Objective To investigate the value of low tube voltage and low dose contrast agents combined with artificial intelligence iterative reconstruction(AIIR)in upper limb CT angiography(CTA)for displaying arteriovenous fistula(AVF).Methods Totally 65 patients with chronic renal failure and suspected AVF stenosis who underwent upper limb CTA were prospectively enrolled and randomly divided into conventional-dose group(CD group,n=30)and low-dose group(LD group,n=35).In CD group,CTA was acquired using conventional tube voltage(100 kVp)and contrast agents dosage(1.0 ml/kg body mass),and conventional hybrid iterative reconstruction(HIR)was used to reconstruct images(group A),while in LD group,CTA was collected using 80 kVp and contrast agent dosage of 0.6 ml/kg body mass,and images were reconstructed with HIR(group B)and AIIR(group C),respectively.Then subjective and objective assessment of imaging quality were performed,respectively,the results were compared among groups,while the radiation dose and dosage of contrast agents were compared between CD and LD groups.Results No significant difference of subjective score of imaging quality nor confidence for diagnosing AVF stenosis was found between group A and group C(both P＞0.017),and all the above scores were higher than those in group B(all P＜0.017).Signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)of subclavian artery,brachial artery and radial artery in group C were all higher than those in groups A and B(all P＜0.017),while no significant difference of SNR nor CNR was found between group A and B(all P＞0.017).The volume CT dose index,dose length product and dosage of contrast agent in LD group were all lower than those in CD group(all P＜0.001).Conclusion Low tube voltage and low dose contrast agents combined with AIIR in upper limb CTA for displaying AVF could reduce radiation dose and contrast agents dosage under the condition of ensuring imaging quality.

Objective To investigate the value of low tube voltage and low dose contrast agents combined with artificial intelligence iterative reconstruction(AIIR)in upper limb CT angiography(CTA)for displaying arteriovenous fistula(AVF).Methods Totally 65 patients with chronic renal failure and suspected AVF stenosis who underwent upper limb CTA were prospectively enrolled and randomly divided into conventional-dose group(CD group,n=30)and low-dose group(LD group,n=35).In CD group,CTA was acquired using conventional tube voltage(100 kVp)and contrast agents dosage(1.0 ml/kg body mass),and conventional hybrid iterative reconstruction(HIR)was used to reconstruct images(group A),while in LD group,CTA was collected using 80 kVp and contrast agent dosage of 0.6 ml/kg body mass,and images were reconstructed with HIR(group B)and AIIR(group C),respectively.Then subjective and objective assessment of imaging quality were performed,respectively,the results were compared among groups,while the radiation dose and dosage of contrast agents were compared between CD and LD groups.Results No significant difference of subjective score of imaging quality nor confidence for diagnosing AVF stenosis was found between group A and group C(both P＞0.017),and all the above scores were higher than those in group B(all P＜0.017).Signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)of subclavian artery,brachial artery and radial artery in group C were all higher than those in groups A and B(all P＜0.017),while no significant difference of SNR nor CNR was found between group A and B(all P＞0.017).The volume CT dose index,dose length product and dosage of contrast agent in LD group were all lower than those in CD group(all P＜0.001).Conclusion Low tube voltage and low dose contrast agents combined with AIIR in upper limb CTA for displaying AVF could reduce radiation dose and contrast agents dosage under the condition of ensuring imaging quality.

Objective:To establish autoverification rules for coagulation tests in multicenter cooperative units, in order to reduce workload for manual review of suspected results and shorten turnaround time (TAT) of test reports, while ensure the accuracy of results.Methods:A total of 14 394 blood samples were collected from fourteen hospitals during December 2019 to March 2020. These samples included: Rules Establishment Group 11 230 cases, including 1 182 cases for Delta check rules; Rules Validation Group 3 164 cases, including 487cases for Delta check; Clinical Application Trial Group 77 269 cases. Samples were analyzed for coagulation tests using Sysmex CS series automatic coagulation analyzers, and the clinical information, instrument parameters, test results, clinical diagnosis, medication history of anticoagulant and other relative results such as HCT, TG, TBIL, DBIL were summarized; on the basis of historical data, the 2.5 and 97.5 percentile of all data arranged from low to high were initially accumulated; on the basis of clinical suggestions, critical values and specific drug use as well as relative guidelines, autoverification rules and limits were established.The rules were then input into middleware, in which Stage I/Stage II validation was done. Positive coincidence, negative coincidence, false negative, false positive, autoverification pass rate, passing accuracy (coincidence of autoverification and manual verification) were calculated. Autoverification rules underwent trial application in coagulation results reports.Results:(1) The autoverification algorisms involve 33 rules regarding PT/INR, APTT, FBG, D-dimer, FDP,Delta check, reaction curve and sample abnormalities; (2)Autoverification Establishment Group showed autoverification pass rate was 68.42% (7 684/11 230), the false negative rate was 0%(0/11230), coincidence of autoverification and manual verification was 98.51%(11 063/11 230), in which positive coincidence and negative coincidence were respectively 30.09% (3 379/11 230) and 68.42%(7 684/11 230); Autoverification Validation Group showed autoverification pass rate was 60.37%(1 910/3 164), the false negative rate was 0%(0/11 230), coincidence of autoverification and manual verification was 97.79%(3 094/3 164), in which positive coincidence and negative coincidence were respectively 37.42%(1 184/3 164) and 60.37%(1 910/3 164); (3) Trialed implementation of these autoverification rules on 77 269 coagulation samples showed that the average TAT shortened by 8.5 min-83.1 min.Conclusions:This study established 33 autoverification rules in coagulation tests. Validation showedthese rules could ensure test quality while shortening TAT and lighten manual workload.