calvarial Bone Graft and Entire Temporalis Muscle: A Stable Pedicled Flap for Orbital Floor Reconstruction After Total Maxillectomy.

Orbital reconstruction after total maxillectomy is essential to maintain ocular function and facial contour. Free flap transfer with simultaneous orbital bone reconstruction is a straightforward approach; however, it is challenging in medically unstable patients with multimorbidity. The authors developed an easily harvested temporoparietal fascial flap combined with vascularized outer table calvarial bone and entire temporalis muscle. The authors applied this technique in an 81-year-old patient with multiple comorbidities who required orbital floor reconstruction following total maxillectomy. Intraoperative indocyanine green fluorescence imaging confirmed excellent perfusion of the temporoparietal fascia, entire temporalis muscle, and calvarial bone. Although the patient developed postoperative local wound infection, the vascularized bone graft resisted infection and preserved the orbital structure without bone exposure. Our technique is minimally invasive and results in a well-vascularized flap for orbital reconstruction after total maxillectomy involving the orbital bone, and particularly beneficial in patients with multimorbidity or at high risk of local infection.

Interim Phase II Results Using Panitumumab-IRDye800CW during Transoral Robotic Surgery in Patients with Oropharyngeal Cancer.

The incidence of oropharyngeal squamous cell carcinoma (OPSCC) has continually increased during the past several decades. Using transoral robotic surgery (TORS) significantly improves functional outcomes relative to open surgery for OPSCC. However, TORS limits tactile feedback, which is often the most important element of cancer surgery. Fluorescence-guided surgery (FGS) strategies to aid surgeon assessment of malignancy for resection are in various phases of clinical research but exhibit the greatest potential impact for improving patient care when the surgeon receives limited tactile feedback, such as during TORS. Here, we assessed the feasibility of intraoperative fluorescence imaging using panitumumab-IRDye800CW (PAN800) during TORS in patients with OPSCC. Twelve consecutive patients with OPSCC were enrolled as part of a nonrandomized, prospective, phase II FGS clinical trial using PAN800. TORS was performed with an integrated robot camera for surgeon assessment of fluorescence. Intraoperative and ex vivo fluorescence signals in tumors and normal tissue were quantified and correlated with histopathology. Intraoperative robot fluorescence views delineated OPSCC from normal tissue throughout the TORS procedure (10.7 mean tumor-to-background ratio), including in tumors with low expression of the molecular target. Tumor-specific fluorescence was consistent with surgeon-defined tumor borders requiring resection. Intraoperative robot fluorescence imaging revealed an OPSCC fragment initially overlooked during TORS based on brightfield views, further substantiating the clinical benefit of this FGS approach. The results from this patient with OPSCC cohort support further clinical assessment of FGS during TORS to aid resection of solid tumors.

Fluorescence imaging‐guided pelvic lymph node localization and resection of bladder cancer after intracutaneous injection of indocyanine green into the lower limbs and perineum

AbstractBackgroundPelvic lymph node dissection (PLND) in radical cystectomy (RC) is of great significance, but the method and scope of PLND remain controversial. Based on the principle of indirect lymphadenography, we designed a method to localize the whole pelvic lymph nodes by intradermal injection of indocyanine green (ICG) through the lower limbs and perineum, and to evaluate the effectiveness of this method.MethodsIn a single center, 54 bladder cancer patients who underwent RC and PLND participated in a prospective clinical trial, which began on February 28, 2022 and ended on December 30, 2022. ICG solution was injected subcutaneously at the medial malleolus of both lower extremities and at both sides of the midline of the perineum. The fluorescent laparoscopy was used to trace, locate, and remove the targeted areas under the image fusion mode. The consistency of lymph node resection was determined by histopathological diagnosis. The impact of ICG guidance on the surgical time of PLND was compared with that of 11 bladder cancer patients who underwent RC and PLND without ICG injection, serving as the control group.ResultsPerineal lower limb combined injection can provide comprehensive visualization of pelvic lymph nodes. This technique reduces PLND surgical time and increases the accuracy of PLND.ConclusionIntracutaneous injection of ICG into the lower limbs and perineum can specifically mark pelvic lymph nodes. Intraoperative fluorescence imaging can accurately identify, locate, and resect lymph nodes in the pelvic region, reducing PLND surgical time and increasing the accuracy of PLND.

The role of ureteric indocyanine green fluorescence in colorectal surgery: a retrospective cohort study

BackgroundUreteric injury (UI) is an infrequent but serious complication of colorectal surgery. Prophylactic ureteric stenting is employed to avoid UI, yet its efficacy remains debated. Intraoperative indocyanine green fluorescence imaging (ICG-FI) has been used to facilitate ureter detection. This study aimed to investigate the role of ICG-FI in identification of ureters during colorectal surgery and its impact on the incidence of UI.MethodsA retrospective cohort study involving 556 consecutive patients who underwent colorectal surgery between 2018 and 2023 assessed the utility of routine prophylactic ureteric stenting with adjunctive ICG-FI. Patients with ICG-FI were compared to those without ICG-FI. Demographic data, operative details, and postoperative morbidity were analyzed. Statistical analysis included univariable regression.ResultsUreteric ICG-FI was used in 312 (56.1%) patients, whereas 43.9% were controls. Both groups were comparable in terms of demographics except for a higher prevalence of prior abdominal surgeries in the ICG-FI group. Although intraoperative visualization was significantly higher in the ICG-FI group (95.3% vs 89.1%; p = 0.011), the incidence of UI was similar between groups (0.3% vs 0.8%; p = 0.585). Postoperative complications were similar between the two groups. Median stent insertion time was longer in the ICG-FI group (32 vs 25 min; p = 0.001).ConclusionUreteric ICG-FI improved intraoperative visualization of the ureters but was not associated with a reduced UI rate. Median stent insertion time increased with use of ureteric ICG-FI, but total operative time did not. Despite its limitations, this study is the largest of its kind suggesting that ureteric ICG-FI may be a valuable adjunct to facilitate ureteric visualization during colorectal surgery.

Surgical treatment of right colon cancer

The study aimed to perform a systematic review of the literature on surgical treatment for right colon cancer (RCC) with complete mesocolic excision (CME) and D2/D3 lymph node dissection (LND). Material and Methods. A literature review was performed for studies published between 2013 and 2023 by the online resources from the official Web sites of the societies/panels and PubMed database. Sources included guidelines, meta-analyses, randomized and nonrandomized clinical studies, guidelines by European Society of Medical Oncology, the Japanese Society for Cancer of the Colon and Rectum, and the National Comprehensive Cancer Network, Russian clinical guidelines. Results. CME significantly improved both immediate and long-term treatment results, which was confirmed by numerous meta-analyses. The extent of LND remains one of the most controversial issues in RCC. For many Asian surgeons, D3 LND is the standard procedure for the treatment of RCC, whereas the European approach is more conservative and apical lymph node dissection is not mandatory. There are also large differences in understanding the extent of D3 LND in RCC. Most surgeons understand this term as dissection of adipose tissue along the anterior and lateral surface of the superior mesenteric vein, however, there are authors who perform circular dissection along the superior mesenteric vessels, considering this extent of surgery to be the most radical. Conclusion. It is necessary to standardize methods and effective criteria for quality control of CME for RCC and LND. In this case, external independent assessment of the quality of surgical intervention is important. There is also currently a growing number of studies in which intraoperative fluorescence imaging makes it possible to better visualize the location of the apical lymph nodes and individualize LND.

Dose optimization of second window indocyanine green in meningioma patients

ObjectiveSurgery remains the first line treatment for meningiomas and can benefit from fluorescence-guided surgical techniques such as second-window indocyanine green (SWIG). In the current study, we compared the use of the standard SWIG dose of 5.0 mg/kg relative to 2.5 mg/kg indocyanine green (ICG) in meningioma patients. MethodsPatients were prospectively enrolled in an IRB-approved study of SWIG and received either the standard dose of 5.0 mg/kg or a reduced dose of 2.5 mg/kg of ICG around 24 h prior to their surgery. Intraoperative near-infrared fluorescence imaging was performed with exo- and endoscopic systems. Signal-to-background ratio (SBR) was calculated to quantify fluorescence and was compared between 5.0 mg/kg and 2.5 mg/kg ICG. All patients received pre-operative MRI and, in select cases, the pre-operative MRI was correlated to intraoperative fluorescence imaging. Results/DiscussionIn the current study, we found no significant difference in the SBR of meningiomas in patients that were administered with either 5.0 mg/kg or 2.5 mg/kg ICG. However, in five patients that received the standard-dose SWIG regimen of 5.0 mg/kg ICG we observed dose-related fluorescence quenching − referred to as “inversion” − that interfered with tumor visualization during fluorescence-guided surgery (FGS). When correlated to pre-operative MRI, a similar rim pattern was observed around the primary tumor on T2 FLAIR, which, in retrospect, could be used as a predictor for inversion during FGS in meningioma patients receiving standard-dose ICG. ConclusionThis study demonstrated that a reduced ICG dose was as effective as standard-dose SWIG in meningioma patients. We therefore recommend to adjust the standard ICG dose for meningioma patients to 2.5 mg/kg particularly when rim enhancement is observed on pre-operative T2 FLAIR.

First-in-man study of the PSMA Minibody IR800-IAB2M for molecularly targeted intraoperative fluorescence guidance during radical prostatectomy

PurposeProstate-specific membrane antigen (PSMA) is increasingly used to image prostate cancer in clinical practice. We sought to develop and test a humanised PSMA minibody IAB2M conjugated to the fluorophore IRDye 800CW-NHS ester in men undergoing robot-assisted laparoscopic radical prostatectomy (RARP) to image prostate cancer cells during surgery.MethodsThe minibody was evaluated pre-clinically using PSMA positive/negative xenograft models, following which 23 men undergoing RARP between 2018 and 2020 received between 2.5 mg and 20 mg of IR800-IAB2M intravenously, at intervals between 24 h and 17 days prior to surgery. At every step of the procedure, the prostate, pelvic lymph node chains and extra-prostatic surrounding tissue were imaged with a dual Near-infrared (NIR) and white light optical platform for fluorescence in vivo and ex vivo. Histopathological evaluation of intraoperative and postoperative microscopic fluorescence imaging was undertaken for verification.ResultsTwenty-three patients were evaluated to optimise both the dose of the reagent and the interval between injection and surgery and secure the best possible specificity of fluorescence images. Six cases are presented in detail as exemplars. Overall sensitivity and specificity in detecting non-lymph-node extra-prostatic cancer tissue were 100% and 65%, and 64% and 64% respectively for lymph node positivity. There were no side-effects associated with administration of the reagent.ConclusionIntraoperative imaging of prostate cancer tissue is feasible and safe using IR800-IAB2M. Further evaluation is underway to assess the benefit of using the technique in improving completion of surgical excision during RARP.RegistrationISCRCTN10046036: https://www.isrctn.com/ISRCTN10046036.

Patient-specific arterial input function for accurate perfusion assessment in intraoperative fluorescence imaging.

The arterial input function (AIF) plays a crucial role in correcting the time-dependent concentration of the contrast agent within the arterial system, accounting for variations in agent injection parameters (speed, timing, etc.) across patients. Understanding the significance of the AIF can enhance the accuracy of tissue vascular perfusion assessment through indocyanine green-based dynamic contrast-enhanced fluorescence imaging (DCE-FI). We evaluate the impact of the AIF on perfusion assessment through DCE-FI. A total of 144 AIFs were acquired from 110 patients using a pulse dye densitometer. Simulation and patient intraoperative imaging were conducted to validate the significance of AIF for perfusion assessment based on kinetic parameters extracted from fluorescence images before and after AIF correction. The kinetic model accuracy was evaluated by assessing the variability of kinetic parameters using individual AIF versus population-based AIF. Individual AIF can reduce the variability in kinetic parameters, and population-based AIF can potentially replace individual AIF for estimating wash-out rate ( ), maximum intensity ( ), ingress slope with lower differences compared with those in estimating blood flow, volume transfer constant ( ), and time to peak. Individual AIF can provide the most accurate perfusion assessment compared with assessment without AIF or based on population-based AIF correction.

Indocyanine green fluorescence visualizes landmark arteries for endoscopic sinus and skull base surgery

ObjectiveLandmark arteries during endoscopic sinus surgery are currently identified on the basis of anatomy, CT imaging and navigation, and Doppler flowmetry. However, the advantage of intraoperative fluorescence imaging during endoscopic sinus surgery has not been demonstrated. This study aimed to investigate whether Indocyanine Green (ICG) is useful for visualizing landmark arteries during endoscopic sinus and skull base surgery. MethodsEight patients who underwent endoscopic sinus and pituitary surgeries and consented to study participation were included. After planned procedures were performed as usual, landmark arteries were examined by ICG endoscope. Recorded video and preoperative CT images were analyzed for identification of five landmark arteries: anterior ethmoidal artery (AEA), posterior ethmoidal artery (PEA), internal carotid artery (ICA), sphenopalatine artery (SPA), and postnasal artery (PNA). Identification of arteries was evaluated three grades: identifiable, locatable, unrecognizable. ResultsEight patients and eleven sides were evaluated. The ICG dose was 2.5 mg/body and a single shot was sufficient for evaluation. 100 % of AEA was identified (9/9 sides), 86 % of PNA (6/7 sides), 56 % of ICA (5/9 sides), and 25 % of PEA and SPA (2/8 sides). ConclusionICG could visualize landmark arteries, even thin arteries like AEA, during endoscopic sinus and skull base surgeries. Visualization was affected by thickness of bone or soft tissue above arteries, blood clots, sensitivity setting, and angle and distance of near-infrared light irradiation. ICG visualization of landmark arteries may help avoid vascular injuries during endoscopic sinus and skull base surgeries, particularly of AEA, PNA and ICA.

Tumor Segmentation in Intraoperative Fluorescence Images Based on Transfer Learning and Convolutional Neural Networks.

To propose a transfer learning based method of tumor segmentation in intraoperative fluorescence images, which will assist surgeons to efficiently and accurately identify the boundary of tumors of interest. We employed transfer learning and deep convolutional neural networks (DCNNs) for tumor segmentation. Specifically, we first pre-trained four networks on the ImageNet dataset to extract low-level features. Subsequently, we fine-tuned these networks on two fluorescence image datasets (ABFM and DTHP) separately to enhance the segmentation performance of fluorescence images. Finally, we tested the trained models on the DTHL dataset. The performance of this approach was compared and evaluated against DCNNs trained end-to-end and the traditional level-set method. The transfer learning-based UNet++ model achieved high segmentation accuracies of 82.17% on the ABFM dataset, 95.61% on the DTHP dataset, and 85.49% on the DTHL test set. For the DTHP dataset, the pre-trained Deeplab v3 + network performed exceptionally well, with a segmentation accuracy of 96.48%. Furthermore, all models achieved segmentation accuracies of over 90% when dealing with the DTHP dataset. To the best of our knowledge, this study explores tumor segmentation on intraoperative fluorescent images for the first time. The results show that compared to traditional methods, deep learning has significant advantages in improving segmentation performance. Transfer learning enables deep learning models to perform better on small-sample fluorescence image data compared to end-to-end training. This discovery provides strong support for surgeons to obtain more reliable and accurate image segmentation results during surgery.

A case of MCA arising from ICA: a case report.

Complete mesocolic excision (CME) and central vascular detachment are very important procedures in surgery for colorectal cancer. Preoperative and intraoperative assessments of the anatomy of major colorectal vessels are necessary to avoid massive bleeding, especially in endoscopic surgery. A case with a rare anomaly in which the middle colic artery (MCA) and ileocolic artery (ICA) had a common trunk is reported. The patient was a 73-year-old woman diagnosed with ascending colon cancer on colonoscopy. Preoperative abdominal contrast-enhanced computed tomography confirmed that the MCA and ICA had a common trunk. She underwent laparoscopic ileocecal resection for the ascending colon cancer with D3 lymph node dissection. Intraoperative indocyanine green fluorescence imaging was conducted. After confirming vessel bifurcation, the ICA was dissected at the distal end of the MCA bifurcation. The patient has been followed as an outpatient, with no signs of recurrence as of 2 years postoperatively. A case of an ascending colon cancer with a unique vascular bifurcation pattern was presented. Preoperative and intraoperative evaluations of the major colorectal vessels are very important for preventing perioperative and postoperative complications.

Application of Laennec extrathecal blockade combined with indocyanine green fluorescence imaging in laparoscopic anatomic hepatectomy.

To investigate the safety and application value of combining Laennec extracapsular occlusion with ICG fluorescence imaging in laparoscopic anatomic hepatectomy. Complete laparoscopic dissection was performed outside the Laennec sheath, blocking Glisson's pedicle of the corresponding liver segment or lobe. An appropriate amount of indocyanine green (ICG) dye was intravenously injected, and the boundary line between the pre-cut liver segment and liver lobe was identified using fluorescence laparoscopy. Complete resection of the liver segment or lobe was performed based on anatomical markers. Clinical data, including operation time, intraoperative blood loss, postoperative hospital stay, and postoperative complications, were collected. A total of 14 cases were included in the study, including seven cases of primary liver cancer, three cases of metastatic liver cancer, three cases of intrahepatic bile duct calculi, and one case of hepatic hemangioma. All 14 patients underwent anatomic hepatectomy under fluorescent laparoscopy, with four cases involving the right liver, seven cases involving the left liver, two cases involving the right anterior lobe, and one case involving the right posterior lobe. Combining laparoscopic follow-up of the Laennec membrane with Glisson outer sheath block and intraoperative ICG fluorescence imaging provides real-time guidance for locating the resection boundaries during anatomic hepatectomy. This approach helps in controlling intraoperative bleeding, reducing operation time, and ensuring high safety. It holds significant value in clinical application.