Image-Guided Tissue Engineering of Anatomically Shaped Implants via MRI and Micro-CT Using Injection Molding

Abstract

This study demonstrates for the first time the development of engineered tissues based on anatomic geometries derived from widely used medical imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI). Computer-aided design and tissue injection molding techniques have demonstrated the ability to generate living implants of complex geometry. Due to its complex geometry, the meniscus of the knee was used as an example of this technique's capabilities. MRI and microcomputed tomography (microCT) were used to design custom-printed molds that enabled the generation of anatomically shaped constructs that retained shape throughout 8 weeks of culture. Engineered constructs showed progressive tissue formation indicated by increases in extracellular matrix content and mechanical properties. The paradigm of interfacing tissue injection molding technology can be applied to other medical imaging techniques that render 3D models of anatomy, demonstrating the potential to apply the current technique to engineering of many tissues and organs.

Long-Term Morphological and Microarchitectural Stability of Tissue-Engineered, Patient-Specific AuriclesIn Vivo

“…32 Briefly, three samples were collected from each of the frozen 6-month ears, previously studied 1-and 3-month ears, 25 and native juvenile bovine ears. Samples were weighed, refrozen, lyophilized, and weighed again.…”

“…Resultant stresses were recorded at 1 Hz and the temporal profiles of stress were fit to a poroelastic model of tissue behavior using custom MATLAB (MathWorks, Natick, MA) code to calculate the equilibrium modulus and hydraulic permeability. 32 …”

Non-Invasive analysis of synthetic and decellularized scaffolds for heart valve tissue engineering

“…27 In fact for several years, µ-CT has been a standard tool for biomechanical evaluation and optimization in orthopedic surgery. Jaecques et al 28 even examined the postimplantation adaptation of bone tissue by µ-CT.…”

Meniscus repair and regeneration: review on current methods and research potential

“…Their semi-liquid nature allows engineering anatomic geometries derived from medical imaging techniques, such as computed tomography or magnetic resonance, by the use of custom-printed moulds (Ballyns et al, 2008). Promising results were reported with alginate (Ballyns et al, 2010;Ballyns et al, 2008) and polyvinyl alcohol (PVA) (Kobayashi et al, 2003;Kobayashi et al, 2005). However, despite their wide implementation in cartilage tissue engineering they have been hardly utilised for meniscus engineering.…”

“…In particular, because of its complex geometry, meniscus engineering can benefit from computer-aided design and tissue injection moulding techniques. Ballyns et al (2008) demonstrated the feasibility of this approach by engineering a critically sized meniscus with bovine and ovine fibrochondrocytes suspended in agarose hydrogel. Even if the cells were not of human origin, this is an important proof of principle, opening new possibilities in meniscus tissue engineering.…”