ABSTRACT
Acknowledgment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400
tissue, for example, cell aggregate size. Additional information can be obtained if coherent illumination is applied (usually from a laser) and the properties of the detected speckle are analyzed. e contrast of the detected speckle pattern can be related to the biomechanical properties of the tissue or the ow of blood cells within vessels. If illumination is performed using dierent colors, then tissue properties such as blood oxygen saturation can be imaged. e advantages of such approaches are that they are very robust and relatively simple, and so are well suited for long-term monitoring and automation of tissue-engineered processes. e drawback is that such macroscopic imaging is at low spatial resolution and is oen only carried out at the surface of the tissue, with no (or very little) depth discrimination.
