Copyright © 2011 American Medical Association. All rights reserved. From: Navigated Surgery at the Lateral Skull Base and Registration and Preoperative ImageryExperimental Results Arch Otolaryngol Head Neck Surg. 2011;137(2):144-150. doi:10.1001/archoto.2010.249 Figure Legend: The measurement setup shows the specimen from the cranio-occipital region held by the 2 hydraulic arms that are securely attached to the Vogele-Bale-Hohner mouthpiece (not visible from this view). The locking acrylic dental splint, in addition, carries an external superstructure in close proximity to the left lateral skull base. Another hydraulic arm was used to eliminate hand tremor during measurements and to keep the pointer in place (shown as an example at measurement point 7). Date of download: 1/1/2018 Copyright © 2011 American Medical Association. All rights reserved.

Copyright © 2011 American Medical Association. All rights reserved. From: Navigated Surgery at the Lateral Skull Base and Registration and Preoperative ImageryExperimental Results Arch Otolaryngol Head Neck Surg. 2011;137(2):144-150. doi:10.1001/archoto.2010.249 Figure Legend: The specimen as viewed from the occipital region. A sample of measurement points (⊕) in and around the petrous bone is shown. The points were selected to provide optimum visibility in the computed tomographic data and on the specimen and comprise pneumatized cells of the mastoid, the vessels, or the most lateral edge of the truncated internal auditory canal. Note the internal auditory canal (IAC plus arrow), the internal carotid artery (ICA), the mastoid (M), and the sigmoid sinus (SS). Date of download: 1/1/2018 Copyright © 2011 American Medical Association. All rights reserved.

Copyright © 2011 American Medical Association. All rights reserved. From: Navigated Surgery at the Lateral Skull Base and Registration and Preoperative ImageryExperimental Results Arch Otolaryngol Head Neck Surg. 2011;137(2):144-150. doi:10.1001/archoto.2010.249 Figure Legend: Screenshot at a magnification of 400% from the navigation software (StP [Software Through Pictures] 4.0; Atego, San Diego, California). Multiplanar view showing axial, coronal, and sagittal cuts. The tip of the probe is on the most lateral part of the truncated internal auditory canal (measurement point 13) and is visualized as the crosshairs. No deviation in this measurement can be found. This screenshot represents the ideal application accuracy in the petrous bone (high-resolution petrous bone computed tomographic scan and registration with external fiducials plus anatomical landmarks). Date of download: 1/1/2018 Copyright © 2011 American Medical Association. All rights reserved.