DETERMINATION OF ENTRANCE SURFACE DOSE FOR THREE COMMON PLANAR DIAGNOSTIC X-RAY EXAMINATIONS.

Patient dose during diagnostic radiography procedures primarily depends on the entrance surface dose (ESD) and the exposure area. The purpose of this study was to determine ESD for five common diagnostic X-ray examinations using dose area product and X-ray tube output. The ESDs were estimated in a sample of 340 patients using normalised X-ray output from Philips-PrimaryDiagnost digital X-ray machine equipped with digital flat panel scintillator detector. The resultant mean ESDs for chest postero-anterior/lateral, lumbar spine antero-posterior (AP)/lateral and abdomen AP were 0.49, 2.00, 5.74, 12.79 and 4.62 mGy, respectively. The mean and third quartile ESD values of this study were significantly higher than the values found in the literature. This can be attributed to the lower tube potential (kVp) values and the higher tube current-time products (mAs). The methodology used here is a better option for low-resources countries for routine dose monitoring.