Article
Improved pre-operative planning with Rapid Prototyping of the Laterobasis
Verbesserte OP-Planung mittels Rapid Prototyping der Laterobasis
Search Medline for
Authors
-
Ronny Grunert
- Innovation Center Computer Assisted Surgery, University of Leipzig, Leipzig, Germany
-
Mathias Hofer
- Department of Otorhinolaryngology/Plastic Surgery, University of Leipzig, Leipzig, Germany
-
Werner Korb
- Innovation Center Computer Assisted Surgery, University of Leipzig, Leipzig, Germany
-
Hendrik Moeckel
- Innovation Center Computer Assisted Surgery, University of Leipzig, Leipzig, Germany
-
Mario Thalheim
- Innovation Center Computer Assisted Surgery, University of Leipzig, Leipzig, Germany
-
Gero Strauss
- Department of Otorhinolaryngology/Plastic Surgery, University of Leipzig, Leipzig, Germany
-
Juergen Meixensberger
- Department of Neurosurgery, University of Leipzig, Leipzig, Germany
-
Christos Trantakis
- Department of Neurosurgery, University of Leipzig, Leipzig, Germany
-
Andreas Dietz
- Department of Otorhinolaryngology/Plastic Surgery, University of Leipzig, Leipzig, Germany
| Published: | September 7, 2006 |
|---|
Outline
Text
Purpose: For a patient with over years persisted otorrhea and well-retentived hearing situation, a patient individ-ual anatomical correct RPT-model was created (Figure 1 [Fig. 1]). The aim was to decide with the help of the 3D Rapid Prototyping Model (RPT-model) which instrument path is optimal to perform the surgical inter-vention organ preserving as possible. Material and methods: Based on CT-images (Somatom Volume Zoom; Siemens, Erlangen Germany) with a layer thickness of 0.5 mm regions of interests were segmented using the software Mimics 9.0 (Materialise, Leuven, Belgium). The segmented regions are the target volume (cholesteatoma), structures at risk (facial nerve, artery carotis interna, sinus sigmoideus) and anatomical structures for orientation (petrous bone).
After the segmented area of the original patient dataset was transferred into an STL-file, the file was sent to the 3D printer Z510 (4D Concepts, Gross-Gerau, Germany). The building material is based on plaster. Subsequently the printed model was infiltrated with polyurethane and acetone to influence the material properties.
To determine the accuracy of the 3D RPT-models, 15 3D RPT-models based on the same segmented original patient dataset were created and compared with the software Polyworks 9.0 (InnovMetric Soft-ware Inc, Sainte-Foy, Canada).
A simulation system including the patient individual RPT-model can be used to perform the milling procedure with the real surgical instrument. The system detects the contact between surgical instru-ment and structure at risk during the simulation procedure (Figure 2 [Fig. 2]).
Results and conclusion: A patient individual 3D RPT-model (scale 1:1) for a patient having a cholesteatoma in the region of the lateral skull base was created. The RPT-model was the base for discussions with colleagues of the department of neurosurgery for improved preoperative planning.
An accuracy study of 15 identical RPT-models compared to the CT-dataset shows that the mean ac-curacy is (0.101 ± 0.077) mm, with maximum and minimum values of +0.380 mm and -0.272 mm.
Implementing the RPT-model in a simulation system, it is possible to detect contact between struc-tures at risk and surgical instrument during the simulation procedure.
Compared to other RPT-technologies the presented 3D-printing based on plaster allows creation of cost-efficiently RPT-models.
The 3D RPT-model representation is qualified for preoperative planning of complex surgical interven-tions, occurring in the region of nerves and vessels near the base of the skull.
