A Non Invasive Tomography System for Characterization and Visualization of Tissue Optical Phantoms

Optical imaging techniques are treated with utmost importance due to their noninvasive and relatively inexpensive qualities. They have obvious advantages for continuous monitoring of physiological changes over diagnostic modalities like radiography and computed tomography which utilizes ionic radiation. Tomography is mathematical technique to get cross sectional details of an object from multiple trans-axial projections. A projection is a shadowgram obtained by illuminating a specimen by a penetrating radiation. In the proposed system the specimen is illuminated by using a near infrared laser and the transmitted optical radiation from the specimen are analyzed. Within the therapeutic window, from 600-1100 nm range tissues remain relatively transparent which helps to apply tomographic principles in obtaining the cross sectional details. The developed system was tested for its imaging capabilities as well as detection of abnormalities by using tissue mimicking structures called phantoms. Finally by using volume visualization techniques 3D visualization of the phantoms are also observed. Keywords—Optical imaging, Shadowgram, Tomography, Transillumination, Volume visualization.