Development of Single Camera Based Dual-channel Near Infrared Fluorescence Imaging system

Abstract

Near-infrared (NIR) fluorescence imaging system is used in various intraoperative image-guided surgeries as it can provide real-time images of lesions or specific tissues that are difficult to distinguish with the naked eye using an FDA-approved fluorescence contrast agent. To simultaneously acquire color and fluorescence images of two fluorescent agents (indocyanine green and methylene blue), three cameras and additional optical parts are generally used. As a result, the volume of the image acquisition unit increases, which causes inconvenience to the operation and increases production costs. To improve this aspect, we developed an imaging system to acquire a visible image and two NIR fluorescence images in real time using a single camera equipped with two image sensors. The NIR fluorescence images were time-divided into two channels by synchronizing the camera and two excitation lasers, and the noise caused by the crosstalk effect between the two fluorescent agents was removed through image processing. To evaluate the performance of the system, experiments were conducted for the two fluorescent agents to measure the sensitivity, crosstalk effect, and signal-to-background ratio. The compact image acquisition unit reduces the inconvenience caused by movement obstruction in clinical surgery and animal surgery. In addition, the simplicity of the manufacturing method and the reduction of manufacturing costs are expected to facilitate the dissemination of these systems.