Robot-Assisted Optical Coherence Tomography for Automatic Wide-Field Scanning

Optical coherence tomography (OCT) is a three-dimensional, non-invasive, high-speed imaging modality capable of providing micro-scale tissue images in real-time. OCT is widely used in clinical practice and is a promising method for optical biopsy. However, the lateral imaging range at the millimeter level makes it unable to cover larger regions of interest, and the limits of focal depth range make the distance between the probe and the tissue demanding. Here, we present a flexible robotic OCT system that enables automatic wide-field imaging on arbitrary tissue surfaces with high resolution. We developed a servo control method based on real-time 3D OCT images to achieve accurate localization of the scan head with six degrees of freedom (DOF). After completing the imaging of multiple pre-planned points, we use the robotic pose and the collected image information for coarse-to-fine registration and stitching to achieve an ultra-wide imaging range. ​We verified the system's performance by scanning experiments on samples and biological tissues. Qualitative and quantitative results demonstrated that the system could achieve accurate positioning, scanning, and image stitching, and has better flexibility and higher degree of automation than existing systems. The proposed robot-assisted OCT imaging system could realize automatic high-resolution and wide-field imaging on complex tissue surfaces. It may be helpful in the fields of lesion boundary identification, precise surgical guidance, and intelligent theranostics.