An imaging analysis and reconstruction method for multiple-micro-electro-mechanical system mirrors-based off-centre scanning optical coherence tomography probe

An endoscopic optical coherence tomography (OCT) probe that can perform full circumferential scans using a circular array of six micro-electro-mechanical system (MEMS) mirrors has been developed. Inside the OCT probe, each of the six MEMS mirrors forms an independent scanning unit; circumferential OCT images are acquired by off-centre scanning and combining the image data from the individual multiple scanning units. Here, an imaging analysis and reconstruction (IAR) method is proposed to construct endoscopic OCT volumetric images from the multiple individual MEMS scanning unit. Imaging procedures of six-MEMS mirrors-based, eight-MEMS mirrors-based and twelve-MEMS mirrors-based OCT probes have been analyzed theoretically. All the data sets are in the Cartesian coordinate system and need to be transformed as fan-shaped images located in the polar coordinate system. The 3-D volume rendering is employed for visualizing the endoscopic data. Typically, this method is used into the image reconstruction of a six-MEMS mirrors-based endoscopic probe. The imaging area is also appropriate for scanning large-scale biological tissue through qualitative and quantitative evaluation. The proposed IAR method using the multiple-MEMS mirrors-based endoscopic off-centre scanning OCT probe has been verified in an experiment of imaging a swine small intestines. This method can be used to analyze the imaging of the multi-MEMS mirrors-based endoscopic OCT probe, which can image the large-scale gastrointestinal tracts in the future.