摘要目的 探讨淋巴结实质区和坏死区的表观扩散系数(ADC)值对颈部淋巴结病变的鉴别诊断价值.方法 对36例颈部淋巴结转移癌、19例淋巴瘤和23例淋巴结结核患者进行扩散加权成像(DWI),测量并比较不同病变巾淋巴结实质区和坏死区的ADC值,评价两者对3种淋巴结病变的鉴别诊断能力.共对病理(114枚)和临床随访(63枚)证实的177枚淋巴结进行ADC值的测量和分析,其中转移癌性淋巴结84枚,淋巴瘤性淋巴结40枚,结核性淋巴结53枚.2组均数的比较采用独立样本t检验,2组以卜均数的比较采用单向方差分析(one-way ANOVA).结果 转移癌、淋巴瘤和结核的淋巴结实质区的ADC值分别为(0.93±0.16)、(0.64±0.13)和(1.01±0.11)×10-3mm2/s(F=82.928,P<0.01),淋巴结转移癌和结核中淋巴结坏死区的ADC值分别为(2.02±0.36)、(1.25±0.15)×10-3mm2/s(t=12.045,P<0.01).当淋巴结实质区的ADC值≤0.77×10-3mm2/s时,诊断为淋巴瘤的敏感度、特异度分别为83%和89%.当淋巴结坏死区的ADC值≥1.60×10-3mm2/s时,诊断为淋巴结转移癌的敏感度、特异度分别为88%、100%.结论 测量淋巴结的ADC值,尤其是坏死区的ADC值有助于淋巴结病变的鉴别诊断.

abstractsObjective To evaluate the apparent diffusion coefficient (ADC) of parenehyma and necrosis in distinguishing among metastatic lymph nodes, lymphoma and tuberculous lymph nodes. Methods Thirty-six patients with cervical lymph nodes metastasis from the head and neck squamous cell carcinomas,19 patients with lymphoma and 23 patients with lymph nodes tuberculosis underwent diffusion-weighted imaging. The ADC values were measured and compared in parenchyma and necrosis of 177 lymph nodes confirmed by histopathology (n = 114) and clinical follow-up (n = 63). The means between two groups were compared by t-test, and one-way analysis of variance (one-way ANOVA) was used to analyze the data among three or more groups. Results The mean ADC values of parenchyma in metastatic nodes, lymphoma and tuberculous nodes were (0.93±0.16) × 10-3mm2/s, (0.64±0.13) × 10-3mm2/s and (1.01±0.11) ×10 -3 mm2/s respectively (F = 82.928, P < 0.01) ; the ADC values of necrosis in metastatic and tuberculous nodes were (2.02 ± 0. 36) × 10-3 mm2/s and (1.25 ± 0.15) × 10-3 mm2/s respectively (t = 12.045, P <0.01). An ADC value of parenchyma lower than or equal to 0.77 × 10 -3mm2/s was used as the threshold for lymphoma, with a sensitivity 83% and specificity of 89%. An ADC value of necrotic area greater than or equal to 1.60 × 103mm2/s was used as the threshold for metastatic nodes, with a sensitivity of 88% and specificity of 100%. Conclusion The ADC value of lymph nodes, especially for their internal necrotic areas, can help judge the nature of the cervical lymph nodes.