Contrast Application Of Real-time Ultrasound Elastography In The Cervical Malignant Lymph Nodes Before And After Radiotherapy

Objective: To investigate the changes of elastic parameters in cervical malignantlymph nodes before and after radiotherapy using ultrasound elasticity imagingtechnology, and to explore the value of elasticity imaging for radiotherapy.Methods: Using gray-scale ultrasound and ultrasound elastography in57patients with95pieces of cervical lymph nodes induced by malignant lymphoma and metastaticcervical lymph nodes proven by tissue pathology, all patients received regularradiotherapy plan. Before and after radiotherapy, each lymph node underwentconventional high frequency gray-scale ultrasound check and real-time elastography,and pictures of each target lymph node with high frequency gray-scale ultrasound andultrasound elastography imaging were saved including elastography score, elasticstrain ratio, ratio between elastic area and gray scale ultrasound area. Observe thedifference before and after radiotherapy about elastic imaging of three parameters,namely the elastography score, the elastic area and gray area ratio, strain ratio.Elastography score was analyzed before and after radiotherapy with rank sum test forpaired data. The rate of strain ratio, the ratio of elastic area and gray area wereanalyzed by paired t test statistics, the rate of strain ratio.Results:(1) Before radiotherapy,95lymph nodes,(metastatic lymph nodes65,malignant lymphoma30), elastic score of2points and3points of the disappearancerate of lymph nodes was74.19%,78.43%, respective, while disappearance rate of4 points was15.38%, the sample rate was compared using theχ2test, with statisticallysignificant difference.For the residual lost30lymph nodes, according to the WHO evaluation criteriaidentified as PR, elastography score compared before and after radiotherapy, usingpaired rank sum test. The difference was statistically significant (P<0.05).(2) PR in30lymph nodes, average strain ratio of cervical malignant lymph nodesbefore radiotherapy was (2.24±0.53), while strain ratio was (1.44±0.32) afterradiotherapy. The difference was statistically significant (t=8.621, P<0.00).(3) PR in30lymph nodes, the ratio between elastic area and gray area of malignantlymph nodes was (1.32±0.14) before radiotherapy, while the ratio between elasticarea and gray area was (1.10±0.07) after radiotherapy, with statistically significantdifference between them (t=8.867, P<0.00).Conclusion:(1) Disappearance of different elastography scores is different before andafter radiotherapy. The elastoraphy score may become an index to forecastradiotherapy curative effect.(2) For PR group, elastography score of lymph nodes changes before and afterradiotherapy. The changes of lymphoma are various. Metastatic cervical lymph nodesdecrease.(3) For PR group, the ratio of SR after radiotherapy for cervical malignant lymphnodes is lower than ratio of SR before radiotherapy. The change can show the effect oftreatment in a certain degree, indicating the decrease of peripheral infiltration stretch,the effectiveness of treatment. (4) For PR group, the ratio between elasticity imaging area and gray area is theeffective index. The effect of monitoring is possible.In short, real-time elastography as imaging index in monitoring the efficacy ofradiotherapy of cervical malignant lymph node becomes possible. The follow-up workto further need carry out.