Intraoperative Fluorescence Imaging Research Articles

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.

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.

Intraoperative near-infrared fluorescence visualization of anatomical structures in general surgical and urological practice

Aim: to analyze current literature on the assessment of intraoperative near-infrared fluorescence visualization of anatomical structures in general surgical and urological practice. The experience of using intraoperative near-infrared fluorescence visualization of anatomical structures in general surgical and urological practice is analyzed. The priority areas of the method application are defined, the recent clinical studies in various fields of surgery and urology are reviewed. Conclusions. The method of intraoperative near-infrared fluorescence imaging of anatomical structures with abundant vascularization and for assessing oncological prognosis is the most promising.

Safe and Accurate Laparoscopic Total Gastrectomy for Remnant Gastric Cancer With Severe Adhesions Using Indocyanine Green Fluorescence Imaging: Guidance in Detection of the Accurate Dissection Layer to Avoid Organ Injury.

Laparoscopic total gastrectomy (LTG) for remnant gastric cancer (RGC) requires advanced techniques due to severe postoperative adhesions and anatomic changes. We performed LTG in 2 patients with RGC using intraoperative indocyanine green (ICG) fluorescence imaging. Both cases previously underwent distal gastrectomy with Billroth-I reconstruction for gastric cancer and were subsequently diagnosed with early-stage gastric cancer of the remnant stomach. Indocyanine green (2.5mg/body) was administered intravenously during surgery. The liver and common bile duct were clearly visualized during surgery using near-infrared fluorescence laparoscopy, and the adhesions between the hepatobiliary organs and remnant stomach were safely dissected. Laparoscopic total gastrectomy was successfully performed without complications, and the postoperative course was uneventful in both cases. Intraoperative real-time ICG fluorescence imaging allows clear visualization of the liver and common bile duct and can be useful in LTG for RGC with severe adhesions.

Abstract 2574: The effect of epidermal growth factor expression in detecting oropharyngeal tumors during fluorescence-guided robotic surgery

Abstract Intro: Oropharyngeal squamous cell carcinoma (OPSCC) has been shown to overexpress epidermal growth factor receptor (EGFR), making it a targetable biomarker for fluorescently labeled monoclonal antibodies such as panitumumab-IRDye800, which can be used during fluorescence-guided trans oral robotic surgery (TORS). Although antibody-based fluorescence-guided surgery is being evaluated in several late-stage trials, the use of intraoperative fluorescence imaging for TORS has not been thoroughly explored. We observed that the bi-polar cautery tool[AHM(1] of the TORS robot was auto-florescent and would appear dimmer in the presence of fluorescence from surgically exposed tumor. We aim to characterize the florescence contrast of the tool and tumor to create a rapid qualitative assessment on tumor presence. Methods: During a phase 2 clinical trial evaluating panitmumab-IRDye800 fluorescence-guided TORS of OPSCC, consenting patients (n=12) with biopsy-confirmed OPSCC received 50mg panitumumab-IRDye800 48 hours prior to surgery. Intraoperative fluorescence images were acquired using the onboard fluorescence camera of the Da Vinci Xi robot and post-operation fluorescence exams were conducted by the Pearl and Odyssey Systems (Li-Cor)[BK2]. For each patient, 3 intraoperative views (pre, mid and late resection) showing pathology-confirmed tumor, normal mucosa, and the tool were taken, and several frames from each view were analyzed via ImageJ to calculate mean fluorescence intensity (MFI) in regions of interest. The MFI of tumor and normal muscoa was normalized with MFI of the tool to obtain a standard fluorescence ratio (SFR) per patient[BK3]. A paired t-test was used to compare differences in MFI between the tumor and tool or normal mucosa. Results: The MFI for each time point was graphed for the tool, tumor and normal mucosa. Significant differences were found between tumor and mucosa and tumor and tool for every time point. Tumor/tool SFRs per patient ranged from 2.1 to 60.9, while normal/tool SFRs ranged from 0.4 to 3.1. Receiver operator characteristics curve analyses of tissue-to-tool SFR data showed a sensitivity of 90.9% and a specificity of 96% to identify the presence of tumor. Conclusion: The auto-fluorescent properties of the bipolar cautery tool of the Da Vinci Xi robot can be used for qualitative assessments of tumor presence during fluorescence-guided TORS. Bright fluorescence from the tool relative to surrounding tissue suggests the lack of carcinoma presence, which could confirm the surgeon’s complete resection of OPSCC. Citation Format: Logan Stone, Shilpa M. Rao, Manuel Lora Gonzalez, Diana Lin, Hari Jeyarajan, Carissa M. Thomas, Jason Warram. The effect of epidermal growth factor expression in detecting oropharyngeal tumors during fluorescence-guided robotic surgery [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2574.

A rationally designed nuclei-targeting FAPI 04-based molecular probe with enhanced tumor uptake for PET/CT and fluorescence imaging.

Fibroblast activation protein inhibitor (FAPI) -based probes have been widely studied in the diagnosis of various malignant tumors with positron emission tomography/computed tomography (PET/CT). However, current imaging studies of FAPI-based probes face challenges in rapid clearance rate and potential false-negative results. Furthermore, FAPI has been rarely explored in optical imaging. Considering this, further modifications are imperative to improve the properties of FAPI-based probes to address existing limitations and broaden their application scenarios. In this study, we rationally introduced methylene blue (MB) to FAPIs, thereby imparting nuclei-targeting and fluorescence imaging capabilities to the probes. Furthermore, we evaluated the added value of FAPI-based fluorescence imaging to traditional PET/CT, exploring the potential application of FAPI-based probes in intraoperative fluorescence imaging. A new FAPI-based probe, namely NOTA-FAPI-MB, was designed for both PET/CT and fluorescence imaging by conjugation of MB. The targeting efficacy of the probe was evaluated on fibroblast activation protein (FAP)-transfected cell line and human primary cancer-associated fibroblasts (CAFs). Subsequently, PET/CT and fluorescence imaging were conducted on tumor-bearing mice. The tumor detection and boundary delineation were assessed by fluorescence imaging of tissues from hepatocellular carcinoma (HCC) patients. NOTA-FAPI-MB demonstrated exceptional targeting ability towards FAP-transfected cells and CAFs in comparison to NOTA-FAPI. This benefit arises from the cationic methylene blue (MB) affinity for anionic nucleic acids. PET/CT imaging of tumor-bearing mice revealed significantly higher tumor uptake of [18F]F-NOTA-FAPI-MB (standard uptake value of 2.20 ± 0.31) compared to [18F]F-FDG (standard uptake value of 1.66 ± 0.14). In vivo fluorescence imaging indicated prolonged retention at the tumor site, with retention lasting up to 24h. In addition, the fluorescent probes enabled more precise lesion detection and tumor margin delineation than clinically used indocyanine green (ICG), achieving a 100.0% (6/6) tumor-positive rate for NOTA-FAPI-MB while 33.3% (2/6) for ICG. These findings highlighted the potential of NOTA-FAPI-MB in guiding intraoperative surgical procedures. The NOTA-FAPI-MB was successfully synthesized, in which FAPI and MB simultaneously contributed to the targeting effect. Notably, the nuclear delivery mechanism of the probes improved intracellular retention time and targeting efficacy, broadening the imaging time window for fluorescence imaging. In vivo PET/CT demonstrated favorable performance of NOTA-FAPI-MB compared to [18F]F-FDG. This study highlights the significance of fluorescence imaging as an adjunct technique to PET/CT. Furthermore, the encouraging results obtained from the imaging of human HCC tissues hold promise for the potential application of NOTA-FAPI-MB in intraoperative fluorescent surgery guidance within clinical settings.

Intraoperative indocyanine green fluorescence imaging to predict early hepatic arterial complications after liver transplantation.

In liver transplantation (LT) setting, to propose an innovative intraoperative criterion to judge arterial flow abnormality that may lead to early hepatic arterial occlusion, i.e. thrombosis or stenosis, when left untreated and to carry out re-anastomosis. After liver graft implantation, and after ensuring that there is no abnormality on the Doppler ultrasound (qualitative and quantitative assessment), we intraoperatively injected indocyanine green dye (ICG, 0.01mg/Kg) and we quantified the fluorescence signal at the graft pedicle using ImageJ software. From the obtained images of 89 adult patients transplanted in our center between September 2017 and April 2019, we constructed fluorescence intensity curves of the hepatic arterial signal, and examined their relationship with the occurrence of early hepatic arterial occlusion (thrombosis or stenosis). Early hepatic arterial occlusion occurred in seven patients (7.8%), including three thrombosis and four stenosis. Among various parameters of the flow intensity curve analyzed, the ratio of peak to plateau (RPP) fluorescence intensity and the jagged wave pattern at the plateau phase were closely associated with this dreaded event. By combining RPP at 0.275 and a jagged wave, we best predicted the occurrence of early hepatic arterial occlusion and thrombosis, with sensitivity/specificity of 0.86/0.98 and 1.00/0.94, respectively. Through a simple composite parameter, indocyanine green fluorescence imaging system is an additional and promising intraoperative modality for identifying transplant recipients at high risk of developing early hepatic arterial occlusion. This tool could assist the surgeon in the decision to redo the anastomosis despite normal Doppler ultrasonography.

Multicolor fluorescence microscopy for surgical guidance using a chip-scale imager with a low-NA fiber optic plate and a multi-bandpass interference filter.

In curative-intent cancer surgery, intraoperative fluorescence imaging of both diseased and healthy tissue can help to ensure the successful removal of all gross and microscopic diseases with minimal damage to neighboring critical structures, such as nerves. Current fluorescence-guided surgery (FGS) systems, however, rely on bulky and rigid optics that incur performance-limiting trade-offs between sensitivity and maneuverability. Moreover, many FGS systems are incapable of multiplexed imaging. As a result, clinical FGS is currently limited to millimeter-scale detection of a single fluorescent target. Here, we present a scalable, lens-less fluorescence imaging chip, VISION, capable of sensitive and multiplexed detection within a compact form factor. Central to VISION is a novel optical frontend design combining a low-numerical-aperture fiber optic plate (LNA-FOP) and a multi-bandpass interference filter, which is affixed to a custom CMOS image sensor. The LNA-FOP acts as a planar collimator to improve resolution and compensate for the angle-sensitivity of the interference filter, enabling high-resolution and multiplexed fluorescence imaging without lenses. We show VISION is capable of detecting tumor foci of less than 100 cells at near video framerates and, as proof of principle, can simultaneously visualize both tumors and nerves in ex vivo prostate tissue.

Fluorescent imaging probes for in vivo ovarian cancer targeted detection and surgery.

Ovarian cancer is the most lethal gynecological cancer, with a survival rate of approximately 40% at five years from the diagno. The first-line treatment consists of cytoreductive surgery combined with chemotherapy (platinum- and taxane-based drugs). To date, the main prognostic factor is related to the complete surgical resection of tumor lesions, including occult micrometastases. The presence of minimal residual diseases not detected by visual inspection and palpation during surgery significantly increases the risk of disease relapse. Intraoperative fluorescence imaging systems have the potential to improve surgical outcomes. Fluorescent tracers administered to the patient may support surgeons for better real-time visualization of tumor lesions during cytoreductive procedures. In the last decade, consistent with the discovery of an increasing number of ovarian cancer-specific targets, a wide range of fluorescent agents were identified to be employed for intraoperatively detecting ovarian cancer. Here, we present a collection of fluorescent probes designed and developed for fluorescence-guided ovarian cancer surgery. Original articles published between 2011 and November 2022 focusing on fluorescent probes, currently under preclinical and clinical investigation, were searched in PubMed. The keywords used were targeted detection, ovarian cancer, fluorescent probe, near-infrared fluorescence, fluorescence-guided surgery, and intraoperative imaging. All identified papers were English-language full-text papers, and probes were classified based on the location of the biological target: intracellular, membrane, and extracellular.

Intraoperative indocyanine green imaging as an adjunctive technique to reduce any circumflex artery damage during mitral valve surgery: a feasibility study.

Iatrogenic injuries to the circumflex coronary artery during mitral valve surgery are probably underestimated (reported rates of 0.3-1.8%). This complication arises from the artery's close proximity to the mitral annulus, particularly at the anterolateral commissure. The study aimed to assess this risk in a patient group prone to such injury. The surgical procedure utilized a minimally invasive approach and indocyanine green-based fluorescence imaging. This technique allows a real-time visualization of the circumflex artery, aiding precise placement of annular sutures and minimizing the risk of injury. The method, applied in 6 patients, integrates preoperative assessments with intraoperative fluorescence imaging, ensuring accurate arterial depiction and preventing iatrogenic damage. The study highlights the safety and efficacy of fluorescence imaging, especially in identifying vessel anomalies, indicating potential applications in various cardiac procedures.

Optical precision in pancreatic cancer surgery: novel targeted fluorescent probe - cRGD-ZW800-1 for intraoperative near-infrared fluorescence imaging – a phase II feasibility trial

Optical precision in pancreatic cancer surgery: novel targeted fluorescent probe - cRGD-ZW800-1 for intraoperative near-infrared fluorescence imaging – a phase II feasibility trial

Treatment strategy for lymph node metastasis of hepatocellular carcinoma using an ICG navigation system: a case report

BackgroundSince indocyanine green (ICG) accumulates selectively in hepatocellular carcinoma (HCC) cells, it can be used to detect metastatic lesions. Lymph node metastasis of HCC is rarely observed, both simultaneously and metachronously. Therefore, it is sometimes difficult to identify metachronous lymph nodes during salvage surgery because of prior surgery. Herein, we report a case in which lymph node metastasis of HCC was successfully resected using an ICG navigation system.Case presentationThe patient was a 62-year-old man who had undergone radical liver resection for HCC 8 years ago. During surveillance, contrast-enhanced computed tomography (CT) revealed a mass in the hepatic hilum. Various diagnostic modalities suggested that the patient had a solitary metastatic lymph node of HCC, and extirpation of the tumor was planned. Intraoperative ICG fluorescence imaging allowed surgeons to clearly identify the target lesion. Histopathologically, the tumor was confirmed to be a lymph node metastasis of HCC. The patient’s postoperative course was uneventful, and he remains alive without recurrence 2 years after the second surgery.ConclusionIntraoperative navigation surgery by ICG fluorescence imaging was useful for the safe resection of extrahepatic metastasis of HCC in a complicated situation.

Intraoperative Fluorescence Imaging During Robotic Pancreatoduodenectomy to Detect Suture-Induced Hypoperfusion of the Pancreatic Stump as a Predictor of Postoperative Pancreatic Fistula (FLUOPAN): Prospective Proof-of-concept Study.

A potential downside of robotic pancreatoduodenectomy (RPD) is the lack of tactile feedback when tying sutures, which could be especially perilous during pancreatic anastomosis. Near-infrared fluorescence imaging with indocyanine green (NIRF-ICG) could detect transpancreatic-suture-induced hypoperfusion of the pancreatic stump during RPD, which may be related to postoperative pancreatic fistula (POPF) grade B/C, but studies are lacking. This prospective study included 37 patients undergoing RPD to assess the relation between pancreatic stump hypoperfusion as objectified with NIRF-ICG using Firefly and the rate of POPF grade B/C. In 27 patients, NIRF-ICG was performed after tying down the transpancreatic U-sutures. In 10 'negative control' patients, NIRF-ICG was performed before tying these sutures. Pancreatic stump hypoperfusion was detected using NIRF-ICG in 9/27 patients (33%) during RPD. Hypoperfusion was associated with POPF grade B/C (67% [6/9 patients] versus 17% [3/18 patients], P = 0.026). No hypoperfusion was objectified in 10 'negative controls'. Transpancreatic-suture-induced pancreatic stump hypoperfusion can be detected using NIRF-ICG during RPD and was associated with POPF grade B/C. Surgeons could use NIRF-ICG to adapt their suturing approach during robotic pancreatico-jejunostomy. Further larger prospective studies are needed to validate the association between transpancreatic-suture-induced hypoperfusion and POPF.

The GEM-handle as convenient labeling strategy for bimodal single-domain antibody-based tracers carrying 99mTc and a near-infrared fluorescent dye for intra-operative decision-making.

Intra-operative fluorescence imaging has demonstrated its ability to improve tumor lesion identification. However, the limited tissue penetration of the fluorescent signals hinders the detection of deep-lying or occult lesions. Integrating fluorescence imaging with SPECT and/or intra-operative gamma-probing synergistically combines the deep tissue penetration of gamma rays for tumor localization with the precision of fluorescence imaging for precise tumor resection. In this study, we detail the use of a genetically encoded multifunctional handle, henceforth referred to as a GEM-handle, for the development of fluorescent/radioactive bimodal single-domain antibody (sdAb)-based tracers. A sdAb that targets the urokinase plasminogen activator receptor (uPAR) was engineered to carry a GEM-handle containing a carboxy-terminal hexahistidine-tag and cysteine-tag. A two-step labeling strategy was optimized and applied to site-specifically label IRDye800CW and 99mTc to the sdAb. Bimodal labeling of the sdAbs proved straightforward and successful. 99mTc activity was however restricted to 18.5 MBq per nmol fluorescently-labeled sdAb to prevent radiobleaching of IRDye800CW without impeding SPECT/CT imaging. Subsequently, the in vivo biodistribution and tumor-targeting capacity of the bimodal tracer were evaluated in uPAR-positive tumor-bearing mice using SPECT/CT and fluorescence imaging. The bimodal sdAb showed expected renal background signals due to tracer clearance, along with slightly elevated non-specific liver signals. Four hours post-injection, both SPECT/CT and fluorescent images achieved satisfactory tumor uptake and contrast, with significantly higher values observed for the anti-uPAR bimodal sdAb compared to a control non-targeting sdAb. In conclusion, the GEM-handle is a convenient method for designing and producing bimodal sdAb-based tracers with adequate in vivo characteristics.

A case of lymphatic flow evaluation using indocyanine green fluorescence imaging for recurrence of anastomotic site after laparoscopic right hemicolectomy

BackgroundAnastomotic recurrence of colorectal cancer is rare, but reoperation improves prognosis. However, there is no clear evidence regarding the extent of dissection, and there are few reports on the details of surgery. We used intraoperative lymphatic flow imaging with indocyanine green (ICG) fluorescence as a reference to determine the range of additional resection.Case presentationThe patient was a 75-year-old man who underwent laparoscopic right hemicolectomy and extracorporeal functional terminal anastomosis for ascending colon cancer 4 years ago. Histopathological examination revealed a well-differentiated tubular adenocarcinoma, T4aN0M0, pathological stageIIB. During follow-up, anemia was observed, and colonoscopy indicated anastomotic recurrence, so additional laparoscopic resection was performed. Intraoperatively, ICG was injected into the anastomotic site, and the operation proceeded under near-infrared light observation. Lymphatic vessels along the middle colonic artery were visualized down to the root of the vessel. Using this as an indicator, the vessel was ligated from the root. Using the fact that the lymphatic vessels were also depicted in the small intestinal mesentery on the oral side of the anastomosis as an indicator, the small intestine and mesentery were resected about 7 cm from the anastomosis.ConclusionsThe optimal surgical approach for anastomotic recurrence of colorectal cancer has not been defined. Intraoperative ICG fluorescence imaging can provide images of lymphatic flow from the site of recurrence and may be an indicator of lymph node dissection in the case of anastomotic recurrence.

Advancements in Intraoperative Near-Infrared Fluorescence Imaging for Accurate Tumor Resection: A Promising Technique for Improved Surgical Outcomes and Patient Survival.

Clear surgical margins for solid tumor resection are essential for preventing cancer recurrence and improving overall patient survival. Complete resection of tumors is often limited by a surgeon's ability to accurately locate malignant tissues and differentiate them from healthy tissue. Therefore, techniques or imaging modalities are required that would ease the identification and resection of tumors by real-time intraoperative visualization of tumors. Although conventional imaging techniques such as positron emission tomography (PET), computed tomography (CT), magnetic resonance imaging (MRI), or radiography play an essential role in preoperative diagnostics, these cannot be utilized in intraoperative tumor detection due to their large size, high cost, long imaging time, and lack of cancer specificity. The inception of several imaging techniques has paved the way to intraoperative tumor margin detection with a high degree of sensitivity and specificity. Particularly, molecular imaging using near-infrared fluorescence (NIRF) based nanoprobes provides superior imaging quality due to high signal-to-noise ratio, deep penetration to tissues, and low autofluorescence, enabling accurate tumor resection and improved survival rates. In this review, we discuss the recent developments in imaging technologies, specifically focusing on NIRF nanoprobes that aid in highly specific intraoperative surgeries with real-time recognition of tumor margins.

Use of Near-Infrared Fluorescence Techniques in Minimally Invasive Surgery for Colorectal Liver Metastases.

Colorectal liver metastases (CRLM) afflict a significant proportion of patients with colorectal cancer (CRC), ranging from 25% to 30% of patients throughout the course of the disease. In recent years, there has been a surge of interest in the application of near-infrared fluorescence (NIRF) imaging as an intraoperative imaging technique for liver surgery. The utilisation of NIRF-guided liver surgery, facilitated by the administration of fluorescent dye indocyanine green (ICG), has gained traction in numerous medical institutions worldwide. This innovative approach aims to enhance lesion differentiation and provide valuable guidance for surgical margins. The use of ICG, particularly in minimally invasive surgery, has the potential to improve lesion detection rates, increase the likelihood of achieving R0 resection, and enable anatomically guided resections. However, it is important to acknowledge the limitations of ICG, such as its low specificity. Consequently, there has been a growing demand for the development of tumour-specific fluorescent probes and the advancement of camera systems, which are expected to address these concerns and further refine the accuracy and reliability of intraoperative fluorescence imaging in liver surgery. While NIRF imaging has been extensively studied in patients with CRLM, it is worth noting that a significant proportion of published research has predominantly focused on the detection of hepatocellular carcinoma (HCC). In this study, we present a comprehensive literature review of the existing literature pertaining to intraoperative fluorescence imaging in minimally invasive surgery for CRLM. Moreover, our analysis places specific emphasis on the techniques employed in liver resection using ICG, with a focus on tumour detection in minimal invasive surgery (MIS). Additionally, we delve into recent developments in this field and offer insights into future perspectives for further advancements.