Intraoperative micro-hepatocellular carcinoma detection using surgical navigation system with fluorescence molecular imaging technology
Chongwei Chi, Institute of Automation, Chinese Academy of Sciences
Introduction: For liver cancer surgery, how to find the micro-hepatocellular carcinoma (MHCC) is a challenge to surgeons. Radiology approaches such as X-rays, computed tomography (CT), ultrasound (US), magnetic resonance imaging (MRI) and positron emission tomography (PET) have been considered for diagnosis and postoperative evaluations. However, these medical imaging methods were not applicable for intraoperative MHCC surgery. In order to assist the surgeons to precisely locate MHCC during surgery, we developed a novel surgical navigation system for real-time fluorescence molecular imaging. To prove its feasibility, the experiments on patients for detecting the MHCC in liver cancer with indocyanin green (ICG) were executed.
Methods: We used a CCD camera (MVC1500MF-M00, Microview, China) to collect near-infrared (NIR) fluorescence images. The fluorescence filter (wavelength 810nm-870nm) was fixed in front of CCD camera and C-mount lens (12.5mm, f/1.4, Pentax) was chosen. We used laser (MW-GX-785, Feimiao Technology Co., Ltd. China) to provide NIR light source. About 72 hours prior to surgery, according to liver monitoring usage of 0.5mg/kg, indocyanine green (ICG, Yichuang Pharmaceutical Co., Ltd., China), which was diluted to 5mg/ml, were intravenously injected and during surgery real-time fluorescent video images were acquired.
Results: 30 patients were included in this study. 2-5mm MHCCs were only diagnosed by our system in 4 of all patients. Furthermore, the surgeons can dissect liver tumor margins according to the guidance of our system. Compared to the current methods, one patient was diagnosed positive tumor margin by our system after the enlarge dissection and confirmed by intraoperative pathology verification. No allergic reactions were reported after the injection of ICG.
Conclusions: This study demonstrates our system can achieve the precision detection of MHCC during surgery.