Investigations on tissue equivalence of selected biomaterials through radiological parameters

Abstract

The objective of this work is to investigate some commonly available tissue mimicking biomaterials for imaging phantoms and different radiation therapies utilizing gamma-photons, protons, electrons and neutrons. The various interaction parameters employed in radiology like computed tomography number, buildup factor, mass attenuation coefficient, stopping power and fast removal cross-section have been computed through various software programs namely Phy-X/PSD, XCOM, SRIM and NIST: ESTAR database. The mass attenuation coefficient values obtained from the two methods i.e. Phy-X/PSD and XCOM support each other with maximum relative difference of 1%, thus validating the use of new software for biomaterials. The tricalcium phosphate and monocalcium phosphate anhydrous are found to be the best phantom material having attenuation values 0.410 and 0.319 cm2/g and computed tomography numbers 5225.3 and 2426.1 at photon energy 59.5 keV, which are in good harmony with that of enamel and cortical bone respectively. Similarly, dicalcium phosphate anhydrous/monocalcium phosphate monohydrateare appropriate biomaterials for enamel/cortical bone over useful MeV energy range for electron as well as neutron therapy.