A device and method for guided insertion of microelectrodes into tissue is provided. The device includes a flexible optical fiber for optical coherence tomography imaging, a metal layer coating the optical fiber for recording electrical signals and an outer insulation layer coating the metal layer along the optical fiber length. The method includes inserting an optical fiber coated with a metal layer and further coated with an insulation layer into a tissue, collecting intraoperative image data through the optical fiber by optical coherence tomography, receiving the image data on a computer and displaying the image on a monitor, using the image data to determine a location in the tissue, receiving an electrical nerve signal through the metal layer and measuring the electrical nerve signal on a electrophysiological recording system.