Qualitative And Quantitative Analysis Of Contrast-enhanced Ultrasound In Differentiating Benign And Malignant Cervical Lymph Nodes

Objective: To explore the value of qualitative and quantitative analysis of contrast-enhanced ultrasound(CEUS)in differentiating benign and malignant cervical lymph nodes.Methods: The clinical data of 154 patients(158 lymph nodes)with abnormal cervical lymph nodes detected by conventional ultrasound in our hospital from January 2017 to November 2020 were reviewed retrospectively.Among them,44 lymph nodes of 43 patients underwent CEUS.The ultrasound and CEUS features of lymph nodes were collected.The perfusion patterns were divided into centrifugal type,centripetal type and hybrid type;perfusion types were divided into type I(uniform enhancement),type II(regular perfusion defect or ring enhancement),type III(irregular perfusion defect)and type IV(weak enhancement).The time intensity curve parameters of medullary portal area(central)and cortical area(peripheral)of lymph nodes were analyzed,including arrival time(AT),peak intensity(PI),time to peak(TTP),wash-in speed(C)and wash-out speed(k),and the differences between them △AT,△PI,△TTP,△C and △k were calculated.According to the pathological results,the differences of conventional ultrasound and CEUS features between benign and malignant lymph nodes were evaluated and the independent risk factors of malignant lymph nodes were analyzed.The diagnostic efficiency of each parameter was evaluated by ROC.Results: Most of the benign lymph nodes showed centrifugal perfusion(13/22,59.1%)and type I(17 / 22,77.3%),while malignant lymph nodes mostly showed centripetal(6/22,27.3%)or hybrid perfusion(13/22,59.1%)and type III(15/22,68.2%).△AT and △k(0.09±0.79 s and 0.04 ± 0.11 d B/s,respectively)of malignant lymph nodes were significantly higher than that of benign lymph nodes(-0.46±0.60s、-0.03± 0.11 d B/s).k in cortex area and △ PI(0.31±0.11 d B/s and 0.01±1.47 d B,respectively)were significantly lower than that of benign lymph nodes(0.46±0.23 d B/s 、1.38±2.07 d B).Perfusion type III or IV,△AT≥0s and △k≥0d B/s were independent risk factors for malignant lymph nodes(P < 0.05,OR > 1).The sensitivity of conventional ultrasound,CEUS and their combination in differentiating benign and malignant lymph nodes were 86.4%,81.8% and 90.9%,the specificity were 68.2%,81.8% and 63.6%,the accuracy were 77.3%,86.4% and 77.3%,respectively.Conclusions: CEUS qualitative and quantitative analysis can provide valuable basis for the differentiation of benign and malignant cervical lymph nodes.Combined application of CEUS with conventional ultrasound can further improve the diagnostic sensitivity.