On the intricacy of imaging with incoherently-scattered radiation

Imaging with incoherently-scattered radiation has been promoted for many years as an alternative to the conventional process of radiography and computed tomography with transmitted radiation. Scatter imaging resembles natural vision, needs only frontal access to the object, provides point-wise differential information and can determine directly the density of an object without inference from the attenuation coefficient. Nevertheless, in spite of many decades of development effort, since the technique was first introduced by Lale [P.G. Lale, Phys. Med. Biol. 4 (1959) 159], the scatter imaging modality has not prevailed. This paper tracks the development of this imaging modality, presents some recent advances and outlines the remaining challenges.