Measurement of small-angle photon scattering for some breast tissues and tissue substitute materials

For photon energies encountered in diagnostic radiology the shape of the scattering distributions for low-atomic-number media exhibits peaks in intensity close to the forward direction not predicted by conventional theoretical models. The peak positions and shapes depend upon interatomic and intermolecular configurations of the scatterers. The phenomenon is relevant to the understanding and modelling of X-ray imaging processes and peaking may be characteristic of tissue type. Peaks in the forward scattering distributions have been demonstrated for 19 samples of breast tissue and three tissue substitute materials using a position-sensitive photon detector and a 60 kVp X-ray source. Prominent features were observed for all samples investigated. Large differences were found in the shapes of the distributions between adipose and fibroglandular tissues and only small differences between carcinomas and fibroglandular tissues. (author)