'Determination of the mass attenuation coefficient for the contrast agent Iohexol using 662 keV photons from a Cesium-137 source'.

摘要

Iohexol is an iodinated chemical compound (C19 H26I3N3O9) which is currently used as a contrastagent in x-ray radiography. Due to its composition including iodine has the property to enhance the attenuationof photons in the biological material in which has been injected. This work is part of a more extensive study todetermine the optimal dilution of Omnipaque (Iohexol) in serum providing good images with minimal toxiceffects and less radiation dose to individuals. Here, results of an experimental determination of its massattenuation coefficient at dilutions of 50% and 100 % performed at energies of 662 keV provided by a Cs-137source, and 59.5 keV from an Am-241, are presented. Measurements were performed using calibrated gammasources and a standard gamma spectroscopy system available at the nuclear physics laboratory of the Faculty ofSciences, University of Chile. As quality control the attenuation coefficient for water was determined at bothenergies finding an agreement with accepted values within 2 %. The system was also checked at 662 keV withlead sheets obtaining similar agreement with values in tables and computer codes. For a dilution to 50% ofIohexol the attenuation coefficient is reduced to 61 % at the energy of 59.5 keV. Calculations made with thecomputer code XCOM for Omnipaque at 100% at both energies were close the experimental values within 2 %.