MO-B-330A-01: Patient Radiation Doses in Diagnostic Imaging

Abstract

The main goal of this presentation is to discuss factors which affect patient radiationdose delivered during various diagnostic radiology imaging examinations and to relate these radiationdoses to potential biological risks. Measurement methods to estimate patient radiationdoses and some examples of dose reduction for radiography,mammography,fluoroscopy,angiography and CT will be reviewed. Applications of these measurements to patient dose estimation will be shown. Procedures to obtain quick computational estimates of patient doses for IRB submissions, patient inquiries and fetal dose estimations will be provided. Approaches to convert entrance skindoses,dose area products and dose length products to effective doses and risks will be discussed. Typical patient radiationdose values for common diagnosticimaging procedures will be given. Limitations, uncertainties and ranges for patient radiationdose estimates will be examined. The utilization of “reference values” for patient radiationdoses will be reviewed. Some guidelines to aid physicists with relating radiationdose issues to the public and informational media will also be included. The material is intended to provide a brief overview of one crucial aspect of the responsibilities with which diagnosticmedical physicists and medical health physicists must routinely handle in their jobs. Our expectation is to stimulate introspective assessments and to expand the manner in which patient radiationdose determinations are viewed and performed. Educational Objectives: 1. To review fundamental X‐ray dosimetry quantities. 2. To identify important factors that affect patient dose delivered by various X‐ray imaging modalities. 3. To describe common methods to measure patient dose and review strategies in developing patient dose charts for routine diagnosticimaging procedures. 4. To examine the limitations of some current dosimetry methodologies. 5. To present a practical guidance to physicists in providing day‐to‐day clinical support service such as IRB submissions, patient inquiries and fetal dose estimations.