Depth-Based, Motion-Stabilized Colorization of Microscope-Integrated Optical Coherence Tomography Volumes for Microscope-Independent Microsurgery

Purpose We develop and assess the impact of depth-based, motion-stabilized colorization (color) of microscope-integrated optical coherence tomography (MIOCT) volumes on microsurgical performance and ability to interpret surgical volumes. Methods Color was applied in real-time as gradients indicating axial position and stabilized based on calculated center of mass. In a test comparing colorization versus grayscale visualizations of prerecorded intraoperative volumes from human surgery, ophthalmologists (N = 7) were asked to identify retinal membranes, the presence of an instrument, its contact with tissue, and associated deformation of the retina. In a separate controlled trial, trainees (N = 15) performed microsurgical skills without conventional optical visualization and compared colorized versus grayscale MIOCT visualization on a stereoptic screen. Skills included thickness identification, instrument placement, and object manipulation, and were assessed based on time, performance metrics, and confidence. Results In intraoperative volume testing, colorization improved ability to differentiate membrane from retina (P < 0.01), correctly identify instrument contact with membrane (P = 0.03), and retinal deformation (P = 0.01). In model microsurgical skills testing, trainees working with colorized volumes were faster (P < 0.01) and more correct (P < 0.01) in assessments of thickness for recessed and elevated objects, were less likely to inadvertently contact a surface when approaching with an instrument (P < 0.01), and uniformly more confident (P < 0.01 for each) in conducting each skill. Conclusions Depth-based colorization enables effective identification of retinal membranes and tissue deformation. In microsurgical skill testing, it improves user efficiency, and confidence in microscope-independent, OCT-guided model surgical maneuvers. Translational Relevance Novel depth-based colorization and stabilization technology improves the use of intraoperative MIOCT.