Paper RADIATION DOSIMETRY FOR EXTREMITY RADIOGRAPHS

The energy imparted, ε, to a patient undergoing an extremity x-ray examination may be obtained from the dosearea product incident on the patient. Values of energy imparted can be subsequently converted into the corresponding effect ive dose , E, us ing an extremity spec i f i c EIε rat io . In th i s study, an E/ε ratio of 3 mSv/J was used to convert values of energy imparted into the corresponding upper limit of adult effective doses for all types of extremity examinations. A modification factor, based on the patient mass, was employed to determine the corresponding extremity effective doses to pediatr ic pat ients undergoing extremity examinat ions . Representat ive c l in ica l technique factors for s ix common extremity examinat ions (hand, forearm, e lbow, ankle , tibia/fibula, knee) were used to determine the dose-area product and the corresponding values of energy imparted. For adult extremity x-ray examinations, values of energy imparted ranged from 55 μJ to 920 ,LI, with the energy imparted to l-y-old patients being a factor of about 20 lower. Upper limits of effective doses for adult extremity x-ray examinations ranged from 0.17 to 2.7 μSv, whereas the corresponding doses to l -y-o ld pat ients were about a factor of three lower. Health Phys. 75(5):492-499; 1998