The complete integration of spectral domain optical coherence tomography (SD-OCT) into an operating microscope now enables targeted, high-resolution imaging-guided vitreoretinal surgery. This provides real-time visualization of retinal layers, vitreous body and instrument-tissue interactions, which can be used for intraoperative decision making. Compared to conventional surgical microscopes, intraoperative OCT enables a greatly enhanced precision of vitreoretinal surgical maneuvers and is an essential prerequisite for the implementation of real-time guided surgical techniques at the micrometer level.