Effective Atomic Number and Energy Absorption in Tissues

Abstract

An X-ray absorption method, using Ross balanced filters, is applied to measure the effective atomic number of excised body tissues. The results are used to calculate linear absorption coefficients and the true energy absorption in ergs per röntgen for these tissues over a wide range of wavelength. Approximate methods of calculation are applied to determine the dosage throughout a heterogeneous medium and a number of examples, relevant to clinical treatments, are worked out on an energy absorption basis. The problem of dosage in bone is considered and an attempt is made to extend the specification of radiation dosage beyond that stated in terms of the röntgen.