Virtual intraoperative optical coherence tomography angiography integrated surgical microscope for simultaneous imaging of morphological structures and vascular maps in vivo

Intraoperative surgical microscopy integrated with optical coherence tomography (OCT) has improved the accuracy and safety of surgeries by providing a visualization of the sub-surface tissue structure. Although intraoperative OCT has resolved the conventional limitations of the surgical microscope, it is still remained to provide additional informative blood vessel-related data that is required to enhance the stability of surgery by minimizing bleeding and tissue damage. In this paper, we developed a virtual intraoperative OCT angiography integrated surgical microscope (VI-OCTA-SM) to simultaneously visualize morphological tissue structure and microvasculature data of the surgical region including tumor margin and blood vessel map. In addition, cross-sectional OCT and OCTA images and a three-dimensional maximum amplitude projection OCTA vascular map are concurrently displayed on the ocular eyepiece by augmented reality. The results of VI-OCTA-SM-based in-vivo imaging of mouse tissue (ear and brain) with different magnifications confirmed the capability of the VI-OCTA-SM to perform microvasculature imaging of small animals with an adjustable lateral resolution and scanning range according to the experimental conditions. Moreover, we successfully conducted melanoma resection as a simulated surgery following the guidance of the VI-OCTA-SM, which verified the applicability of the developed system to the surgical environment. Our proposed VI-OCTA-SM system has promising potential in various intraoperative applications including dermatological, ophthalmological, and neurological surgeries.