磁共振灌注加权成像鉴别良恶性淋巴结的实验研究

Experimental study of MR perfusion-weighted imaging in differentiating the benign from metastatic lymph node in rabbits

目的探讨T2*WI灌注成像鉴别良、恶性淋巴结的价值。方法 20只健康新西兰白兔随机分为两组,分别建立淋巴结炎(良性组)和淋巴结转移(VX2组)模型。由两位放射科医师分别独立勾绘感兴趣区,获得淋巴结灌注的时间信号曲线,并计算灌注参数:达峰值时间、最大强化速率及峰值增强率。结果 VX2组淋巴结的最小径明显较良性组大(P<0.01)。VX2组9只(90%)及良性组8只(80%)的淋巴结灌注的时间信号曲线均为"速升速降"型。两位观察者所测参数可重复性较高(γ>0.800)。两组淋巴结灌注参数之间均有统计学差异(P<0.05)。结论在时间信号曲线基础上的半定量灌注参数可判断良恶性淋巴结。

Objective To explore the differences of perfusion parameters with perfusion-weighted imaging（T2＊WI） between metastatic and benign lymph nodes.Methods Twenty Newzeland rabbits were divided randomly into two groups of the benign inflammatory lymph node model（group C） and malignant lymph node metastatic model（group VX2）.Two readers drawn the interest region and make the time-intensity curve（TIC）,respectively.The time to reach the peak（TTP）,the maximal slope descending（MSD%） and the peak heighted（PH%） were calculated.Results Lymph nodes of group VX2 were bigger than those of group C （P0.01）.The same shape of TIC,including obvious steep down slope,upslope and a long plateau,was shown in 9 cases（90%） in group VX2 and in 8 cases（80%） in group C.The results from two readers were very similar（γ0.800）.The differences of TTP,MSD% and PH% were significant between two groups（P0.05）.Conclusion Based on the TIC,the semi-parameters can differentiate the benign inflammatory lymph node from malignant metastatic lymph node.