كنترل كيفي دستگاه هاي راديولوژي تشخيصي بيمارستان هاي استان چهار محال وبختياري

Quality control of the radiological equipment in Chaharmahal & Bakhtiari Hospitals

Diagnostic radiology is one of the most useful applications of radiation in the world. To reduce unnecessary exposure in this imaging modality, implementation of a quality control (QC) program is vital. In this study, to reduce absorbed dose and to increase the image quality, various QC parameters were evaluated for x-ray machines consisting of kilo volt peak (KVp), milli-ampere (mA), exposure time (ms), focal film distance (FFD), inherent filters, additional filters, half value layer (HVL) and processor condition. To apply these parameters seven x-ray machines in six diagnostic radiological centers were selected and were kept under QC program. To compare the doses before and after implementation of QC programs chest x-ray examination was done on 10 randomly selected ʹpatients for each machine.The dosimetry showed that the average entrance skin dose (ESD) for each chest x-ray examination was 0.7 mGy before application of QC program. The average absorbed dose for chest examination was %40 after application of the program. Number of patients under radiological examination is about 500,000 persons. If a similar QC program was exactly performed in all diagnostic centers of this province, the collective dose will be reduced to (500000x0.28 mGy) =140 Man-Sievert. Therefore, by implementation of a QC program, the absorbed dose and cancer risk resulted from diagnostic radiology will be effectively reduced.