Effect of tube voltage on digital chest radiograph for phantom and occupational exposed workers

Objective To explore the image quality of different tube voltage on digital chest radiograph for contrast detail phantom (CDRAD2.0) and occupational exposed workers.Methods The CDRAD2.0 phantom DR images of high KV and different tube voltages were analyzed by 3 readers,image quality figure (IQF) were calculated and compared ;at the same time 136 exposed workers were examined with high-kV and DR chest radiograph of different tube voltages.Contrast to high-KV images,10 anatomic sites were scored.The image differences were compared between DR and high-kV.Results On CDRAD2.0 phantom,the IQF value of DR images in 3 readers were minimum in the condition of 120 kV,average value was 22.25.The analysis of variance in model with random effects,the mean IQF value of different tube voltage DR image had a significant difference (F=13.775,P＜0.01) ;By Dunnett t-tests analysis,the mean IQF value of DR image in 120 kV and high kilovoltage had no difference (t=-0.58,P=0.979); On clinical cases,the DR image of 120 kV showed the closest anatomy to the high KV,the mean had no significant difference with 0 (P＞0.05) with single sample t test.Conclusion On the CDRAD2.0 phantom or clinical exposed workers,the DR image quality of 120 kV tube voltage equals to high-KV basically. Key words: Tube voltage; Phantoms, imaging; Radiolography, digital