Automated FF-OCT imaging for efficient and accurate analysis of 3D cell culture models

Traditional full-field optical coherence tomography (FF-OCT) systems face limitations in imaging efficiency and data redundancy, particularly when applied to complex biological samples. To address these issues, we developed an automated FF-OCT system that uses a variable resolution z-scanning strategy to dynamically adjust the voxel resolution of acquired images according to sample structures. The system was validated using 3D HepaRG cell cultures embedded in micro-hydrogels. To optimize imaging efficiency and minimize data redundancy, an in-air voxel resolution of 0.7×0.7×5µm³ was applied to the region of interest (ROI) for detailed sample analysis, while a lower resolution of 1.4×1.4×10µm³ was used in non-ROI areas. Compared to traditional equidistant acquisition methods, the variable resolution strategy reduced imaging time by over 20% and data storage requirements by more than 35%, with deviations in morphological parameters, including volume and surface area, kept below 1%. Robustness tests across multiple cell culture batches confirmed the system's reliability in accurately capturing complex biological structures. This study demonstrates a significant advancement in FF-OCT technology, providing a practical, high-efficiency, and high-precision solution for non-invasive imaging of complex biological samples.