Background
During laparoscopic cholecystectomy, common bile duct (CBD) injury is a rare but severe complication. To reduce the risk of injury, near-infrared (NIR) fluorescent cholangiography using ...indocyanine green (ICG) has recently been introduced as a novel method of visualizing the biliary system during surgery. To date, several studies have shown feasibility of this technique; however, liver background fluorescence remains a major problem during fluorescent cholangiography. The aim of the current study was to optimize ICG dose and timing for NIR cholangiography using a quantitative intraoperative camera system during open hepatopancreatobiliary (HPB) surgery. Subsequently, these results were validated during laparoscopic cholecystectomy using a laparoscopic fluorescence imaging system.
Methods
Twenty-seven patients who underwent NIR imaging using the Mini-FLARE image-guided surgery system during open HPB surgery were analyzed to assess optimal dosage and timing of ICG administration. ICG was intravenously injected preoperatively at doses of 5, 10, and 20 mg, and imaged at either 30 min (early) or 24 h (delayed) post-injection. Next, the optimal doses found for early and delayed imaging were applied to two groups of seven patients (
n
= 14) undergoing laparoscopic NIR fluorescent cholangiography during laparoscopic cholecystectomy.
Results
Median liver-to-background contrast was 23.5 (range 22.1–35.0), 16.8 (range 11.3–25.1), 1.3 (range 0.7–7.8), and 2.5 (range 1.3–3.6) for 5 mg/30 min, 10 mg/30 min, 10 mg/24 h, and 20 mg/24 h, respectively. Fluorescence intensity of the liver was significantly lower in the 10 mg delayed-imaging dose group compared with the early imaging 5 and 10 mg dose groups (
p
= 0.001), which resulted in a significant increase in CBD-to-liver contrast ratio compared with the early administration groups (
p
< 0.002). These findings were qualitatively confirmed during laparoscopic cholecystectomy.
Conclusion
This study shows that a prolonged interval between ICG administration and surgery permits optimal NIR cholangiography with minimal liver background fluorescence.
Objectives Near-infrared fluorescence imaging has the potential to improve sentinel lymph node mapping in vulvar cancer, which was assessed in the current study. Furthermore, dose optimization of ...indocyanine green adsorbed to human serum albumin was performed. Study Design Nine vulvar cancer patients underwent the standard sentinel lymph node procedure using99m technetium-nancolloid and patent blue. In addition, intraoperative imaging was performed after peritumoral injection of 1.6 mL of 500, 750, or 1000 μM of indocyanine green adsorbed to human serum albumin. Results Near-infrared fluorescence sentinel lymph node mapping was successful in all patients. A total of 14 sentinel lymph nodes (average, 1.6; range, 1–4) were detected: 14 radioactive (100%), 11 blue (79%), and 14 near-infrared fluorescent (100%). Conclusion This study demonstrates feasibility and accuracy of sentinel lymph node mapping using indocyanine green adsorbed to human serum albumin. Considering safety, cost, and pharmacy preferences, an indocyanine green adsorbed to human serum albumin concentration of 500 μM appears optimal for sentinel lymph node mapping in vulvar cancer.
Background
Improved imaging methods and surgical techniques have created a new era in hepatopancreatobiliary (HPB) surgery. Despite these developments, visual inspection, palpation, and ...intraoperative ultrasound remain the most utilized tools during surgery today. This is problematic, though, especially in laparoscopic HPB surgery, where palpation is not possible. Optical imaging using near-infrared (NIR) fluorescence can be used for the real-time assessment of both anatomy (e.g., sensitive detection and demarcation of tumours and vital structures) and function (e.g., assessment of luminal flow and tissue perfusion) during both open and minimally invasive surgeries.
Methods
This article reviews the published literature related to preclinical development and clinical applications of NIR fluorescence imaging during HPB surgery.
Results
NIR fluorescence imaging combines the use of otherwise invisible NIR fluorescent contrast agents and specially designed camera systems, which are capable of detecting these contrast agents during surgery. Unlike visible light, NIR fluorescent light can penetrate several millimetres through blood and living tissue, thus providing improved detectability. Applications of this technique during HPB surgery include tumour imaging in liver and pancreas, and real-time imaging of the biliary tree.
Conclusions
NIR fluorescence imaging is a promising new technique that may someday improve surgical accuracy and lower complications.
Purpose Near infrared fluorescence imaging is a promising technique that offers real-time visual information during surgery. In this study we report the first clinical results to our knowledge of ...ureteral imaging using near infrared fluorescence after a simple peripheral infusion of methylene blue. Furthermore, we assessed the optimal timing and dose of methylene blue. Materials and Methods A total of 12 patients who underwent lower abdominal surgery were included in this prospective feasibility study. Near infrared fluorescence imaging was performed using the Mini-FLARE™ imaging system. To determine optimal timing and dose, methylene blue was injected intravenously at doses of 0.25, 0.5 or 1 mg/kg after exposure of the ureters. Imaging was performed for up to 60 minutes after injection. Results In all patients both ureters could be clearly visualized within 10 minutes after infusion of methylene blue. The signal lasted at least up to 60 minutes after injection. The mean signal-to-background ratio of the ureter was 2.27 ± 1.22 (4), 2.61 ± 1.88 (4) and 3.58 ± 3.36 (4) for the 0.25, 0.5 and 1 mg/kg groups, respectively. A mixed model analysis was used to compare signal-to-background ratios among dose groups and times, and to assess the relationship between dose and time. A significant difference among time points (p <0.001) was found. However, no difference was observed among dose groups (p = 0.811). Conclusions This study demonstrates the first successful use of near infrared fluorescence using low dose methylene blue for the identification of the ureters during lower abdominal surgery.
Near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) has recently been introduced to improve the sentinel lymph node (SLN) procedure. Several optical tracers have been successfully ...tested. However, the optimal tracer formulation is still unknown. This study evaluates the performance of ICG-technetium-99m (99mTc)-nanocolloid in relation to 2 most commonly used ICG-based formulas during SLN biopsy in vulvar cancer.
Twelve women who planned to undergo SLN biopsy for stage I vulvar cancer were prospectively included. Sentinel lymph node mapping was performed using the dual-modality radioactive and NIR fluorescence tracer ICG-99mTc-nanocolloid. All patients underwent combined SLN localization using NIR fluorescence and the (current) gold standard using blue dye and radioactive guidance.
In all 12 patients, at least 1 SLN was detected during surgery. A total of 21 lymph nodes (median 2; range, 1-3) were resected. Median time between skin incision and first SLN detection was 8 (range, 1-22) minutes. All resected SLNs were both radioactive and fluorescent, although only 13 (62%) of 21 SLNs stained blue. Median brightness of exposed SLNs, expressed as signal-to-background ratio, was 5.4 (range, 1.8-11.8). Lymph node metastases were found in 3 patients.
Near-infrared fluorescence-guided SLN mapping is feasible and outperforms blue dye staining. Premixing ICG with 99mTc-nanocolloid provides real-time intraoperative imaging of the SN and seems to be the optimal tracer combination in terms of intraoperative detection rate of the SN (100%). Moreover, ICG-99mTc-nanocolloid allows the administration of a 5-times lower injected dose of ICG (compared with ICG and ICG absorbed to human serum albumin) and can be injected up to 20 hours before surgery.
Abstract Objective Near-infrared fluorescence imaging using indocyanine green (ICG) has recently been introduced as a novel technique for sentinel lymph node (SLN) mapping in early-stage cervical ...cancer. Although preclinical research has shown that ICG adsorbed to human serum albumin (ICG:HSA) improves its performance, the need for HSA has not yet been confirmed in cervical cancer patients. The current randomized study aims to determine whether ICG:HSA offers advantages over using ICG alone. Methods Eighteen consecutive early-stage cervical cancer patients scheduled to undergo pelvic lymphadenectomy were included. Prior to surgery, 1.6 mL of 500 μM ICG:HSA or 500 μM ICG alone was injected transvaginally in 4 quadrants around the tumor. The Mini-FLARE imaging system was used for intraoperative NIR fluorescence detection and quantitation. Results SLNs were identified intraoperatively in 78% of the patients. Patient and tumor characteristics were equally distributed over both treatment groups. No significant difference in signal-to-background ratio (9.3 vs. 10.1, P = .72) or average number of detected SLNs (2.9 vs 2.7, P = .84) was found between the ICG:HSA group and the ICG alone group, respectively. Conclusions In conclusion, this double-blind, randomized trial showed no advantage of ICG:HSA over ICG alone for the SLN procedure in early-stage cervical cancer. Further optimization is required to improve the intraoperative detection rate.
Near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) has the potential to improve sentinel lymph node (SLN) mapping of breast cancer. We performed a randomized clinical trial to ...assess the value of blue dyes when used in combination with NIR fluorescence. We also preliminarily examined the possibility of performing SLN mapping without radiotracers.
Clinical trial subjects were 24 consecutive breast cancer patients scheduled to undergo SLN biopsy. All patients received standard of care using 99(m) technetium-nanocolloid and received 1.6 mL of 500 μM ICG injected periareolarly. Patients were randomly assigned to undergo SLN biopsy with or without patent blue. To assess the need for radiocolloids to localize the SLN or SLNs, the surgeon did not use the handheld gamma probe during the first 15 min after the axillary skin incision.
SLN mapping was successful in 23 of the 24 patients. No significant difference was found in signal-to-background ratio between the groups with and without patent blue (8.3 ± 3.8 vs. 10.3 ± 5.7, respectively, P = 0.32). In both groups, 100 % of SLNs were radioactive and fluorescent, and in the patent blue group, only 84 % of SLNs were stained blue. In 25 % of patients, the use of the gamma probe was necessary to localize the SLN within the first 15 min.
This study shows that there is no benefit of using patent blue for SLN mapping in breast cancer patients when using NIR fluorescence and 99(m) technetium-nanocolloid. NIR fluorescence imaging outperformed patent blue in all patients.
Diffuse optical spectroscopy (DOS) has the potential to enable monitoring of tumor response during chemotherapy, particularly in the early stages of treatment. This study aims to assess feasibility ...of DOS for monitoring treatment response in HER2-negative breast cancer patients receiving neoadjuvant chemotherapy (NAC) and compare DOS with tumor response assessment by MRI.
Patients received NAC in six cycles of 3 weeks. In addition to standard treatment monitoring by dynamic contrast enhanced MRI (DCE-MRI), DOS scans were acquired after the first, third, and last cycle of chemotherapy. The primary goal was to assess feasibility of DOS for early assessment of tumor response. The predictive value of DOS and DCE-MRI compared with pathologic response was assessed.
Of the 22 patients, 18 patients had a partial or complete tumor response at pathologic examination, whereas 4 patients were nonresponders. As early as after the first chemotherapy cycle, a significant difference between responders and nonresponders was found using DOS (HbO2 86% ± 25 vs. 136% ± 25, P = 0.023). The differences between responders and nonresponders continued during treatment (halfway treatment, HbO2 68% ± 22 vs. 110% ± 10, P = 0.010). Using DCE-MRI, a difference between responders and nonresponders was found halfway treatment (P = 0.005) using tumor volume measurement calculations.
DOS allows for tumor response assessment and is able to differentiate between responders and nonresponders after the first chemotherapy cycle and halfway treatment. In this study, DOS was equally effective in predicting tumor response halfway treatment compared with DCE-MRI. Therefore, DOS may be used as a novel imaging modality for (early) treatment monitoring of NAC.
PDF
