 The MI device is a novel unique device when compared to other spectroscopic devices used to study tissue transfer flaps. MI uses a non-contact optical imaging technology developed at the Beckman Laser Institute that has the unique capability of performing both diffuse optical tomography and rapid, wide-field quantitative mapping of tissue optical properties within a single measurement platform. While other non-contact spectroscopic devices use a time-modulation methods, MI alternatively uses spatially modulated illumination for imaging of tissue constituents. The MI system consists of 1 a light projection system that illuminates the tissue with spatial sinusoid patterns, and 2 a CCD camera, which collects the diffusely reflected light in a non-contact geometry. The wavelength of illumination can be selected by bandpass filtering of a broadband source i.e. tungsten lamp, or by use of a monochromatic source i.e. laser diode. Lastly, tissue fluorescence measurements can be performed by placing a combination of source-blocking and bandpass emission filters in front of the camera. 3, 11 