Modified Posterior Approach in Thoracoscopic Lateral and Posterior Basal (S9 + 10) Segmentectomy for A9 + 10 and B9 + 10.

BackgroundReports detailing microscopic observations of indocyanine green (ICG) fluorescence imaging (IFI) in hepatocellular carcinoma (HCC) and metastatic liver cancer are rare. We were able to perform macro- and microscopic IFI results in postoperative paraffin-embedded tissue samples and formalin-fixed specimens from liver tumors.MethodsBetween April 2010 and March 2014, 19 patients with HCC or liver metastases of colorectal tumors underwent liver resection. ICG solution was injected into the peripheral vein from 14 to 2 days prior to operation. We observed liver tumor IFI during the laparotomy and IFI in resected liver sections using a photo dynamic emission (PDE) camera. The IFI of paraffin-embedded tissue samples was observed using a charge-coupled device (CCD) camera. Moreover, we microscopically performed tissue section IFI using a fluorescence microscope with an ICG-B-NQF.ResultsWe performed that IFI characteristics depended on tumor type macroscopically and microscopically. In normal liver tissue, fluorescence consistent with the bile canaliculus was observed. HCC had heterogeneous IFI, forming a total or partial tumor and rim pattern. In metastatic carcinoma, we performed that non-tumor cells in the marginal region showed fluorescence and tumor cells in the central region did not fluoresce.ConclusionsWe confirmed that the variations of ICG fluorescence imaging patterns reflect different tumor characteristics in not only macroscopic imaging as previous reports but also microscopic imaging. Moreover, the ICG fluorescence method is useful for postoperative pathological detection of microscopic lesions in histopathological specimens. ICG fluorescence in paraffin-embedded tissue samples and formalin-fixed specimens is preserved in the long term.

BackgroundPulmonary segmentectomy is an important surgical option for complete resection in patients with poor lung function. However, correctly recognizing the intersegmental plane for accurate segmentectomy is sometimes difficult. We therefore developed a novel method that allows the detection of intersegmental planes using an indocyanine green (ICG) fluorescence imaging device, photodynamic eye (PDE) camera, PDE-neo.MethodsAs a prospective study, we performed bronchial ICG-guided segmentectomy using PDE-neo. The patients were placed in a lateral position under general anesthesia, and we performed a combined muscle-sparing minithoracotomy with video assistance. The pulmonary artery, pulmonary vein, and segmental bronchi were separated, and ICG mixed with autologous blood was introduced by spraying through the resected segment bronchi to enable visualization of the intersegmental surface with PDE-neo. This study protocol was approved by the Research Ethics Board of Hamamatsu University School of Medicine, Japan. Written informed consent was obtained from all patients.ResultsOverall, 10 lung malignancy patients, including 8 males and 2 females, participated in this study from March 2011 to October 2013. The median age was 69 years (range, 29–76 years). Pathologic diagnoses were 7 adenocarcinomas, 1 adenosquamous carcinoma, 1 carcinoid tumor, and 1 lung metastasis from the parotid gland cancer. The intersegmental planes of 8 cases could be identified by this method using a PDE-neo, whereas those of 2 cases did not show clear demarcations. The reason was that because of severe emphysema, air flowed from the resected segment to the surrounding segments, obliterating the demarcation between the two segmental planes. There were no recurrent cases and only two deaths due to other diseases were observed; and the 5-year cause-specific survival rate was 100%.ConclusionsIntersegmental planes could be more easily identified using ICG fluorescence imaging during segmentectomy. This method is feasible and effective and has a good long-term prognosis.

Simple SummaryWhile indocyanine green (ICG) fluorescence imaging has widely been used as an intraoperative navigation tool, its efficacy for visualization of hepatic tumors remains to be clarified, especially in robot-assisted hepatectomy (RAH). In our present study, fluorescence imaging identified tumors on hepatic surfaces before hepatic transection in 26/31 tumors. In eight tumors, fluorescence signals were detected from hepatic raw surfaces during parenchymal dissection, enabling surgeons to adjust transection planes to determine surgical margins. As a result, pathological examinations found negative surgical margins at the site of dissected hepatic parenchyma in all tumors identified using fluorescence imaging. On the contrary, a positive surgical margin surrounding dissected hepatic parenchyma was observed in one of two patients in whom ICG was contraindicated. ICG fluorescence imaging enables the identification of hepatic tumors easily even in the setting of RAH, which may be useful for determining surgical margins.The efficacy of indocyanine green (ICG) fluorescence imaging for visualizing hepatic tumors in robot-assisted hepatectomy (RAH) should be validated. This study included 30 consecutive patients with 33 collective tumors who underwent RAH. ICG was administered at a dose of 0.5 mg/kg before surgery. ICG fluorescence imaging was performed intraoperatively. In total, 28 patients with a combined total of 31 tumors underwent ICG fluorescence imaging. Further, 26 (84%) tumors were identified on hepatic surfaces prior to hepatic transection. The fluorescence signals of eight tumors were detected on hepatic raw surfaces during parenchymal dissection, thereby enabling surgeons to adjust the transection planes to ensure appropriate surgical margins. One patient with intrahepatic cholangiocarcinoma tested positive for cancer cells at the dissected stump of the bile duct. However, in all patients in whom ICG fluorescence imaging was used, negative surgical margins were achieved at the site of the dissected hepatic parenchyma. On the other hand, one of two patients with ICG contraindications had a positive surgical margin surrounding the dissected hepatic parenchyma. The median operative time and volume of blood loss were 259 (range: 124–594) min and 150 (range: 1–1150) mL, respectively. ICG fluorescence imaging facilitates the easy identification of hepatic tumors, even in RAH. Hence, it can be useful for confirming appropriate surgical margins.

Reports detailing microscopic observations of indocyanine green (ICG) fluorescence imaging (IFI) in hepatocellular carcinoma (HCC) and metastatic liver cancer are rare. We were able to perform microscopic IFI results in postoperative paraffin-embedded tissue samples from liver tumors. Methods: Between April 2010 and March 2014, 19 patients with HCC or liver metastases of colorectal tumors underwent liver resection. ICG solution was injected into the peripheral vein from 14 to 2 days prior to operation. After operation, we microscopically performed tissue section IFI using a fluorescence microscope with a near-infrared cube. Results: We observed that IFI characteristics depended on tumor type microscopically. In normal liver tissue, fluorescence consistent with a capillary bile cavity was observed. HCC generally had heterogeneous IFI. Well- or moderately differentiated HCC showed cytoplasmic fluorescence as observed by ICG fluorescence microscopy. Furthermore, poorly and unknown differentiated HCC except one case showed nuclear fluorescence in cancer cells and cytoplasmic fluorescence in the surrounding noncancer cells. In metastatic carcinoma, we observed that non-tumor cells in the marginal region and tumor cells in the central region did not fluoresce. Conclusions: We suggest that the variations in ICG fluorescence imaging patterns may reflect different tumor characteristics. ICG fluorescence in paraffin-embedded tissue samples is preserved in the long term.

Laparoscopic ultrasound

BackgroundThe intraoperative identification of intersegmental planes remains a technical challenge in pulmonary segmentectomy. Although indocyanine green (ICG) fluorescence imaging provides reliable visualization, its clinical adoption is limited by transient effects and high costs. This observational study aimed to evaluate the concordance between Doppler ultrasound and ICG fluorescence in the demarcation of intersegmental planes.MethodsIn this retrospective cohort study, we analyzed 12 consecutive patients undergoing video-assisted thoracoscopic segmentectomy at The Fourth Affiliated Hospital of Soochow University (May 2020 to January 2021). Intraoperative Doppler ultrasound was applied to detect intersegmental planes via the assessment of the arterial blood flow differences, with subsequent ICG fluorescence imaging serving as the reference standard. All procedures were performed by senior thoracic surgeons with >10 years of experience in video-assisted thoracic surgery (VATS) segmentectomy. Doppler ultrasound was performed using preset vascular mode with optimized parameters (gain 15–20%, frequency 5.1 MHz, depth 0–1 cm). Inter- and intra-observer variability were not assessed, which represents a methodological limitation.ResultsThe cohort comprised 12 patients (8 males and 4 females; mean age 60.42±13.27 years). A close concordance was observed between the Doppler-identified intersegmental planes and the ICG fluorescence delineation across the majority of cases (11 out of 12, corresponding to a 91.7% concordance rate). Moreover, no procedural complications associated with either modality were noted.ConclusionsDoppler ultrasound demonstrated the potential to a potentially cost-saving and dye-free alternative to ICG fluorescence for intersegmental plane identification. However, these preliminary findings should be validated in larger prospective cohorts to address limitations of single-center design, small sample size, and operator-dependent ultrasound technique.

The use of indocyanine green (ICG) fluorescence imaging (IFI) for fluorescence-guided surgery has been expanding. In this study, we focus on the application of IFI in surgery for colorectal cancers. Recently, gastrointestinal cancers including colorectal cancers have been identified as new targets for sentinel node navigation surgery (SNNS). We examine the feasibility of sentinel lymph node (SLN) mapping guided by IFI in colorectal cancer. In colorectal surgery for early colorectal cancer, discerning tumor location is often difficult. Hence, endoscopic colorectal tattooing (ECT) with India ink is frequently performed. However, ECT with India ink has some complications. We showed the efficacy of a new tattooing method using IFI instead of India ink for effective tumor visualization without adverse effects. The number of harvested lymph nodes (LN) is very significant for the exact staging of colorectal cancer. We performed an evaluation of an IFI method of harvesting lymph nodes (LNs) from resected specimens. IFI allowed easy, highly sensitive, and real-time imaging-guided SLN mapping in patients with colorectal cancer. LN harvesting from resected specimens using IFI is a useful method with a highly improved number of LNs detected. We also found IFI-labeled LNs even when ICG solution was injected ex vivo and observed them in paraffin-embedded specimens that could provide a precise evaluation of the pathological status of LNs including sentinel LNs after surgery.

Laparoscopic anatomical liver resection using indocyanine green fluorescence imaging

Indocyanine green (ICG) fluorescence imaging has been used in the resection surgery and sentinel lymph node biopsy of many tumors. The aim of the present study is to verify the feasibility and effectiveness of ICG fluorescence imaging used for guiding the biopsy and resection of skin squamous cell carcinoma (SSCC). Sixty patients were enrolled, including 18 patients of suspected SSCC and 42 patients of diagnosed SSCC on admission. The ICG fluorescence imaging-guided skin biopsy was performed preoperatively in the 18 cases of suspected SSCC. Fifty-three patients underwent ICG fluorescence imaging-guided radical excision. The results showed that 138 skin tissue samples in 60 patients with preoperative or intraoperative ICG fluorescence imaging-guide biopsy were collected. For a total number of 138 biopsies, 122 specimens were squamous cell carcinoma, and the accuracy rate was 88.4%, which was significantly higher than that of the group without preoperative ICG fluorescence imaging (41/62, 66.1%, P < 0.05). Fifty-three patients underwent surgery guided with ICG fluorescence imaging. Residual fluorescent signals in 24 patients were intraoperatively found and the excision was then expanded until the signals disappeared. Follow-up to November 2022, 12 patients died, of which 5 cases died from the tumor recurrence, and the others died due to advanced ages or other reasons. The recurrence rate was 9.4%, which was not significantly different from that of the group received routine radical resection (4/35, 11.4%, P > 0.05). Moreover, sentinel lymph nodes were successfully detected under ICG fluorescence imaging in the 4 patients with suspected lymph node metastases, and the location of lymph nodes can be precisely identified. ICG fluorescence imaging technique can guide the pathology biopsy to improve the accuracy of pathological examination, and help to identify the boundaries of tumor tissues and sentinel lymph nodes to resect tumor radically during operation.

BackgroundSentinel lymph nodes and lymph node metastases in patients with colorectal cancer (CRC) seriously affect prognosis. In order to improve the accuracy of lymph node assessment during surgery, it is crucial to explore advanced imaging techniques. This study aimed to evaluate the diagnostic value of endoscopic ultrasound (EUS) versus indocyanine green (ICG) fluorescence imaging for sentinel lymph node metastasis (SLNM) and lymph node metastasis (LNM) in patients with CRC.MethodsA total of 120 patients with CRC admitted to our hospital from March 2022 to December 2023 were included in this retrospective study and, according to the detection method, they were divided into ICG group (ICG fluorescence imaging group, n=50) and control group (EUS group, n=70). The general data of patients, sensitivity, specificity, and accuracy of ICG imaging for the diagnosis of SLNM and LNM in patients with CRC were statistically compared between the two groups using gold standard postoperative pathology reports. Area under receiver operating characteristic (ROC) curve was used to analyze the diagnostic value of ICG fluorescence imaging for SLNM and LNM in patients with CRC.ResultsFor diagnosing SLNM in CRC patients, ICG fluorescence imaging achieved sensitivities, specificities, and accuracies of 94.44%, 93.75%, and 94.00%, respectively, significantly outperforming EUS, which achieved sensitivities, specificities, and accuracies of 40.74%, 69.77%, and 58.58% respectively. For LNM diagnosis, ICG fluorescence imaging showed sensitivities, specificities, and accuracies of 80.00%, 92.5%, and 90.00%, compared to 28.57%, 71.43%, and 62.86% for EUS. The area under curve (AUC) of ICG for LNM in patients with CRC was 0.932 with an optimal cut-off value of 0.77, achieving sensitivities and specificities of 95.45% and 81.82%.ConclusionsIn the assessment of SLNM and LNM in patients with CRC, ICG fluorescence imaging is proven to be more valuable than EUS.

Laparoscopic cholecystectomy for a gallbladder with a short cystic duct draining to the accessory right anterior hepatic duct using indocyanine green fluorescence imaging: A case report

Neuroendocrine tumors (NETs) are a group of heterogenous tumors originating from neuroendocrine system. Approximately, 40 percent will go through liver metastases, and liver-directed therapy was proved to improve the survival outcome. Parenchyma-sparing hepatectomy is advocated for the resection of NETs liver metastases while the possible relatively low negative margin rate is concerned. Indocyanine green (ICG) fluorescence imaging provides a real-time navigation on determination of surgical margins in colorectal cancer liver metastases. However, there was no previous study that reported the applications of ICG fluorescence imaging in NETs liver metastases. The present study aimed to evaluate the feasibility and security of using ICG fluorescence imaging to determine surgical margins of NETs liver metastases during operation. A retrospective two-arm cohort study was performed on 25 consecutive patients with NETs liver metastases who underwent laparoscopic parenchyma-sparing hepatectomy (LPSH). Patients were divided into two groups according to whether or not the ICG fluorescence imaging was used. Data on sociodemographic characteristics, laboratory parameters, pathology results, and surgical outcomes were collected. A total of 145 tumors pathologically diagnosed with NETs liver metastases were resected from 25 patients. The pathological results indicated negative margins in all tumors (102/102) in LPSH with ICG fluorescence imaging group. The negative margin rate was significantly higher in LPSH using the ICG fluorescence imaging (100% v.s 88.4%, p = 0.002). Surgical outcomes, including operation time, estimated blood loss, intraoperative transfusion rate, and postoperative morbidity, were comparable between LPSH with and without ICG fluorescence imaging groups. ICG fluorescence imaging showed the potential to identify tumor boundaries and determine surgical margins. This technique may serve as a valuable intraoperative navigation in patients with NETs liver metastases.

The applications of indocyanine green (ICG) fluorescence imaging (IFI) for fluorescent-guided surgery have been expanding. Here we assessed the use of IFI in gastrointestinal tract surgeries. We first evaluated the feasibility of sentinel lymph node (SLN) mapping guided by IFI in gastrointestinal cancers. Twenty-two gastric cancer patients and 26 colorectal cancer patients who had undergone standard surgical resection were enrolled. The SLN detection rate in our preliminary study was 90.9 % and the mean number of SLNs was 3.6 in the gastric cancer patients, and the corresponding values in the colorectal cancer patients were 88.5 % and 2.6. Among the gastric cancer patients, the accuracy was 88.9 % and the false-negative rate was 33.3 %. Secondly, we assessed the efficacy of a new method for tattooing the tumor location using IFI instead of India ink. We succeeded in the ICG marking of early-stage stomach cancer and colon cancer, and our results may lead to the establishment of a new marking procedure instead of the conventional India ink and clipping methods. Lastly, we evaluated whether an IFI method of harvesting lymph nodes (LNs) from resected specimens could improve the accuracy of LN staging. ICG fluorescence-labeled LNs were found even though the ICG solution was injected ex vivo. The IFI method thus improved the LN harvest from resected specimens. This method will provide precise evaluations of the pathological status of LNs.

Since the introduction of indocyanine green angiography more than 25 years ago, few studies have presented interpretative guidelines for indocyanine green fluorescent imaging. We aimed to provide interpretative guidelines for indocyanine green fluorescent imaging through quantitative analysis and to suggest possible indications for indocyanine green fluorescent imaging during robot-assisted sphincter-saving operations. This is a retrospective observational study. This study was conducted at a single center. A cohort of 657 patients with rectal cancer who consecutively underwent curative robot-assisted sphincter-saving operations was enrolled between 2010 and 2016, including 310 patients with indocyanine green imaging (indocyanine green fluorescent imaging+ group) and 347 patients without indocyanine green imaging (indocyanine green fluorescent imaging- group). We tried to quantitatively define the indocyanine green fluorescent imaging findings based on perfusion (mesocolic and colic) time and perfusion intensity (5 grades) to provide probable indications. The anastomotic leakage rate was significantly lower in the indocyanine green fluorescent imaging+ group than in the indocyanine green fluorescent imaging- group (0.6% vs 5.2%) (OR, 0.123; 95% CI, 0.028-0.544; p = 0.006). Anastomotic stricture was closely correlated with anastomotic leakage (p = 0.002) and a short descending mesocolon (p = 0.003). Delayed perfusion (>60 s) and low perfusion intensity (1-2) were more frequently detected in patients with anastomotic stricture and marginal artery defects than in those without these factors (p ≤ 0.001). In addition, perfusion times greater than the mean were more frequently observed in patients aged >58 years, whereas low perfusion intensity was seen more in patients with short descending mesocolon and high ASA classes (≥3). The 300 patients in the indocyanine green fluorescent imaging- group underwent operations 3 years before indocyanine green fluorescent imaging. Quantitative analysis of indocyanine green fluorescent imaging may help prevent anastomotic complications during robot-assisted sphincter-saving operations, and may be of particular value in high-class ASA patients, older patients, and patients with a short descending mesocolon.

Determining tumor location during laparoscopic hepatectomy is challenging due to the lack of direct liver palpation and limitations of intraoperative ultrasound. Advances in indocyanine green (ICG) fluorescence imaging have significantly enhanced real-time visualization during hepatectomy, aiding in tumor detection and guiding resection margins. The present study assessed the clinical relevance of the detection by real-time ICG imaging of a fluorescent rim on the cut surface of the liver in determining resection margins in patients undergoing laparoscopic hepatectomy for malignant liver tumors. The present study evaluated patients who underwent laparoscopic hepatectomy using ICG fluorescence imaging from April 2020 to April 2023. If a fluorescent rim was detected on the cut surface of the liver during parenchymal transection, adjustments were made to the resection plane to ensure proper tumor clearance. The surgical transection plane was guided by real-time ICG fluorescence imaging, ensuring precise resection margins. Of the 300 patients who underwent laparoscopic hepatectomy using ICG fluorescence imaging, 20 were positive for an ICG fluorescent rim on the cut surface of the liver during parenchymal transection. The median tumor size was 26mm (range: 4-52mm), and the median resection margin was 4.5mm (range: 0.8-10mm). The median postoperative hospital stay was 6days (range: 5-21days). This study confirmed the preliminary safety of ICG fluorescence imaging in guiding resection margins during laparoscopic liver resection and provides technical insights into parenchymal preservation.