gms | German Medical Science

77th Annual Meeting of the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery

German Society of Oto-Rhino-Laryngology, Head and Neck Surgery

24.05. - 28.05.2006, Mannheim

Surface Laser Registration in ENT-Surgery: Accuracy in the Paranasal Sinuses – A Cadaveric Study

Meeting Abstract

German Society of Otorhinolaryngology, Head and Neck Surgery. 77th Annual Meeting of the German Society of Otorhinolaryngology, Head and Neck Surgery. Mannheim, 24.-28.05.2006. Düsseldorf, Köln: German Medical Science; 2006. Doc06hno093

The electronic version of this article is the complete one and can be found online at:

Published: September 7, 2006

© 2006 Stelter et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



Introduction: The reliability of image-guided surgery is determined by the localization accuracy of the navigation system. Navigational accuracy highly depends on the registration method. We assessed the accuracy after surface laser registration using the navigation system VectorVisionCompact (Brainlab, Heimstetten).

Materials and Methods: Measurements were performed on cadaver heads. Fiducials were placed in the paranasal sinuses and the lateral skull base fixed by titanium screws, thereby serving as measurement points more reliable than methods applied in previous studies [1], [2]. This procedure proved particularly advantageous as it allowed us to obtain exact accuracy values directly in areas of ENT-surgery. Furthermore, the respective influence on measurement accuracy depending on the choice of the registration area was evaluated.

Results: The accuracy of the navigation system after surface laser registration was acceptable: The resulting overall accuracy for a symmetrically bilateral surface registration was 1.13 ± 0.53 mm. Increasing distance between target point and registration area went along with a decline in accuracy. Measurement accuracy was significantly influenced by the choice of the registration area. Best accuracy was detected after symmetrically bilateral registration.

Conclusion: When choosing the registration area, care should be taken to use points for scanning that are symmetrically distributed and cover as much of the patient’s face as possible. It is decisive to consider the registration points when preparing the operation side. To gain the best results it may often be necessary to do the scanning before patient’s positioning and sterile covering.


Grevers G, Leunig A, Klemens A, Rasp G, Hagedorn H. Computerassistierte Chirurgie der Nasennebenhöhlen – Technologie und Klinische Erfahrungen mit dem Vector-Vision-Compact® System an 102 Patienten. Laryngorhinootologie 2002; 81:476-483.
Schlaier J, Warnat J, Brawanski A. Registration Accuracy and Practicability of Laser-Directed Surface Matching. Comp Aid Surg 2002; 7: 284-2