Study of the Effects of MSCT Pitch on Radiation Dose and Image Quality in Lower Limb Angiography

Purpose To discuss the effects of MSCT pitch on radiation dose and image quality in lower extremity angiography.Materials and Methods 60 cases with lower extremity arterial disease were included and randomly divided into three groups by MSCT pitch(group A:1.375 group B:0.984,group C:0.516) CT dose index(CTDIvol),DLP,the efficiency of X-ray were evaluated as parameters of radiation dose.The quality of the images were assessed and scored 1 to 4 points by two experienced radiologists.F-test was performed to analyze the image quality,acquisitiontime and radiation dose.Results The radiation dose level of group A [CTDIvol:14.94m Gy,DLP:1698.75±74.78 mGy/cm] was 28.4%lower than that of group B [CTDIvol:20.87mGy,DLP:2331.87±62.62mGy/cm](P0.05),and 62.5% lower than group C [CTDIvol:39.83mG,DLP:4485.69±205.00mGy/cm] by(P0.05),There was no significant difference in noise levels among the groups(P0.05).The acquisition time of Group A was significantly shorter than those of group B or C(12.34±0.54 vs.17.04±0.44 and 32.78±1.49,respectively,P0.05).Conclusion The scanning pitch 1.375 resulted in lower radiation dose and higher image quality in clinical imaging of lower extremity angiography.