Endoscopic optical coherence tomography (OCT) has been demonstrated for volumetric imaging of subsurface features with high resolution. However, it is difficult to enable endoscopic OCT angiography (OCTA) due to the low inter-frame stability of endoscopic OCT. Recently, stable distal rotational scanning of micromotor catheter enabled imaging of structural features in the en face plane as well as endoscope OCTA. However, most endoscopic OCT in the lab and almost all commercial ones use proximal scanning catheters for diagnosing endoscopic tissues which should be designed much smaller than micromotor catheters. Here, we presented a proximal scanning endoscopic OCT technology that enabled OCTA. A spatiotemporal singular value decomposition (SVD) process was used to remove the eigen components that represented static tissue signals to generate that of the final moving particles. Primary results revealed that the endoscopic imaging system enabled OCTA in the two-and three-dimensional in vitro flow phantom. As the catheter’s outer diameter is less than 1 mm, the system is of potential for providing a more accurate assessment for pancreatic and bile duct cancers and even cardiovascular disease in clinical applications.
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