An intraoperative probe and a system for optically imaging a surgically significant volume of tissue or other scattering medium. An illumination source generates an illuminating beam that is conveyed to the vicinity of the tissue and a beam splitter, that may be no more than an optical phase reference, splits the illuminating beam into a sample beam along a sample beam path and a reference beam along a reference beam path. A scanning mechanism scans a portion of the sample beam across a section of the scattering medium, while a detector detects return beams from both the reference beam path and the sample beam path and generates an interference signal. A processor computationally moves an effective focus of the sample beam without physical variation of focus of the sample beam. The probe may have a sterilizable fairing that may be detachable.