Value of peak systolic velocity and pulsatility index and resistance index in predicting lymph node metastasis of thyroid cancer

ZHAO Fengqun; YI Zhanxiong; YAN Jing

doi:10.3969/j.issn.1002-7386.2024.21.014

Abstract：Objective To analyze the value of peak systolic velocity(PSV),pulsatility index(PI)and resistance index(RI)in predicting lymph node metastasis(LNM)of thyroid cancer(TC).Methods One hundred and fourteen TC patients treated from September 2020 to September 2023 were selected as the experimental group,and 114 health examination subjects during the same period were selected as the healthy group.All of them were managed by color Doppler ultrasonography,aiming to compare PSV,PI and RI.Meanwhile,the comparisons of PSV,PI,RI,blood flow grading and ultrasound features in TC patients with LNM(LNM group)or without LNM(non-LNM group)were conducted.Receiver operating characteristic(ROC)curve was drawn to analyze the predictive efficacy of PSV,PI and RI for LNM.Results The experimental group presented significantly higher PSV,and lower PI and RI than the healthy group(all P＜0.05).LNM group had significantly higher PSV,and lower PI and RI than the non-LNM group(all P＜0.05).The blood flow grading in the LNM group was mainly grade 2 and grade 3,while that in the non-LNM group was mainly grade 0 and grade 1,and with statistically significant difference between groups(P＜0.05).The proportions of patients with chaotic blood signals(66.67％vs 40.00％),rich blood flow(83.33％vs 44.44％),micro calcification(50.00％vs 24.44％),unclear border(45.83％vs 22.22％),uneven internal echo(58.33％vs 32.22％),lymph node(LN)long-to-short diameter(L/S)ratio＜2(54.17％vs 22.22％)in the LNM group were significantly higher than those in the non-LNM group(P＜0.05).The optimal cut-off value of PSV,PI and RI was 17.82cm/s,1.31 and 1.29,respectively.The area under the curve(AUC)of combination of PSV,PI,and RI in predicting LNM was 0.855[(95％confidence interval(CI:0.814-0.957)].The sensitivity of combined detection of PSV,PI and RI was significantly higher than that of single detection(94.62％vs 78.96％,76.36％,73.82％,P＜0.05).The specificity of combined detection of PSV,PI and RI was comparable to that of single detection(84.13％vs 78.64％,80.18％,76.07％,P＞0.05).Conclusion TC patients presented relatively higher PSV,PI and RI relative to healthy groups,and the increase of PSV,PI and RI is related to LNM,to a certain some extent,the combined detection of PSV,PI and RI improve the sensitivity of predicting LNM.