Abstract
This study aimed to measure entrance surface air kerma (ESAK, in mGy) during routine skull X-ray examinations of adult patients and to establish a local diagnostic reference level (LDRL) in the diagnostic radiology department of King Khalid Hospital in Majmaah. The patient's ESAK, mGy and effective dose (ED, in mSv) at the 75th percentile were calculated based on the output of the X-ray tube and the exposure parameters, as well as the use of suitable conversion coefficients, respectively. To calculate the ED and patient's ESAK, the output and exposure characteristics of the X-ray tube and relevant conversion coefficients were considered (ESAK). Additionally, the 75th percentile distributions for the ESAK and KAP distributions were calculated. A wide range of ESAK was observed, which might be due to the difference in the exposure factors applied for each examination. The mean values of ESAK and KAP together with 75th percentiles for Anteroposterior (AP) and lateral skull projection were 0.22 (0.10-0.30) mGy, 0.24 (0.0.18-0.25) mGy and 0.21 (0.19-0.26) Gy.cm(2), 0.29 (0.17-0.32) Gy.cm(2), respectively. The findings were significantly lower than national reference levels, the most reported European DRL values, and other previously reported dose values. The measured ESAK and KAP were within the recommended and acceptable dose limits. The best radiation protection can be achieved by optimizing the radiation dose while preserving image quality.