Intraoperative Near-infrared Imaging Research Articles

The use of near-infrared imaging with indocyanine green in the ovarian tissue transplantation: a case report.

The request for fertility preservation has consistently increased in recent years. To our knowledge this case report is the first to describe the application of near-infrared intraoperative imaging using indocyanine green (NIR-ICG) during ovarian tissue transplantation (OTT), to assist surgeon choosing the site of implantation of ovarian fragments. OTT was performed in a 42-year-old woman using NIR-ICG to evaluate the vascularisation of peritoneal area as the site of implantation for the ovarian graft. we believe this new approach could be useful in identifying the best reimplantation site.

Novel intraoperative near-infrared imaging strategy to identify abnormalities in the anterior mediastinum

Thoracic surgeons are frequently asked to biopsy suspicious tissues in the anterior mediastinum to discriminate between a reactive versus malignant pathology such as lymph nodes. The most common benign cause of a mediastinal lymph node is a reactive lymph node from a prior infection or inflammatory process such as post-COVID or granulomatous disease. The most common malignant cause is a lymphoproliferative disorder but also metastatic disease from neck, breast and other regional cancers. Biopsies in this location are challenging because they are far from the trachea and the sternum is a barrier to most diagnostic procedures. Thus, a surgical biopsy is frequently required and a common procedure for Thoracic surgeons. Technically, identifying these lesions can be challenging, particularly for small lesions or those in patients with high body mass index. In order to improve contrast between diseased tissue in the anterior mediastinum and surrounding adipose tissue, we have been studying near-infrared imaging during surgery using indocyanine green (ICG) to give contrast to the abnormal tissues and to avoid an unnecessary extended resection. We developed a modified technique to give ICG to a patient during a biopsy in the anterior mediastinum to specifically highlight abnormal tissues. As a proof-of-principle, we present a case of a young woman with a suspicious 2cm mediastinal lymph node that required surgical biopsy.

Intraoperative Tumor Detection Using Pafolacianine.

Cancer is a leading cause of death worldwide, with increasing numbers of new cases each year. For the vast majority of cancer patients, surgery is the most effective procedure for the complete removal of the malignant tissue. However, relapse due to the incomplete resection of the tumor occurs very often, as the surgeon must rely primarily on visual and tactile feedback. Intraoperative near-infrared imaging with pafolacianine is a newly developed technology designed for cancer detection during surgery, which has been proven to show excellent results in terms of safety and efficacy. Therefore, pafolacianine was approved by the U.S. Food and Drug Administration (FDA) on 29 November 2021, as an additional approach that can be used to identify malignant lesions and to ensure the total resection of the tumors in ovarian cancer patients. Currently, various studies have demonstrated the positive effects of pafolacianine's use in a wide variety of other malignancies, with promising results expected in further research. This review focuses on the applications of the FDA-approved pafolacianine for the accurate intraoperative detection of malignant tissues. The cancer-targeting fluorescent ligands can shift the paradigm of surgical oncology by enabling the visualization of cancer lesions that are difficult to detect by inspection or palpation. The enhanced detection and removal of hard-to-detect cancer tissues during surgery will lead to remarkable outcomes for cancer patients and society, specifically by decreasing the cancer relapse rate, increasing the life expectancy and quality of life, and decreasing future rates of hospitalization, interventions, and costs.

Real-time intraoperative near-infrared autofluorescence imaging to locate the parathyroid glands: A preliminary report.

Identification and localization of parathyroid glands (PGs) remains a challenge for surgeons. The aim of this study was to evaluate the efficiency of intraoperative near-infrared autofluorescence (NIRAF) imaging to detect PGs in thyroid and parathyroid diseases. Seventy-six patients undergoing surgery for thyroid or parathyroid diseases between July 9, 2020 and August 20, 2021 were retrospectively analyzed. Intraoperative carbon nanoparticle (CN) negative imaging and handheld NIRAF imaging were successively performed for each patient. Of 206 PGs that needed to be identified for surgery, 162 were identified by NIRAF imaging, with a theoretical rate of identification of 78.64%. This was higher than the rate of identification with CN negative imaging, which was 75.73%. The number of PGs identified by NIRAF imaging and CN negative imaging did not differ significantly in either total thyroidectomy or thyroid lobectomy. In addition, the autofluorescence (AF) intensity of secondary parathyroid adenoma was weaker than that of normal PGs. NIRAF imaging is potentially a more efficient tool for identification of PGs than CN negative imaging, with a shorter learning curve and lower risk. It may not be well-suited to secondary hyperthyroidism or adenoma, but it was more efficient at identifying excised specimens than visual identification by a surgeon.

The LIver SEntinel LYmph-node (LISELY) study: A prospective intraoperative real time evaluation of liver lymphatic drainage and sentinel lymph-node using near-infrared (NIR) imaging with Indocyanine Green (ICG)

Near-infrared (NIR) imaging with Indocyanine green (ICG) has been recently proposed for the sentinel lymph node (SLN) and lymphatic out-flow detection in several tumors. Nowadays its application in primary and secondary liver (LCs) and biliary cancers (BTCs) remains uninvestigated.A proof-of-concept prospective observational study including 18 patients underwent surgery for LCs and BTCs from September 2021 to November 2021 was carried out. The intraoperative NIR imaging with ICG was detected at predefined temporary intervals in order to identify the main lymphatic out-flow and the SLN. In 14 patients (77.8%) the lymphatic outflow pathway was visualized with a median time of 3 min after ICG injection (IQR 3–10). The SLN was detected and confirmed at the histological examination in 12 patients (66.7%). Intraoperative NIR imaging with ICG is a safe and feasible method to identify the lymphatic out-flow and SLN in LCs and BTCs.

190: ENDOSCOPIC SUBMUCOSAL DISSECTION (ESD) AND ROBOTIC SENTINEL NODE NAVIGATION SURGERY FOR EARLY GASTRIC CANCER: FIRST EXPERIENCE AND PRELIMINARY RESULTS

Abstract Background and aim Early gastric cancer (EGC) is defined as a cancer limited to mucosa (T1a) and submucosa (T1b). The 5-year survival rates are respectively 96% and 83% for T1a and T1b. Despite endoscopic submucosal dissection (ESD) is considered the standard treatment for EGC, literature reports a quite considerable rate of lymph-node metastasis (2% to 18%). Combined surgical-endoscopic treatment can achieve accurate resection of EGC, solving the problem of lymphadenectomy which cannot be performed endoscopically. Near infrared (NIR) fluorescence imaging with indocyanine green (ICG) was recently introduced for lymphatic mapping in several tumors. The aim of the study is to evaluate the feasibility and safety of ESD in combination with robotic ICG guided sentinel node navigation surgery (SNNS). Methods ICG was endoscopically injected intraoperatively into the submucosal layer around the tumor. Intraoperative NIR imaging with ICG was carried out with a near-infrared camera system built into the robotic platform. The first lymph node which had taken up ICG appeared as a green spot and was identified as the sentinel node (SN). SN was then sent for extemporaneous histopathological examination. When ICG fluorescence extended to the second nodal stations a ICG guided robotic basin lymphadenectomy was performed. Basin lymph nodes were sent for definitive histopathological analysis. If no tumoral cells were identified in the SN, an ESD with standard technique was conducted. If the SN pathological examination revealed tumoral cells, a robotic radical resection and D2 lymphadenectomy was completed. Results Seven ESDs with SNNS and basin lymphadenectomy basin were performed. No gastric perforations or other intraoperative complications were registered. Mean operative time was 148.6 minutes. All the procedures histologically resulted in complete excisions. No lymph nodes metastasis was demonstrated in either the SN or the basin lymph nodes. A mean of 12 lymph-nodes was collected. Mean hospitalization time was 2.8 days. Conclusion In our preliminary experience, combined ESD and SNNS could be recommended as a safe and effective treatment for EGC in patients with potential risk of LN metastasis or in patients with multiple comorbidity in order to avoid more invasive organ resections.

Intraoperative near-infrared molecular imaging for diagnostic thoracoscopy in difficult clinical scenario.

Precise diagnosis in intrathoracic malignancies is paramount for adequate treatment planning. Standard approach is histologic analysis from targeted biopsy obtained with different invasive procedures. Rarely, in difficult clinical scenarios, even gold standard diagnostic procedures can be ineffective in obtaining a satisfying result. Procedural developments and technological improvements applied to the chosen technique can be helpful to deal with such situation. We present two clinical cases of suspected intrathoracic malignancy in which repeated unsuccessful diagnostic procedures had already been attempted. We adopted a protocol based on intraoperative fluorescence during diagnostic thoracoscopy to increase diagnostic efficacy. In both cases we obtained a precise pathological diagnosis.

Fast and Durable Intraoperative Near-infrared Imaging of Ovarian Cancer Using Ultrabright Squaraine Fluorophores.

The residual tumor after surgery is the most significant prognostic factor of patients with epithelial ovarian cancer. Near-infrared (NIR) fluorescence-guided surgery is actively utilized for tumor localization and complete resection during surgery. However, currently available contrast-enhancing agents display low on-target binding, unfavorable pharmacokinetics, and toxicity, thus not ideal for clinical use. Here we report ultrabright and stable squaraine fluorophores with optimal pharmacokinetics by introducing an asymmetric molecular conformation and surface charges for rapid transporter-mediated cellular uptake. Among the tested, OCTL14 shows low serum binding and rapid distribution into cancer tissue via organic cation transporters (OCTs). Additionally, the charged squaraine fluorophores are retained in lysosomes, providing durable intraoperative imaging in a preclinical murine model of ovarian cancer up to 24 h post-injection. OCTL14 represents a significant departure from the current bioconjugation approach of using a non-targeted fluorophore and would provide surgeons with an indispensable tool to achieve optimal resection.

Intraoperative near-infrared autofluorescence imaging for hypocalcemia risk reduction after total thyroidectomy: Evidence from a meta-analysis.

This meta-analysis evaluates whether near-infrared autofluorescence (NIRAF) imaging reduces the risk of hypocalcemia after total thyroidectomy. A systematic literature search in PubMed, EMBASE, Web of Science, and Cochrane Library for studies from June 2011 to January 2021 comparing total thyroidectomy with NIRAF and conventional surgery (naked eye). Six eligible studies involving 2180 patients were included. The prevalence of transient hypocalcemia was 8.11% (40/493) and 25.19% (425/1687) in the NIRAF and naked eye groups (p < 0.0001), respectively. The prevalence of permanent hypocalcemia was 0% (0/493) and 2.19% (37/1687) in the NIRAF and naked eye groups (p=0.05), respectively. NIRAF reduces the risk of transient hypocalcemia and may possibly lower the rate of permanent hypocalcemia. Nonetheless, further studies are needed to verify our results and evaluate the cost-effectiveness of NIRAF in real-world clinical practice.

Candidate Biomarkers for Specific Intraoperative Near-Infrared Imaging of Soft Tissue Sarcomas: A Systematic Review.

Simple SummaryNear-infrared imaging of tumors during surgery facilitates the oncologic surgeon to distinguish malignant from healthy tissue. The technique is based on fluorescent tracers binding to tumor biomarkers on malignant cells. Currently, there are no clinically available fluorescent tracers that specifically target soft tissue sarcomas. This review searched the literature to find candidate biomarkers for soft tissue sarcomas, based on clinically used therapeutic antibodies. The search revealed 7 biomarkers: TEM1, VEGFR-1, EGFR, VEGFR-2, IGF-1R, PDGFRα, and CD40. These biomarkers are abundantly present on soft tissue sarcoma tumor cells and are already being targeted with humanized monoclonal antibodies. The conjugation of these antibodies with a fluorescent dye will yield in specific tracers for image-guided surgery of soft tissue sarcomas to improve the success rates of tumor resections.Surgery is the mainstay of treatment for localized soft tissue sarcomas (STS). The curative treatment highly depends on complete tumor resection, as positive margins are associated with local recurrence (LR) and prognosis. However, determining the tumor margin during surgery is challenging. Real-time tumor-specific imaging can facilitate complete resection by visualizing tumor tissue during surgery. Unfortunately, STS specific tracers are presently not clinically available. In this review, STS-associated cell surface-expressed biomarkers, which are currently already clinically targeted with monoclonal antibodies for therapeutic purposes, are evaluated for their use in near-infrared fluorescence (NIRF) imaging of STS. Clinically targeted biomarkers in STS were extracted from clinical trial registers and a PubMed search was performed. Data on biomarker characteristics, sample size, percentage of biomarker-positive STS samples, pattern of biomarker expression, biomarker internalization features, and previous applications of the biomarker in imaging were extracted. The biomarkers were ranked utilizing a previously described scoring system. Eleven cell surface-expressed biomarkers were identified from which 7 were selected as potential biomarkers for NIRF imaging: TEM1, VEGFR-1, EGFR, VEGFR-2, IGF-1R, PDGFRα, and CD40. Promising biomarkers in common and aggressive STS subtypes are TEM1 for myxofibrosarcoma, TEM1, and PDGFRα for undifferentiated soft tissue sarcoma and EGFR for synovial sarcoma.

Near-infrared intraoperative imaging with indocyanine green is beneficial in video-assisted thoracoscopic segmentectomy for patients with chronic lung diseases: a retrospective single-center propensity-score matched analysis

ObjectiveTo investigate whether video-assisted thoracoscopic segmentectomy using near-infrared fluorescence imaging had better intersegmental plane visualization and peri-operative outcome in patients with chronic lung diseases.MethodsData were collected retrospectively from March 2014 and August 2019. A total of 92 patients with pulmonary nodules underwent near-infrared fluorescence guided uni-port thoracoscopic segmentectomy(NIF-VATS), 149 patients underwent thoracoscopic segmentectomy with inflation-deflation method(ID-VATS). After 1:1 propensity matching, perioperative outcomes between NIF-VATS and ID-VATS was compared.ResultsIncision size was 3 cm in both group.Mean operative time was 79 min in NIF-VATS group and 96 min in ID-VATS group. The intersegmental plane was not clear in 33 cases of ID-VATS group, and no clear boundary was found after prolonged waiting time. Emphysema or pulmonary bullae could be found in chest CT scan in these patients, they all were diagnosed as chronic obstructive pulmonary disease. In NIF-VATS group, the intersegmental plane was not clear in 8 cases. Under the guidance of three-dimensional reconstruction and preoperative positioning, the oncological margin length of both groups met the requirements of surgical quality control. The intraoperative blood loss, number of lymph node resection, showed no statistical difference between the two groups. Postoperative air leakage was more often observed in ID-VATS group. The postoperative drainage duration, postoperative hospitalization time was shorter in ID-VATS group.ConclusionsCompared with inflation-deflation method, segmentectomy using NIF imaging is feasible for patients with chronic lung diseases with better intersegmental plane, shorter operation time, less complications, it might lead to faster recovery.

Intraoperative near-infrared imaging can identify canine mammary tumors, a spontaneously occurring, large animal model of human breast cancer.

IntroductionCurrent methods of intraoperative margin assessment in breast conserving surgery are impractical, unreliable, or time consuming. We hypothesized that intraoperative near-infrared (NIR) imaging with an FDA-approved NIR optical contrast agent could identify canine mammary tumors, a spontaneous large animal model of human breast cancer, during surgery.MethodsDogs with mammary tumors underwent a standard of care lumpectomy or mastectomy with wide surgical margins 20 hours after indocyanine green administration (3 mg/kg IV). During surgery, NIR imaging was performed on tumors and wound margins in situ and tumors and lymph nodes ex vivo. Following resection, the wound bed was examined for residual fluorescence. Fluorescence intensity was determined by signal-to-background ratio (SBR). All tumors, areas of residual fluorescence, and lymph nodes underwent histopathologic analysis.ResultsThere were 41 mammary tumors in 16 female dogs. Twenty tumors were malignant and 21 were benign. Twenty-eight tumors were fluorescent (mean SBR 1.5±0.2). Sensitivity of fluorescence for all malignant tumors was 80% (16/20) and 93.3% (14/15) for malignant tumors > 2 cm. Specificity for malignancy was low (< 2cm = 55%; > 2cm = 30%). Tumors > 2 cm were more likely to be fluorescent (OR 6.05, 95% CI 1.50–24.44, P = 0.011) but not more likely to be malignant (OR 3.09, 95% CI 0.86–11.14, P = 0.085) than tumors ≤ 2 cm. Four out of seven inguinal lymph nodes excised in the mastectomy specimen fluoresced. All four drained malignant tumors; however only 2/4 contained metastatic disease.ConclusionSystemic ICG accumulates reliably in malignant canine mammary tumors > 2 cm. Although no tumor margins fluoresced, a wider margin of normal tissue is removed in canine mastectomy, making direct comparisons with breast conserving surgery difficult. Targeted NIR imaging agents are likely required to improve detection of smaller tumors and improve the specificity of NIR imaging for residual disease and metastatic lymph node detection.

A classification system and treatment algorithm for mastectomy flap ischemia in alloplastic breast reconstruction

Mastectomy flap necrosis remains a major cause of failed breast reconstruction with an associated significant financial/psychological burden. Language describing ischemic mastectomy flaps is imprecise as ischemia can result from many causes and can manifest in different ways. Similarly, management of mastectomy flap ischemia varies depending on its etiology. Intraoperative near-infrared imaging (NIR) with indocyanine green (ICG) is an established modality for evaluation of mastectomy flap perfusion. Herein, we define the types of flap ischemia demonstrated via NIR imaging and propose an algorithm for its management. A retrospective review was performed of patients who underwent mastectomy and NIR imaging of mastectomy flaps from 2014 to 2017. Patient characteristics, operative details, and outcomes were recorded. Following retrospective review, distinct patterns of ischemia were identified, and a classification system and treatment algorithm were developed. Type A; diffuse hypoperfusion can be caused by a number of factors (hypotension, vasoconstrictive agents, etc.). It is best treated with delayed reconstruction. Type B; geographic hypoperfusion may be caused by electro-cautery burn, inaccurate dissection, or retractor injury. It can be treated by resection/primary closure or delayed reconstruction. Type C; marginal/incisional hypoperfusion is best treated with debridement. Type D; diffuse marginal perfusion is seen with overfilled tissue-expanders or an oversized implant within a smaller skin envelope. Management includes deflation/downsizing. An algorithm was developed for treatment of the four ischemia types. NIR imaging aides in delineating the type of ischemic injury. Classification of mastectomy flap ischemia allows precise communication between providers and provides a framework for decision-making.

The safety and feasibility of intraoperative near-infrared fluorescence imaging with indocyanine green in thoracoscopic sympathectomy for primary palmar hyperhidrosis.

BackgroundWe investigated the safety and feasibility of intraoperative near‐infrared (NIR) imaging using indocyanine green (ICG) during sympathectomy in the management of primary palmar hyperhidrosis (PPH).MethodsWe performed a retrospective review of 142 patients (ICG group) who underwent endoscopic thoracic sympathectomy (ETS) between February 2018 and April 2019. All patients received a 5 mg/kg infusion of ICG 24 hours preoperatively. The vital signs before and after ICG injection and adverse reactions were recorded. Meanwhile, 498 patients (Non‐ICG group) who underwent ETS by normal thoracoscopy during August 2017 to April 2019 were also reviewed to compare the abnormal white blood cell (WBC) counts, alanine transaminase (ALT), aspartate transaminase (AST), blood urea nitrogen (BUN), and creatinine (Cr) levels before and after operation between two groups.ResultsFor ICG group, the vital signs including body temperature, heart rate and blood pressure before and after ICG injection were stable. There was no significant difference in the abnormal WBC counts, ALT, AST, BUN, and Cr levels before and after operation between two groups. Only one patient had mild adverse reaction (0.7%) after ICG injection. The visibility rate of all sympathetic ganglions was 96.7% (1369/1415). The visibility rate from T1 to T5 was 98.23% (278/283), 98.23% (278/283), 97.17% (275/283), 95.76% (271/283), and 94.35% (267/283), respectively. There was no significant difference in the visibility rate with regard to age, gender, height, weight, body mass index, and PPH grade.ConclusionsNIR fluorescence imaging with ICG for identifying sympathetic ganglions is relatively safe and feasible.Key points• Significant findings of the study. NIR fluorescence imaging with ICG for identifying sympathetic ganglions is relatively safe and feasible.• What this study adds.This technology may take the place of the rib‐oriented method as standard practice for the precise localization of sympathetic ganglions, and may improve the effect of sympathectomies.

Re:Intraoperative Near-Infrared Imaging Can Identify Neoplasms and Aid in Real-time Margin Assessment During Pancreatic Resection

Re:Intraoperative Near-Infrared Imaging Can Identify Neoplasms and Aid in Real-time Margin Assessment During Pancreatic Resection

A prospective single-center protocol for using near-infrared fluorescence imaging with indocyanine green during staging laparoscopy to detect small metastasis from pancreatic cancer

BackgroundPancreatic resection and radiotherapy are powerful tools in the multidisciplinary local treatment of pancreatic ductal adenocarcinoma (PDAC). However, 10–20% of patients with preoperatively resectable PDAC have radiographically occult metastases, which results in laparotomy without resection. This study aims to explore the utility of intraoperative near-infrared (NIR) imaging with indocyanine green (ICG) during staging laparoscopy to detect PDAC metastasis.MethodsThis prospective study will evaluate patients with radiographically non-metastatic PDAC before they undergo planned pancreatic resection or chemoradiotherapy. Enrolled patients will receive ICG intravenously (0.5 mg/kg) before the staging laparoscopy. During the staging laparoscopy, the abdominal cavity will be observed using standard white-light laparoscopic imaging and then using NIR-ICG imaging. Suspicious lesions that are detected using standard imaging and/or NIR-ICG imaging will be examined intraoperatively using frozen sections and permanent specimens. We will evaluate the benefit of NIR-ICG imaging based on its ability to identify additional liver or peritoneal lesions that were not detected during standard white-light imaging.DiscussionThis study will help establish the clinical utility of NIR-ICG imaging to more precisely identify metastases from radiographically non-metastatic PDAC. This approach may help avoid needless major surgery or radiotherapy.Trial registrationThis protocol was registered on April 1, 2017 on the UMIN Clinical Trials Registry: UMIN000025900 and February 26, 2019 on the Japan Registry of Clinical Trials: jRCT1051180076.

Intraoperative Near-Infrared Fluorescence Imaging With Second-Window Indocyanine-Green Offers Accurate and Real-Time Correction for Brain Shift and Anatomic Inconsistencies in Framless Neuronavigation

Abstract INTRODUCTION Neuronavigation allows neurosurgeons to localize intracranial structures in 3D space and has been shown to have positive impacts on patient survival in neuro-oncology surgery. However, its major limitation is the intraoperative brain-shift phenomenon, in which the brain moves during surgery due to physical, surgical, and/or biological factors, invalidating the preoperative registration and leading to inaccuracies in the cranium. One reliable way to account for brain-shift intraoperatively may be to use tumor-targeting near-infrared fluorophores, such as ICG accumulating in neoplastic tissue (ie, Second-Window ICG), which offers real-time visualization of tumors through normal cortex and dura. METHODS Patients undergoing craniotomy for primary resection of intracranial tumors were enrolled under an ongoing clinical trial investigating the efficacy of SWIG. For this analysis, retrospective data were collected on patients in whom neuronavigation was used to plan the craniotomy in such a way as to place the tumor in the center of the craniotomy (ie, parasagittal tumors, skull-base tumors, and large/asymmetrical tumors were excluded). During surgery, near-infrared imaging was performed before and after durotomy to localize the gross tumor. Image analysis was performed to measure the deviation between the craniotomy center and the center of the tumor as seen with near-infrared fluorescence. RESULTS A total of 63 patients (24 high-grade-gliomas, 12 meningiomas, 25 metastases, 2 others) were included in this preliminary analysis. Neuronavigation demonstrated a median deviation of 22.4% (range 7.7%-44.4%) relative to craniotomy size. Patient position was a significant predictor of neuronavigation inaccuracy, with the prone position having significantly higher inaccuracy (28.5 ± 8.8%) compared to the supine (19.3 ± 9.2%, P-value = .015) or the lateral (17.9 ± 6.6%, P-value = .012) positions. Additionally, the neuronavigation device used and postgraduate training level of the residents performing the registration trended towards significance on multivariate analysis. In contrast, near-infrared fluorescence perfectly delineated the tumor in all cases. CONCLUSION We demonstrate that near-infrared fluorescence imaging offers more accurate localization of intracranial tumors compared to frameless neuronavigation. Near-infrared imaging could potentially be used to adjust neuronavigation registrations intraoperatively to enhance accuracy. Further prospective studies with distance measurements could better explore this potential benefit of intraoperative near-infrared imaging.

RE: "Intraoperative Near-infrared Imaging Can Identify Neoplasms and Aid in Real-time Margin Assessment During Pancreatic Resection".

Bouvet, Michael MD∗,†; Lwin, Thinzar M. MD∗,†; Hoffman, Robert M. PhD∗,†,‡ Author Information

Near-Infrared Intraoperative Imaging of Pelvic Autonomic Nerves: Clinical Trial

Near-Infrared Intraoperative Imaging of Pelvic Autonomic Nerves: Clinical Trial

Near-infrared intraoperative imaging for minimally invasive pulmonary metastasectomy for sarcomas

BackgroundComplete pulmonary metastasectomy for sarcoma metastases provides patients an opportunity for long-term survival and possible cure. Intraoperative localization of preoperatively identified metastases and identification of occult lesions can be challenging. In this trial, we evaluated the efficacy of near-infrared (NIR) intraoperative imaging using second window indocyanine green during metastasectomy to identify known metastases and to detect occult nodules. MethodsThirty patients with pulmonary nodules suspicious for sarcoma metastases were enrolled in an open-label, feasibility study (NCT02280954). All patients received intravenous indocyanine green (5 mg/kg) 24 hours before metastasectomy. Patients 1 through 10 (cohort 1) underwent metastasectomy via thoracotomy to assess fluorescence patterns of nodules detected by traditional methods (preoperative imaging and intraoperative visualization/bimanual palpation). After confirming reliability within cohort 1, patients 11 through 30 (cohort 2) underwent video-assisted thoracic surgery metastasectomy with NIR imaging. ResultsIn cohort 1, 14 out of 16 preoperatively identified pulmonary metastases (87.5%) displayed tumor fluorescence. Nonfluorescent metastases were deeper than fluorescent metastases (2.1 cm vs 1.3 cm; P = .03). Five out of 5 metastases identified during thoracotomy displayed fluorescence. NIR imaging identified 3 additional occult lesions in this cohort. In cohort 2, 33 out of 37 known pulmonary metastases (89.1%) displayed fluorescence. Nonfluorescent tumors were deeper than 2.0 cm (P = .007). NIR imaging identified 24 additional occult lesions. Of 24 occult lesions, 21 (87.5%) were confirmed metastases and the remaining 3 nodules were lymphoid aggregates. ConclusionsNIR intraoperative imaging with indocyanine green (5 mg/kg and 24 hours before surgery) localizes known sarcoma pulmonary metastases and identifies otherwise occult lesions. This approach may be a useful intraoperative adjunct to improve metastasectomy.