3.0T MR扩散加权成像鉴别良恶性咽后淋巴结的临床价值

目的 探讨3.0T MR扩散加权成像(diffusion weighted imaging,DWI)在鉴别良恶性咽后淋巴结中的临床价值.方法 收集44例伴咽后淋巴结肿大的鼻咽病变患者的临床及影像资料,所有患者均行MRI检查,根据病理活检及临床随访分为良性组13例和恶性组31例.比较DWI信号及测量表观弥散系数(appa...

The clinical value of 3.0T MR DWI in differentiating benign and malignant retropharyngeal lymph nodes

Objective To investigate the clinical value of 3.0 T MR diffusion weighted imaging(DWI)in differentiating benign and malignant retropharyngeal lymph nodes.Methods The clinical and imaging data of 44 patients with retropharyngeal lymph nodes RLNs were collected.All of the patients underwent MRI examination,and were divided into benign group(13 cases)and malignant group(31 cases)according to pathological biopsy.The DWI signal and apparent dispersion coefficient(ADC)value were compared,and the receiver operating characteristic(ROC)curve was used to calculate the optimal critical value of ADC and area under the curve(AUC),to evaluate the diagnostic efficacy and to analyze the difference of signal and ADC value of different malignant lymph nodes.Results A total of 65 lymph nodes in the posterior lateral pharyngeal group of 44 patients were included in the analysis,the ADC values of benign group(23 nodes)and malignant group(42 nodes)were(0.833±0.095)×10^-3 mm²/s and(0.737±0.136)×10^-3 mm²/s,respectively,and the difference was statistically significant(P=0.004).The ADC value of 65 lymph nodes(both benign and malignant)were used to determine benign and malignant lymph nodes and draw ROC curve,and AUC was 0.756.With 0.769×10^-3 mm²/s as the best diagnostic cut-off value,the sensitivity for the diagnosis of benign and malignant was 78.3%,and the specificity was 64.3%.The ADC values of the malignant lymph nodes in the signal uniform group and the inhomogeneous group were(0.688±0.092)×10^-3 mm²/s and(0.787±0.156)×10^-3 mm²/s,respectively,and the difference was statistically significant(P=0.016).The ADC values of the maximum short diameter of malignant lymph nodes≤10 mm goup and>10 mm group were(0.745±0.146)×10^-3 mm²/s and(0.731±0.131)×10^-3 mm²/s,respectively,and the difference was not statistically significant(P=0.748).Conclusion The ADC value of 3.0 T MR DWI is an important reference for the differential diagnosis of benign and malignant postpharyngeal lymph nodes.Moreover,DWI can further improve the detection rate of small metastatic retropharyngeal lymph nodes with the maximum short diameter<5 mm.