A major goal for optical imaging techniques is to provide quantitative information in real-time during minimally invasive treatments, where the experience and expertise of the practitioner still play a central role for the successful outcome of the procedure. In this context, Single Snapshot imaging of Optical Properties (SSOP) is an imaging technology based on sinusoidal structured light that has already been demonstrated to have real-time capabilities for wide-field imaging of biological tissues. In this work, we present an endoscopic implementation of SSOP that provides high quality imaging capabilities over a large field of view (70 mm x 70 mm). The instrument is based on a rigid two channels endoscope that can be further adapted for robotized manipulation with systems such as “Da Vinci”. From the optical design point of view, the structured illumination through the first channel of the endoscope is achieved with a laser source coupled to a custom optical path where high definition 2D sinusoidal patterns printed on a glass substrate are used for the generation of high spatial frequency images. The acquisition of the SSOP frames is performed through the second endoscope channel with a tri-sensor CMOS camera covering an RGB channel (for the anatomical view of the surgical field), and two NIR channels selected for optimal oxygenation wavelength coverage (i.e. 665 nm and 860 nm). Real-time imaging is still achievable despite the presence of a deep-learning-based processing architecture and the adoption of a 3D profile correction algorithm, thanks to a custom low-level GPGPU implementation for the visualization and processing which allows us to optimize the total computational time to enable high frame rate acquisitions (>10 fps). The imaging performances of a handheld version of the system will soon be assessed through pre-clinical trials on swine models before moving to the surgical robot version.
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