A non-powered, noninvasive component of a surgical navigation and/or device tracking system (e.g., computer-assisted surgical ultrasound system, surgical microscope) intended for preoperative and/or intraoperative use to function as an optical reference to enable spatial registration/tracking of the position/movement/size of a patient, another marker and/or surgical instrument (e.g., stereotactic surgery probe). It may be attached to the patient, another marker or surgical instrument, and may contain features (e.g., reflective spheres, contrast patterns) detectable by a tracking camera. Procedural supportive devices (e.g., drapes) may be included with the device. This is a single-use device.