Purpose To report the 3-year assessment of feasibility and usefulness of microscope-integrated intraoperative OCT (iOCT) during ophthalmic surgery. Design Prospective, consecutive case series. Participants Adult participants undergoing incisional ophthalmic surgery with iOCT imaging who consented to be enrolled in the Determination of Feasibility of Intraoperative Spectral-Domain Microscope Combined/Integrated OCT Visualization during En Face Retinal and Ophthalmic Surgery (DISCOVER) study. Methods The DISCOVER study is a single-site, multisurgeon, institutional review board-approved investigational device prospective study. Participants included patients undergoing anterior or posterior segment surgery who underwent iOCT imaging with 1 of 3 prototype microscope-integrated iOCT systems (i.e., Zeiss Rescan ...