Automated Design and Production of Cranioplasty Plates: Outer Surface Methodology, Accuracies and a Direct Comparison to Manual Techniques

Large 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.