Investigation on entrance surface doses to adult patients from medical X-ray examination in Henan province

Abstract

Objective To investigate the levels of the entrance surface doses to adult patients from X-ray examinations in Henan province, and to provide technical and data support for establishing the dose guidance level of diagnostic radiology applicable to Chinese people. Methods Entrance surface doses to 1 404 examined individuals from conventional radiography, computed radiography (CR) and digital radiography (DR) were investigated by non-probability sampling and using thermoluminescence dosimetry in 14 hospitals in Zhengzhou, Kaifeng and Xinyang cities in Henan province. Results The entrance surface doses from the conventional radiography, CR and DR in Henan province were in the range of 0.20-47.71, 0.16-6.89 and 0.10-10.41 mGy, respectively. The entrance surface doses were 0.16-10.05 for abdominal anteroposterior (AP), 0.20-10.36 for pelvic AP, 0.11-2.13 for lateral skull (LAT), 0.10-2.92 for posteroanterior (PA), 0.39-5.85 for chest LAT, 0.12-1.82 for chest PA, 0.16-11.67 for thoracic AP, 0.36-29.37 for thoracic LAT, 0.25-14.49 for lumbar spine AP and 1.18-47.71 mGy for lumbar spine LAT, respectively. Entrance surface doses measured in the conventional radiography were higher than in CR and DR with significantly statistical difference (Z=-8.709, -9.570, P<0.05). Entrance surface doses measured for chest PA and lumbar LAT from conventional radiography were higher than the surveyed results in the 9th National Five-Year Plan period, with difference statistically significant (Z=3.262, 2.538, P<0.05). Conclusions Entrance surface doses to chest PA and LAT from radiography and CR were higher than the guidance levels of medical radiation exposure. Entrance surface doses from radiography to some exposed parts were higher than the levels surveyed in the 9th National Five-Year Plan period. Key words: Radiography; Examined patients; Entrance surface dose