PATIENT EXPOSURES FROM DIAGNOSTIC RADIOLOGICAL PROCEDURESIN INDIA

摘要

It is very well recognised that the ratio of diagnostic information / patient dose must be optimised in diagnosticrnradiology for each type of examination. Regulatory authorities in various countries are now engaged in developingrndose constraint values for various X-ray examinations. In a co-ordinated research project, Atomic EnergyrnRegulatory Board (AERB) and Bhabha Atomic Research Centre (BARC), India, conducted a nationwide surveyrnto assess the impact of diagnostic radiological practices on population dose in the country. Forms were designedrnto collect data on :-(I) X-ray examinations, (ii) details of X-ray machines, (iii) type of work and workload inrndifferent hospitals, and (iv) X-ray examination techniques and associated technical parameters. Entrance skinrndoses were estimated by using specially designed and calibrated TLD postal packs. The entrance skin dose wasrnestimated for a particular examination in a hospital on the basis of TL reading of disc under perspex filter, takingrninto account the focus-to-skin distance, back-scatter factor, the mass energy absorption coefficient and the mAsrnactually used for the examination. The analysis of entrance skin doses estimated for 12 common X-ray proceduresrnin these 40 hospitals showed that for the most part these doses fall within the reference levels specified in thernBasic Safety Standards (BSS).