Dissecting the surgeon's personality: cross-cultural comparisons in Western Europe.

AIM: The surgeon's personality contributes to variation in surgical decision-making. Previous work on surgeon personality has largely been reserved to Anglo-Saxon studies, with limited international comparisons. In this work we built upon recent work on gastrointestinal surgeon personality and aimed to detect international variations. METHOD: Gastrointestinal surgeons from the UK and the Netherlands were invited to participate in validated personality assessments (44-item, 60-item Big Five Inventory; BFI). These encompass personality using five domains (open-mindedness, conscientiousness, extraversion, agreeableness and negative emotionality) with three subtraits each. Mean differences in domain factors were calculated between surgeon and nonsurgeon populations from normative data using independent-samples t-tests, adjusted for multiple testing. The items from the 44-item and 60-item BFI were compared between UK and Dutch surgeons and classified accordingly: identical (n = 16), analogous (n = 3), comparable (n = 12). RESULTS: UK (n = 78, 61.5% male) and Dutch (n = 280, 65% male) gastrointestinal surgeons had marked differences in the domains of open-mindedness, extraversion and agreeableness compared with national normative datasets. Moreover, although surgeons had similar levels of emotional stability, country of work influenced differences in specific BFI items. For example, Netherlands-based surgeons scored highly on questions related to sociability and organization versus UK-based surgeons who scored highly on creative imagination (p < 0.0001). CONCLUSION: In a first cross-cultural setting, we identified country-specific personality differences in gastrointestinal surgeon cohorts across domain and facet levels. Given the variation between Dutch and UK surgeons, understanding country-specific data could be useful in guiding personality research in healthcare. Furthermore, we advocate that future work adopts consensus usage of the five factor model.

Quantitative perfusion assessment using indocyanine green during surgery - current applications and recommendations for future use.

PURPOSE: Incorrect assessment of tissue perfusion carries a significant risk of complications in surgery. The use of near-infrared (NIR) fluorescence imaging with Indocyanine Green (ICG) presents a possible solution. However, only through quantification of the fluorescence signal can an objective and reproducible evaluation of tissue perfusion be obtained. This narrative review aims to provide an overview of the available quantification methods for perfusion assessment using ICG NIR fluorescence imaging and to present an overview of current clinically utilized software implementations. METHODS: PubMed was searched for clinical studies on the quantification of ICG NIR fluorescence imaging to assess tissue perfusion. Data on the utilized camera systems and performed methods of quantification were collected. RESULTS: Eleven software programs for quantifying tissue perfusion using ICG NIR fluorescence imaging were identified. Five of the 11 programs have been described in three or more clinical studies, including Flow® 800, ROIs Software, IC Calc, SPY-Q™, and the Quest Research Framework®. In addition, applying normalization to fluorescence intensity analysis was described for two software programs. CONCLUSION: Several systems or software solutions provide a quantification of ICG fluorescence; however, intraoperative applications are scarce and quantification methods vary abundantly. In the widespread search for reliable quantification of perfusion with ICG NIR fluorescence imaging, standardization of quantification methods and data acquisition is essential.

Intraoperative fluorescence delineation of head and neck cancer with a fluorescent anti-epidermal growth factor receptor nanobody.

Intraoperative near-infrared (NIR) fluorescence imaging is a technology with high potential to provide the surgeon with real-time visualization of tumors during surgery. Our study explores the feasibility for clinical translation of an epidermal growth factor receptor (EGFR)-targeting nanobody for intraoperative imaging and resection of orthotopic tongue tumors and cervical lymph node metastases. The anti-EGFR nanobody 7D12 and the negative control nanobody R2 were conjugated to the NIR fluorophore IRDye800CW (7D12-800CW and R2-800CW). Orthotopic tongue tumors were induced in nude mice using the OSC-19-luc2-cGFP cell line. Tumor-bearing mice were injected with 25 µg 7D12-800CW, R2-800CW or 11 µg 800CW. Subsequently, other mice were injected with 50 or 75 µg of 7D12-800CW. The FLARE imaging system and the IVIS spectrum were used to identify, delineate and resect the primary tumor and cervical lymph node metastases. All tumors could be clearly identified using 7D12-800CW. A significantly higher tumor-to-background ratio (TBR) was observed in mice injected with 7D12-800CW compared to mice injected with R2-800CW and 800CW. The highest average TBR (2.00 ± 0.34 and 2.72 ± 0.17 for FLARE and IVIS spectrum, respectively) was observed 24 hr after administration of the EGFR-specific nanobody. After injection of 75 µg 7D12-800CW cervical lymph node metastases could be clearly detected. Orthotopic tongue tumors and cervical lymph node metastases in a mouse model were clearly identified intraoperatively using a recently developed fluorescent EGFR-targeting nanobody. Translation of this approach to the clinic would potentially improve the rate of radical surgical resections.

Optimization of sentinel lymph node mapping in bladder cancer using near-infrared fluorescence imaging.

BACKGROUND AND OBJECTIVES: Unlike other cancers, the Sentinel Lymph Node (SLN) procedure in bladder cancer requires special attention to the injection technique. The aim of this study was to assess feasibility and to optimize tracer injection technique for SLN mapping in bladder cancer patients using NIR fluorescence imaging. METHODS: Twenty patients with invasive bladder cancer scheduled for radical cystectomy were prospectively enrolled. Indocyanine green (ICG) bound to human serum albumin (complex ICG:HSA; 500 µM) was injected peritumourally to permit SLN mapping. ICG:HSA was first administrated serosally (n = 5), and subsequently mucosally by cystoscopic injection (n = 15). In the last cohort of 12 patients treated with cystoscopic injection, the bladder was kept filled with saline for at least 15 min. RESULTS: Fluorescent lymph nodes were observed only in the patient group with cystoscopic injection of ICG:HSA. Filling of the bladder post-injection was of added value to promote drainage of ICG:HSA to the lymph nodes, and in 11 of these 12 patients (92%) one or more NIR fluorescent lymph nodes were identified. CONCLUSIONS: The current study demonstrates proof-of-principle of using NIR fluorescence imaging for SLN identification in bladder cancer. Cystoscopic injection with distension of the bladder appears optimal for SLN mapping.

Consensus conference statement on fluorescence-guided surgery (FGS) ESSO course on fluorescence-guided surgery.

BACKGROUND: Fluorescence-guided surgery (FGS) has emerged as an innovative technique with promising applications in various surgical specialties. However, clinical implementation is hampered by limited availability of evidence-based reference work supporting the translation towards standard-of-care use in surgical practice. Therefore, we developed a consensus statement on current applications of FGS. METHODS: During an international FGS course, participants anonymously voted on 36 statements. Consensus was defined as agreement ≥70% with participation grade of ≥80%. All participants of the questionnaire were stratified for user and handling experience within five domains of applicability (lymphatics & lymph node imaging; tissue perfusion; biliary anatomy and urinary tracts; tumor imaging in colorectal, HPB, and endocrine surgery, and quantification and (tumor-) targeted imaging). Results were pooled to determine consensus for each statement within the respective sections based on the degree of agreement. RESULTS: In total 43/52 (81%) course participants were eligible as voting members for consensus, comprising the expert panel (n = 12) and trained users (n = 31). Consensus was achieved in 17 out of 36 (45%) statements with highest level of agreement for application of FGS in tissue perfusion and biliary/urinary tract visualization (71% and 67%, respectively) and lowest within the tumor imaging section (0%). CONCLUSIONS: FGS is currently established for tissue perfusion and vital structure imaging. Lymphatics & lymph node imaging in breast cancer and melanoma are evolving, and tumor tissue imaging holds promise in early-phase trials. Quantification and (tumor-)targeted imaging are advancing toward clinical validation. Additional research is needed for tumor imaging due to a lack of consensus.

Clinical trial of combined radio- and fluorescence-guided sentinel lymph node biopsy in breast cancer.

BACKGROUND: Combining radioactive colloids and a near-infrared (NIR) fluorophore permits preoperative planning and intraoperative localization of deeply located sentinel lymph nodes (SLNs) with direct optical guidance by a single lymphatic tracer. The aim of this clinical trial was to evaluate and optimize a hybrid NIR fluorescence and radioactive tracer for SLN detection in patients with breast cancer. METHODS: Patients with breast cancer undergoing SLN biopsy were enrolled. The day before surgery, a periareolar injection of indocyanine green (ICG)-99mTc-radiolabelled nanocolloid was administered and a lymphoscintigram acquired. Blue dye was injected immediately before surgery. Intraoperative SLN localization was performed using a γ probe and the Mini-FLARE™ NIR fluorescence imaging system. Patients were divided into two dose groups, with one group receiving twice the particle density of ICG and nanocolloid, but the same dose of radioactive 99mTc. RESULTS: Thirty-two patients were enrolled in the trial. At least one SLN was identified before and during operation. All 48 axillary SLNs could be detected by γ tracing and NIR fluorescence imaging, but only 42 of them stained blue. NIR fluorescence imaging permitted detection of lymphatic vessels draining to the SLN up to 29 h after injection. Doubling the particle density did not yield a difference in fluorescence intensity (median 255 (range 98-542) versus 284 (90-921) arbitrary units; P = 0.590) or signal-to-background ratio (median 5·4 (range 3·0-15·4) versus 4·9 (3·5-16·3); P = 1·000) of the SLN. CONCLUSION: The hybrid NIR fluorescence and radioactive tracer permitted accurate preoperative and intraoperative detection of the SLNs in patients with breast cancer. REGISTRATION NUMBER: NTR3685 (Netherlands Trial Register; http://www.trialregister.nl).

Dose optimization for near-infrared fluorescence sentinel lymph node mapping in patients with melanoma.

BACKGROUND: Regional lymph node involvement is the most important prognostic factor in cutaneous melanoma. As only 20% of patients with melanoma have occult nodal disease and would benefit from a regional lymphadenectomy, the sentinel lymph node (SLN) biopsy was introduced. Near-infrared (NIR) fluorescence has been hypothesized to improve SLN mapping. OBJECTIVES: To assess the potential of intraoperative NIR fluorescence imaging to improve SLN mapping in patients with melanoma and to examine the optimal dose of indocyanine green adsorbed to human serum albumin (ICG:HSA). METHODS: Fifteen consecutive patients with cutaneous melanoma underwent the standard SLN procedure using (99m) technetium-nancolloid and patent blue. In addition, intraoperative NIR fluorescence imaging was performed after injection of 1·6 mL of 600, 800, 1000 or 1200 µmolL(-1) of ICG: HSA in four quadrants around the primary excision scar. RESULTS: NIR fluorescence SLN mapping was successful in 93% of patients. In one patient, no SLN could be identified using either conventional methods or NIR fluorescence. A total of 30 SLNs (average 2·0, range 1-7) were detected, 30 radioactive (100%), 27 blue (73%) and 30 NIR fluorescent (100%). With regard to the effect of concentration on signal-to-background ratios a trend (P=0·066) was found favouring the 600, 800 and 1000 µmol L(-1) groups over the 1200 µmol L(-1) group. CONCLUSION: This study demonstrates feasibility and accuracy of SLN mapping using ICG: HSA. Considering safety, cost and pharmacological characteristics, an ICG: HSA concentration of 600 µmolL(-1) appears optimal for SLN mapping in cutaneous melanoma, although lower doses need to be assessed.

Near-infrared fluorescence sentinel lymph node biopsy in vulvar cancer: a randomised comparison of lymphatic tracers.

This study aims to confirm the feasibility of near-infrared (NIR) fluorescence imaging for sentinel lymph node (SLN) biopsy in vulvar cancer and to compare the tracer indocyanine green (ICG) bound to human serum albumin (HSA) versus ICG alone. Women received 99mTc-nanocolloid and patent blue for SLN detection. Subsequently, women randomly received ICG:HSA or ICG alone. In 24 women, 35 SLNs were intraoperatively detected. All SLNs detected were radioactive and NIR fluorescent and 27 (77%) were blue. No significant difference was found between ICG:HSA and ICG alone. This trial confirms the feasibility of NIR fluorescence imaging for SLN mapping in vulvar cancer.

Near-infrared fluorescence angiography with indocyanine green for perfusion assessment of DIEP and msTRAM flaps: A Dutch multicenter randomized controlled trial.

Background: A common complication after a DIEP flap reconstruction is the occurrence of fat necrosis due to inadequate flap perfusion zones. Intraoperative identification of ischemic zones in the DIEP flap could be optimized using indocyanine green near-infrared fluorescence angiography (ICG-NIR-FA). This randomized controlled trial aims to determine whether intraoperative ICG-NIR-FA for the assessment of DIEP flap perfusion decreases the occurrence of fat necrosis. Design/methods: This article describes the protocol of a Dutch multicenter randomized controlled clinical trial: the FAFI-trial. Females who are electively scheduled for autologous breast reconstruction using DIEP or muscle-sparing transverse rectus abdominis muscle (msTRAM) flaps are included. A total of 280 patients will be included in a 1:1 ratio between both study arms. In the intervention arm, the intraoperative assessment of flap perfusion will be based on both regular clinical parameters and ICG-NIR-FA. The control arm consists of flap perfusion evaluation only through the regular clinical parameters, while ICG-NIR-FA images are obtained during surgery for which the surgeon is blinded. The main study endpoint is the difference in percentage of clinically relevant fat necrosis between both study arms, evaluated two weeks and three months after reconstruction. Conclusion: The FAFI-trial, a Dutch multicenter randomized controlled clinical trial, aims to investigate the clinical added value of intraoperative use of standardized ICG-NIR-FA for assessment of DIEP/msTRAM flap perfusion in the reduction of fat necrosis. Clinical trial registration number: NCT05507710; NL 68623.058.18.

Quantification of near-infrared fluorescence imaging with indocyanine green in free flap breast reconstruction.

BACKGROUND: One of the complications of free flap breast reconstruction is the occurrence of skin and fat necrosis. Intra-operative use of near-infrared (NIR) fluorescence imaging with Indocyanine Green (ICG) has the potential to predict these complications. In this study, the quantification of the fluorescence intensity measured in free flap breast reconstruction was performed to gain insight into the perfusion patterns observed with ICG NIR fluorescence imaging. METHODS: ICG NIR fluorescence imaging was performed in patients undergoing free flap breast reconstruction following mastectomy. After completion of the arterial and venous anastomosis, 7.5 mg ICG was administered intravenously. The fluorescence intensity over time was recorded using the Quest Spectrum Platform®. Four regions of interest (ROI) were selected based on location and interpretation of the NIR fluorescence signal: (1) The perforator, (2) normal perfusion, (3) questionable perfusion, and (4) low perfusion. Time-intensity curves were analyzed, and two parameters were extracted: Tmax and Tmax slopes. RESULTS: Successful ICG NIR fluorescence imaging was performed in 13 patients undergoing 17 free flap procedures. Region selection included 16 perforators, 17 normal perfusions, 8 questionable perfusions, and 5 low perfusion ROIs. Time-intensity curves of the perforator ROIs were comparable to the ROIs of normal perfusion and demonstrated a fast inflow. No outflow was observed for the ROIs with questionable and low perfusion. CONCLUSION: This study provides insight into the perfusion patterns observed with ICG NIR fluorescence imaging in free flap breast reconstruction. Future studies should correlate quantitative parameters with clinical perfusion assessment and outcome.

Near-infrared fluorescence imaging in patients undergoing pancreaticoduodenectomy.

BACKGROUND: Intraoperative visualization of pancreatic tumors has the potential to improve radical resection rates. Intraoperative visualization of the common bile duct and bile duct anastomoses could be of added value. In this study, we explored the use of indocyanine green (ICG) for these applications and attempted to optimize injection timing and dose. METHODS: Eight patients undergoing a pancreaticoduodenectomy were injected intravenously with 5 or 10 mg ICG. During and after injection, the pancreas, tumor, common bile duct and surrounding organs were imaged in real time using the Mini-FLARE™ near-infrared (NIR) imaging system. RESULTS: No clear tumor-to-pancreas contrast was observed, except for incidental contrast in 1 patient. The common bile duct was clearly visualized using NIR fluorescence, within 10 min after injection, with a maximal contrast between 30 and 90 min after injection. Patency of biliary anastomoses could be visualized due to biliary excretion of ICG. CONCLUSION: No useful tumor demarcation could be visualized in pancreatic cancer patients after intravenous injection of ICG. However, the common bile duct and biliary anastomoses were clearly visualized during the observation period. Therefore, these imaging strategies could be beneficial during biliary surgery in cases where the surgical anatomy is aberrant or difficult to identify.

Traumatic rupture of a Meckel's diverticulum due to blunt abdominal trauma in a soccer game: A case report.

INTRODUCTION: a Meckel's diverticulum is one of the most common congenital anomalies of the digestive tract. The reported lifetime complication rate is 4%, mostly due to hemorrhage, obstruction, perforation or inflammation. A symptomatic Meckel's diverticulum due to rupture after blunt abdominal trauma is very rare. We believe this case report is the first reporting a rupture of a Meckel's diverticulum after a low velocity blunt abdominal trauma and outlining the importance of a thorough and complete examination of the patient after blunt abdominal trauma. PRESENTATION OF CASE: a 17-year-old male presented with abdominal pain after blunt abdominal trauma during a soccer game. Physical examination showed signs of peritonitis in all quadrants of the abdomen. During admission the patient deteriorated with decreasing blood pressure and raising pulse rate. A CT-scan showed free abdominal fluid. Our patient was scheduled for an emergent laparotomy where a perforated Meckel's diverticulum with fecal spill was found. A segmental ileal resection was performed. Post-operative, patient developed a pneumonia and also intra-abdominal abscesses treated with percutaneous drainage. After an admission period of 17-days the patient was discharged. CONCLUSION: perforation of a Meckel's diverticulum is rarely suspected as a cause of acute deterioration following blunt abdominal trauma. This case shows the importance of awareness of this kind of injury especially in male patients.

Real-time intraoperative detection of breast cancer using near-infrared fluorescence imaging and Methylene Blue.

BACKGROUND: Despite recent developments in preoperative breast cancer imaging, intraoperative localization of tumor tissue can be challenging, resulting in tumor-positive resection margins during breast conserving surgery. Based on certain physicochemical similarities between Technetium((99m)Tc)-sestamibi (MIBI), an SPECT radiodiagnostic with a sensitivity of 83-90% to detect breast cancer preoperatively, and the near-infrared (NIR) fluorophore Methylene Blue (MB), we hypothesized that MB might detect breast cancer intraoperatively using NIR fluorescence imaging. METHODS: Twenty-four patients with breast cancer, planned for surgical resection, were included. Patients were divided in 2 administration groups, which differed with respect to the timing of MB administration. N = 12 patients per group were administered 1.0 mg/kg MB intravenously either immediately or 3 h before surgery. The mini-FLARE imaging system was used to identify the NIR fluorescent signal during surgery and on post-resected specimens transferred to the pathology department. Results were confirmed by NIR fluorescence microscopy. RESULTS: 20/24 (83%) of breast tumors (carcinoma in N = 21 and ductal carcinoma in situ in N = 3) were identified in the resected specimen using NIR fluorescence imaging. Patients with non-detectable tumors were significantly older. No significant relation to receptor status or tumor grade was seen. Overall tumor-to-background ratio (TBR) was 2.4 ± 0.8. There was no significant difference between TBR and background signal between administration groups. In 2/4 patients with positive resection margins, breast cancer tissue identified in the wound bed during surgery would have changed surgical management. Histology confirmed the concordance of fluorescence signal and tumor tissue. CONCLUSIONS: This feasibility study demonstrated an overall breast cancer identification rate using MB of 83%, with real-time intraoperative guidance having the potential to alter patient management.

Intraoperative near-infrared fluorescence imaging of colorectal metastases targeting integrin α(v)ß(3) expression in a syngeneic rat model.

AIM: Near-infrared (NIR) fluorescence optical imaging is a promising technique to assess the extent of colorectal metastases during curative-intended surgery. However, NIR fluorescence imaging of liver metastases is highly challenging due to hepatic uptake and clearance of many fluorescent dyes. In the current study, the biodistribution and the ability to demarcate liver and peritoneal metastases were assessed during surgery in a syngeneic rat model of colorectal cancer using an integrin α(v)ß(3)-directed NIR fluorescence probe. METHODS: Liver tumors and peritoneal metastases were induced in 7 male WAG/Rij rats by subcapsular inoculation of 0.5 × 10(6) CC531 colorectal cancer rat cells into three distinct liver lobes. Intraoperative and ex vivo fluorescence measurements were performed 24 (N = 3 rats, 7 tumors) and 48 h (N = 4 rats, 9 tumors) after intravenous administration of the integrin α(v)ß(3)-directed NIR fluorescence probe. RESULTS: Colorectal metastases had a minimal two-fold higher NIR fluorescence signal than healthy liver tissue and other abdominal organs (p < 0.001). The tumor-to-background ratio was independent of time of imaging (24 h vs. 48 h post-injection; p = 0.31), which facilitates flexible operation planning in future clinical applications. Total fluorescence intensity was significantly correlated with the size of metastases (R(2) = 0.92 for the 24 h group, R(2) = 0.96 for the 48 h group). CONCLUSION: These results demonstrate that colorectal intra-abdominal metastases can be clearly demarcated during surgery using an integrin α(v)ß(3) targeting NIR fluorescence probe. Translating these findings to the clinic will have an excellent potential to substantially improve the quality of cancer surgery.