Investigation of low-dose radiography for the lumbar spine using digital radiography system

Objective To evaluate the low dose performance of digital radiography(DR)system for radiography of the lumbar spine.Methods In the experiment CDRAD2.0 contrast-detail phantom was used for the evaluating the relation between the image qualities of both the computed radiography(CR)and digital radiography(DR)and the entrance surface dose(ESD).Thirty images of adult lumbar spine were radiographed by CR and DR separately,with ESD of DR being set at 1/3 of that of CR.Six radiologists reviewed the images obtained with both CR and DR,focusing on the details of bone trabecula of the first and second lumbar spine.Results In separate reading of either CR or DR images by the two groups,the results showed no statistically significant difference between CR and DR(t=0.369,P0.05).In cross- comparison reading,the results also showed no statically significant difference in the image details of bony trabecula between CR and DR(t=0.471,P0.05).Conclusion The superior resolution,low noise and high detective quantum efficiency(DQE)characteristics of DR can be utilized to decrease the radiation dosage,while not compromising the imaging quality.