Jorge Vicente Lopes da Silva, MSc¹; Ailton Santa Bárbara, MSc¹; Silvia Helena Cardoso, PhD²,  Renato M. E. Sabbatini, PhD² and Norberto Cysne Coimbra, MD, PhD³

¹CenPRA- “Renato Archer” Research Center. ²Center for Biomedical Informatics, State University of Campinas and  ³School of Medicine, University of São Paulo at Ribeirão Preto, São Paulo, Brazil.

Application of rapid prototyping technologies using SLS (Selective Laser Sintering) in medicine is a new and exciting field created by the convergence of three different technologies: medical imaging acquisition, computer graphics and rapid prototyping. Medical images in digital format are obtained by the use of CT and MRI tomography. We have used these technologies at CenPRA for rapid prototyping of human skulls for reconstructive surgery planning. In this paper we explore the production of accurate 3D models by SLS for teaching anatomy.

The teaching of anatomy has been hindered by the lack of anatomically accurate 3D models. Rapid prototyping using selective laser sintering (SLS) replicate virtual 3D models in a physical touch-and-feel prototype [1], and efficiently integrates with medical images and specialized software. The plastic physical model (fig.1) can be used for surgery planning and rehearsal, improving communication and planning of highly complex surgeries, as well as for patient education.

In this project we have been using CT slices from the Visible Human Database (US National Library of Medicine). Our initial project involves operator assisted semi-automatic segmentation of the brain in order to use the resulting models to teach neuroanatomy at undergraduate level.

The main objective of the segmentation process is to achieve an accurate 3D model incorporating an assembly of a brain parts with accurate reproduction of soft tissue structure using opaque polyamide plastic.

Figure 1. Partial model of a skull developed by selective laser sintering

Technical problems which have been addressed in the initial phase were: soft tissue segmentation algorithm, optimal parameters for transference to the SLS device software, the model’s surface smoothing mass scale reproducibility of produced models.

The resulting models will be used and evaluated by the authors in a real world situation for teaching neuroanatomy for first-year medical and nursing students.

Reference

[1] Webb, P.A. (2000), ``A review of rapid prototyping (RP) techniques in the medical and biomedical sector’’, J Med Eng Technol, 24 (4):, 149-53