Noninvasive structural and microvascular anatomy of oral mucosae using handheld optical coherence tomography.

In this study, we demonstrated the feasibility of using a handheld optical coherence tomography (OCT) for visualizations of the microstructural and microvascular features of various oral mucosal types. To scan arbitrary locations of the oral mucosa, a scanning probe was developed, composed of a probe body fabricated by a 3D printer, miniaturized two-axis galvanometer, relay lenses, and reflective prism. With a 3D printing technique, the probe weight and the system volume were greatly reduced, enabling the effective improvement of imaging artifacts from unconscious motion and system complexity. Additionally, in our design, the distal end of the probe can be switched to fit various oral conditions, and the optical parameters of the probe, such as the transverse resolution, working distance, and probe length can be easily varied. The results showed that the epithelium and lamina propria layers, as well as the fungiform papilla and salivary gland, were differentiated. Moreover, various microcirculation features at different mucosal sites were identified that are potentially effective indicators for the diagnosis of premalignant lesions. The demonstrated results indicate that the developed OCT system is a promising tool for noninvasive imaging of oral mucosae.