title: A novel navigation system for maxillary positioning in orthognathic surgery: Preclinical evaluation.
abstract: Appropriate positioning of the maxilla is critical in orthognathic surgery. As opposed to splint-based positioning, navigation systems are versatile and appropriate in assessing the vertical dimension. Bulk and disruption to the line of sight are drawbacks of optical navigation systems. Our aim was to develop and assess a novel navigation system based on electromagnetic tracking of the maxilla, including real-time registration of head movements. Since the software interface has proved to greatly influence the accuracy of the procedure, we purposely designed and evaluated an original, user-friendly interface. A sample of 12 surgeons had to navigate the phantom osteotomized maxilla to eight given target positions using the software we have developed. Time and accuracy (translational error and angular error) were compared between a conventional and a navigated session. A questionnaire provided qualitative evaluation. Our system definitely allows a reduction in variability of time and accuracy among different operators. Accuracy was improved in all surgeons (mean terror difference = 1.11 mm, mean aerror difference = 1.32°). Operative time was decreased in trainees. Therefore, they would benefit from such a system that could also serve for educational purposes. The majority of surgeons who strongly agreed that such a navigation system would prove very helpful in complex deformities, also stated that it would be helpful in everyday orthognathic procedures.
authors.affiliation: Maxillofacial and Plastic Surgery Department (Head: C. Bruant-Rodier, MD, PhD), Strasbourg University Hospital, 1, place de l'Hôpital, 67091 Strasbourg Cedex, France; IRCAD, Computer Science Research and Development Department (Head: L. Soler, PhD), 1, place de l'Hôpital, 67091 Strasbourg Cedex, France; ICUBE-CNRS - Fédération de Médecine Translationnelle de Strasbourg (FMTS), UMR 7357 - Engineering, Computer Science and Imaging Laboratory (Head: Y. Rémond, PhD), Télécom Physique Strasbourg, 300, Boulevard Sébastien Brant - CS 10413, 67412 Illkirch Cedex, France. Electronic address: jean-christophe.lutz@chru-strasbourg.fr.
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Lutz
authors.affiliation: IRCAD, Computer Science Research and Development Department (Head: L. Soler, PhD), 1, place de l'Hôpital, 67091 Strasbourg Cedex, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Nicolau
authors.affiliation: IRCAD, Computer Science Research and Development Department (Head: L. Soler, PhD), 1, place de l'Hôpital, 67091 Strasbourg Cedex, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Agnus
authors.affiliation: Maxillofacial and Plastic Surgery Department (Head: C. Bruant-Rodier, MD, PhD), Strasbourg University Hospital, 1, place de l'Hôpital, 67091 Strasbourg Cedex, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Bodin
authors.affiliation: Maxillofacial and Plastic Surgery Department (Head: C. Bruant-Rodier, MD, PhD), Strasbourg University Hospital, 1, place de l'Hôpital, 67091 Strasbourg Cedex, France.
authors.forename: Astrid
authors.initials: A
authors.lastname: Wilk
authors.affiliation: Maxillofacial and Plastic Surgery Department (Head: C. Bruant-Rodier, MD, PhD), Strasbourg University Hospital, 1, place de l'Hôpital, 67091 Strasbourg Cedex, France.
authors.forename: Catherine
authors.initials: C
authors.lastname: Bruant-Rodier
authors.affiliation: ICUBE-CNRS - Fédération de Médecine Translationnelle de Strasbourg (FMTS), UMR 7357 - Engineering, Computer Science and Imaging Laboratory (Head: Y. Rémond, PhD), Télécom Physique Strasbourg, 300, Boulevard Sébastien Brant - CS 10413, 67412 Illkirch Cedex, France.
authors.forename: Yves
authors.initials: Y
authors.lastname: Rémond
authors.affiliation: IRCAD, Computer Science Research and Development Department (Head: L. Soler, PhD), 1, place de l'Hôpital, 67091 Strasbourg Cedex, France.
authors.forename: Luc
authors.initials: L
authors.lastname: Soler
mesh_terms: D055590:Electromagnetic Phenomena; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008437:Maxilla / Q000601:surgery*; D008953:Models, Anatomic; D056948:Orthognathic Surgical Procedures / Q000379:methods*; D012984:Software; D025321:Surgery, Computer-Assisted / Q000379:methods*; D014584:User-Computer Interface
keywords: Computer-assisted surgery; Electromagnetic tracking; Navigation; Orthognathic surgery