SynDaver’s products may be substituted for traditional models in such tests by virtue of their similarity to the actual-use environment. This resemblance is characterized by a matching of mechanical, physical and chemical properties, geometry and organ-to-organ interaction. On the simplest level, individual synthetic organs (rectus femoris muscle, small intestine, abdominal aorta, etc.) are constructed so that they replicate the geometry (shape, diameter, wall thickness, etc.) of a particular portion of the target anatomy. In addition, the individual synthetic tissue analogs used to fabricate these components are formulated to exhibit chemical and physical properties (water, salt and fiber content, strength or modulus in shear, coefficient of static or dynamic friction, surface energy, dielectric properties, heat capacity, porosity, etc.) that mimic the properties of the target tissue. Finally, the model components are assembled in such a way that the interaction between adjacent components is similar to that expected in the target tissue. That is, the body part is designed so that inter-facial properties, such as the coefficient of dynamic friction (inter-organ) as well as the mechanical attachments, mimic those exhibited in the target anatomy.
To design these synthetic body parts, the anatomy to be simulated must be conceptually divided into discrete sections that will form the basis of the model. For example, a very simple model of the thoracic aorta might be separated into two parts: the first consisting of the artery itself and the second of the surrounding tissues. At least two (and possibly many more) tissue analogs would then be designed for the fabrication of this model. In this case, one tissue analog would be required for the artery component, and the other would be used to construct the supporting tissue component. Of course, models require more than two tissue components to accurately simulate the response of the target anatomy, and each of these components would typically employ three or more tissue analogs. SynDaver’s elastic arteries, for example, employ separate tissue analogs for intima, media and adventitia, with each of these layers composed of multiple materials.