In many bedside procedures, surgeons must rely on their spatiotemporal reasoning to estimate the position of an internal target by manually measuring external anatomical landmarks. One particular example that is performed frequently in neurosurgery is ventriculostomy, where the surgeon inserts a catheter into the patient’s skull to divert the cerebrospinal fluid and alleviate the intracranial pressure. However, about one-third of the insertions miss the target. We, therefore, assembled a team of engineers and neurosurgeons to develop an interactive surgical navigation system using mixed reality on a head-mounted display that overlays the target, identified in preoperative images, directly on the patient’s anatomy and provides visual guidance for the surgeon to insert the catheter on the correct path to the target. We conducted a user study to evaluate the improvement in the accuracy and precision of the insertions with mixed reality as well as the usability of our navigation system. The results indicate that using mixed reality improves the accuracy by over 35% and that the system ranks high based on the usability score.