[Improved accuracy and precision of the automated shaver (navigated control) in functional endoscopic sinus surgery].
BACKGROUND
The feasibility of a navigate-controlled Shaver for the paranasal sinus surgery was proven in an initial study. Deficits showed up in the conversion of the planed cavity. Goal of this study is (1) the development and evaluation of a FESS demonstrator for the investigations to the surgical accuracy and (2) the evaluation of the resulting surgical accuracy for registration and conversion of the work space with an improved rigidity of the Shaver and a completely revised study design.


METHODS
As a demonstrator for the navigate-controlled resection of a volume through the Shaver a two-piece plastic head with an anatomical head and soft tissue model was designed. The investigation of the surgical accuracy takes place with 417 measurements to 4 different fiducial markers on the demonstrator head. The measurements for the deviation of the resulting cavity from the planned volume was realised with a work space by 24 x 24 x 30 mm. The 5 walls of the cavity were seized with 80 measuring points for each level and thus altogether 2000 measured values (5 models x 5 levels x 200 points).


RESULTS
The described demonstrator showed itself suitable for the close-to-application attempts to the surgical accuracy. The maximum deviation A (max) indicated position of the Shaver from the reference value amounted to 1,93 mm. The maximum average value of the exceeding of a planned cavity amounts to 1,62 mm.


CONCLUSIONS
Based on these results a virtual safety passage of 2.00 mm is sufficient. The study refers the clinical serviceability of the navigate-controlled Shaver in paranasal sinus surgery.
Strauss
G
G
Innovation Center Computer Assisted Surgery, Klinik und Poliklinik für HNO-Heilkunde/Plastische Operationen, Universität Leipzig, Liebigstrasse 18a, 04103 Leipzig. Gero.Strauss@medizin.uni-leipzig.de
Koulechov
K
K
Stopp
S
S
Strauss
M
M
Pankau
A
A
Hofer
M
M
Korb
W
W
Dietz
A
A
Meixensberger
J
J
Lüth
T
T
D004867:Equipment Design; D005240:Feasibility Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008437:Maxilla / Q000000981:diagnostic imaging / Q000601:surgery; D010256:Paranasal Sinuses / Q000000981:diagnostic imaging / Q000601:surgery*; D015203:Reproducibility of Results; D012984:Software; D025321:Surgery, Computer-Assisted / Q000295:instrumentation*; D013525:Surgical Instruments; D013673:Technology Assessment, Biomedical; D014057:Tomography, X-Ray Computed