Effect of training on resident inter-reader agreement with American College of Radiology Thyroid Imaging Reporting and Data System

BACKGROUND The American College of Radiology Thyroid Imaging Reporting and Data System(ACR TI-RADS)was introduced to standardize the ultrasound characterization of thyroid nodules.Studies have shown that ACR-TIRADS reduces unnecessary biopsies and improves consistency of imaging recommendations.Despite its widespread adoption,there are few studies to date assessing the inter-reader agreement amongst radiology trainees with limited ultrasound experience.We hypothesize that in PGY-4 radiology residents with no prior exposure to ACR TIRADS,a statistically significant improvement in inter-reader reliability can be achieved with a one hour training session.AIM To evaluate the inter-reader agreement of radiology residents in using ACR TIRADS before and after training.METHODS A single center retrospective cohort study evaluating 50 thyroid nodules in 40 patients of varying TI-RADS levels was performed.Reference standard TI-RADS scores were established through a consensus panel of three fellowship-trained staff radiologists with between 1 and 14 years of clinical experience each.Three PGY-4 radiology residents(trainees)were selected as blinded readers for this study.Each trainee had between 4 to 5 mo of designated ultrasound training.No trainee had received specialized TI-RADS training prior to this study.Each of the readers independently reviewed the 50 testing cases and assigned a TI-RADS score to each case before and after TI-RADS training performed 6 wk apart.Fleiss kappa was used to measure the pooled inter-reader agreement.The relative diagnostic performance of readers,pre-and post-training,when compared against the reference standard.RESULTS There were 33 females and 7 males with a mean age of 56.6±13.6 years.The mean nodule size was 19±14 mm(range from 5 to 63 mm).A statistically significant superior inter-reader agreement was found on the post-training assessment compared to the pre-training assessment for the following variables:1.“Shape”(k of 0.09[slight]pre-training vs 0.67[substantial]post-training,P<0.001),2.“Echogenic foci”(k of 0.28[fair]pre-training vs 0.45[moderate]post-training,P=0.004),3.‘TI-RADS level’(k of 0.14[slight]pre-training vs 0.36[fair]post-training,P<0.001)and 4.‘Recommendations’(k of 0.36[fair]pre-training vs 0.50[moderate]post-training,P=0.02).No significant differences between the preand post-training assessments were found for the variables'composition','echogenicity'and'margins'.There was a general trend towards improved pooled sensitivity with TI-RADS levels 1 to 4 for the post-training assessment while the pooled specificity was relatively high(76.6%-96.8%)for all TI-RADS level.CONCLUSION Statistically significant improvement in inter-reader agreement in the assigning TI-RADS level and recommendations after training is observed.Our study supports the use of dedicated ACR TI-RADS training in radiology residents.

Diagnostic value of ACR TI-RADS combined with three-dimensional shear wave elastography in ACR TI-RADS 4 and 5 thyroid nodules

Background:Three-dimensional shear wave elastography(3D-SWE)is a promising method in distinguishing benign and malignant thyroid nodules.By combining with conventional method,it may further improve the diagnostic value.The study aimed to assess the diagnostic value of American College of Radiology(ACR)thyroid imaging reporting and data system(TI-RADS)combined with 3D-SWE in ACR TI-RADS 4 and 5 thyroid nodules.Methods:All nodules were examined by conventional ultrasonography,ACR TI-RADS classification,and 3D-SWE examination.Conventional ultrasonography was used to observe the location,size,shape,margin,echogenicity,taller-than-wide sign,microcalcification,and blood flow of thyroid nodules,and then ACR TI-RADS classification was performed.The Young’s modulus values(3D-C-Emax,3D-C-Emean,and elastography standard deviation[3D-C-Esd])were measured on the reconstructed coronal plane images.According to the receiver operating characteristic(ROC)curve,the best diagnostic efficiency among 3D-C-Emax,3D-C-Emean,and 3D-C-Esd was selected and the cut-off threshold was calculated.According to the surgical pathology,they were divided into benign group and malignant group.And appropriate statistical methods such as t-test and Mann-Whitney U test were used to compare the difference between the two groups.On this basis,3D-SWE combined with conventional ACR TI-RADS was reclassified as combined ACR TI-RADS to determine benign or malignant thyroid nodules.Results:Of the 112 thyroid nodules,62 were malignant and 50 were benign.The optimal cut-off value of three-dimensional maximum Young’s modulus in coronal plane(3D-C-Emax)was 51.5 kPa and the area under the curve(AUC)was 0.798.The AUC,sensitivity,specificity,and accuracy of conventional ACR TI-RADS were 0.828,83.9%,66.0%,and 75.9%,respectively.The AUC,sensitivity,specificity,and accuracy of combined ACR TI-RADS were 0.845,90.3%,66.0%,and 79.5%,respectively.The difference between the two AUC values was statistically significant.Conclusions:Combined ACR TI-RADS has higher diagnostic efficiency than conventional ACR TI-RADS.The sensitivity and accuracy of combined ACR TI-RADS showed significant improvements.It can be used as an effective method in the diagnosis of thyroid nodules.