60kVp管电压联合人工智能迭代重建在上肢血管内瘘CTA中的应用OA

Objective To investigate the application and value of ultra-low tube voltage(60 kVp)combined with an artificial intelligence iterative reconstruction(AIIR,United Imaging Healthcare uExceed R001)in CT angiography(CTA)of upper limb arteriovenous fistula.Methods Ninety patients with chronic renal failure undergoing upper limb arteriovenous fistula CTA were prospectively enrolled.Using a random number table,they wer randomly assigned to a conventional dose group(100 kVp,1.0 mL/kg contrast medium,hybrid iterative reconstruction;n=45)and an ultra-low dose group(60 kVp,0.5 mL/kg contrast medium,AIIR reconstruction;n=45).Two senior radiologists independently assessed subjective image quality and diagnostic confidence for anastomotic stenosis using a 4-point scale.Cohen's Kappa was used to evaluate inter-observer agreement.The radiologists quantitatively analyzed the mean CT attenuation,signal-to-noise ratio(SNR),and contrast-to-noise ratio(CNR)at the subclavian,brachial artery,and radial artery levels.Radiation dose and contrast medium usage were compared between the two groups.Differences between the two groups were compared using the independent sample t-test,Mann-Whitney U test or chi-square test.Results There were no statistically significant differences in age,sex,body weight,and body mass index between the two groups(P>0.05).Image quality and fistula diagnostic confidence scores were≥3 points,meeting clinical diagnostic requirements,with good interobserver agreement(Kappa>0.72).Quantitative measurements showed that the ultra-low dose group had significantly higher SNR and CNR values at all measured vascular levels compared with the conventional dose group(all P<0.001),including the subclavian artery,brachial artery,and radial artery.The effective radiation dose in the ultra-low dose group was significantly lower than that in the conventional dose group(1.28 mSv vs.6.50 mSv,P<0.001),reduced by approximately 80%.Contrast medium volume decreased from 61.0 mL to 28.5 mL(53%reduction),and iodine load decreased from 21.35 g to 11.40 g(47%reduction).Conclusion Ultra-low dose combined with AIIR in upper limb arteriovenous fistula CTA can significantly reduce radiation dose and contrast medium usage while maintaining or improving image quality and diagnostic confidence.It demonstrates potential clinical value,particularly suitable for high-frequency follow-up in dialysis patients.