NIR Reflectance Imaging of Biological Tissue Using Multiple Sources and Detectors

Purpose Near-infrared optical imaging system is a developing optical method which examines biological tissues inside the body non-invasively. This technology can be facilitated for continuous diagnosis and monitoring of biological tissues as they use non-ionizing light photons. In this paper, the design and development of a reflectance type optical system which could be used for brain imaging is discussed. Procedure The system consists of a flat-imaging patch with two LEDs operating at 695 nm surrounded by 32 detectors together forming double-layered octal geometry, the preprocessing unit and the NI-DAQ card interfaced with the PC. Tissue-equivalent phantoms were prepared using paraffin wax with objects of size 5 mm embedded at depths 7 and 14 mm was made. The developed optical reflectance system was placed on it for data acquisition. The data acquired was interpolated and filtered and displayed as images. Results The images constructed show the presence of the embedded objects in the phantom located at different depths from which their approximate location can also be obtained. Conclusion This system if made with more sources and detectors to cover a larger area can be used for monitoring the brain function in premature babies, intravascular hemorrhages and hypoxic-ischemia.