The Use of Rapid Prototyping in Clinical Applications

This chapter will present a brief overview of the possible applications of rapid prototyping in the medical context. Different options of clinical inputs will be discussed as well as five detailed case studies which will demonstrate the flexibility and clinical usefulness of this technique. Rapid prototyping broadly indicates the fabrication of a three-dimensional (3D) model from a computer-aided design (CAD), traditionally built layer by layer according to the 3D input (Laoui & Shaik, 2003). Rapid prototyping has also been indicated as solid free-form, computer-automated or layer manufacturing (Rengier et al., 2008). The development of this technique in the clinical world has been rendered possible by the concomitant advances in all its three fundamental steps: 1. Medical imaging (data acquisition), 2. Image processing (image segmentation and reconstruction by means of appropriate software) and 3. Rapid prototyping itself (3D printing). These steps are visually summarised in Figure 1. In clinical terms, the possibility of observing, manipulating or manufacturing an anatomical model can serve a range of significant functions (Kim et al., 2008). For instance, it can address visualisation issues that virtual examination cannot always resolve. Also, it can be adopted as a simulation tool or a teaching device. Moreover, it allows medical practitioners and researchers to fully make use of the “patient-specific” concept, in terms of prosthesis design and implant fitting but also in terms of ad hoc simulations. Finally, it can facilitate the communication between the clinician and the patient. The functions of rapid prototyping in the current clinical world are several (Adler & Vickman, 1999):  Pre-surgical planning: A 3D model not only can be useful in surgical practice (i.e. a better fitting, purposefully designed implant), but it can also help a surgical team in visually analysing the location, size and shape of the problem. In the event of a long operation, the model can also be used to plan and customise the surgery. This can be especially valuable when the surgery is performed on anatomical abnormalities.  Mechanical replicas: A 3D model can be tailored to specific material properties, including non-homogenous variations within a region. Specifically, mechanically