Noninvasive Imaging of Engineered Tissue

Development of constructs from naturally derived biocompatible smart materials bring novel possibilities for soft tissue engineering. Secondly, several synthetic bone substitutes from organic, inorganic, polymer, or ceramic-based materials are currently available for bone tissue engineering. Imaging engineered soft tissues and imaging engineered bone is difficult. Naturally derived materials are almost impossible to distinguish from adjacent soft tissues and  the close resemblance of the structure and composition of bone substitutes and natural bone makes it difficult, if not impossible, to clearly discriminate the materials. Nevertheless, non-invasive methods of monitoring can greatly assist in the understanding of the remodeling process, the effectiveness of the scaffold in regenerating and supporting tissues, and in the design and optimization of scaffolds.

Achievements in the field of in vivo visualization and follow-up methods have been limited. Plain radiography and computed tomography (CT) are the most employed techniques. On the other hand, recent developments in the field of magnetic resonance imaging (MRI) open the way to a completely new scenario of high-resolution visualization applications. Studies evaluating developed dual contrast agents, traceable with both CT and MRI as enhancers of bone tissue or soft tissue contrast will be discussed. Moreover, in vivo MRI imaging studies with hybrid prevascularized scaffolds will be presented demonstrating the functionality of the neovasculature and rapid anastomosis of the neovasculature in the construct with the host vasculature.