Computed tomography pulmonary angiography with low dose contrast medium optimization research in dual-source CT / 实用放射学杂志

ABSTRACT

Objective To explore the feasibility of high-pitch CT pulmonary angiography (CTPA)with low dose contrast medium optimization in dual-source CT.Methods Eighty patients with high risk of pulmonary embolism who underwent CTPA on a dual-source CT were divided into two groups randomlyGroup A,40 patients,50 mL contrast medium per patient,with conventional bolus tracing scanning;Group B,40 patients,contrast medium=body weight×0.3 mL/kg,with test bolus of small dose contrast agent. Pulmonary artery CT value,the differences of CT values in the paired PA and PV,SNR,CNR,radiation dose of two Groups were compared by two sample t-test.The positive rate of pulmonary embolism and the subjective indexes for assessing CT image quality were compared byχ2 test.Results There were no difference of the positive rate of PE between two Groups (P =0.655),and no sta-tistical difference for image quality scores between two Groups(P =0.1 74).The MPA CT value and the differences of CT values in the paired PA and PV in L-SⅢ of Group B were higher than those in Group A (P =0.001).However,no significant differences in CNR and SNR in MPA were observed between the two Groups(P =0.250,0.203,respectively).The ED of Group B was lower than that of Group A (P =0.001).Conclusion High-pitch CTPA in dual-source CT with lower dose contrast medium optimization can minimize the amount of contrast agent while meeting the clinical requirements.