Blood perfusion assessment by near-infrared fluorescence angiography of epiploic appendages in prevention of anastomotic leakage after laparoscopic intersphincteric resection for ultra-low rectal cancer: a case-matched study.

BACKGROUND: The role of intraoperative near-infrared fluorescence angiography with indocyanine green in reducing anastomotic leakage (AL) has been demonstrated in colorectal surgery, however, its perfusion assessment mode, and efficacy in reducing anastomotic leakage after laparoscopic intersphincteric resection (LsISR) need to be further elucidated. AIM: Aim was to study near-infrared fluorescent angiography to help identify bowel ischemia to reduce AL after LsISR. MATERIAL AND METHODS: A retrospective case-matched study was conducted in one referral center. A total of 556 consecutive patients with ultra-low rectal cancer including 140 patients with fluorescence angiography of epiploic appendages (FAEA)were enrolled. Perfusion assessment by FAEA in the monochrome fluorescence mode. Patients were divided into two groups based on perfusion assessment by FAEA. The primary endpoint was the AL rate within 6 months, and the secondary endpoint was the structural sequelae of anastomotic leakage (SSAL). RESULTS: After matching, the study group (n = 109) and control group (n = 190) were well-balanced. The AL rate in the FAEA group was lower before (3.6% vs. 10.1%, P = 0.026) and after matching (3.7% vs. 10.5%, P = 0.036). Propensity scores matching analysis (OR 0.275, 95% CI 0.035-0.937, P 0.039), inverse probability of treatment weighting (OR 0.814, 95% CI 0.765-0.921, P 0.002), and regression analysis (OR 0.298, 95% CI 0.112-0.790, P = 0.015), showed that FAEA was an independent protector factor for AL. This technique can significantly shorten postoperative hospital stay [9 (6-13) vs. 10 (8-13), P = 0.024] and reduce the risk of SSAL (1.4% vs. 6.0%, P = 0.029). CONCLUSIONS: Perfusion assessment by FAEA can achieve better visualization in LsISR and reduce the incidence of AL, subsequently avoiding SSAL after LsISR.

Indocyanine green uptake by human tumor and non­tumor cell lines and tissue.

Indocyanine green (ICG) is a potential promising dye for a better intraoperative tumor border definition and an improved patient outcome by potentially improving tumor border visualization compared with traditional white light guided surgery. Here, the cellular uptake of ICG in human squamous cell carcinoma (SCC026) and immortalized non-cancer skin (HaCaT) cell lines was evaluated to study the tumor-specific cellular uptake of ICG. The spatial distribution of ICG inside tumor tissue was investigated in tissue sections of head and neck squamous cell carcinoma at a microscopic level. ICG uptake and internalization was observed in living cells after 2.5 h and in the nucleus after 24 h. In dead cells, higher and faster uptake was observed. In the tissue sections, higher ICG signal intensity could be detected in connective tissue and surrounding clusters and blood vessels. In conclusion, no distinct ICG uptake by tumor cells was detected in cancer cell lines and tumor tissue. ICG localization in certain regions of tumor tissue appears to be a result of enhanced tissue permeability and retention, but not specific to tumor cells.

Coadministration of Quercetin and Indocyanine Green via PEGylated Phospholipid Micelles for Augmented Chem-Photothermal Combination Tumor Therapy.

A significant impediment persists in developing multicomponent nanomedicines designed to dismantle the heat shock protein (HSP)-based protective mechanism of malignant tumors during photothermal therapy. Herein, well-defined PEGylated phospholipid micelles were utilized to coencapsulate quercetin (QUE, a natural anticancer agent and potent HSP inhibitor) and indocyanine green (ICG, a photothermal agent) with the aim of achieving synchronized and synergistic drug effects. The subsequent investigations validated that the tailored micellar system effectively enhanced QUE's water solubility and augmented its cellular internalization efficiency. Intriguingly, the compositional PEGylated phospholipids induced extraordinary endoplasmic reticulum stress, thereby sensitizing the tumor cells to QUE. Furthermore, QUE played a crucial role in inhibiting the stress-induced overexpression of HSP70, thereby augmenting the photothermal efficacy of ICG. In systemic applications, the proposed nanotherapeutics exhibited preferential accumulation within tumors and exerted notable tumoricidal effects against 4T1 xenograft tumors under 808 nm near-infrared irradiation, facilitated by prominent near-infrared fluorescence imaging-guided chemo-photothermal therapy. Therefore, our strategy for fabricating multicomponent nanomedicines emerges as a coordinated platform for optimizing antitumor therapeutic efficacy and offers valuable insights for diverse therapeutic modalities.

Innovative ICG Application in Benign Gynaecological Surgery: Enhancing Safety and Precision.

In the context of increased adoption of minimally invasive surgery for benign gynaecological conditions, this study underscores the paramount importance of patient safety. We explored the efficacy of indocyanine green (ICG), a fluorescent dye, in enhancing the visualisation of critical anatomical structures during complex laparoscopic procedures. Our methods involved the direct administration of ICG into the ureters for precise identification and dissection, as well as an innovative vaginal application to delineate the rectovaginal plane in cases with distorted pelvic anatomy. The study presented two cases: a laparoscopic hysterectomy for a multifibroid uterus and a case of advanced endometriosis with rectal involvement. Results indicated that ICG use significantly improved real-time visualisation of the ureters and the rectovaginal plane, which facilitated the surgeries and reduced the cognitive load on surgeons. There were no intraoperative complications, and the postoperative phase showed positive patient outcomes. In conclusion, the application of ICG in these laparoscopic surgeries proved to be a beneficial adjunct, suggesting its potential for broader application in benign gynaecological surgeries. Future research is warranted to explore additional uses of ICG, with a focus on enhancing patient safety and surgical efficacy.

Systematic use of intraureteral indocyanine green: a game changer in endometriosis surgery. A proof-of-concept study.

BACKGROUND: Endometriosis of the distal segment of the uterosacral ligament may lead to a displaced ureter in the surgical field and must be identified before safe disease excision can be carried out. The aim of this study is to investigate the benefit of the systematic use of preoperative intraureteral indocyanine green (ICG) fluorescence injection in patients undergoing endometriosis surgery. METHOD: In this proof-of-concept, monocentric, observational, cohort study data were prospectively collected and retrospectively analyzed. Patients underwent laparoscopic surgery for deep infiltrating endometriosis with suspected ureteral involvement between January 2022 and December 2023. Using the propensity score matching (PSM) in a 1:1 matching ratio, patients who underwent preoperative ICG injection were compared with those who did not in terms of ureterolysis length and duration, and operative time. RESULTS: The mean length of ureterolysis was shorter in the ICG group compared to the non-ICG group (p < 0.001). The ICG group also had shorter ureterolysis duration (p < 0.001) and operative time (p = 0.02). No complications were reported at mean 6.8-month follow-up visit. CONCLUSIONS: The systematic use of intraureteral ICG prior to uterosacral ligaments endometriosis surgery may be safe and could assist in reducing the length of ureterolysis and operative time. Larger prospective studies are needed to confirm our findings.

Intraoperative angiography with indocyanine green, an aid in the diagnosis and treatment of obscure digestive tract bleeding, a case report.

Lower digestive tract bleeding occurs distal to the angle of Treitz. While many cases remit spontaneously; some pose a diagnostic challenge for surgeons. We present the case of a 68-year-old man with unexplained digestive tract bleeding. Despite various diagnostic efforts, the source remained unknown. Faced with the challenge of persistent bleeding and hemodynamic instability, surgery became necessary. During the procedure, intraoperative angiography with indocyanine green was used to facilitate the identification of the bleeding site, revealing a gastrointestinal stromal tumor in the small bowel. Resection was performed with favorable outcomes. Indocyanine green staining has become popular for locating intestinal bleeding during emergency surgeries, aiding surgeons in making precise decisions.

Validation of a semi-quantitative scoring system and workflow for analysis of fluorescence quantification in companion animals.

Significance: Many commercially available near-infrared (NIR) fluorescence imaging systems lack algorithms for real-time quantifiable fluorescence data. Creation of a workflow for clinical assessment and post hoc analysis may provide clinical researchers with a method for intraoperative fluorescence quantification to improve objective outcome measures. Aim: Scoring systems and verified image analysis are employed to determine the amount and intensity of fluorescence within surgical specimens both intra and postoperatively. Approach: Lymph nodes from canine cancer patients were obtained during lymph node extirpation following peritumoral injection of indocyanine green (ICG). First, a semi-quantitative assessment of surface fluorescence was evaluated. Images obtained with a NIR exoscope were analysed to determine fluorescence thresholds and measure fluorescence amount and intensity. Results: Post hoc fluorescence quantification (threshold of Hue = 165-180, Intensity = 30-255) displayed strong agreement with semi-quantitative scoring (k = 0.9734, p < 0.0001). Fluorescence intensity with either threshold of 35-255 or 45-255 were significant predictors of fluorescence and had high sensitivity and specificity (p < 0.05). Fluorescence intensity and quantification had a strong association (p < 0.001). Conclusion: The validation of the semi-quantitative scoring system by image analysis provides a method for objective in situ observation of tissue fluorescence. The utilization of thresholding for ICG fluorescence intensity allows post hoc quantification of fluorescence when not built into the imaging system.

Use of indocyanine green dye for sentinel lymph node mapping in patients with endometrial cancer and a history of iodinated contrast allergy.

Objectives: Sentinel lymph node (SLN) mapping is a surgical technique with high accuracy in detecting metastases while limiting morbidity associated with full lymphadenectomy in endometrial cancer. Cervical injection of indocyanine green (ICG) dye is associated with very high SLN detection rates; however, iodinated contrast allergy has traditionally been viewed as a contraindication to ICG use. The objective of this study was to describe the use of ICG in a population of patients with iodinated contrast allergies undergoing surgical staging for endometrial cancer. Methods: IRB approval was obtained. All patients with clinically early-stage endometrial cancer who underwent minimally invasive surgical staging with SLN mapping with ICG at a single academic institution from 1/1/2017 to 12/31/2020 were identified retrospectively. Patients with reported iodinated contrast allergies prior to surgery were identified. Data were collected through electronic medical record review and compared using descriptive statistics. Results: 820 patients who underwent minimally invasive surgical staging with SLN mapping with ICG were identified, and 25 had documented iodinated contrast allergies. Documented reactions included rash/hives (n = 10, 40 %), anaphylaxis (n = 6, 24 %), shortness of breath (n = 5, 20 %), diarrhea (n = 1, 4 %), and not specified (n = 3, 12 %). A majority (24/25, 96 %) received 4 mg intravenous dexamethasone during induction of general anesthesia as per the institutional enhanced recovery after surgery (ERAS) protocol. No patients experienced allergic reactions or other adverse events after ICG injection. Conclusions: No patients in this cohort demonstrated an adverse reaction after ICG injection for SLN mapping. This study supports the reasonable safety of ICG in patients with contrast allergies, particularly when routine ERAS protocols containing dexamethasone are utilized.

Pay attention to the application of indocyanine green fluorescence imaging technology in laparoscopic liver cancer resection.

Traditional laparoscopic liver cancer resection faces challenges, such as difficulties in tumor localization and accurate marking of liver segments, as well as the inability to provide real-time intraoperative navigation. This approach falls short of meeting the demands for precise and anatomical liver resection. The introduction of fluorescence imaging technology, particularly indocyanine green, has demonstrated significant advantages in visualizing bile ducts, tumor localization, segment staining, microscopic lesion display, margin examination, and lymph node visualization. This technology addresses the inherent limitations of traditional laparoscopy, which lacks direct tactile feedback, and is increasingly becoming the standard in laparoscopic procedures. Guided by fluorescence imaging technology, laparoscopic liver cancer resection is poised to become the predominant technique for liver tumor removal, enhancing the accuracy, safety and efficiency of the procedure.

Complete removal of a cavernous malformation in the dorsal pons, in contact with the expanded transpontine vein: illustrative case.

BACKGROUND: Craniotomy is required for the removal of brainstem cavernous malformations (CMs) with repeated hemorrhage, and this condition is often complicated by an accompanying developmental venous anomaly (DVA). However, a DVA of the brainstem or cerebellum with drainage penetrating the pons is an exceptional finding. OBSERVATIONS: A 57-year-old man presented with double vision. Computed tomography revealed progressive enlargement of the hemorrhage in the dorsal pons. Contrast-enhanced magnetic resonance angiography revealed an expanded transverse vessel penetrating the center of the pons in contact with the CM. Digital subtraction angiography revealed that the DVA, comprising the expanded transpontine vein and some cerebellar medullary veins acting as normal venous drainage, coexisted with the CM. By utilizing the angioarchitecture and intraoperative neuronavigation system data, electrophysiological mapping, and indocyanine green videoangiography, complete removal of the CM was accomplished while preserving the DVA and brain function. LESSONS: This study presents the intraoperative images of an expanded transpontine vein as a DVA, which has never been depicted in a live patient before, accompanied by a CM in the dorsal portion of the pons. https://thejns.org/doi/10.3171/CASE24314.

MIRRORS ICG: Perfusion Assessment Using Indocyanine Green (ICG) Peritoneal Angiography during Robotic Interval Cytoreductive Surgery for Advanced Ovarian Cancer.

Indocyanine green (ICG) is a fluorescent dye used for sentinel lymph node assessment and the assessment of perfusion in skin flaps and bowel anastomoses. ICG binds serum proteins and behaves as a macromolecule in the circulation. Tumour tissue has increased vascular permeability and reduced drainage, causing macromolecules to accumulate within it. MIRRORS ICG is designed to determine whether indocyanine green (ICG) helped identify metastatic deposits in women undergoing robotic interval cytoreductive surgery for advanced-stage (3c+) ovarian cancer. Peritoneal surfaces of the abdominal and pelvic cavity were inspected under white light and near-infrared light (da Vinci Si and Xi Firefly Fluorescence imaging, Intuitive Surgical Inc.) following intravenous injection of 20 mg ICG in sterile water. Visibly abnormal areas were excised and sent to histopathology, noting IGC positivity. In total, 102 biopsies were assessed using ICG. Intravenous ICG assessment following neoadjuvant chemotherapy had a sensitivity of 91.1% (95% CI [82.6-96.4%]), a specificity of 13.0% (95% CI [2.8-33.6%]), a positive predictive value of 78.3% (95% CI [68.4-86.2%]), and a negative predictive value of 30.0% (95% CI [6.7-65.2%]) False-positive samples were seen in 9/20 patients. Psammoma bodies were noted in the histopathology reports of seven of nine of these patients with false-positive results, indicating that a tumour had been present (chemotherapy-treated disease). This study demonstrates the appearance of metastatic peritoneal deposits during robotic cytoreductive surgery following the intravenous administration of ICG in women who have undergone neoadjuvant chemotherapy for stage 3c+ advanced ovarian cancer. A perfusion assessment using indocyanine green (ICG) peritoneal angiography during robotic interval cytoreductive surgery for advanced ovarian cancer did not clinically improve metastatic disease identification in patients with high-volume disease. The use of ICG in patients with excellent response to chemotherapy where few tumour deposits remained shows some promise. The potential of molecular imaging to enhance precision surgery and improve disease identification using the robotic platform is a novel avenue for future research.

Indocyanine green angiography reveals choroidal hypoperfusion in subacute sclerosing panencephalitis (SSPE).

We report the choroidal findings on indocyanine green angiography (ICGA) in two cases of subacute sclerosing panencephalitis (SSPE). The two immunocompetent patients (31-year-old and 30-year-old Asian Indian males) presented with acute-onset rapidly progressing vision loss with findings of necrotizing retinitis involving the central macula. Both patients tested negative for serological evidence of herpes or varicella, and toxoplasma antibodies. The patients demonstrated high serum and cerebrospinal fluid titers of anti-measles antibody (and abnormal electroencephalogram in one patient) leading to the diagnosis of SSPE. ICGA of both patients revealed distinct "dark dots" which showed hypofluorescence in the early and late phases suggestive of choroidal involvement/hypoperfusion. Choroidal involvement in SSPE has not been evaluated before and must be considered in the pathological manifestations of the disease.

Assessing superficial temporal artery-middle cerebral artery anastomosis patency using FLOW 800 hemodynamics.

OBJECTIVE: The objective of this study was to investigate the use of indocyanine green videoangiography with FLOW 800 hemodynamic parameters intraoperatively during superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery to predict patency prior to anastomosis performance. METHODS: A retrospective and exploratory data analysis was conducted using FLOW 800 software prior to anastomosis to assess four regions of interest (ROIs; proximal and distal recipients and adjacent and remote gyri) for four hemodynamic parameters (speed, delay, rise time, and time to peak). Medical records were used to classify patients into flow and no-flow groups based on immediate or perioperative anastomosis patency. Hemodynamic parameters were compared using univariate and multivariate analyses. Principal component analysis was used to identify high risk of no flow (HRnf) and low risk of no flow (LRnf) groups, correlated with prospective angiographic follow-ups. Machine learning models were fitted to predict patency using FLOW 800 features, and the a posteriori effect of complication risk of those features was computed. RESULTS: A total of 39 cases underwent STA-MCA bypass surgery with complete FLOW 800 data collection. Thirty-five cases demonstrated flow after anastomosis revascularization and were compared with 4 cases with no flow after revascularization. Proximal and distal recipient speeds were significantly different between the no-flow and flow groups (proximal: 238.3 ± 120.8 and 138.5 ± 93.6, respectively [p < 0.001]; distal: 241.0 ± 117.0 and 142.1 ± 103.8, respectively [p < 0.05]). Based on principal component analysis, the HRnf group (n = 10) was characterized by high-flow speed (> 75th percentile) in all ROIs, whereas the LRnf group (n = 10) had contrasting patterns. In prospective long-term follow-up, 6 of 9 cases in the HRnf group, including the original no-flow cases, had no or low flow, whereas 8 of 8 cases in the LRnf group maintained robust flow. Machine learning models predicted patency failure with a mean F1 score of 0.930 and consistently relied on proximal recipient speed as the most important feature. Computation of posterior likelihood showed a 95.29% chance of patients having long-term patency given a lower proximal speed. CONCLUSIONS: These results suggest that a high proximal speed measured in the recipient vessel prior to anastomosis can elevate the risk of perioperative no flow and long-term reduction of flow. With an increased dataset size, continued FLOW 800-based ROI metric analysis could be used to guide intraoperative anastomosis site selection prior to anastomosis and predict patency outcome.

Fluorescence imaging in reducing anastomotic leak after left-sided colorectal resections: a systematic review and updated meta-analysis.

BACKGROUND: The objective of this systematic review and meta-analysis was to pool randomized trials of patients undergoing left-sided colorectal anastomosis, comparing the use of fluorescence perfusion imaging versus visual inspection in reducing anastomotic leaks. METHODS: Databases searched included PubMed, Cochrane Library, Scopus, CINHAL (EBSCO), and Google Scholar based on the concepts: randomized, colorectal, anastomotic leak, and fluorescence imaging. The risk of bias was assessed using RoB2 and the certainty of the evidence with the GRADE Pro tool. The analysis used the log odds ratio for dichotomous data with 95% confidence intervals. Back-transformation of the log odds to odds ratio was performed for the summary of findings. All syntheses used the Random-effects model. RESULTS: Six randomized trials were included with 1949 patients and 204 events (leaks). Three trials included exclusively rectal cancer patients, while the other three involved benign and malignant pathologies of the sigmoid and rectum. The use of ostomy and preoperative radiation was variable. None of the studies had a high risk of bias. The pooled odds ratio for anastomotic leak reduction with Indocyanine Green (ICG) fluorescence was 0.586 (95% CI: 0.434-0.792). An absolute reduction of 4.7% in leak rates was observed, with no statistical heterogeneity (I2 = 0; p = 0.529). Due to clinical heterogeneity, the quality of evidence was rated moderate. CONCLUSIONS: The use of ICG is associated with reduced leak rates following left-sided colorectal anastomosis with moderate confidence. ICG may be considered a standard of care given the clinically significant benefit in decreasing anastomotic leaks.

How to increase the success rate in microsurgical free and pedicled flap reconstructions with intraoperative multistep ICG imaging: A case series with 400 consecutive cases.

BACKGROUND: Over the last decade, microsurgical soft-tissue transfer became the gold standard for various reconstructions throughout the body. Continuous improvement of instruments and surgical techniques, such as intraoperative indocyanine green angiography (ICG-A), allowed for a very high success rate. This study aimed to assess and validate the role of a standard intraoperative ICG-A in free and pedicled flap surgery to improve overall outcomes. PATIENTS AND METHODS: From April 2018 to April 2023, 400 consecutive patients who underwent reconstruction using free and pedicled flaps were enrolled. ICG-A was always performed in a free flap after flap elevation, after microsurgical anastomosis, immediately after the flap inset, and after wound closure. In the pedicled flap, the sequential procedure was performed after flap elevation, flap inset, and wound closure. RESULTS: All 400 patients who underwent flap reconstruction using intraoperative ICG-A had an extremely low incidence of necrosis (0.75% partial necrosis among free and pedicled flaps) and reoperation for perfusion-related complications (0.75% due to acute ischemia and 0.50% due to flap congestion). Minor complications, such as hematoma, seroma, wound dehiscence, and wound infections, were managed with a second operation. No flaps were lost, and all patients were successfully treated. CONCLUSIONS: This study showed how systematic multistep ICG-A for intraoperative assessment of free and pedicled flap perfusion can significantly reduce the complication rate, including flap loss and re-exploration surgeries, in a time- and cost-effective manner.

Effect of oxygen generating nanozymes on indocyanine green and IR 820 mediated phototherapy against oral cancer.

The hypoxic environment within a solid tumor is a limitation to the effectiveness of photodynamic therapy. Here, we demonstrate the use of oxygen generating nanozymes (CeO2, Fe3O4, and MnO2) to improve the photodynamic effect. The optimized combination of process parameters for irradiation was obtained using the Box Behnken experimental design. Indocyanine green, IR 820, and their different combinations with oxygen generators were studied for their effect on oral carcinoma. Dynamic light scattering technique showed the average particle size of CeO2, MnO2, and Fe3O4 to be 211 ± 16, and 157 ± 28, 143 ± 19 nm with PDI of 0.23, 0.28 and 0.20 and a zeta potential of -2.6 ± 0.45, -2.4 ± 0.60 and  -6.1 ± 0.23 mV, respectively. The formation of metal oxides was confirmed using UV-visible, FTIR, and X-ray photon spectroscopies. The amount of dissolved oxygen produced by CeO2, MnO2, and Fe3O4 in the presence of H2O2 within 2 min was 1.7 ± 0.15, 1.7 ± 0.16, and 1.4 ± 0.12 mg/l, respectively. Growth inhibition studies in the FaDu oral carcinoma spheroid model showed a significant (P < 0.05) increase in growth reduction from 81 ± 2.9 and 88 ± 2.1% to 97 ± 1.2 and 99 ± 1.0% for ICG and IR 820, respectively, after irradiation (808 nm laser, 1 W/cm2, 5 min) in the presence of CeO2 (25 µg/ml). In conclusion, oxygen-generating nanozymes can improve the photodynamic effect of ICG and IR 820.

Age-related alterations in vortex veins on indocyanine green angiography.

To determine age-related alterations in vortex veins in healthy subjects. A total of 228 healthy subjects (aged 4 to 86 years) were recruited and divided into four groups (G1, <21 years; G2, 21-40 years; G3, 41-60 years; and G4, 61-86 years). The clinical characteristics of the participants were recorded, and parameters including the number of vortex vein roots (NVVR), the central vortex vein diameter (CVVD), the mean root area of the vortex vein (MRAVV), and the weighted mean of the thickest branch diameter (WMTBD) were obtained by marking the vortex veins on indocyanine green angiography (ICGA). The NVVR in the age group over 60 years old was significantly lower than that in other age groups (P < 0.05). The CVVD, MRAVV, and WMTBD of all age groups increased with increasing age (P < 0.05). The NVVR was unevenly distributed among the quadrants (P < 0.001). The proportions of type four vortex veins (complete systems including ampulla) and anastomotic branches of the vortex veins were significantly increased in elderly participants over 50 years of age (P < 0.05). Subfoveal choroidal thickness was significantly correlated with age, NVVR, CVVD and MRAVV (P < 0.05). This is the first study to reveal age-related alterations in vortex veins on ICGA in a healthy population. Aging may lead to partial vortex occlusion and residual vortex dilation. As age increases, anastomotic branches increasingly appear between the originally independent vortex veins. Translational relevance: Aging may lead to partial vortex occlusion and residual vortex dilation.

A Facile Approach to Producing Liposomal J-Aggregates of Indocyanine Green with Diagnostic and Therapeutic Potential.

Liposomal J-Aggregates of Indocyanine Green (L-JA) can serve as a biocompatible and biodegradable nanoparticle for photoacoustic imaging and photothermal therapy. When compared to monomeric IcG, L-JA are characterized by longer circulation, improved photostability, elevated absorption at longer wavelengths, and increased photoacoustic signal generation. However, the documented methods for production of L-JA vary widely. We developed an approach to efficiently form IcG J-aggregates (IcG-JA) directly in liposomes at elevated temperatures. Aggregating within fully formed liposomes ensures particle uniformity and allows for control of J-aggregate size. L-JA have unique properties compared to IcG. L-JA provide significant contrast enhancement in photoacoustic images for up to 24 hours after injection, while IcG and unencapsulated IcG-JA are cleared within an hour. L-JA allow for more accurate photoacoustic-based sO2 estimation and particle tracking compared to IcG. Furthermore, photothermal heating of L-JA with an 852nm laser is demonstrated to be more effective at lower laser powers than conventional 808nm lasers for the first time. The presented technique offers an avenue for formulating a multi-faceted contrast agent for photoacoustic imaging and photothermal therapy that offers significant advantages over other conventional agents.

A Photothermal Polymeric Platform for Efficient and Safe Gene Transfection: When Polyethylenimine Collaborates with Indocyanine Green.

Gene transfection, defined by the delivery of nucleic acids into cellular compartments, stands as a crucial procedure in gene therapy. While branched polyethylenimine (PEI) is widely regarded as the "gold standard" for nonviral vectors, its cationic nature presents several issues, including nonspecific protein adsorption and notable cytotoxicity. Additionally, it often fails to achieve high transfection efficiency, particularly with hard-to-transfect cell types. To overcome these challenges associated with PEI as a vector for plasmid DNA (pDNA), the photothermal agent indocyanine green (ICG) is integrated with PEI and pDNA to form the PEI/ICG/pDNA (PI/pDNA) complex for more efficient and safer gene transfection. The negatively charged ICG serves a dual purpose: neutralizing PEI's excessive positive charges to reduce cytotoxicity and, under near-infrared irradiation, inducing local heating that enhances cell membrane permeability, thus facilitating the uptake of PI/pDNA complexes to boost transfection efficiency. Using pDNA encoding vascular endothelial growth factor as a model, our system shows enhanced transfection efficiency in vitro for hard-to-transfect endothelial cells, leading to improved cell proliferation and migration. Furthermore, in vivo studies reveal the therapeutic potential of this system in accelerating the healing of infected wounds by promoting angiogenesis and reducing inflammation. This approach offers a straightforward and effective method for gene transfection, showing potentials for tissue engineering and cell-based therapies.

[Indocyanine green is an integral part of breast reconstructive surgery using perforator flaps]. / Indotsianin zelenyi ­ neot"emlemaya chast' rekonstruktivnoi khirurgii molochnoi zhelezy s ispol'zovaniem perforantnykh loskutov.

INTRODUCTION: The use of allotransplants for breast reconstruction in surgical stage of the the breast cancer treatment requires tissue perfusion control. The aim of the study was to analyze the effectiveness of using indocyanine green as a drug for determining the perfusion of perforant flaps in breast reconstructive surgery. MATERIAL AND METHODS: A retrospective series of observations of 27 breast reconstructions using autologous transplants is presented: 19 reconstructions with DIEP-flap, 2 with SIEA-flap, 5 with TD-flap; 1 with thoracoepigastric flap. Intraoperative fluorescence angiography was performed using a Stryker device (5900 Optical Court, USA). The intensity of the flap fluorescence was recorded after intravenous bolus injection of 7.5 mg indocyanine green. RESULTS AND DISCUSSION: The optimal time interval from the moment of drug administration to indicative visualization of flap perfusion was 55-60 seconds. In all patients, the area of insufficient blood flow was excised within intensively blood-supplied tissues, according to mapping data with the indocyanine green. With free transplant of flaps postoperative complications during follow-up were recorded in 1 (4.8%) case (marginal necrosis), which is associated with insufficient compression of auxiliary vessels (violation of the dominant vessel contrast technique). With non-free transplant of flaps no complications were detected in the postoperative period. CONCLUSIONS: Indocyanine green allows to prevent necrotic changes and reduce the rehabilitation period. The optimal time for the indicative visualization of flap perfusion was 55-60 seconds. The use of indocyanine green in free transplant of flaps ensured a postoperative period without complications in 20 (95.2%) cases, in non-free flap transplantation - in 6 (100%) cases.