Ultrasound imaging of the posterior skull for neurosurgical registration

PURPOSE: Neurosurgical registration using optical tracking in prone position is problematic due to a lack of anatomical landmarks on the posterior skull. The current method of registration involves insertion of screws into the skull. Surface registration using ultrasound has been proposed as a less invasive method of registration. Obtaining full access to the posterior skull would require patient hair removal, which is not favored by patients as it can cause an increased risk of surgical site infection and a less aesthetic outcome. We performed ultrasound scans on participants with no hair removal to evaluate the visibility of the mastoid processes and occipital base of the posterior skull in ultrasound imaging.