Characterization of engineered tissue construct mechanical function by magnetic resonance imaging

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Tissue Engineering

Background:

• Engineered tissues require mechanical function assessment for successful regeneration.
• Articular cartilage, spine, and heart regeneration rely on mechanical endpoints.
• Non-invasive magnetic resonance imaging (MRI) characterizes tissue physical phenomena.

Purpose of the Study:

• To demonstrate MRI application for characterizing engineered tissue mechanical function.
• To utilize phase contrast-based MRI for detailed deformation field analysis.
• To correlate mechanical properties with extracellular matrix composition.

Main Methods:

• Applied phase contrast-based MRI to an articular cartilage defect model.
• Characterized detailed deformation fields within native and engineered tissues.
• Assessed glycosaminoglycan ([GAG]) concentration using gadolinium-enhanced MRI.

Main Results:

• MRI revealed non-uniform strain fields varying with spatial position.
• Tissue constructs exhibited higher strains than surrounding native cartilage.
• [GAG] concentration was lowest in tissue constructs and varied spatially.

Conclusions:

• MRI provides complementary data on tissue mechanical function.
• Deformation relates to tissue geometry, extracellular matrix, and integration.
• Advanced MRI phase contrast methods are valuable for evaluating engineered tissues.