MEMS-based large-field-of-view optical coherence tomography endoscopy for gastric ulcer imaging in mice

The diagnosis of gastrointestinal diseases requires effective structural and functional information, which also requires that the endoscope has excellent performance in terms of high resolution, a large field of view, and three-dimensional penetration depth. However, existing optical and electronic endoscopes are limited to superficial observation and are unable to capture information from deep tissues. Here, we propose a front-view MEMS-based optical coherence tomography (OCT) endoscopic probe with a diameter of 8 mm, a lateral resolution of 25 µm, an imaging field of view (FOV) of 4 × 4 mm², and a penetration depth of 2 mm. Compared with previously reported MEMS-based OCT endoscopic probes, it allows front-view observation and a larger FOV. We utilized the probe to image the internal organs in mice and study the development and self-healing of the acute gastric ulcer. The findings indicate that during the development of a stomach ulcer, a distinct lesion can be visualized on OCT cross-sectional images, disrupting the integrity of the mucosal layer. During the self-healing of a gastric ulcer, the gastric septal tissue healed to a normal state, with recovery of stomach wall thickness and gradual disappearance of the ulcer area. Our work demonstrates that the MEMS-based OCT probe has potential for minimally invasive or non-invasive imaging and diagnosis of gastrointestinal diseases in the future.