The application of low-dose test method combined with variable helical pitch technology in CT angiography of lower extremity arteries / 实用放射学杂志

ABSTRACT

Objective To evaluate the application efficacy of low-dose test method combined with variable helical pitch(VHP)technology in computed tomography angiography(CTA)of lower extremity arteries.Methods Eighty patients with CTA imaging of bilateral lower extremity arteries were selected and divided into group A and group B on average.VHP technology was used in group A,and conventional fixed pitch scanning was used in group B.The objective and subjective image quality of the two groups were compared,and the radiation dose and contrast agent dosage of the two groups were recorded and compared.Results The subjective image quality evaluation of group A was significantly better than that of group B,and the difference was statistically significant(Kappa test,P<0.05).In the objective image quality evaluation,the CT value and signal-to-noise ratio(SNR)value of the common iliac artery,popliteal artery and anterior tibial artery in group A were higher than those in group B at the same level,and the differences were statistically significant(P<0.05);The effective dose(ED)value in group A was(6.74±1.20)mSv,and that in group B was(7.93±1.78)mSv(P<0.05).The dosage of contrast agent in group A was significantly lower than that in group B[(73.97±12.15)mL in group A,(82.50±2.61)mL in group B](P<0.05).Conclusion Low-dose test method combined with VHP technology not only can reduce the radiation dose and contrast agent dosage,but also can effectively improve the success rate and image quality of lower extremity arteries examination,which is worthy of clinical application.