The influence of different CT scanning protocols on AI detection efficiency and radiation dose of solid nodules in chest phantom / 中华放射医学与防护杂志

ABSTRACT

Objective:To investigate the radiation dose and detection efficiency of artificial intelligence (AI) system for solid nodules in chest phantom with different scanning protocols.Methods:A total of 60 simulated nodules with different CT values and diameters were uniformly placed in each lung lobe and lung segment of the anthropomorphic chest phantom. GE Revolution evo CT was used to scan the chest phantom. 64 groups of images with different scanning parameters were collected at the tube voltage of 80, 100, 120, 140 kV, different noise indexes (NI 10-40 with interval 2), and other fixed parameters. The detection result of simulated nodules were recorded on AI software, and the detection rate and false detection rate were calculated, respectively, for different shapes of nodules. The mean volume CT dose index (CTDI vol) and dose length product (DLP) of each scan were recorded. Results:There were no statistically significant differences in the detection rate and false detection rate of spherical nodules and irregular nodules at different tube voltages( P > 0.05), but there were and statistically significant with different noise indices ( F=10.57, 17.77, 9.33, P < 0.001). Different tube voltages had no statistical significance for CTDI vol and DLP ( P > 0.05), while different noise indices had statistical significance for CTDI vol and DLP ( F=59.87, 60.92, P < 0.001). The detection rates of nodules were moderately or weakly correlated with noise indices, CTDI vol and DLP ( r=0.43, 0.56, -0.58, -0.78, P<0.05), but no correlation with tube voltage ( P>0.05). Conclusions:Scanning protocol has an impact on AI detection efficiency of pulmonary nodules. Reasonable scanning parameters should be selected according to different image quality requirements in clinical practice.