Blood flow assessment of gastric tube with indocyanine green fluorescence angiography and postoperative endoscopy during esophagectomy: indocyanine green enhancement time indicated congestion.

BACKGROUND: During esophagectomy, evaluation of blood supply to the gastric tube is critically important to estimate and avoid anastomotic complications. This retrospective study investigated the relationship between indocyanine green (ICG) fluorescence angiography during esophagectomy and postoperative endoscopy findings, especially mucosal color change. METHODS: This study retrospectively collected data from 86 patients who underwent subtotal esophagectomy and reconstruction using a gastric tube for esophageal cancer at the Tokyo Medical and Dental University between 2017 and 2020. The flow speed of ICG fluorescence in the gastric tube was evaluated during the operation. Additionally, the main root of ICG enhancement and pattern of ICG distribution in the gastric tube were evaluated. On postoperative day 1 (POD1), the change in the mucosal color to white, thought to reflect ischemia, or black, thought to reflect congestion of the proximal gastric tube, was evaluated. The correlations between these factors, clinical parameters, and surgical outcomes were evaluated. Univariate and multivariate analyses used logistic regression to identify the risk factors affecting mucosal color change. RESULTS: Multivariate analyses revealed that the only independent significant predictor of mucosal congestion on POD1 was the ICG enhancement time of the right gastric tube tip (odds ratio, 14.49; 95% confidential interval, 2.41-87.24; P = 0.004). CONCLUSIONS: This study indicated that the ICG enhancement time is related to venous malperfusion and congestion rather than arterial malperfusion and ischemia.

New concept in selecting blue dye injection site effect on clinical outcome of early-stage breast cancer patients: a retrospective cohort.

BACKGROUND: Clinico-anatomical review and pilot studies demonstrated that intraparenchymal injection at any site, even those not containing the index lesion, or periareolar injections should provide concordant outcomes to peritumoral injections. METHOD: This was a single-center retrospective cohort at King Chulalongkorn Memorial Hospital. The electronic medical records of patients were characterized into conventional and new injection concept groups. The inclusion criteria were patients who had either a mastectomy or BCS along with SLNB. We excluded patients who underwent ALND, received neoadjuvant therapy, or had non-invasive breast cancer. The primary outcome was the 5-year rate of breast cancer regional recurrence. Additionally, we reported on the re-operation rate, disease-free period, distant disease-free period, mortality rate, and recurrence rates both locoregional and systemic. Recurrences were identified through clinical assessments and imaging. SURGICAL TECHNIQUE: 3 ml of 1%isosulfan blue dye was injected, with the injection site varying according to the specific concept being applied. In cases of SSM and NSM following the new concept, the blue dye was injected at non-periareolar and non-peritumoral sites. After the injection, a 10-minute interval was observed without massaging the injection site. Following this interval, an incision was made to access the SLNs, which were subsequently identified, excised, and sent for either frozen section analysis or permanent section examination. RESULT: There were no significant differences in DFS, DDFS or BCSS between the two groups (p = 0.832, 0.712, 0.157). Although the re-operation rate in the NI group was approximately half that of the CI group, this difference was not statistically significant (p = 0.355). CONCLUSION: Our study suggests that tailoring isosulfan blue dye injection site based on operation type rather than tumor location is safe and effective approach for SLN localization in early-stage breast cancer. However, this study has limitations, including being a single-center study with low recurrence and death cases. Future studies should aim to increase the sample size and follow-up period.

Role of sentinel lymph node biopsy with indocyanine green and site of injection in endometrial cancer.

PURPOSE OF REVIEW: The aim of the present narrative review is to summarize the state of art on sentinel lymph node biopsy (SLNB) in endometrial cancer, with a special focus on indocyanine green (ICG) as adopted tracer. RECENT FINDINGS: Over the years, the surgical nodal staging in patients with endometrial cancer has been intensively investigated. Traditionally, systematic pelvic and para-aortic lymphadenectomy represented the gold standard surgical treatment to assess nodal involvement of the tumor. Through the last two decades, SLNB has gradually replaced lymphadenectomy as a more targeted procedure. A great heterogeneity of tracers and injection techniques have been proposed to perform SLNB. However, no universally accepted recommendations are still available. SUMMARY: SLNB has nowadays almost replaced pelvic lymphadenectomy in low-risk endometrial cancers, offering a better safety profile while being related to a comparable nodal involvement sensitivity. Currently, ICG is considered to be the most used tracer among others. Different injection sites have been proposed, with different detection features. While ICG cervical injection is nowadays the suggested technique for SLNB, noncervical injection techniques, such as hysteroscopic and combined procedures, seem to have a better accuracy in para-aortic nodal assessment, which have a role in high-risk endometrial cancers.

[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.

[Experience of indocyanine green use in acute calculous cholecystitis]. / Opyt primeneniya indotsianina zelenogo pri ostrom kal'kuleznom kholetsistite.

OBJECTIVE: To assess the safety and effectiveness of the indocyanine green use in acute cholecystitis for identification of anatomical variants of the biliary tree; prevention and timely detection of intraoperative complications. MATERIAL AND METHODS: The medication of indocyanine green made by OOO «Ferment¼ domestic manufacturer was used. The drug dose from 2.5 mg to 10 mg was applied according to studied materials (8). Time of the surgery beginning was from 2 to 6 hours after intravenous injection of aqueous solution, respectively. In addition, it has been established that the optimal drug dose is 5 mg. The surgery should be performed not earlier than 3 hours after, but no later than 6 hours. This allows to achieve the most comfortable fluorescence of the extrahepatic biliary tract. The drug concentration in the liver cells decreases by this time and increases in the biliary tract. It is not always possible to perform the operation strictly within the specified time limit considering the urgency of the surgical intervention. In this connection, the surgery was carried out not earlier than 3 hours after the drug injection, but not later than 6 hours. Endoscopic equipment with the ability to display near-infrared fluorescence was used. A laser light source with a wavelength of 820 nm in the Arthrex imaging system with 4K resolution as well as the Olympus imaging system with HD resolution were used for fluorescence excitation. RESULTS: The implementation of intraoperative fluorescent navigation with indocyanine green contributes to the improvement of safety and effectiveness of surgical treatment through visualization of topography and identification of anatomical variants of the biliary tree; possibilities of prevention and timely detection of intraoperative complications. The use of indocyanine green allows to intraoperatively reveal atypical location and different variations of the extrahepatic biliary tract.

Indocyanine green near-infrared fluorescence bowel perfusion assessment to prevent anastomotic leakage in minimally invasive colorectal surgery (AVOID): a multicentre, randomised, controlled, phase 3 trial.

BACKGROUND: Anastomotic leakage is a severe postoperative complication in colorectal surgery and compromised bowel perfusion is considered a major contributing factor. Conventional methods to assess bowel perfusion have a low predictive value for anastomotic leakage. We therefore aimed to evaluate the efficacy of real-time assessment with near-infrared (NIR) fluorescence imaging with indocyanine green (ICG) in the prevention of anastomotic leakage. METHODS: This multicentre, randomised, controlled, phase 3 trial was done in eight hospitals in the Netherlands. We included adults (aged >18 years) who were scheduled for laparoscopic or robotic colorectal surgery (with planned primary anastomosis) for benign and malignant diseases. Preoperatively, patients were randomly assigned (1:1) to fluorescence-guided bowel anastomosis (FGBA) or conventional bowel anastomosis (CBA) by variable block randomisation (block sizes 4, 6, and 8) and stratified by site. The operating surgeon and investigators analysing the data were not masked to group assignment. Patients were unmasked after the surgical procedure or after study end. In the FGBA group, surgeons marked anastomosis levels per conventional perfusion assessment and then administered 5 mg of ICG by 2 mL intravenous bolus. They assessed bowel perfusion using NIR fluorescence imaging and adjusted (or kept) transection lines accordingly. Only conventional methods for bowel perfusion assessment were used in the CBA group. The primary outcome was the difference in the rate of clinically relevant anastomotic leakage (ie, requiring active therapeutic intervention but manageable without reoperation [grade B] or requiring reoperation [grade C], per the International Study Group of Rectal Cancer) between the FGBA group and the CBA group within 90 days post-surgery. The primary outcome and safety were assessed in the intention-to-treat population. This study was registered with ToetsingOnline.nl (NL7502) and ClinicalTrials.gov (NCT04712032) and is complete. FINDINGS: Between July 2, 2020, and Feb 21, 2023, 982 patients were enrolled, of whom 490 were assigned to FGBA and 492 were assigned to CBA. After excluding 51 patients, the intention-to-treat population comprised 931 (463 assigned FGBA and 468 assigned CBA). Patients had a median age of 68·0 years (IQR 59·0-75·0) and 485 (52%) were male and 446 (48%) were female. Ethnicity data were not available. The overall 90-day rate of clinically relevant anastomotic leakage was not significantly different between the FGBA group (32 [7%] of 463 patients) and the CBA group (42 [9%] of 468 patients; relative risk 0·77 [95% CI 0·50-1·20]; p=0·24). No adverse events related to ICG use were observed. 313 serious adverse events in 229 (25%) patients were at 90-day follow-up (159 serious adverse events in 113 [24%] patients in the FGBA group and 154 serious adverse events in 116 [25%] patients in the CBA group). 18 (2%) people died by 90 days (ten in the FGBA group and eight in the CBA group). INTERPRETATION: ICG NIR fluorescence imaging did not reduce 90-day anastomotic leakage rates in this trial across all types of colorectal surgeries. Further research should be done in subgroups, such as rectosigmoid resections, for which evidence suggests ICG NIR might be beneficial. FUNDING: Olympus Medical, Diagnostic Green, and Intuitive Foundation.

Understanding healing complications in implant-based breast reconstruction using novel metrics for indocyanine green angiography.

INTRODUCTION: Indocyanine green (ICG) angiography for the intraoperative evaluation of tissue perfusion is commonly used in implant-based breast reconstruction (IBR). The assessment of ICG images depends on the surgeon's interpretation and is qualitative or semiqualitative in nature. To quantify ICG metrics, this study aimed to apply a novel assessment of fill-rate dynamics to predict wound-healing complications and provide pragmatic assessment tools in IBR. METHODS: This was a retrospective cohort study of patients who underwent IBR with ICG using the photodynamic eye (PDE-Neo II) qualitative imaging system between April 2021 and September 2023. ICG recordings were reviewed to quantify the relative surface area and fluorescence intensity of visual perfusion deficits using ImageJ. The primary outcome was the incidence of wound-healing complications. t-tests and logistic regression were performed for statistical testing. RESULTS: A total of 112 patients (201 breasts) were included. The incidence of wound-healing complications was 12.9%. A higher relative surface area of ischemic regions was significantly associated with wound-healing complications (3.3% vs. 0.90%; p = 0.001). The rate of change in the surface area of ischemic regions was significantly associated with wound-healing complications (0.35% per second vs. 1.29% per second; p = 0.003%). On average, the duration of transient ischemic areas was significantly longer in breasts with wound-healing complications (46.0 s vs. 36.0 s, p = 0.01). CONCLUSION: A transient ischemic area of > 5% of the breast and/or failure to resolve transient ischemic areas after 60 s may predict wound-healing complications and inform surgical reconstructive decision-making in IBR.

Quantitative analysis of peri-intestinal lymph node metastasis using indocyanine green fluorescence imaging technology.

We evaluated the efficacy of indocyanine green fluorescence imaging compared to that of traditional nanocarbon dyes in assessing peri-intestinal lymph node metastasis in patients with colorectal cancer, which is a key prognostic factor. The relationship between indocyanine green fluorescence imaging and histopathological outcomes in patients with colon cancer has also been explored. A retrospective analysis was conducted on 30 patients with colon cancer (from May to October 2023) confirmed by surgical pathology. Tumors were marked with indocyanine green (ICG) or nanocarbon via colonoscopy 16 to 24 hours before surgery. Within 15 minutes after surgery, peri-intestinal lymph node fluorescence imaging and hematoxylin and eosin staining were used to assess the distribution of cancer foci. The correlation between cancer foci distribution, fluorescence intensity, and area under the receiver operating characteristic curve was measured. Among 243 metastatic lymph nodes from 30 patients, 18 were found. After the patients were divided into metastatic and nonmetastatic groups, significant differences in tumor differentiation and stage were noted (P < .001). The fluorescence intensity was strongly correlated with the presence and proportion of metastasis (area under the receiver operating characteristic curve = 0.931), whereas nanocarbon staining showed no significant correlation (P = .81). All P values were two-sided, with P < .05 indicating statistical significance. Lymph nodes with malignant intestinal tumor metastasis displayed weaker ICG fluorescence than did nonmetastatic nodes. Combining ICG and nanocarbon staining techniques enhances intraoperative lymph node dissection and postoperative analysis, indicating their potential utility in colorectal cancer surgery.

Indocyanine green fluorescence perfusion testing in robot-assisted hepatic arterial infusion pump placement.

BACKGROUND: Hepatic arterial infusion pump (HAIP) treatment is a technique used to treat liver localized malignancy with intra-arterial chemotherapy. Methylene blue is generally administered to verify hepatic perfusion and exclude inadvertent extrahepatic perfusion. The use of indocyanine green dye (ICG) combined with near-infrared (NIR) fluorescence imaging during robot-assisted HAIP placement may be an attractive alternative by providing high contrast without blue discoloration of the operative field. METHODS: Data was collected retrospectively from 2 centers in the Netherlands. Intraoperative perfusion of the liver segments and extrahepatic perfusion were assessed using ICG/NIR as well as methylene blue on video imaging and correlated to postoperative 99 m-Tc perfusion scintigraphy. RESULTS: 13 patients underwent robot-assisted surgery for HAIP placement; median length of stay was 4 days, complications occurred in 4 patients. Hepatic perfusion showed identical patterns when ICG was compared with methylene blue. In 1 patient, additional extrahepatic perfusion was found using ICG, leading to further vessel ligation. Intraoperative ICG perfusion was concordant with 99 m-Tc perfusion scintigraphy. DISCUSSION: Liver and extrahepatic perfusion determined by ICG fluorescence imaging is concordant with blue dye perfusion and 99 m-Tc perfusion scintigraphy. Therefore, ICG fluorescence imaging is deemed a safe and reliable technique for perfusion testing during robot-assisted HAIP placement.

Future of sentinel node biopsy in ovarian cancer.

PURPOSE OF REVIEW: The rationale on the use of sentinel lymph node (SLN) biopsy in the surgical staging of apparent early-stage ovarian cancer (OC) is supported by the fact that diagnostic and prognostic role of systematic staging lymphadenectomy has been determined but its therapeutic significance is still matter of controversy. Moreover, SLN biopsy represents an option to decrease intra- and postoperative morbidity. The present review aims to provide an overview on the current and future role of SLN in OC. RECENT FINDINGS: Most recent evidence shows that the overall mean per patient SLN detection rate in case of indocyanine green (ICG) alone was 58.6% compared with 95% in case of ICG + technetium, and with 52.9% in case of technetium alone or in combination with blue dye ( P  < 0.001). Site of injection has been reported to be in both ovarian ligaments in majority of studies (utero-ovarian ligament and infundibulo-pelvic ligament), before or after ovarian mass removal, at time of primary or re-staging surgery and by minimally invasive or open approach. Cervical injection has been recently proposed to replace utero-ovarian injection. SLN detection rate in patients with confirmed ovarian malignancy varied across different studies ranging between 9.1% and 91.3% for the injection in the utero-ovarian ligament and migration to pelvic lymph nodes and between 27.3% and 100% for the injection in the infundibulo-pelvic ligament and migration to para-aortic lymph nodes. No intra- or postoperative complication could be attributed directly to SLN biopsy. The sensitivity and the accuracy of SLN in detecting lymphatic metastasis ranged between 73.3-100% and 96-100%, respectively. In up to 40% of positive SLNs, largest metastatic deposit was classified as micro-metastasis or isolated tumor cells, which would have been missed without ultrastaging protocol. SUMMARY: SLN biopsy represents a promising tool to assess lymph node status in apparent early-stage OC. The type and volume of injected tracer need to be considered as appear to affect SLN detection rate. Ultrastaging protocol is essential to detect low volume metastasis. Sensitivity and accuracy of SLN biopsy are encouraging, providing tracer injection in both uterine and ovarian ligaments.

ACUTE POSTERIOR MULTIFOCAL PLACOID PIGMENT EPITHELIOPATHY AND PLACOID VARIANT DISEASES MASQUERADING AS AGE-RELATED MACULAR DEGENERATION IN THE ELDERLY: A Case Series.

PURPOSE: To report eight cases of acute posterior multifocal placoid pigment epitheliopathy (APMPPE) or persistent placoid maculopathy (PPM) initially masquerading as age-related macular degeneration in elderly individuals. METHODS: APMPPE or PPM eyes in patients above age 55 years with macular retinal pigment epithelium disruption including drusenoid lesions on macular examination and/or with multimodal imaging were included. At least one method of multimodal imaging including fluorescein angiography (FA), indocyanine green angiography, optical coherence tomography (OCT), and OCT angiography (OCTA) was performed in all eyes for diagnosis and to monitor for macular neovascularization. RESULTS: Eight elderly male patients presented with vision loss and were all initially diagnosed with non-neovascular or neovascular age-related macular degeneration. With the aid of multimodal retinal imaging, a final diagnosis of either APMPPE or PPM was rendered. With FA and indocyanine green angiography, choroidal hypoperfusion was detected in all but one eye. With OCT, the angular sign of Henle fiber layer hyperreflectivity was identified in >50% of eyes. With OCTA, inner choroidal flow deficits were detected in all eyes. Macular neovascularization requiring anti-vascular endothelial growth factor injection therapy complicated three of eight cases. CONCLUSION: Both APMPPE and PPM may develop in elderly individuals and may masquerade as age-related macular degeneration on presentation. Multimodal imaging including FA, indocyanine green angiography, and OCTA are important diagnostic modalities to assess for inner choroidal hypoperfusion to arrive at an accurate diagnosis and to detect macular neovascularization, which frequently complicates APMPPE and PPM. In these patients, serial anti-vascular endothelial growth factor intravitreal injections are essential in treating macular neovascularization and in preventing significant vision loss.

Role of indocyanine green-guided near-infrared fluorescence imaging in identification of the cause of neonatal cholestasis.

To evaluate the efficacy and safety of indocyanine green (ICG)-guided near-infrared fluorescence (NIRF) imaging during surgery to diagnose the cause of neonatal cholestasis (NC). Data on NC patients who underwent both NIRF with ICG and conventional laparoscopic bile duct exploration (the gold standard) at our institute from January 2022 to December 2022 were retrospectively analyzed. The patients' baseline characteristics and liver function outcomes were collected and analyzed, and the diagnostic consistency was compared between the 2 methods. In total, 16 NC patients were included in the study, comprising 8 (50%) male and 8 (50%) female patients, ranging in age from 42 to 93 days, with a median age of 54.4 ±â€…21 days. During surgery, all the patients underwent NIRF with ICG, followed by conventional laparoscopic bile duct exploration. Finally, 15 of the patients were diagnosed with biliary atresia (BA) (1 with type-I BA, and 14 with type-II BA). The other patient was diagnosed with cholestasis. The diagnostic results from fluorescence imaging with ICG were consistent with those from conventional laparoscopic bile duct exploration. ICG-guided NIRF is associated with an easy operation, less trauma, and good safety. Also, its diagnostic accuracy is similar to conventional laparoscopic bile duct exploration.

Efficacy and safety evaluation of Monoblue Dual View and Monoblue ILM View vital stains during vitrectomy surgery.

PURPOSE: To compare the staining properties of Monoblue inner limiting membrane (ILM) View and Monoblue DUAL View (study products) vital stains during vitrectomy surgery to those of ILM Blue or Membrane Blue Dual (control products). METHODS: In this study, 105 patients were included in the Ophthalmic Clinic of the University Hospitals Leuven from September 2021 to April 2022. For prospective data collection in this study, patients were randomized between a control group (ILM Blue or Membrane Blue Dual, manufactured and commercialized by DORC®) and a study group (Monoblue ILM View or Monoblue DUAL View, manufactured and commercialized by Arcadophta®-BVI®). For retrospective data collection, patients were divided into similar surgery groups. Efficacy was analyzed using a binary subjective evaluation of the visualization of stained membranes during vitrectomy. The rate and severity of potential adverse events related to the study products were tracked, allowing both treatment groups to be compared with the corresponding control groups (ILM Blue and Membrane Blue Dual). RESULTS: Based on the results and findings, none of the comparisons (primary outcomes) were statistically significant, showing similar efficacy of the dyes used. The study products were found to be safe in this study since no serious adverse events were reported. CONCLUSIONS: The present findings indicate that the Monoblue ILM View and Monoblue DUAL View dyes can safely be used during vitrectomy to stain the ILM and/or epiretinal membrane (ERM) when removal is needed.

A simple, ingenious approach for intra-operative detection of coronary cameral fistula.

A 56-year-old female presented to us with rheumatic mitral stenosis with a left atrial clot. We found one coronary cameral fistula on the coronary angiography from the posterior left ventricular branch to the left ventricle. She was taken up for surgical mitral valve replacement and clot removal. A residual coronary fistula may increase the risk of infective endocarditis, especially in the presence of mechanical prosthesis. Henceforth, intra-operatively, we used the methylene blue dye injection as an easy technique to detect and safely close the coronary fistula from inside the left ventricular chamber. She recovered smoothly with a successful outcome.

Dose optimization of second window indocyanine green in meningioma patients.

OBJECTIVE: Surgery 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. METHODS: Patients 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/DISCUSSION: In 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. CONCLUSION: This 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.

Real time organ hypoperfusion detection using Indocyanine Green in a piglet model.

BACKGROUND: Preserving sufficient oxygen supply to the tissue is fundamental for maintaining organ function. However, our ability to identify those at risk and promptly recognize tissue hypoperfusion during abdominal surgery is limited. To address this problem, we aimed to develop a new method of perfusion monitoring that can be used during surgical procedures and aid surgeons' decision-making. METHODS: In this experimental porcine study, thirteen subjects were randomly assigned one organ of interest [stomach (n = 3), ascending colon (n = 3), rectum (n = 3), and spleen (n = 3)]. After baseline perfusion recordings, using high-frequency, low-dose bolus injections with weight-adjusted (0.008 mg/kg) ICG, organ-supplying arteries were manually and completely occluded leading to hypoperfusion of the target organ. Continuous organ perfusion monitoring was performed throughout the experimental conditions. RESULTS: After manual occlusion of pre-selected organ-supplying arteries, occlusion of the peripheral arterial supply translated in an immediate decrease in oscillation signal in most organs (3/3 ventricle, 3/3 ascending colon, 3/3 rectum, 2/3 spleen). Occlusion of the central arterial supply resulted in a further decrease or complete disappearance of the oscillation curves in the ventricle (3/3), ascending colon (3/3), rectum (3/3), and spleen (1/3). CONCLUSION: Continuous organ-perfusion monitoring using a high-frequency, low-dose ICG bolus regimen can detect organ hypoperfusion in real-time.

Ultra-wide field indocyanine green angiography in central serous chorioretinopathy.

PURPOSE: To study ultra-widefield indocyanine green angiography (ICGA) patterns in central serous chorioretinopathy (CSC). METHODS: A cross-sectional observational study was undertaken on 30 patients aged 20 to 60 years with CSC at the retina clinic of a tertiary care center. Of them, 43 eyes were affected by CSC, whereas 17 eyes were unaffected as the bilateral disease was observed in 13 patients. All patients were evaluated for best-corrected visual acuity, intraocular pressure, detailed slit-lamp bio-microscopy, indirect ophthalmoscopy, ultra-widefield imaging for pseudo color photograph, fundus autofluorescence (FAF), fundus fluorescein angiography (FFA), and ICGA, and macular swept-source optical coherence tomography (SSOCT) characteristics. RESULTS: The mean age of patients was 41.43 ± 8.81 years (range: 25-59 years). The median log MAR visual acuity in CSC eyes was 0.30 (range: 0.17-1.0), whereas it was 0 in non-CSC fellow eyes ( P < 0.001). Pachy-vessels and late hyperpermeability on ultra-widefield ICGA were observed in all eyes. Vortex vein anastomosis was present in 93% of the affected eyes versus 88.2% in unaffected fellow eyes ( P = 0.61). Disc and posterior poles were the sites of the maximum number of anastomoses in both affected and unaffected eyes ( P = 0.77). Asymmetry in vortex vein drainage of the macula was present in 88.4% of affected eyes and 88.2% of unaffected eyes. CONCLUSION: Studying the ICGA findings in CSC patients emphasized the role of choroidal circulation in pathogenesis as Pachy vessels were observed in all eyes affected with CSC and even fellow eyes of patients. Vortex vein anastomosis around the disc or posterior pole and asymmetric drainage from the macula were noted and could be contributing to CSC pathology.