Indocyanine Green Fluorescence Onsite Visualization and Assessment System for Optical Guided Surgery
The Indocyanine Green (ICG) Fluorescence Onsite Visualization and Assessment System (iFOVAS) for optical guided surgery project has been funded by the Ministry of Science and Technology's Germination Program for supporting the development of medical devices with high market potential. The iFOVAS is a state-of-the-art imaging system developed by a multidisciplinary team from National Taiwan University Hospital (NTUH), Instrument Technology Research Center (ITRC) of National Applied Research Laboratories (NARLabs), the Department of Computer Science and Information Engineering of National Taiwan University (NTU-CSIE), and Wan Fang Hospital.
Traditional approaches for optical guided surgery include administration of ICG to patients for visualizing blood vessels. However, the need for a bucket detector and high cost of imaging systems used in ICG imaging limits its usability and availability for surgeons. The iFOVAS provides a novel visualization tool for surgeons through direct onsite projection of tomography measurements derived from ICG fluorescence patterns, which greatly improves their consistency and intuitiveness during surgery.
ICG, a near-infrared (NIR) fluorescence dye, is injected into a patient's body for visualizing blood vessels and lymph nodes. After absorbing NIR light (wavelength, 760−780 nm), ICG emits fluorescence at 800−850−nm wavelengths. Because ICG fluorescence is invisible to the human eye, a special IR camera that detects the fluorescence penetrating through human tissue and capture images is required. ICG is an FDA-approved drug and is widely used for surgery and liver function assessment. The dye is mainly used to trace blood vessels and lymph flow in order to determine tumor distribution, imaging grafted veins after coronary artery bypass surgery, locating breast cancer lymph node metastasis, and monitoring blood flow after organ transplantation.
The most critical challenge encountered by surgeons when using the current ICG fluorescence imaging technology is that they must repeatedly view images on a screen to locate the fluorescent area, which interferes with their concentration during surgery.
The iFOVAS was developed by using light emitting diodes as the light sources. It can convert invisible NIR light to visible light and project tomography measurements of the fluorescence image, thus aiding surgeons in focusing on surgery.
Moreover, the surgeon training process mainly relies on the use of their eyes; the iFOVAS can provide surgeons a more intuitive user experience and improve the surgical process with immediacy, accuracy, and safety, thus increasing surgery success rates.
In addition, the onsite visualization and real-time projection of fluorescence images on a surgical site during surgery is extremely useful for junior surgeons; they would benefit from intuitive visual surgery and improve their surgical skills with a faster learning curve. Therefore, through the use of this system, patients can receive higher quality medical services and senior surgeons can have more effective teaching support and share their valuable experiences with junior counterparts. In the future, the iFOVAS, which has high market potential, will be used in practical applications in surgery.
The iFOVAS research team has received the 12th National Innovation Award from the Institute for Biotechnology and Medicine Industry.