[Values of Longitudinal and Transverse Plane Ratios in Predicting the Risk of Malignant Thyroid Nodules]

Objective To compare the predictive value of different ratio measurement in predicting the risk of malignant thyroid nodules and to determine the best value of ratio in diagnosing thyroid nodules.Methods The clinical data of 342 thyroid nodules diagnosed by ultrasonography and confirmed by histology in our hospital from January 2018 to August 2018 were analyzed.The ratio of nodules in different sections,including longitudinal plane ratio(A/T_L)and transverse plane ratio(A/T_C),was obtained through the maximum head-foot diameter(T_L),the maximum left-right diameter(T_C),and the anterior-posterior diameter(A)of transverse section measured by ultrasonography.The correlation of histological diagnosis of benign or malignant nodule with longitudinal ratio and transverse ratio were analyzed.Results The A/T_C and A/T_L of malignant nodules were 1.00(0.83,1.17)and 0.81(0.65,1.00),respectively,which were significantly higher than those of benign nodules [0.81(0.67,0.93)(Z=-6.567,P=0.000)and 0.63(0.52,0.75)(Z=-7.239,P=0.000)].The area under the ROC curve of A/T_C and A/T_L was 0.734 and 0.712,respectively,showing no significant difference(area difference:0.0210,standard error:0.0213,95% CI:-0.0207-0.0627,Z=0.987,P=0.3235).The threshold values of A/T_C and A/T_L for predicting malignant nodules were 0.784 161 5 and 0.985 714 5,respectively.Conclusions Both A/T_L and A/T_C has similar diagnostic value in predicting the risk of malignant nodules.The best cutoff value of the above two ratios are 0.78 and 0.99 respectively.