Automated design and production of cranioplasty plates: outer surface methodology, accuracies and a direct comparison to manual techniques

AbstractLarge vulnerable openings in human cranium require a rigid anatomical reconstruction. A possible solution is the use of personalised thin titanium plates, also denoted membranes. The indirect production process, which is mainly hydroforming or casting, requires a single die, which is shaped manually or milled directly from a CAD-file.Currently, the design of membranes is mainly manual work, even with the use of CAD facilities, and results in a tedious and user-dependent skull reconstruction. A direct link between CAD-file and production is missing, and no studies evaluate the overall geometrical outcome quantitatively.This paper therefore presents an innovative automated design-methodology for custom-made cranioplasty plates. For a clinical case, the time durations and shape deviations are assessed and compared with results of the current artisanal design procedure. The afore-mentioned required improvements are achieved.

[1]  E Machtens,et al.  Custom-made cast titanium implants produced with CAD/CAM for the reconstruction of cranium defects. , 1999, International journal of oral and maxillofacial surgery.

[2]  Paul J. Besl,et al.  A Method for Registration of 3-D Shapes , 1992, IEEE Trans. Pattern Anal. Mach. Intell..

[3]  A D Linney,et al.  Validation of computer-assisted manufacture of titanium plates for cranioplasty. , 1999, International journal of oral and maxillofacial surgery.

[4]  K F Moos,et al.  Skull reconstruction with a two-part interlocking custom-made titanium plate. , 1999, The British journal of oral & maxillofacial surgery.

[5]  J. Vander Sloten,et al.  Design for medical rapid prototyping of cranioplasty implants , 2003 .

[6]  R. Hayward,et al.  Cranioplasty: don't forget the patient's own bone is cheaper than titanium. , 1999, British journal of neurosurgery.

[7]  J Vander Sloten,et al.  Semi-automated segmentation and visualisation of outer bone cortex from medical images , 2006, Computer methods in biomechanics and biomedical engineering.

[8]  David P. Dobkin,et al.  The quickhull algorithm for convex hulls , 1996, TOMS.

[9]  William E. Lorensen,et al.  Marching cubes: A high resolution 3D surface construction algorithm , 1987, SIGGRAPH.

[10]  R Van Audekercke,et al.  Medical image based, preformed titanium membranes for bone reconstructions: Design study and first clinical evaluation , 2002, Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine.